Buck Jumping on Mass

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Will L
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Re: Buck Jumping on Mass

Postby Will L » Thu Jul 30, 2020 1:18 pm



Just reacting to a proliferation of red underlined words Keith. As a champion misspell-er I'm very sensitive to such things.

Edited (inevitably) for spelling
Last edited by Will L on Mon Aug 24, 2020 11:52 am, edited 1 time in total.

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Will L
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Buck Jumping on Mass - The Build Phase

Postby Will L » Sun Aug 09, 2020 1:15 pm

Part 21 – Fitting Boiler to Body

When I decided that I wanted the boilers to be removable, my going in position was to assume I would need to bolt them down in two places, From under the footplate into the smokebox/smokebox saddle, and from within the cab into firebox end of the boiler. I have successfully used this approach before in the J10 which starred in my early posting on the use of CSBs. The J10 had a white metal footplate which was pretty flexible and needed the boiler to keep the overall ensemble rigid, but, for these little brass built tank locos, the footplate and cab assembly was already pretty rigid.

As I worked on them, I discovered that the tank top plates that butt up to/overlap the boiler actually do a good job of keeping the boiler where it is meant to be. As a result I decided to omit the bolt at the firebox end and just provide a ledge on the cab spectacle plate on which the firebox end of the boiler could sit.

Both kits were designed so the smokebox was positioned by a slot in the footplate which mated with a tab at the bottom of the smokebox front plate. The rest of the saddle needs to be finished off flat and square so it sits on the footplate with no gaps. I was going to use a 12BA bolt run up from under the footplate through the saddle into the boiler. Given that the sandboxes sit on the footplate and hide the meeting with the saddle sides, the joints where I needed to be most careful about visible gaps were, between the front of the smokebox and the footplate, and between the fire box end of the boiler and the spectacle plate.

The J69

I did this one first and started by trying to sort out the smokebox saddle end of things, and as often happens the best laid plans don’t survive the first engagement with the enemy. Using the tab on the smokebox front to locate it on the footplate wasn’t going to work. The slot was obstructed, partly by the captive chassis fixing nut, and partly by the pad constructed under the front of the footplate to space it from the chassis (which we discussed in Part 9 - The body is a foot... plate). It was also true that the footplate in this area was distinctly thin and fragile. It was a single sheet of 10 thou brass half etched in this area from underneath. I was clearly going to need to reinforce it as tightening up the bolt would have distorted it out of shape.

An oblong of 20 thou scrap etch, which would fit within the underside of the saddle, was soldered to the top of the footplate where the back of the saddle would locate against it. A hole, tapping size for 12BA, was drilled centrally through this and the footplate. Having filed back the front edge of the captive nut to allow it, the slot in the footplate was filled and a thin metal strip formed into an up-stand that would fit just inside the front of the saddle. A little judicious use of a file ensured the open underside of the saddle fitted snugly around these two. The drilled hole was extended upward into the boiler tube. In the boiler it was tapped 12BA and the original hole was then opened out to 12BA clearance. The result, while not very pretty internally, did locate the smokebox saddle firmly and accurately on the foot plate.

Buck J69 boiler fix.jpg
Buck J69 boiler fix.jpg (60.59 KiB) Viewed 3553 times


When bolted down, the boiler ran back level and at the right height just under the edge of the tank top sheets, but it was between 10 and 15 thou short of the Spectacle Plate. The instructions did warn that accumulated bending and fitting errors were inclined to give this result. There was an easy fix, a piece of 15 thou scrap etch was soldered flat across the end of the remaining boiler tube at the fire box end. Once the excess metal is filed away you are left with the boiler extended by the required amount. Now when the boiler was bolted down it was a snug fit against the spectacle plate.

I provided a lip on the cab front for the boiler to sit on. This was made from more scrap etch filed to the profile of the inside of the boiler tube. With the boiler tube bolted in place, I carefully soldered the lip to the spectacle plate so it was tight against the tube while, ensuring the boiler was being held snugly against the tank top plates and hence at the right height.

I then made the interesting discovery that, when I assembled boiler to body they went together with a satisfying click. The boiler was held firmly in place even without the bolt.

The J65

On this one, the slot in the footplate was available to take the tab on the smoke box front. When this was engaged the saddle sat neatly on the footplate and didn’t need any further alignment. The reinforcement for the bolt was still required. It was attached below the footplate this time, ensuring it was clear of the frames. As before the bolt hole was drilled through the reinforcement and into the boiler tube and tapped to suit a 12BA bolt. The boiler again fitted snugly against the tank top plates and again came up about 10 thou short of the spectacle plate, so the tube was extended as before.

A pleasant surprise

By now I had begun to realise just how snugly these boilers were fitting in place, and that given the snug fit against the tank top plates that the lip on the spectacle plate may well be unnecessary. Certainly true on the J65, which without it still goes together with a satisfying click, and reliably stays assembled and handleable without the smokebox bolt. Since then I’ve completely given up bolting on the boilers while I’m still working on them. Once you have fitted the chimney (coming soon), you can happily pick up either one by it and be sure they won’t fall apart. I will put the bolt in on final assembly, for security of mind yes, but also it has developed a further use as a way of securing in place a slug of lead in the boiler/smokebox area. The pictures show my removable boilers do fit well leaving no unsightly gaps. Neither is bolted together in these pictures. On the J69 (left) you can just see how the boiler has been extended.

Buck Gaps.jpg
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RC 39281

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Will L
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Buck Jumping on Mass - The Build Phase

Postby Will L » Sun Aug 23, 2020 5:31 pm

Part 22 – Fitting Boiler Fittings, Making a Start

Now is the time to consider all the rest of the bits that need fitting too the boilers. The most obvious being the chimney, dome and safety valve but there are plenty of others.

Before we get there

On the J69, because the tank fronts have been modified from the kit design to something closer to the prototype, from the classic ¾ front view, the fact that the boiler barrel has been cut away behind the tanks becomes visible. To cure this, it was necessary to add about 3mm more metal to the boiler barrel. However, due to the way the chassis fits into the body of the J69, there was already little or no clearance for the end of the motor to pass the end of the boiler tube when putting the two together. The boiler may be removable, but it has to go on before the chassis is fitted. Therefore the metal was replaced on the sides of the boiler in the form of 3mm wide strips, but a gap was left under the barrel to allow the motor to pass. Fortunately this gap is not visible from the outside. The strips were bent to the curvature of the barrel, soldered in place and filed to the right profile. The added on bits are visible in this photo which we have seen before.

Image

Despite the tanks being significantly smaller on the J65, the difference in the way they are attached to the chassis (see in Part 9 - The body is a foot... plate, again) meant the motor slides neatly into the boiler barrel when fitting the chassis. This is even though, as this photo from earlier on shows (J65 above J69 below), there is significantly less room. In addition, for some reason the cut away in the boiler was not so obviously visible past the modified tank fronts on this loco and thus it didn’t need any extra work. N.B. the rear shafts on the motors, seen in the photo, will have to be removed, but I leave enough that I can still get hold of it and turn the motor. That way I can easily turn the wheels on the assembled chassis

Image

The hole issue

When that was sorted it was time to drill a few holes. The chimney and dome holes were already there but that left quite a few to go, in accordance with the locos chosen way back in Part 1– Let battle commence.

On the J65 (no. 7155):- the safety valve/whistle seat; three handrail knobs; two clack valves; the early Worsdall pattern blower valve controls; plus a support for its operating rod; and the Westinghouse pump exhaust. Not to mention deepening the slot the top lamp bracket goes into that we have discussed before

On the J69 (no. 7054):- two Ross pop safety valves; the whistle; two clack valves; 4 handrail knobs*; the vacuum ejector exhaust; and the Westinghouse exhaust. Plus that lamp bracket slot.
* This loco had the later “standard” pattern blower valve, operated through the handrail. This necessitates one extra handrail knob on one side of the smokebox, one either side of the blower valve operating crank, which, come to think of it, also needs a hole.

Both locos had lost the Macallan variable blast pipes that the GER favoured in its earlier days, so that did save at least one hole each.

Having marked them all out carefully, I drilled all the holes 0.5mm, which I find is the smallest size I can reliably drill by hand without routinely breaking the drill. They then get opened up to size as required.

Boiler bands next

The boiler bands don’t need holes of course and they where the first things on. The kits provided half etched strip for the 3 bands per boiler. Only the one directly behind the smoke box goes visibly all the way round. I know there is an argument for making these bands only as thick as a transfer and applying them during the painting stage. I’ve done that in the past, but I decided I preferred doing it this way. Anybody who wants a GER era loco, where the band immediately adjacent to the smoke box was polished brass, won’t have the choice. The two bands nearer the firebox go behind/underneath the tank tops. These were bent tightly round the edge of the remaining boiler tube to hold them in place while the solder was run along the band edge. The band behind the smokebox was tacked in place at the top then held firmly in place, trimmed to length and tacked again at the bottom on both sides, before running the joint in full.

At this point it became clear just how tight the fit between boiler and tank top plates was on both locos, as, with bands on, neither boiler would now clip into place. A quick trim of the tank tops to clear the boiler bands was easy enough to do and cured the problem, but it was instructive.

Next up I will start filling in those holes.

RC 39893
Edited to correct Macallan
Last edited by Will L on Sun Aug 23, 2020 10:49 pm, edited 1 time in total.

Carlos
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Re: Buck Jumping on Mass

Postby Carlos » Sun Aug 23, 2020 7:09 pm

Thanks Will for your effort documenting the building of these engines. I'm slowly building my E22 and this thread is of immense help. I also enjoyed to talk to you and see your J65 in flesh (and I wish to have brought mine...) during Scaleforum. Please keep on!

(and you probably mean Macallan blast pipe, being McLaren a dusty F1 team... There is an instructive article at the GERS Journal about Macallan and its invention).

Carlos

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Will L
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Re: Buck Jumping on Mass

Postby Will L » Sun Aug 23, 2020 10:46 pm

Carlos wrote:Thanks Will for your effort documenting the building of these engines. I'm slowly building my E22 and this thread is of immense help. I also enjoyed to talk to you and see your J65 in flesh (and I wish to have brought mine...) during Scaleforum. Please keep on!

(and you probably mean Macallan blast pipe, being McLaren a dusty F1 team... There is an instructive article at the GERS Journal about Macallan and its invention).


Thanks for your kind words and whoops yes, spelling isn't my strong point. Original post corrected.

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Buck Jumping on Mass - The Build Phase

Postby Will L » Thu Aug 27, 2020 3:22 pm

Part 23 – Fitting Boiler Fittings, The big cast brass lumps.

We will start with the most prominent, the chimney and the dome.

The Theory and my personal hang-up’s.

I have an issue with the way these often get fitted with a very prominent lip around the edge where they meet the boiler. On the real thing the dome skirts are generally flared into the boiler cladding with little or no visible lip. The chimneys sometimes do have a lip visible, not as much as on many models but still there. If your being picky there can be prominent securing bolts (?) as well. Interestingly, for the Buckjumpers an obvious lip and bolts are a feature of the later LNER standard chimney but not of the GER stovepipe. On a model you can only really achieve that lipless look if you can recess these fittings into the boiler, as is sometimes done on RTR models. For me it is a case of making the lip as small as possible. I’ve considered modelling the bolt heads too, but so far I have chickened out.

Both kits came with rather nice-looking lost wax castings of these bits. This gave lots of choices in the chimney department, you end up with useful spares, but only one dome each. The J65 needs a GER stovepipe while the J69 had the LNER standard item. Trouble is, neither chimney nor dome sat as well on the boiler/smokebox as I would want. All had relatively thick edges to the skirts and sat with noticeable gaps between them and the boiler. In fact, I was quite despondent when I first tried the fit and wondered if I could ever be satisfied with it. After all, cast brass is much harder and more difficult to modify than white metal or turned brass. I can’t be the first person who’s found this issue and I do wonder how others have tackled it. My own solution(?) follows.

The Practice and an interesting discovery

The fit can be improved to some degree with judicious filing of the underside of the skirt, but there is only so much that can be achieved this way. I decided I would bed them down on the boiler so at least the gaps underneath were filled, then file down the skirt from above. My chosen fixing medium was, as (almost) always, solder.

When it comes to soldering on big chunks of lost wax casting, I have made an interesting discovery. That is Carr’s 100° low melt solder. While intended, I presume, for white metal work, it has the advantage that you can attach white metal to brass without the need to tin the brass first. I must admit that for soldering small bits of white metal together I would be a bit wary so I still keep stocks of the 70° stuff, but there is no doubt that for fitting chunky bits of white metal to brass the 100° stuff is the bees knees.

I have found in the past that soldering large bits of lost wax cast brass is quite tricky. They soke up a lot of heat, meaning the whole job gets very hot before the solder will run properly, if you ever get there at all, and as a result making it hard to handle without oven gloves. Worse, it can cause any other solder joints to fail even when they are well away from the current action. As the 100° stuff will take to brass without tinning, I wondered if it would work to join my lost wax castings to the brass boiler without having to get everything so hot.

The answer is a resounding yes.

All in all, it made attaching chimneys and domes significantly easier. Not only are they just as firmly attached as with any other solder, it is also possible to get them hot enough to brake the joint for minor reposition adjustments. This can be really hard to do with hotter solders. It gap fills well too. I wouldn’t do it any other way now.

Once fitted and gap filled round the edges, I cleaned away any excess solder on the boiler from around the skirt and set to work with a round file, thinning down the skirt edge. This is a much easier job than trying to reduce the thickness from underneath. The rather cruel blow up which follows shows the results aren’t perfect, as I still have a lip, but a huge improvement from when I first tried them in place.

Buck chimney and domes.jpg
Buck chimney and domes.jpg (65.2 KiB) Viewed 3257 times


Having got the two major players attached to my reasonable satisfaction, I moved on to a myriad of other bits.

RC 40251

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Buck Jumping on Mass - The Build Phase

Postby Will L » Fri Sep 18, 2020 4:20 pm

Part 24 – Fitting Boiler Fittings, The minor players.

A list of things to do here, very similar for both loco’s but with differences. Just for once I’ll cover them separately, starting with the J65. And yes there are bits on the locos in the pictures I haven’t covered yet but we will get there. Eventually.

The J65

Buck plum J65.jpg
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All the items described below are visible in this picture.

Safety valves and whistles

7155 still had Ramsbottom safety valves in my period, which come as part of another lost wax metal casting. It includes a seat which sits on the boiler that was treated like the chimney and dome. The whistle was a separate turned item that was mounted in a hole in the seat beside the safety valve. The tail of the safety valve and the operating rod for the whistle both need to pass through, but are not connected to, the cab spectacle plate. This has the necessary holes drilled/filed through, the safety valve tail goes through an oblong hole. The whistle was drilled to take a wire operating rod, and the joint between the two was reinforced with a sliver of tube which also represents the union between the two.

Blower valve

She was still fitted with its original GER pattern blower valve, which was operated via a prominent fitting on the right upper side of the smokebox. Control was via a rod from the cab which passes above the boiler through a support about half way along. The valve itself was modelled by a meaty overscale handrail knob with a short length of tube inserted in it. The control rod is 0.3mm wire and the central support was as fine and long a handrail knob as I could find. There was also a requirement for a hole drilled in the spectacle plate.

The clack valves.

On both locos, these sit on the boiler sides at the mid line. On early boilers they were directly below the centre of the dome, but by my era they are about half way from there to the smokebox. Both kits came with two of the same lost wax casting which includes the valve plus the boiler feed pipe down as far as the footplate. On the prototype this pipe continues below the footplate and was visible all the way back to the injectors under the cab. As I wanted to model the visible pipework, and given the removable boiler, I decided that the joint between the pipework and the clack valve was best at the valve itself. So the cast pipework was removed and the valve drilled to accept an appropriate size wire (0.6mm) from below. In the picture the pipe from the injector has missed the hole in the clack valve and is slightly displaced, just to prove they are separate (or because you never seem to spot everything before you take the photo). We will come back to this when we get to the below the footplate plumbing.

Westinghouse pump exhaust

Both locos are Westinghouse brake fitted and GER tanks have the pump mounted on the right tank front. These too will be a removable item on the models as they are a real pain to paint round. The pump’s exhaust pipe appears from behind the pump, effectively hiding the fact that the two aren’t actually connected. The exhaust continues along the lower boiler side just under the clack valve and disappears into the smokebox through a complicated little fitting. This has a base plate, which rivets to the smokebox, and a union with what looks like an oil lubrication pipe. What an oil pipe (if that is what it is) is doing there I don’t know, but, as it instantly disappears behind the sandbox and representing the union was already complicated enough, the oil pipe itself didn’t get modelled. The fitting was made from slivers of tube. The exhaust pipe itself was made from soft copper wire, as it follows the contours of the smokebox edge.

Smoke box top lamp bracket

As you may have noted before (see Part 10 - Toward the body beautiful ) I like my lamp brackets to be proof against handling damage in a way a single thin strip of bent brass stuck to the surface of the model rarely achieves. The lamp bracket in front of the chimney may have started life as a thin strip of scrap brass from the etch, but it was immediately folded in half and bent to shape. The two halves separated part way along to form the distinctive lamp bracket “L” at the business end. It was then soldered solid with 221° solder. The folded end was inserted in that slot at the top of the smoke box I’ve muttered about before, and it was attached to the boiler with 100° solder. Getting anything else to melt that close to so much brass wasn’t ever going to happen. I think the fact that it is over thick where it emerges from the smoke box just isn’t obvious, and the result will fight back if you catch your fingers on it.

The hand rail and its knobs.

Just three knobs on the J65. The one top dead centre of the smokebox is captive on the handrail and will only be fixed into the boiler after painting, if then. The two on the smokebox are soldered on from the inside. The handrail was carefully bent to shape. I was reminded of the remark of Beau Brummell’s valet concerning the apparent perfection of his cravat tying (These, Sir, are our failures). Let’s just say I did more than one per loco. In reality the handrail terminates on the front of the tank, while mine pass through a hole. As the handrail is very short it is really quite tricky getting this hole in exactly the right place, so that the rail looks strait from all directions. Also, there was actually a small fitting on the tank front that the rail fixed into. To solve both of these problems, a significantly bigger hole was drilled in the tank front and a length of 0.5mm inside diameter brass tube was slid over the handrail and fitted loosely into this hole. Once I was sort of satisfied with how the handrail looked, the tube was soldered into the tank front and cut off just proud of the tank front. The handrail, being inside the tube, isn’t soldered to anything (if you’re lucky, once I wasn’t) and remains removable. It will stay that way until its painted.

The J69

On the J69 these things were mostly the same but there were certain differences.

Buck Plum J69.jpg
Buck Plum J69.jpg (100.45 KiB) Viewed 3039 times

Safety valves and whistles

The J69 as two turned Ross Pop valves fitted directly into holes in the boiler, either side of a boiler band. The turned whistle also goes directly on the boiler. It was drilled and fitted with an operating rod which passes through the spectacle plate as on the J65.

Blower valves

On the J69, the blower valve is still on the right side of the smokebox, but now it is worked by a rod which passes invisibly down the inside of the handrail. What is visible is the operating crank which sits between two handrail knobs close together on the smokebox side. This crank was filed up from scrap etch as fine as I could manage. It isn’t actually connected to the handrail or the invisible rod which passes above it. We’ll come back to the handrail in a minute.

The clack valves.

Just like the J65. In this case the boiler feed pipe from the injector had yet to be fitted when the photo was taken.

Westinghouse pump exhaust & Smoke box top lamp bracket

Also just like the J65

Vacuum ejector exhaust

7054 was fitted with the Vacuum brake, and with this comes a substantial pipe which runs from the cab front and disappears into the smokebox high on the right side. At the smokebox end there was a substantial fitting with a mounting plate riveted to the smokebox and a flanged joint onto the pipe There was also a square plate with rivets in the corners where this pipe passed through the spectacle plate. 0.6mm wire made the pipe with a small section of tube plus flanges filed from scrap etch to form the smokebox fitting. This wire is left loose at both ends but is a good tight fit between cab and boiler.

Buck J69 vac eject.jpg
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The handrail and its knobs.

As explained above, there are four knobs on the J69, with two being either side of the blower valve crank. It even shorter than the J65 handrail but otherwise it was fitted in the same way.

Next time we start adding details to the footplate.

RC 41280

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Will L
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Re: Buck Jumping on Mass

Postby Will L » Sat Oct 17, 2020 2:38 pm

A quick question.

I'd like to draw on the huge knowledge base the readership of this forum represents. I'm about to install the plumbing associated with the injectors. No problem on the J65 where the injectors proper are hidden behind the footplate valance/cab floor but I do have issues with the J69. This had its injectors installed in the in the open air to the rear of the cab steps and well below the valence. My problem is that the nice lost wax casting provided in the kits does not seem to to that close to what is shown in the current GER society drawing (and nothing like the installation shown in the then current GER Society drawing printed in MRJ 35 with Mr Rices generally excellent article on Buckjumpers which started in the previous issue. Sould I accept the casting or do I need to generate something of my own?

The answer would be to crawl under the preserved example at Bressimgham but I can't see that happening any time soon, so I'm wondering if anybody out there who has pictures of the relevant part of no 87s anatomy?

Thanks in advance if anybody can help.

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Paul Willis
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Re: Buck Jumping on Mass

Postby Paul Willis » Sun Oct 18, 2020 9:34 am

Will L wrote:The answer would be to crawl under the preserved example at Bressimgham but I can't see that happening any time soon, so I'm wondering if anybody out there who has pictures of the relevant part of no 87s anatomy?

Thanks in advance if anybody can help.


Morning Will,

I have a number of pictures of no.87 in preservation. These are possibly the most relevant:

7309863002_3762b1060e_o.jpg


7932589988_f84e36614c_z.jpg
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P1059123.jpg
P1059123.jpg (49.13 KiB) Viewed 2670 times


Despite the obscuring signboard on the last image, I think the overall message is the same - it's remarkably difficult to pick out anything with certainty in the gloom underneath the locomotive.

So perhaps just model what you can see here ;-)

Cheers
Paul
Beware of Trains - occasional modelling in progress!
www.5522models.co.uk

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Will L
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Re: Buck Jumping on Mass

Postby Will L » Sun Oct 18, 2020 11:49 am

Thanks for taking the time Paul

Flymo748 wrote:Despite the obscuring signboard on the last image, I think the overall message is the same - it's remarkably difficult to pick out anything with certainty in the gloom underneath the locomotive.


There is a strong element of truth in that, but you have answered one question.

It is pointless anybody crawling under no 87.

It has been restored with the injectors (if there are there at all) behind the valence under the cab font floor. Just like the J65 in fact. You can quite clearly see the feed water pipes (conveniently bright copper) turn up and disappear behind the valence just in front of the cab. Where as, if the injectors were in their later position this pipe carries on almost to the back of the loco before turning back on its self inward and then downward to the injector. Even in the gloom, this can be quite visible once your aware of it and I badly want to replicate it, Its just the form of the injectors proper that is in question but seems to me its unlikely that anybody will be able to show what ever I do is wrong!

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Re: Buck Jumping on Mass

Postby Paul Willis » Sun Oct 18, 2020 3:55 pm

Will L wrote:Thanks for taking the time Paul

Flymo748 wrote:Despite the obscuring signboard on the last image, I think the overall message is the same - it's remarkably difficult to pick out anything with certainty in the gloom underneath the locomotive.


There is a strong element of truth in that, but you have answered one question.

It is pointless anybody crawling under no 87.

It has been restored with the injectors (if there are there at all) behind the valence under the cab font floor. Just like the J65 in fact. You can quite clearly see the feed water pipes (conveniently bright copper) turn up and disappear behind the valence just in front of the cab. Where as, if the injectors were in their later position this pipe carries on almost to the back of the loco before turning back on its self inward and then downward to the injector. Even in the gloom, this can be quite visible once your aware of it and I badly want to replicate it, Its just the form of the injectors proper that is in question but seems to me its unlikely that anybody will be able to show what ever I do is wrong!


Hi Will,

Thanks for the explanation. I disn't know quite what you were looking for,

The other photos that I have of S56/R24 Buckjumpers are all in GER days. Whilst some of the photos are quite sharp, they all have the arrangement of the "plumbing" in the same way as no.87 has been restored to.

No doubt there are plenty of photos of later LNER/early BR period locomotives in the GERJ, I don't have shortcuts or copies to them easily to hand, as they are outside my normal period of reference. You could do some digging there? I expect that you have the collection of 1-180 on CD/laptop?

Cheers
Paul
Beware of Trains - occasional modelling in progress!
www.5522models.co.uk

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Will L
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Re: Buck Jumping on Mass

Postby Will L » Sun Oct 18, 2020 5:25 pm

Paul

Thanks for the help. I've looked at many a photo and the run of the feed water pipe is clear, but it will take a close up of the injector proper answer the questions in my head.

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Will L
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Buck Jumping on Mass - The Build Phase

Postby Will L » Thu Nov 19, 2020 4:01 pm

Part 25 – Plumbing, injecting some reality – the easy bit.

Having sorted the boilers, I must return to detailing the footplate/cab assembly.

The joys of plumbing

Among other things, there is a lot of plumbing to be added which I normally enjoy doing. Therefor I am going to start with the feedater pipes, which are very visible on most Buckjumpers, and the injectors that feed them, which aren’t. In preparation, as part of my removable boilers policy, we have already added the clack valve castings, where the feedwater pipes terminate on the sides of the boilers. These valves are drilled to accept the pipe ends but the pipes themselves are attached to the footplate and simply plug into the valves on assembly. This all starts very simply but somewhere down the line grew into a monster which absorbed much time and patience.

The simple stuff

The feedwater pipes come from the injectors, of which both locos have two of the live steam variety. These are installed below the cab one each side. The pipes can clearly be seen on most Buckjumpers, running forward under the footplate not far behind the valance. They are suspended from the footplate in a few places under the tanks before turning up through the footplate and running in a gentle curve vertically to the clack valves. Prototype pictures show that, below the footplate, these pipes varied between being totally invisible to dangling around in fairly untidy curves well below the valance. However, it does seem that for the majority they ran straight and parallel just below the valance and both my locos were like this. The result at the chimney end is the same on both locos as is shown in this photo of the relevant bit of the J69 with and without boiler.

Buck J69 FW2.jpg
Buck J69 FW2.jpg (81.39 KiB) Viewed 2182 times


The nature of Injectors

Once we get to the other end of the feedwater pipe, there is a significant difference between the J65 and the J69. Their injectors are located in different places. These injectors mark the junction of 4 significant bits of plumbing. That’s the steam and water pipes in, the pressurised boiler feedwater pipe out and a water overflow/drain pipe. The development of steam driven feed water injectors was a really important step in making the steam loco a practical proposition, and strangely it is the drain pipe which makes workable the whole counter intuitive idea of being able to use steam from the boiler to force cold water into the boiler faster than the engine uses it. Of course, the same science also leads to the Vacuum Ejector which made the Vacuum Brake practical. Where would be without thermodynamics..

On all the J65s and early incarnations of the other Buckjumpers the injectors are below the front of the CAB floor. In most cases, but not all, this installation is invisible. J65 no 7155 is like that, so that apart from the feedwater pipe the only other pipework that needs bother us is the drain pipe which is clipped to the back of the cab footsteps where it dribbles visibly. The net result looks like this

Buck J65 feed water run.jpg
Buck J65 feed water run.jpg (86.54 KiB) Viewed 2182 times


The J65 was all nice and simple. The Injectors on the J69 turned into a fairly long running battle which caused me considerable grief but I think I will leave that for the next post.

RC 45695

Julian Roberts
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Re: Buck Jumping on Mass

Postby Julian Roberts » Sun Nov 22, 2020 10:21 am

and strangely it is the drain pipe which makes workable the whole counter intuitive idea of being able to use steam from the boiler to force cold water into the boiler faster than the engine uses it.


Yes Will though I think what is even more counterintuitive is that the steam (that is at boiler pressure) when combined with the injecting water overcomes that same steam pressure in the boiler to get the water through the clack valve into the boiler. Venturi effect, apparently, is part of the same process you allude to.

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Will L
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Buck Jumping on Mass - The Build Phase

Postby Will L » Mon Nov 23, 2020 5:50 pm

Part 26– Plumbing, injecting some reality – into injectors

In this part I spend a whole posting on producing two small apparently identical components

Injectors, what’s required on the J69

As the J69 were developed over time, and the GER did a lot of that, the injectors were relocated in the open air below the bunker, slightly lower than the bottom edge of the buffer beam. Injectors, particularly on hard working locos, function better if you keep them cool, hence you often find them where there is a good air flow around them. This open air location is much more visible and means that modellers now have to worry about all 4 pipes, not to mention what the injector actually looked like.

The kit came with a pair of lost wax castings labelled injectors. They may give a passable representation of what you can occasionally see poking out from behind the valance on some early Buckjumpers, but it bears little resemblance to what is there for all to see on the later J69s. If you can see in the gloom under the footplate that is. I’m afraid photos don’t help much. What is really visible is the rather convoluted run of the feedwater pipe. This is very visible and draws attention to the fact that, in the right lighting, the injectors are open to inspection. There is a small drawing of the required bit of kit on the GER society J69 drawing. Lacking any further sources of information, I used this to modify the casting to something closer to what the drawing showed. Whether it might be easier to make two new ones from scratch rather than trying to modify the casting is a good question. I modified and the result can be seen here.

Buck J69 Injectors 2.jpg
Buck J69 Injectors 2.jpg (62.45 KiB) Viewed 1958 times


How it was done

My modified effort is to the left, an original casting is to the right, It is clear that the changes are significant. Despite the drain pipe being the most visibly correct part on the original, it was too short. I was never clear as to what the diddy little pipe opposite the drain was supposed to be. There was nothing like it on the drawing. Its union with the main body was I felt, more effectively modelled so the original drain pipe and union were removed and the one on the other side trimmed and redrilled for a new drain pipe made from .6mm rod which is fitted using 212° solder which will be used for all the solder joints until I say otherwise.

Somebody elsewhere recently was having difficulty getting solder to penetrate into this sort when joining rod into a hole or a bit of tube. This is quite normal, if you want to get anything more than a ring of solder round the place where the wire enters the hole you need to:-
  1. make sure the hole is clean inside,
  2. reduce the size of the wire over some of the length that will go in the hole and tin it back to full size, and
  3. get some flux down the hole.
You will then have some usable solder down a nice clean hole when the heat arrives.


The big change to the casting is adding somewhere to accept the input water pipe. The steam feed pipe arrives in line with the body of the injector which already has the necessary hole cast in. This was drilled out to accept 0.7mm rod. While I was at it I drilled out the feedwater pipe exit hole at the other end the same size. According to the drawing the water pipe was close by and parallel to the steam pipe, giving rise to the bell shaped end to the injector body. I started by soldering in a length of rod to represent the steam feed, which also gives me something to hold on to.

I then filed off the hexagonal nut detail from that end of the injector casting.

To make the union with the water feed pipe I started with a length of brass tube the same diameter as the injector body. This was overlapped with the first millimetre of the injector casting. Where that nut detail had been a 1mm wide strip of brass shim was wrapped around both the tube and casting. You have to get the tube ¼ of a turn out of alignement with the drain pipe. On the first one it doesn’t matter which way. The whole things is then soldered up solid, still with 212° solder. The rest of the pipe is sawn off and the resultant lump on the end of the casting filed so as to tidy it up and loose the overlap in the brass shim strip. If any solder has got inside the piece of tube, then it needs drilling out.

To make the flange on the end of the bell, a big enough (small) piece of brass etch scrap was drilled to one side of the middle for the steam pipe to pass through. Thread the steam pipe through this hole and use the section of tube now attached to the side of the injector to drill a second hole for the water feed. Add the rod for the water pipe, 0.7mm again, and solder together the flange, the injector body and the water pipe. Use 147° solder and you should be able to do that without everything falling apart. Finally file off the edges of the brass sheet to form the flange and the end of the wire and tube to complete the bell shape.

Then make another

That was all a might fiddly, but not too difficult once you had worked out the method. So I set about the second one. As far as I can tell the injectors were handed so the second needs to be a mirror image of the first, therefore that ¼ turn must be the other way this time. I knew that, I checked what I was doing as I went along and yet somehow, I managed to build the second one the same hand as the first one, twice. Having to diss and re assemble was an altogether fiddlier job, but I got there in the end. If only I’d realised then, what I know now.

RC 46165

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Will L
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Buck Jumping on Mass - The Build Phase

Postby Will L » Thu Dec 03, 2020 4:33 pm

Part 27– Plumbing, injecting some reality – A dilemma

Having made my Injectors, all that remains is to fit them.

All proves to be a big word.

The remarkable thing about the injectors on the J69 is the nature of the feedwater pipe. It is clearly visible following a convoluted path which takes it right back to the rear buffer beam. It was wondering what this was all about that got me in to the whole topic of the injectors, and the fact that the J69’s are mounted in a eminently visible (given the right lighting) place under the bunker. The steam feed pipe runs rearward from the control valves on the back head and is paralleled by the water feed pipe. These go straight into the injector, meaning that the feedwater pipe also starts its journey going rearward along the loco. That is in totally the wrong direction, so it must bend through 180° before heading off to the clack valves on the leading end of the boiler. Hence the convoluted path that got my attention in the first place. This is repeated on both sides of the loco.

The Injectors are mounted close to the frames under the bunker and just below the level of the rear buffer beam. The feed water pipe bends upwards so it is protected by the buffer beam before bending through 180° so ends up going in the right direction just behind the line of the valence. Still being to far below the footplate it completes it’s convoluted path by bending upwards again until it is just below valence level. It then it takes the same path as on the J56.

The first step therefore was to bend up the feedwater pipe from it junction with the clack valves, through the footplate and along below the valence just like on the J56. It continues straight on behind the cab footsteps before being carefully bend down and round through 180° and down again to meet the injector. It’s unclear if it was clipped to the back of the footstep in real life, but I chose to solder mine there so as to give it extra support. This was done in mirror image on both sides

The fabricated injectors were soldered to the end of the feedwater pipe so it is clear of the cab step. The overflow pipe is bent first outward then forward so it too passes just behind the cab steps, to which it certainly was clipped. The net result was as in this rather cruel blow up photo. The steam and water feed pipes have yet to be delt with. This also shows why the injectors would have been handed.

Buck J69 Injector fit 3.jpg
Buck J69 Injector fit 3.jpg (100.67 KiB) Viewed 1773 times


To finish the job the feed pipes for steam and water need to turn upwards and disappear through the footplate. To do this they must go between the rear driving wheels and the under cab sand boxes which are attached to the chassis.

This is when I realised there was a snag.

As explained long ago in Part 9 - The body is a foot... plate, the J69 chassis is held under the cab end of the loco by a couple of fingers on the chassis which fit into vertical slots etched into a footplate upstand under the cab floor. The picture shows the fingers, the slots are much harder to photograph.

buck j69 bweight+f.jpg
buck j69 bweight+f.jpg (335.98 KiB) Viewed 1772 times

These fingers/slots were a fundamental part of the kit design and accurately place the chassis under the cab in all three dimensions. This means that to fit the chassis, it is first placed on the footplate forward of its proper position and overlapping the front buffer beam. It is then slid backward until the two tongues engage in their slots and it is hard up against the rear buffer beam. The other end can then drop down behind the front buffer beam and the chassis ends up fitting very snugly into place. Unfortunately, as the picture shows, the sandboxes, which those water and steam, feed pipes must pass in front of on their way up under the cab, are attached to the chassis. With those pipes passing between them and the rear driver and attaching to the footplate, nothing is going to slide anywhere.

This is what you get for adding details to a kit I suppose, and I expect I ought to have seen it coming. But I didn’t. So the question was ..

What Next

  1. I could remove the sandboxes from the chassis and fit them to the footplate but that was going to be significant surgery. Also, the footplate has a hole where the sandboxes would need to be attached, and the rear sandpipe which would now be attached to the footplate would become very vulnerable when the chassis and body were separated.
  2. I could cheat with the steam and water feed pipes by just cutting them off short behind the cab footsteps or splaying them sideways outside the sandboxes and hope that nobody noticed. I didn’t fancy that mostly because I’d know and it was just about visible.
  3. I could remove the steam and water feed pipes from the injectors, attach them to the chassis and have them plug into the injector body just like those fingers on the chassis. However it would require a significant rework of the injectors which were already an assembly of several small bits of brass and two sorts of solder.
RC 46889

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Will L
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Buck Jumping on Mass - The Build Phase

Postby Will L » Fri Dec 18, 2020 12:17 am

Part 28– Plumbing, injecting some reality – A solution

So I implemented option 3. (see previous post)

Option 3, an exercise in cutting, filing and drilling in confined spaces.

This option required me to cut off the steam and water feed pipes fitted to the injectors in part 26 and drilling them out, so I ended with up two holes instead. Into these holes, pipes attached to the chassis plug in as the chassis is fitted to the body.

This was not, I admit, all that obviously an attractive option, but much thought and an abortive attempt at option 2 persuaded me this was the way to go. None the less. I started into it with considerable trepidation as to how easy it was going to be. Given de-soldering things usually means getting them significantly hotter than when soldering them on, I had doubts about letting too much heat near my injectors. They were, after all, confections of little bits of brass and two sorts of solder. Therefore, the whole job had to be achieved with the injectors still attached to the boiler feed water pipe and the cab step.

As this whole injector process had been a bit of a struggle, I was pleasantly surprised when this last job proved relatively simple to do. The existing steam and water feed pipes (actually 0.7mm rod) were cut off and filed flush with the end of the injector. It wasn’t too hard to centre a drill on the remains of the rod and drill down it. If anything, once I’d got the drill started in the right place it seemed to want to follow the rod. I wasn’t entirely surprised when the hole went into the original casting, as cast brass is quite hard, but it was a relief when the drill did the same into my extension, made of brass scrap, brass tube and solder. As pointed out on the Forum recently, its quite hard to get solder to flow very far down a hole, and this was proved to have been true, which helped. The picture shows the modified injector. The trouble with blowing up pictures this size is that it highlights any solder residue, there is an advantage to working in NS I think. It also shows faults that aren’t immediately apparent when viewed normal size, like the slight angle on the top cab step.

Buck J69 Injector fit 2a.jpg
Buck J69 Injector fit 2a.jpg (85.54 KiB) Viewed 1573 times


Piping up

Next I needed to attach the necessary pipework to the chassis. I am allergic to soldering close to wheels with steal tyres given the tendency of the liquid flux to get everywhere. So the first job was to strip down the chassis. One of the things that makes me favour CSBs is that they do allow the wheels to drop out (relatively) easily, and I now wouldn’t consider trapping wheels in a chassis. My life seems full of occasions like this when the ability to dis-assemble the chassis becomes desirable. I think I have noted a tendency for those who build locos for others to consider drop out wheels an unnecessary complexity. I suppose that all that extra experience should ensure they get everything right first time and hence never need to back track the way I do. However, I do wonder if the fact that they say an early goodbye to most of their creations also plays a part.

So off came the removable brake gear (see Part 6a - Removable Brake Gear ). Then, having first marked the circumference of the wheels on the frames so I’m sure the pipes will be clear of the wheels even when the springs are fully compressed, out came the CSB wires and out dropped the wheels gearbox and motor.

The top edge of the chassis was notched to locate the pipes which were first bent to approximately the right shape. They have to pass from the injector body, below the sand boxes, in front of the sand pipe and up to the level of the top of the frames before they get to the driving wheel. Now out of view they were bent at right angles to pass through that notch in the frames, and at right angles again and down a bit so they run on top of the nearby chassis spacer. They were soldered one at a time to the frame spacer and into the frame notch, then adjusted so they will slide into the hole in the injector. The picture shows that one didn’t quite make it into the notch, but as it is firmly attached and the error is hidden up inside the body I couldn’t be bothered to do it again, or photograph the other side which was done properly. .


Buck J69 Injector fit 2b.jpg
Buck J69 Injector fit 2b.jpg (75.97 KiB) Viewed 1573 times

What I thought would be the final question was, how easy was it going to be to get all four bits of wire to align nicely with the 4 holes in the injectors, so the chassis and the body would assemble easily. Being well supported these wires end up quite rigid, even though they became 0.6mm wire as the 0.7 stuff I used to start with just looked a bit too big. So long as each rod had a rounded end, adjusting them so that all four fitted into the injectors simultaneously proved easier than expected, and their rigidity seems to ensure they stay adjusted. If for any reason they are not mating as they should the chassis simply refuses to go back the last couple of millimetres so there is no danger of miss assembly. The next photo shows the chassis before and after fitting to the body, just to prove it really does.


Buck J69 Injector fit.jpg
Buck J69 Injector fit.jpg (95.09 KiB) Viewed 1573 times

Last steps

Having implemented my injector solution, it was just a question of reassembling the chassis and doing one more check that everything still went together as it should. Of course it didn’t. Having had the fates on my side for once, normal service was now resumed. The problem being that because the chassis has to be placed a little further forward before it could be slid in place, the clearances at the other end were reduced and I could no longer get the motor plus power leads through the boiler cut-out. Modifying these leads so they left the motor sideways rather than backward sorted the problem. Once that was done all was well. I did try and take a picture showing all the pipework in place on the fully assembled loco, but I have to admit the only people who will notice those extra pipes are going to have be looking at it from an unusual angle. Hay Ho.

Next time we’ll have a go at the Westinghouse pumps.


An aside on small drills

Most all of the holes in my models I drill by hand. Almost inevitably I start by using my favourite 0.5mm drill, as this is the smallest size drill I can reliably use in a pin chuck without breaking it too often, and if the hole proves not to be in quite the right place you can always adjust it a bit if it needs to be bigger. If I ever considered getting machine tools for my work bench I would start with a drill press, but I continue to manage without one, and it wouldn’t have helped drilling those injectors anyway. The 0.5mm drills do break occasionally but that just means the one I’m using will be relatively new and sharp. I buy them in lots of 10.

Once I have a .5mm hole, if it needs to be bigger I normally open it out with a a five sided taper broach. A set of six of these in gradually increasing sizes, was one of my best ever tool purchase. They used to be unusual tools available in one set of sizes only, but the word seems to have spread as Eileen carries quite a range of these now. My original set had metal handles and all but the finest have lasted well. My current crop, brought to replace the broken small one, have plastic handles which tend to brake off. Milleput makes a workable replacement, and they still do the job. The finest available set goes down to 0.4mm which is the one that will break if you try to hard, and the one you need if you always start with a 0.5mm hole.

Broaches don’t help with blind holes of course, as those in the injectors were. For these I keep a set of drills in 0.05 /0.1mm increasing sizes. I don’t often use these and haven’t broken them but over time they have been getting blunt and are hard work to start a new hole with. They are fine for opening up existing holes a step at a time just so long as you don’t try and step the size up too much.

RC 47725

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PeteT
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Re: Buck Jumping on Mass

Postby PeteT » Sat Dec 19, 2020 10:14 am

Hi Will, I'm slowly catching up with the forum after a busy autumn - thanks for sharing your issues and solution with the Exactoscale axle end caps, I presume I will come across the same with those on my J39. I would have probably resorted to a blob of paint which has worked fine in the past, but like the idea of something a bit more robust yet can be made to release if required.

Thanks also for the thoughts re cutting broach handles. I too wouldn't be without mine. I have had a set for ages with plastic handles, which as you say have slowly disintegrated - and earlier this year bought a proops set to get the largest one slightly larger than the set I had - however these arrived without handles. I have made to so far using an offcut of rubber sheet to hold/grip them with, but setting them some milliput handles sounds like a very good idea.

Nice work with the plumbing, and thanks for sharing the issues with the body/chassis interface - these arent prototypes I'm ever likely to build, but these are the same issues we all have to deal with!

Terry Bendall
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Re: Buck Jumping on Mass

Postby Terry Bendall » Sat Dec 19, 2020 8:38 pm

"Will L"]Almost inevitably I start by using my favourite 0.5mm drill, as this is the smallest size drill I can reliably use in a pin chuck without breaking[/quote]

I have not had to do the sort of plumbing that Will has done but I often have a need to use small drills including down to 0.3mm. I use a small Archimedian pin chuck/drill from Eileens Emporium for the small drills and keep it just for the smaller sizes. Generally this is successful but there are the inevitable breakages. I think I have managed about 23 0.3 holes in succession in brass sheet without a breakage.

Will L wrote: If I ever considered getting machine tools for my work bench I would start with a drill press, but I continue to manage without one,


Which just shows that machine tools and elaborate workshops are not necessary for fine modelling. :)

Terry Bendall

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Will L
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Re: Buck Jumping on Mass

Postby Will L » Thu Dec 31, 2020 4:33 pm

Terry Bendall wrote:
Will L wrote:Almost inevitably I start by using my favourite 0.5mm drill, as this is the smallest size drill I can reliably use in a pin chuck without breaking


I have not had to do the sort of plumbing that Will has done but I often have a need to use small drills including down to 0.3mm. I use a small Archimedean pin chuck/drill from Eileens Emporium for the small drills and keep it just for the smaller sizes. Generally this is successful but there are the inevitable breakages. I think I have managed about 23 0.3 holes in succession in brass sheet without a breakage.
I have an Archimedean drill but I've never got on with it.
Drill.jpg

Partly this is because using it is a two handed operation which leaves nothing left for holding the object to be drilled, and partly that the stupid thing wont grip a drill smaller than 1mm which is a big drill on my workbench. So not one of my better tool purchases. Perhaps I should lash out for the Eileen spring loaded version which might overcome both objection. I may also add their pin chick with a swivel head to my armoury, as drilling with a pin chick can be very hard on your palm.

Will L wrote: If I ever considered getting machine tools for my work bench I would start with a drill press, but I continue to manage without one,


Which just shows that machine tools and elaborate workshops are not necessary for fine modelling. :)

Hum. I might just have to take that as a compliment.

Jeremy Suter
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Re: Buck Jumping on Mass

Postby Jeremy Suter » Thu Dec 31, 2020 6:39 pm

Hi will
I would not bother with the sprung loaded ones, I've had them and find the spring a waste of time especially with the smaller drills. Like you, mine are not holding what they used to. I found the answer really is not to change the drill bit very often, I change the drill instead. When it won't hold that drill size any longer I put a larger one in and buy a new one.
As for holding the drill when using small drills .3mm and .4mm I use the long one with it under my arm or into my shoulder to reduce the amount of wobble which snaps the drill a bit of spit helps as well . When they snap I sharpen them up again on a Carborundum.

IMG_5943[1].JPG

Philip Hall
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Re: Buck Jumping on Mass

Postby Philip Hall » Thu Dec 31, 2020 8:00 pm

For donkeys’ years I have done what Jeremy does. I have built up a collection of pin vices and Archimedean drills (I take the spring out of those) which have the various drill sizes in them. I have marked them so as to easily distinguish the drill sizes. In my case this is doubled up as I have the drills duplicated on two different workbenches; it’s all so much easier. It is also true that it saves a lot of time which to me is often my money and my customers’!

Philip

Terry Bendall
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Re: Buck Jumping on Mass

Postby Terry Bendall » Fri Jan 01, 2021 9:33 am

"Learn something new everyday" is an expression I have used several time on here and I find it often happens. From Jeremy I have just found out about the very long pin chucks which look interesting but, I would have to see how they are used.

Will L wrote:I have an Archimedean drill but I've never got on with it.


Interesting. I guess that it is each to his own methods which happen frequently in practical matters. The one I have fits in the palm of the palm of my hand and I then rotate it with thumb and forefinger. I don't use the activating "nut" at all. That I find works well for me.

Will L wrote:Hum. I might just have to take that as a compliment.


Credit where it is due Will. :D

Terry Bendall

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Will L
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Buck Jumping on Mass - The Build Phase

Postby Will L » Mon Jan 04, 2021 6:53 pm

Part 29 – More Plumbing – The Westinghouse Pumps

About the Westinghouse brake

When the GER finally got round to fitting its passenger stock with an automatic brake, they chose a system which was driven by compressed air, using equipment produced by Westinghouse, an American company. The GER may have recognised this was the best system for it intensively worked services, but most other UK companies opted for the vacuum brake. Perhaps because Westinghouse was an American company and “not invented here” applied, or possibly because the Westinghouse pump was mechanically more complex than the vacuum system. A vacuum ejector works on much the same principle as the steam injectors that push water into the boiler and with which the railways workshops would already be familiar. UK main line railways all eventually standardised on the vacuum brake, around the time of the grouping. In principle there isn’t a vast amount of difference between a vacuum or an air brake system, in as far as both work on the basis of a significant difference in pressure between the air in the brake pipe and atmospheric pressure. Of course, history has shown that, in practice, the air brake is the better system, but that, as they say, is life.

The most distinctive thing about Westinghouse braked railways was the presence of a pump on the side of the locos which made itself know by “panting”. A thing which was most commonly observed while locos sat at the platform having just stopped their train. You can still experience this at Porthmadog. The Ffestiniog was and remains a vacuum brake railway. The Welsh Highland was a Westinghouse railway, but was converted the first time the Ffestiniog took it over, and so it remains today. However, take a trip to the other end of town to the Welsh Highland Heritage Railway and you will find that, as befits its heritage status, it is still a Westinghouse railway, and features panting pumps. These two railways are physically connected but there is little traffic between the two. These day it seem it is this difference that is the primary reason why this remains so.

Back to the models

Both J65 and J69 are fitted for passenger work and so are fitted with Westinghouse pumps. The GER favoured mounting the pump on the front of the left hand (facing forward) tank. In the kits, the pumps come as lost wax castings. These have two pins moulded into the back which fit into corresponding holes etched into the tank fronts. What they don’t come with is any suggestion of the mass of pipework which some images show connecting to the pumps. Some of this mass is very fine bore pipes and is, I think, associated with lubrication. Fortunately this seems absent, or hidden, on some locos, so I ignored it. The pipes that must be provided are for steam in to drive the pump, compressed air out and the steam exhaust.

Buck WH pumps 1.jpg
Buck WH pumps 1.jpg (63.72 KiB) Viewed 789 times


My first picture shows one of the pumps as it came. A Westinghouse pump has two cylinders mounted one above the other with their pistons connected rigidly together. Push the top one up and down with steam and compressed air comes out of the bottom one, assuming you’ve got your valve events right. The steam enters via a valve assembly on the top cylinder which is round the back and hard to see in this picture. The exhaust and the air out are the union points on the side of each cylinder. Also visible are the two pins which will attach it to the tank front. In line with my removable boiler policy, I didn’t want to attach the pumps permanently to the locos either. Mostly because painting them and the area around them would be an absolute b…. when firmly attached to the loco. It turns out that the attachment pins were a good tight fit into the hole etched into the left tank front. Most of the pipework which I was going to fit obligingly disappears into the bodywork in quite short order too. I decided to see if I could solder those pipes to the pump, and thread the other ends through holes in the bodywork and see if they would stay put without further assistance. If necessary, I could use PVA or similar to ensure they stay put on the loco in service.

Buck WH pumps 2.jpg
Buck WH pumps 2.jpg (68.4 KiB) Viewed 789 times


The second picture shows them suitably embellished with pipework. J69 to the left anf J65 to the right. Basically the same but you may notice a subtle difference. I used some soft copper wire of approximately the right dimensions because they need to be fairly flexible. The steam feed pipe is very prominent and winds it way round the top of the pump and disappears through the part of the tank front plate which covers up the gap between tank and boiler. The air out pipe turns down and disappears through the footplate. These two fit in well with my plans and the necessary holes were drilled into the tank front and the footplate.

Exhausting progress

The exhaust pipe, however, is not so obliging, as it turns forward and runs along outside the boiler cladding to disappear into a union on the lower side of the smoke box. I decided that this one had to be attached to the union on the smokebox and to the boiler cladding below the clack valve. Those with good memories may also remember that I’ve already described doing that as part of applying detail to the boiler, which proves that I didn’t necessarily build the things in quite the order I am now describing them.

I did consider having the exhaust pipe plug into the pump. However, this is beginning to ask rather a lot of the idea that I could get a number of things pointing in different directions all pluged into their respective holes at the same time. Fortunately, the union point for the exhaust pipe is on the side of the top cylinder. On these locos this a is difficult area to see being sandwiched between the pump and the boiler side. On the J56 there is very little space and the fact that the exhaust pipe goes past the union rather than into it is not apparent. On the J69 the bigger wider tanks mean the pump is mounted further away from the boiler, but rather closer to the clack valve. The absence of any pipe entering the union on the pump would be visible, but the fact that this pipe was not continuous with the rest of the exhaust pipe wasn’t. This explains the addition little bit of extra wire visible in the J69 pump.

Result

Buck WH J69.jpg
Buck WH J69.jpg (136.76 KiB) Viewed 790 times

As it turns out the theory worked and the pins and pipes hold the pump firmly in place and I doubt that they will need further assistance to stay attached. The last photo, another cruel blow up, shows the J69 pump in place. The solder joints will (hopefully) look a lot less prominent when painted over. The gap between the smokebox and the footplate will disappear behind the sandboxes which are the next job. The handrail and one of the handrail knobs are currently adrift.

Edited to correct "The gap between the firebox and the footplate" to "The gap between the smokebox and the footplate". Ops

RC49836
Last edited by Will L on Mon Jan 04, 2021 10:32 pm, edited 1 time in total.

Daddyman
Posts: 198
Joined: Sat Jun 03, 2017 1:09 pm

Re: Buck Jumping on Mass

Postby Daddyman » Mon Jan 04, 2021 8:49 pm

Nice work, Will. None of the castings quite seem to get the top of a Westinghouse right:

20160902_105508 (1).jpg


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