Here We Go... Judith Edge Ruston 48DS Kit

nigelcliffe
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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby nigelcliffe » Sun Oct 13, 2013 9:38 pm

Preview of a tiny bit of the article's content, though on a 2mm scale loco rather than the 4mm ones in the Scalefour News articles at:
http://nigelcliffe.blogspot.co.uk/2013/07/stay-alive-capacitors-in-2mm-scale.html

Yes, I agree with Russ' comment about gearing trade-off. Selecting a motor with a relatively low speed helps no end with the gearing. The availability of decent (if sometimes expensive) small coreless motors with a lower running speed than the Sagami of this thread has made 2mm a lot easier; 30:1 or 50:1 works nicely, whereas a Sagami in 2mm scale needed well above 60:1, and often 100:1.

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Sun Oct 13, 2013 9:57 pm

The idea of using one of the newer 2mm scale motors is an interesting point. I hadn't really thought of doing that. One benefit of the Sagami is that it was also lying unused in my gloat box.The other reason is that the screw holes directly match the gearbox etch, so it is directly interchangeable with the Mashima 1020 motor that comes with the 48DS kit.

Do the new 2mm 12v can motor or the Maxon RE10 sold by the 2mm shop have the same fixings, do you know?

nigelcliffe
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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby nigelcliffe » Mon Oct 14, 2013 7:42 am

Armchair Modeller wrote:The idea of using one of the newer 2mm scale motors is an interesting point. I hadn't really thought of doing that. One benefit of the Sagami is that it was also lying unused in my gloat box.The other reason is that the screw holes directly match the gearbox etch, so it is directly interchangeable with the Mashima 1020 motor that comes with the 48DS kit.

Do the new 2mm 12v can motor or the Maxon RE10 sold by the 2mm shop have the same fixings, do you know?


I hadn't suggested using "2mm motors", just made a comment on the change in motor performance over the years altering the gearbox ratios required in models.

I doubt the 2mm SA "flat can" motor has enough power for use in 4mm scale, except perhaps an open Wickham trolley. It's broadly similar to the flat-can used by Farish in their N gauge 03/04/14 diesel shunters, though the detailed motor internals appears different, and the power/torque seems different. Its a cheap Chinese motor, sold at a "cheap motor price". I doubt the fixing centres will max the High Level gearbox holes.

The Maxon comes in many voltage ratings. Its a high precision motor from a specialist maker. Similar sized motors are also made by Faulhaber, though the peak power/RPM figure varies between each maker, and reading of specification sheets can yield useful information.
The 10mm dia x 16mm long will be marginal in 4mm scale, even in small prototypes. If you go up in size to a 12mm or 13mm dia, that will increase the torque available substantially. I think the 12mm dia version from Faulhaber is pretty much the same specification as that used in Portescap gearboxes. For one-off's of these motors, the industrial importers are sometimes either very expensive, or difficult to deal with; SB Modellbau provides one retailer who carries some of them.
The fitting on small cylindrical precision coreless from Maxon and Faulhaber are the same, a screw thread on the motor nose, concentric with the output shaft; the photo on the 2mm site shows this clearly on the left of the motor. A screw-in nut is required to use that; years ago, Branchlines sold a screw-nose ring for those motors.

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Mon Oct 14, 2013 10:32 am

Thanks again Nigel. Very useful information, even if only marginally useful for 4mm scale!

Possibly the cheap 12v motor could be used in multiple, in difficult situations - rather like the Nigel Lawton motor applications on the CLAG site, or just linked together by spur gears.

My gloat box still has a few other motors to get rid of in one way or another, so I won't be needing to buy any new ones just yet.

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Mon Oct 14, 2013 11:00 pm

I was feeling very disjointed and uncoordinated today - a dangerous time to be doing any modelling. Don't know why - it just happens from time to time! :?

Nevertheless, I plodded on with a few "safe" jobs on the loco.

I have now started preparation for painting on the inner chassis and gearbox - easier to start now than when it is all assembled. The brass inner chassis has been dunked in metal blackener which worked OK - much better than dunking it in my tea and drinking the metal blackener, which might easily have happened given the state I am in. :shock:

For the few additions to the chassis yet to be undertaken, I can easily remove any of the blackener for soldering etc. later if required. The main addition will be the brake gear, which I can't really do well until the chassis has been fully assembled, complete with wheels. I also put some etch primer on the more exposed parts of the gearbox. Most will be well hidden, but better safe than sorry.

Four holes were drilled in each wheel. I did this by eye, making a reasonable job of it. The plastic in the Gibson wheels is very easy to drill through.

I then went back to soldering. :shock: The handrails were cut, bent and soldered into place either side of the doors. I also added 4 bits of scrap brass rod at the front of the cab to act as guides for locating the bonnet. Holes are already there in the etch. I also added the exhaust pipe. I tinned it on the side that would go next to the cab front and soldered it in place, adding a large blob of solder at the bottom (which will be hidden by the bonnet), just for luck. I then cut out a D shaped slot in the bonnet so I can still fit the bonnet up against the cab front. This is how it seems to have been done on the prototype.

Finally, I cut a piece of code 40 bullhead rail to represent the channel along the top of the bonnet. This channel was used on the prototype to hold the bonnet flaps in place when they were opened for maintenance purposes. The photo below shows these additions. I must admit the bonnet now looks awful in the photo. :shock: It really isn't anything like that bad in reality, I promise - and what stray solder there is will easily be cleaned up - honest :geek:

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Apart from the brake gear and the derail brackets, there is little more detail soldering to do. Most of the other small bits will be glued in place, I think. I have yet to decide how to affix the roof to the cab. I would like it to be removable, if possible, so that I can easily get inside the cab to add as much detail as possible.

The main priority now is to get the chassis up and running. Only then can I finally decide if the Sagami is up to the job. Little more can be done to the rest of the loco until that is all sorted.

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Terry Bendall » Tue Oct 15, 2013 6:41 am

Armchair Modeller wrote: I have yet to decide how to affix the roof to the cab.


An idea that I have seen for the cab roof on steam loco models is to bend some thin strips of 5 thou brass or nickel silver in an L shape and solder then to the inside of the roof so that they hold it in place by the springiness of the metal. That means it can be removed easily. Another method is to use something like PVA glue which will have sufficient grip to hold the roof but it could be removed with a bit of gentle levering if needed. You might want a bit of beading round the edge to hide any gaps.

Terry Bendall

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Tue Oct 15, 2013 9:21 am

Thanks Terry - they both sound like good ideas. :thumb

I have plenty of time to think about it, as adding the roof will necessarily be just about the last thing I do on the model.

My main concern with a loose roof is that the cab sides are quite weak, as they are predominantly a half-etch. The cab could easily be damaged in ordinary handling, never mind falling on the floor. Had i done it again, i would have soldered brass strips inside the cab sides before I assembled the cab, to make things much more robust. Unfortunately, I think it is too late now, as the heat required would likely melt the other joints.

Soldering the roof would add considerably to the strength. If I do that though, I can't see a way of having a full cab floor, since you really need to be able solder the roof on from inside the cab - catch 22?

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby nigelcliffe » Tue Oct 15, 2013 2:04 pm

Armchair Modeller wrote:Thanks Terry - they both sound like good ideas. :thumb

I have plenty of time to think about it, as adding the roof will necessarily be just about the last thing I do on the model.

My main concern with a loose roof is that the cab sides are quite weak, as they are predominantly a half-etch. The cab could easily be damaged in ordinary handling, never mind falling on the floor. Had i done it again, i would have soldered brass strips inside the cab sides before I assembled the cab, to make things much more robust. Unfortunately, I think it is too late now, as the heat required would likely melt the other joints.


I'd add some strength by careful use of the iron. A few tricks which may help...
- First use a lower temperature solder for the strengthening strips.
- Use of damp tissue paper or a damp cloth (very damp, and a fair bit of tissue) can act as a useful heat sink. So, protect the majority of the cab corner joints with damp tissues, that will stop any melting of solder spreading very far.
- For the strengthening, Ideally I'd make and bend a complete rectangle of etch offcut as a good fit inside the cab. If that proves impossible, make two "U" pieces which almost butt where they meet. Tack the strengthening piece near middle of the wall, repeat on other walls. Then tack again halfway between middle and corner, repeat all round. Finally solder from the "L halfway" into the corners (do carefully, quickly for the soldering, then allow decent time for cooling).

Alternatively, build a frame below the roof which locates the roof accurately against the sides. A small bent part piece in the middle of each edge should be sufficient for alignment. I think the "springs" for the corners are still desirable, though the thinnest springy wire will be sufficient.


- Nigel

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Tue Oct 15, 2013 3:13 pm

Many thanks again, Nigel. I shall seriously consider your suggestions. :thumb

Had I followed the instructions, the cab would already be soldered to a floor plate with a big hole in it to allow the motor to intrude a long way into the cab. With the roof soldered on too, these would help a lot with the strength of the cab - but not help much if the model was picked up by placing fingers in the middle of the sides, which seems the "natural" way of doing it.

One other possibility for the cab would be to solder the roof on and solder strengthening bars further down - say, just below the windows and at floor level. The floor level ones could have holes with nuts soldered on to make the cab removable at the base.

Whatever I do, it has to look neat - and I have to be able to access the inside of the cab for detailing and painting. I reckon I have a week, at least, to think about it before I have to commit to anything.

A bit more time yet to consider the options!

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Wed Oct 16, 2013 7:51 pm

Not much to report today, but I thought it best to show that I have not yet given up - not that this would ever be likely ;)

The England football match yesterday was too difficult to miss, so very little got done in the way of modelling. This evening though, I have painted the inner frame and parts of the gearbox in dark grey Humbrol matt enamel. These parts are neither particularly vulnerable to wear, nor very visible, so brush painting was deemed to be adequate for the job. Once this has dried thoroughly, I can begin the final assembly of the working chassis. Further painting and touching up will be required once the brake gear, wheels and axles, pickups and a few other details have been added.

I have also been studying photographs to see what else I need to do in the way of detailing. Through Google, I found the following links, which are likely to prove very useful.....

http://www.rmweb.co.uk/community/index. ... 7mm/page-3 - a fascinating photo of a chassis under construction and further down, a side elevation of the radiator and fan arrangement, which gives clues about exterior fittings too.

http://homepage.ntlworld.com/old.origin ... CTIONS.pdf – Old Originals Gauge One model instructions with lots of useful detail photos and information.

I also found a reasonable number of photos of real locos. Some additional details have come to light including the radiator supports, which are attached to the front buffer beam. I am also now unhappy with the radiator and fuel filler cap castings provided in the kit. I am likely to make my own. Working out what my individual loco should or should not have is proving interesting :? Rule 1 will definitely apply!

Returning to the cab strengthening issues discussed yesterday, I have now ordered some brass sheet. I have also ordered some L section brass to make up the vertical parts of the derail bars, which are attached to the front and read buffer beams. Etches are provided in the kit, but the L section brass will look much cleaner and sharper.

So, it is back to the chassis tomorrow........ :D

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Fri Oct 18, 2013 3:57 pm

Progress has continued with the assembly of the chassis. This has proved a little problematic, but nothing that can't be overcome, I hope! I didn't have time to do an update last night, but made reasonable progress.

I assembled the floating (rear) axle first, making sure that the axle was slightly on the loose side in the bearings. It was a little fiddly to get the gear in the right place. I then put the wheels on using the GW wheel press. I quickly found that the axle was slightly oversize (about 1mm), so the wheel press didn't push the wheels fully home. I could have adjusted the press, but decided to try adjusting the wheels by hand, using a back-to-back gauge, gently revolving the wheels one by one, as I pressed them gently inwards. This worked, but one wheel disappointingly now has just a very slightly wobble.

I then tested the chassis with just the one axle. The motor comfortably turned the axle and the gearbox. Everything worked fine!

I adjusted the axle length for the fixed (front) axle and then assembled it in the chassis with the gear and wheels. Again, the motor turned everything - however, the gear did seem a little loose on the axle. When I put a little pressure on the wheels with my fingers, the gear definitely slipped. This was quite a contrast to the one on the rear axle, which was a very tight fit.

I have now carefully disassembled the front axle and reassembled it with 2 washers and a spot of epoxy adhesive around the gear. I have also glued some double-sided copper clad sheet onto the chassis sides, ready for attaching pickups.

The epoxy was left to set overnight. This evening, I will check that everything is OK. I can then put the wheels back on and test again with power on.

Good news is that the motor seems to have substantially more than adequate power to turn the wheels. The pickups will add to the friction, of course. I will take care to make sure they don't act too much like brakes though.

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Mon Oct 21, 2013 12:04 pm

Walking and working are interrupting play at the moment. On my most recent walk, I managed to get sprayed by a weedkilling train at Shipley Gate, on my way west to Duffield and Derby. That should keep the nits at bay for a while ;)

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My experiment with epoxy adhesive was not a great success, I am afraid. I had been unable to get the epoxy sufficiently far down into the very tight gap between the washers and the loose spur gear to attach it permanently to the axle. :?

My next crazy scheme was to dismantle things again and use subtlety, rather than my more normal gung-ho tactics. I suppose I should just have rung up Mr High Level and asked for another spur gear, but I don't like giving up easily!

Instead, I separated out the spur gear again and gently rubbed a thin layer of cyano adhesive around the inside of the hole in the spur gear with a pin, soaking off the excess into some tissue paper. After allowing a couple of applications to set, the gear was significantly tighter on the axle. I then reassembled the axle and the gear, putting just a tiny touch of cyano on the axle/gear interface. When I checked this lunchtime, the gear is solidly stuck to the axle, but the axle is free to revolve in the chassis. RESULT! :D

Unfortunately, I only expect to make very slow progress this week, as I have a lot of work on my plate. In any case, I expected things at this stage to slow down. Looking carefully at illustrations of the tiny details and adding them to the model is always going to be much slower than putting the bigger components together.

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Sat Sep 26, 2015 7:17 pm

I am just reading through all the stuff I put on my Workbench Forum and noticed that this thread never got finished. I doubt if anyone was holding their breath for the next instalment. Nevertheless, it is only fair to round it off. Truth is, I never got any further with the kit. In the end I decided I was unhappy with the idea of a motor sticking into the cab - especially with all that fresh air under the bonnet. I was a bit uncomfortable with the compensation arrangements too - but that is probably just me being too fussy. So, the chassis was never finished and neither was the body.

Plans are afoot to build a new chassis - in fact several, as I have a few 4-wheeled chassis to construct for different locos and other eclectic motive power. Some of these have awkward wheelbases, so no commercial chassis or power bogie would suit, even if I were inclined to try them. Building up some experience in scratchbuilding chassis will be a useful and (hopefully) rewarding exercise. I shall begin by redoing the chassis for my Nonneminstre Models Hibbard Planet shunter (new topic), which has a few special problems to address. The Ruston is probably next - but I will start a new topic to cover this when I make a start.

Will he ever finish anything, you may well ask - well, I do hope so! ;)

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Wed Apr 12, 2017 8:34 pm

Well, it's been a long time, but I am finally getting back to finishing this project off. RobM is largely to blame, having gently chided me for not finishing it, whilst getting his own built and running in a matter of a few weeks ;)

Having brushed off the cobwebs, the body looks pretty reasonable, so well worth finishing. It was the chassis I had concerns about. I have a deep suspicion about rocking axle 3-point suspensions, for reasons espoused elsewhere. I also wanted to get the motor out of the cab, so I could do a good job of the interior. OK, I'm being fussy, but that's me! I thought long and hard about how to overcome the issues - 3 1/2 years to be precise. Not that I was just thinking about the Ruston. My tramway has a crying need for odd, interesting and obscure small 4-wheeled vehicles of many kinds. I was trying to think in a more general way about small chassis design. Most would have a very short wheelbase - the Ruston, for example, is a mere 21mm.

Thinking through the options...

1. Conventional 3-point suspension

As with the original chassis, a lot of space is occupied by the pivot point and the gears necessary to link up the axles. The pivoting axle is unstable unless weighed down heavily. Desirability - over my dead body!

2. Sprung Suspension

In general, I think I would prefer a sprung setup with CSBs. Squeezing a gearbox on each axle, plus connections to a motor would probably take up a lot of space though.

3. Rigid chassis with a bit of give.

Would probably work, but there might be adhesion issues without a lot of weight - which there is little room for.

4. 3-Point Suspension with compensation beam along one side of the chassis (Preferred Option)

This would have the axles held rigidly on one side. The axles would be connected by gears down this side of the chassis. That leaves a lot more room for other things in-between the wheels.

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There are other options, like powering one axle only, or even one motor per axle. Option 4 is the one I feel happiest with though. Remember, it is not just for the Ruston, but potentially for lots of other victims too.

That's the general theory, anyway. Not my idea by the way. So far, I have been cutting brass for frames. Old-fashioned piercing saws and drilling for me. No new-fangled etching or 3D printing. Actually, that's not quite true. Despite having rigidly-held axles I shall be using High Level Minibloxes to hold the wheels in place. Bizarre, but true. More of that later.

I have made a simple jig to align the hornblocks, rather like that on my Frateschi G-8 bogie construction. There are 3 layers of brass sheet, one for each frame plus one for the compensation beam.

a-DSCF4928.jpg
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The brass is deliberately much longer than the loco frames so I can use jigs outside the chassis to align everything when I do the final assembly.

Incidentally, this book is great source of information and photos for anyone making a model of the Ruston 48DS

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I will be building this chassis in parallel with the Frateschi G-8, as the early stages of construction will be similar. Next job is to cut out slots for the hornblocks. As with all my work, this is experimental, so I shall be as surprised as anyone if it really works ;)

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Andy W
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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Andy W » Wed Apr 12, 2017 9:56 pm

Another version of your 3 point system would be not to use a beam, but to pivot the chassis side itself. Apologies if you've already mentioned this.
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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Wed Apr 12, 2017 10:13 pm

Thanks Andy. That is indeed another option - and I had not mentioned it. One snag I can see (if I am visualising your idea correctly) is the need for a pivot rod right across the middle of the chassis from the opposite frame. That would limit what else I could put low down within the frames. By putting a frame next to the compensation beam, the pivot need not cross the chassis from one side to the other.

One thing I didn't mention in my last post was the advantage of building new frames to P4 standards. This also gives a bit more space between the frames that can be used to advantage. The original chassis is quite narrow between the frames. I reckon I could get around 4mm extra just by pushing the underframe sides out to the max - less the narrow width of the compensation beam.

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby RobM » Thu Apr 13, 2017 10:31 am

All sounds good Richard.
Armchair Modeller wrote:The original chassis is quite narrow between the frames. I reckon I could get around 4mm extra just by pushing the underframe sides out to the max less the narrow width of the compensation beam.

No doubt you have thoughts on the pick ups.
Rob
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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Thu Apr 13, 2017 3:56 pm

Rob,

I do have ideas, thanks. Easier to explain when I get that far.

Looking at the diagram again, I realise I got the compensation beam in the wrong place - :shock: it should be on the outside of the frame, like this...

a-Chassis-Concept-corr.jpg
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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby grovenor-2685 » Thu Apr 13, 2017 7:14 pm

it should be on the outside of the frame, like this...

Why?
I think your first version is better, the beam needs to sit over the bearings, which are usually fitted to the inside of the frames, also the beam inside will not be visible so does not need to be disguised as some prototypical part.
Regards

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Thu Apr 13, 2017 9:53 pm

grovenor-2685 wrote:
it should be on the outside of the frame, like this...

Why?
I think your first version is better, the beam needs to sit over the bearings, which are usually fitted to the inside of the frames, also the beam inside will not be visible so does not need to be disguised as some prototypical part.
Regards


Thanks for the query, Keith :thumb

Truth is the Ruston has deep outside frames as part of the bodywork, so everything inside the wheels will be very well hidden. As for the bearings, they will be an integral part of the compensation beam. All will become clear in a day or three (day two being a 20 mile hike across the Dark Peak).

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Enigma » Wed Apr 19, 2017 9:42 am

Have you seen this?

http://www.rmweb.co.uk/community/index. ... ers-guide/

A thread started by the man himself. There are also other threads on RMWeb all about building the 48Ds. May be some useful info in there for you.

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Wed Apr 19, 2017 12:18 pm

Enigma wrote:Have you seen this?

http://www.rmweb.co.uk/community/index. ... ers-guide/

A thread started by the man himself. There are also other threads on RMWeb all about building the 48Ds. May be some useful info in there for you.


Thanks for the link. I have been following it since its inception. It includes one or two photos I had not seen before. I had more or less completed the body on mine long before that topic was started, sad to say!

The chassis is progressing and I should have a detailed report soon, with luck. I pushed myself much harder than expected on Saturday's walk, doing significantly greater mileage and ascent than planned. I found it challenging to get my modelling act together again afterwards!

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Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Sun Apr 30, 2017 8:27 pm

11 Days later - at last, a further progress report! I have in fact been doing little bits here and there odd days for a while - seriously interrupted though by some 2mm modelling in preparation for a 2mm area group meeting. Got to keep them happy as well! I only got far enough to show what I have done with the Ruston in the last couple of days.

After cutting the frames and compensation beam to shape, the next job was to solder on the hornblocks. I used the wooden jig made previously to locate each frame individually. One frame had to be done upside down in the jig to get the hornblocks on the correct side, so I packed the back with some PCB, which just happened to be the correct depth (see photo).

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It was best to do the compensation beam soldered with the outside facing up so that the solder was all on the front. I didn't want any on the back as it would need filing off to get a close fit with the frame. It is perhaps wrong to call it a compensation beam - perhaps rocking frame would be better?

Next, I soldered the fixed frames together with PCB spacers. For this I used two 2mm Finescale frame jigs - as in this photo.

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The frames were soldered together on a flat surface. This was the end result, after cutting off the ends,with the other dummy frames from the Judith Edge kit at the top...

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With my inner frames and the Judith Edge outers temporarily assembled, this is what a side view looked like...

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Everything was going well at this stage, so I thought - so I sat back and browsed through the Ruston book I mentioned in an earlier post. One point I noticed pretty soon was that only the very early locos were fitted with 2ft 3in wheels, as supplied with the kit. The vast majority were 2ft 6in. That set me thinking. A set of 9mm wheels would come in very useful for other projects with more visible wheels. In the end I decided to fit some Ultrascale 2ft 9in wheels instead. Sounded good at the time, but I quickly realised I would have to shave 1mm off the top of my inner frames for the buffers to be at the right height. So, I set to work with a piercing saw and fortunately, the trimming exercise proved moderately easy. It also proved that the soldering was good!

So here is an upside down view of the outer frames with my inside frames mounted inside. The rocking frame should be a lot tighter to the fixed frame, but I separated them slightly to make the components clearer in the photo. I have one slight adjustment to do as one of the frame spacers is slightly in the way of the bolt hole for fixing the inner chassis to the rest of the loco. I will have a go at that later.

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To answer Keith's query about the position of the compensation beam, I suspect I am using the wrong name which led to the confusion. It is best to have the rocking frame on the outside of the fixed chassis parts as this leaves the inside of the fixed part unobstructed. I can fix the motor mount and other bits to something rigid without having to worry about moving parts getting in the way. The hornblocks will be packed with shims so they don't move in the hornblocks. I am only using hornblocks because it makes the wheel sets easy to fit or remove from the chassis.

My Sagami motor will be mounted vertically under the bonnet. This will be connected by a 10:1 worm gear to a lay shaft running along the inside of the fixed side of the chassis. Power will be transferred to each axle by 1:14 gears. That gives a rather high ratio of 1:140 overall, but hey - these things were only supposed to do 7mph max! I was hoping to use 2 lots of 1:10, but the pinion wheels are too small for a 2mm axle. The whole lot will be on a subframe so that I can carefully adjust the position before permanently fixing everything in position. At least, that is the plan... :shock:

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steamraiser
Posts: 377
Joined: Thu Dec 31, 2009 4:49 pm

Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby steamraiser » Fri Aug 25, 2017 8:28 am

I have fitted a Mashima 1015 to my 48DS in place of the 1220.
This gives me room to fit a Zen Nano "stay alive" package in the cab.
So I opted for a Mashima 1015 from Chris at HL.

 Here is the chassis fitted with the new 1015.
P1060407a.jpg

The red yellow wires have only been added for testing on DC.
 
Here is a shot with the 1015 fitted and the 1220 alongside in comparison.

P1060408a.jpg

On measuring the 1015 the cross section appears to be the same as the 1220, however crucially in my case it is 5mm shorter.
Chris G warned me that the motor mounting holes in the gear box would need easing, which proved to be the case.
A few minutes work with a rat tail file.
 
Here is a shot showing the "stay alive" package glued to the cab back and one of the drivers feet.
P1060410a.jpg


 
And finally with the body screwed on, well four out of the six screws.
P1060414a.jpg

You can just see the drivers arm.
 
The loco runs quite nicely on my test track with the "stay alive" enabling smooth slow starts and stops.
Just final detailing and touching up to do.
 
Now can I fit the same DCC package in my Planet?

Gordon
 
Gordon

Armchair Modeller
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Joined: Thu Jan 06, 2011 7:34 pm

Re: Here We Go... Judith Edge Ruston 48DS Kit

Postby Armchair Modeller » Fri Aug 25, 2017 9:41 am

That looks great, Gordon. Will you be bringing it along to Scaleforum?


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