High Level chassis kit for Class 03/04

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John McAleely
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High Level chassis kit for Class 03/04

Postby John McAleely » Wed Mar 16, 2011 11:15 pm

My first attempt at building a loco chassis will be the High Level class 03/04 chassis kit:

photo 1.jpg


Here it is laid out on my workbench. In addition to the kit itself, I've needed to buy:

Wheels
Crankpin Parts
M2 Nuts & Bolts
Additional Crankpin bushes
Pickups

In order to get the chassis off to a good start, I took up a recommendation to try out the Missenden Abbey modelling weekend. So what you see was posed on Friday evening, after setting up.

An important goal for me is that the chassis works. Other goals I considered (looks, fidelity to a prototype, pairing it with a finescale body) are explicitly secondary this time around.

I chose this kit because I could be sure that it was designed for P4/compensated construction, and I wouldn't need to design any part of the mechanism. Getting it to work will be challenge enough :-) As such, I'll build it pretty much as the thorough instructions suggest.

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Dave K
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Re: High Level chassis kit for Class 03/04

Postby Dave K » Thu Mar 17, 2011 8:04 am

John,

What type of body are you using
:?:

Rustyrail

Re: High Level chassis kit for Class 03/04

Postby Rustyrail » Thu Mar 17, 2011 9:31 am

Very interesting John... keep posting!

Cheers
Simon

craig_whilding
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Re: High Level chassis kit for Class 03/04

Postby craig_whilding » Thu Mar 17, 2011 10:06 am

dave k wrote:John,

What type of body are you using
:?:

D2264 shown in the photo is an older Bachmann 04. I had wondered as the new 03 needs the chassis modifying to avoid the metal running plate.

martin goodall
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Re: High Level chassis kit for Class 03/04

Postby martin goodall » Thu Mar 17, 2011 10:44 am

Rustyrail wrote:Very interesting John... keep posting!

Cheers
Simon


Me, too! I have one of these kits to build when I get 'a round tuit', so I hope to pick up some useful hints and tips.

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John McAleely
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Re: High Level chassis kit for Class 03/04

Postby John McAleely » Fri Mar 18, 2011 12:06 am

craig_whilding wrote:D2264 shown in the photo is an older Bachmann 04.


I'll take your word for it. I acquired it as the only suitable secondhand model in my local model shop :-) Putting aside a perfectly functional 00 chassis marks a turning point in my modelmaking, I feel.

The kit instructions recommend assembling the step assemblies first. These will be epoxied onto the Bachmann body, and then will form the mounting point for the chassis proper.

By friday evening, I'd assembled the front step box:

IMG_4207.jpg


You can tell I'd not had any tutoring in soldering (Specifically sweating together sheets of material).

By the end of day one, I'd assembled both sets of steps, and a start on the chassis can be seen in the foreground:

IMG_4208.jpg


In the photo I've not attached the steps - merely placed them under the body for photographic effect.

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John McAleely
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Re: High Level chassis kit for Class 03/04

Postby John McAleely » Sat Mar 19, 2011 1:41 pm

For the next bit, being at Missenden really helped. The instructions tell you what order to assemble the coupling rods, but the actual technique of sweating them together, and then filing away the rough surface was shown to me by the course tutor. Also the sequence of building with the jig - do the coupling rods first, and then use this to set the jig up to build the chassis was suggested by one of the other more expert folk in the room. Perhaps I would have figured all that out, but certainly not so quickly, or executed it so well without the help.

IMG_4209.jpg

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John McAleely
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Re: High Level chassis kit for Class 03/04

Postby John McAleely » Sat Mar 26, 2011 11:56 pm

So, after assembling both sets of coupling rods, it was time to use the jig to assemble the chassis box itself.

After 2 days of concentrated modelling, here's what I had achieved:

IMG_4213.jpg


I was incredibly pleased with my progress, and the secret was certainly the tutoring and company at Missenden.

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John McAleely
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Re: High Level chassis kit for Class 03/04

Postby John McAleely » Sun Mar 27, 2011 12:05 am

It already seems like some time ago I was at Missenden, but it can't be very long - there has not been a CHEAG meeting yet :-)

Today I took advantage of the exhibition at Ally Pally to buy a few more tools I needed to progress my kit. Not least was a new soldering iron, since mine had fried itself during the weekend at Missenden.

Getting back, I've done some more this evening. The chassis has lots of little details added, and the compensation beam is in place. I've also started assembling the gearbox:

Chassis2.jpg
Chassis2.jpg (45.65 KiB) Viewed 9736 times


Chassis3.jpg
Chassis3.jpg (46.62 KiB) Viewed 9736 times


Now, I have a question. I've been cleaning up the soldered chassis with a scrub under cold water at the end of each day. The instructions note that the gearbox should be 'cleaned of flux with household cleaner'. Is the water scrub I've done likely to be sufficient? I've seen no evidence of the green oxidation (?) I saw on my earlier kit which I didn't clean at all, so I'm guessing the water scrub has got the flux off so far?

If the scrub isn't likely to be sufficient, which household cleaner is it alluding to?

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Flymo748
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Re: High Level chassis kit for Class 03/04

Postby Flymo748 » Sun Mar 27, 2011 8:04 am

John McAleely wrote:It already seems like some time ago I was at Missenden, but it can't be very long - there has not been a CHEAG meeting yet :-)


First Thursday of the month :-)

As I mentioned, I'm afraid that I won't be there for April as I'm double booked with the Stonewall Fundraising Dinner. I will look forward to catching up with you and the chassis kit soon though. You're making good progress!

John McAleely wrote:Now, I have a question. I've been cleaning up the soldered chassis with a scrub under cold water at the end of each day. The instructions note that the gearbox should be 'cleaned of flux with household cleaner'. Is the water scrub I've done likely to be sufficient? I've seen no evidence of the green oxidation (?) I saw on my earlier kit which I didn't clean at all, so I'm guessing the water scrub has got the flux off so far?


If you've switched to a liquid flux, like the one that you were using at Missenden, then not only will your soldering be neater (shows a touch of prejudice!) but there will be less cleaning up needed. I'm certain that the nasty green clagginess shown on your wagon chassis was due to the Powerflow paste flux that you were using. Was that a pot of it still lurking in the background in your picture???

Using a liquid flux, a good rinse in lots of water may be sufficient. You may also want to use Carrs Neutralising Rinse as well just to make sure.

John McAleely wrote:If the scrub isn't likely to be sufficient, which household cleaner is it alluding to?


There are a couple of different routes on this. Some prefer a cream cleanser type product like Cif, and others use a "Shiny Sinks" sort of thing, which I believe is more water-like. David Brandreth was using the latter at Missenden and the results were effective, but I didn't see what it was actually like.

Either way, whatever is under your kitchen sink will probably do the trick, as long as you make sure to wash it all off scrupulously.

HTH
Flymo
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Trevor Grout
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Re: High Level chassis kit for Class 03/04

Postby Trevor Grout » Sun Mar 27, 2011 8:53 am

Flymo748 wrote:
John McAleely wrote:It already seems like some time ago I was at Missenden, but it can't be very long - there has not been a CHEAG meeting yet :-)


First Thursday of the month :-)

As I mentioned, I'm afraid that I won't be there for April as I'm double booked with the Stonewall Fundraising Dinner. I will look forward to catching up with you and the chassis kit soon though. You're making good progress!

John McAleely wrote:Now, I have a question. I've been cleaning up the soldered chassis with a scrub under cold water at the end of each day. The instructions note that the gearbox should be 'cleaned of flux with household cleaner'. Is the water scrub I've done likely to be sufficient? I've seen no evidence of the green oxidation (?) I saw on my earlier kit which I didn't clean at all, so I'm guessing the water scrub has got the flux off so far?


If you've switched to a liquid flux, like the one that you were using at Missenden, then not only will your soldering be neater (shows a touch of prejudice!) but there will be less cleaning up needed. I'm certain that the nasty green clagginess shown on your wagon chassis was due to the Powerflow paste flux that you were using. Was that a pot of it still lurking in the background in your picture???

Using a liquid flux, a good rinse in lots of water may be sufficient. You may also want to use Carrs Neutralising Rinse as well just to make sure.

John McAleely wrote:If the scrub isn't likely to be sufficient, which household cleaner is it alluding to?


There are a couple of different routes on this. Some prefer a cream cleanser type product like Cif, and others use a "Shiny Sinks" sort of thing, which I believe is more water-like. David Brandreth was using the latter at Missenden and the results were effective, but I didn't see what it was actually like.

Either way, whatever is under your kitchen sink will probably do the trick, as long as you make sure to wash it all off scrupulously.

HTH
Flymo


And make sure that you use a bowl, lest anything might fall of and make a break for the plug hole!

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David B
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Re: High Level chassis kit for Class 03/04

Postby David B » Sun Mar 27, 2011 9:29 pm

As Paul said, I use Shiny Sinks and give the piece a fairly stiff brush. You must keep the plug in the hole or use a bowl (as mentioned above). Then, rinse thoroughly in clean water, using a brush to get everything - flux, debris and cleaner - off. I prefer warm water as it is more comfortable to use and the heat helps to dry the model afterwards. Clean after each session and sometimes during as well. Cleanliness with soldering - before, during and after - is important as you may recall from Tim Watson's demonstration.

Other products I know some people use are Cillit Bang and Vaikal. Similar cleaners can also be used, but always make sure you rinse the model thoroughly afterwards. Once dry, clean up your soldering as well.

Keep at it. I am enjoying following your progress.

David

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John McAleely
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Re: High Level chassis kit for Class 03/04

Postby John McAleely » Sun Apr 17, 2011 10:03 pm

Flymo748 wrote:If you've switched to a liquid flux, like the one that you were using at Missenden, then not only will your soldering be neater (shows a touch of prejudice!) but there will be less cleaning up needed. I'm certain that the nasty green clagginess shown on your wagon chassis was due to the Powerflow paste flux that you were using. Was that a pot of it still lurking in the background in your picture???


Well spotted! I am indeed still using the paste from time to time - I find the tackiness useful sometimes. The brown blob in the same picture is a liquid flux (thanks for the loan previously!), and I use that most of the time. Either way, I've been scrubbing regularly with water and a toothbrush, and there is no sign of green oxidisation. I was curious why the instructions might have stressed this point for the gearbox.

No pics for an update today, but I would like to thank Terry Bendall and Mike Ainsworth for providing useful advice at today's Epsom show (great show too!). I'm between meetings of CHEAG, and managed to get some tips on gearbox smoothness and the tolerances I can expect in various places.

So the chassis now has two axles with wheels on, and a gearbox which shows signs (on second try) of running smoothly. I may be able to put up some more pictures later in the week.

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Flymo748
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Re: High Level chassis kit for Class 03/04

Postby Flymo748 » Mon Apr 18, 2011 6:48 am

John McAleely wrote:
Flymo748 wrote:I'm certain that the nasty green clagginess shown on your wagon chassis was due to the Powerflow paste flux that you were using. Was that a pot of it still lurking in the background in your picture???


Well spotted! I am indeed still using the paste from time to time - I find the tackiness useful sometimes. The brown blob in the same picture is a liquid flux (thanks for the loan previously!), and I use that most of the time. Either way, I've been scrubbing regularly with water and a toothbrush, and there is no sign of green oxidisation.


A good scrub should certainly stop that nasty green growth appearing. I usually try and clean my work up after every two or three modelling sessions with a good swill of Acidip and then a dip in plain water in the utrasonic cleaning tank. But that is using liquid fluxes, and if I was using a paste flux I wouldn't be leaving it that long to set solid on the model.

John McAleely wrote:I was curious why the instructions might have stressed this point for the gearbox.


Possibly because there is no way that you want any nastiness later building up inside the gearbox with all the gubbins in place. Also, with steel shafts taking the various gears, the potential problems are far more serious in their impact.

John McAleely wrote:I'm between meetings of CHEAG, and managed to get some tips on gearbox smoothness and the tolerances I can expect in various places.


I'll certainly try and get up to the May meeting. It's my wife's birthday though, so I have to see if I get a pass out ;-)

It's certainly very useful to have an area group that you can bounce ideas off. I think that Martin suggested that the next session would have a theme of painting and lining, so I might have to think what to bring along. That subject is not one of my strengths.

John McAleely wrote:So the chassis now has two axles with wheels on, and a gearbox which shows signs (on second try) of running smoothly. I may be able to put up some more pictures later in the week.


Yes please, I'll look forward to seeing the progress :-)

Flymo
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John McAleely
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Re: High Level chassis kit for Class 03/04

Postby John McAleely » Sat Apr 23, 2011 10:56 pm

So, lets start with the two wheel version:

HighLevel03-1.jpg
HighLevel03-1.jpg (41.87 KiB) Viewed 9467 times


And the brakegear, which I worked on today:

HighLevel03-2.jpg
HighLevel03-2.jpg (48.51 KiB) Viewed 9467 times


And, for the finale, an assembled chassis on my rolling road:

HighLevel03-5.jpg
HighLevel03-5.jpg (50.31 KiB) Viewed 9467 times


And it does work! Although it certainly needs some debugging. When the coupling rods are on, it has a distinct bind. Without the rods on, it runs well, although I might have eliminated the sidelplay on the driven axle too keenly - the rotation is smooth, but seems very stiff compared to the other two axles.

Any thoughts on finding and fixing the issue when the coupling rods are on?

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Re: High Level chassis kit for Class 03/04

Postby craig_whilding » Sat Apr 23, 2011 11:18 pm

John McAleely wrote:Any thoughts on finding and fixing the issue when the coupling rods are on?

Its probably a quartering issue or a wonky crankpin as the jig should have eliminated other issues.

Best test is running the chassis up and down a piece of track under gravity by tilting it when the motor is removed. You'll get more chance to note the bind. Is it ok with the rods only attached to two axles is then the first to test before checking the 3rd set of wheels.

The snag with the High Level chassis as designed is you can't drop the complete wheelset out in one go when it is correctly quartered though :(.

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Re: High Level chassis kit for Class 03/04

Postby Flymo748 » Sun Apr 24, 2011 6:55 am

John McAleely wrote:
HighLevel03-5.jpg


And it does work! Although it certainly needs some debugging. When the coupling rods are on, it has a distinct bind. Without the rods on, it runs well, although I might have eliminated the sidelplay on the driven axle too keenly - the rotation is smooth, but seems very stiff compared to the other two axles.

Any thoughts on finding and fixing the issue when the coupling rods are on?


See if you can run it very slowly until it stalls where it binds. Then stop the power and have a good peer at each crankpin.

Look *very* closely at the clearances on either side of the crankpin. The pin should be sitting centrally in the hole. If it isn't then, tweak the quartering slightly. We know that the rods are the correct length, and match the axle spacings as Craig says, for it was set up in a jig.

An alternative may be that the holes in the coupling rods are actually too tight a fit, and you need a fraction of clearance easing into them. This was the issue the Tim Watson found on my Y14.

But check the quartering first. Removing metal is a one-way course of action!

Flymo
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John McAleely
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Re: High Level chassis kit for Class 03/04

Postby John McAleely » Sun Apr 24, 2011 9:41 am

Would the fact that I users GW Models jig for the quartering eliminate that as a probable cause?

Peering at the chassis, I'm suspicious of the crankpins - one in particular does not look square. After that, I'm tempted to loosen out the crankpin holes - one rod in particular was always a very exact fit on the jig.

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Re: High Level chassis kit for Class 03/04

Postby John McAleely » Sun Apr 24, 2011 4:01 pm

OK, so I've had two problems to troubleshoot today - the overall rolling resistance of the chassis (with the rods off), and the bind with the rods on.

Taking the first, I adjusted the washers (thinned one slightly) on the driven axle, and the chassis now runs freely. One down!

Looking at the bind, I've checked the quartering with my gw models jig for each axle, and it seems fine. I've looked at the crankpins, and with some minor tweaks, satisfied myself they are at 90 degrees to the wheels/axles through their revolutions.

Taking the advice of looking at pairs of axles in turn, I've converted the chassis to an 0-4-0:

HighLevel03-1.jpg
HighLevel03-1.jpg (59.15 KiB) Viewed 9425 times


And can observe the bind even here. Now, question one. When I run the chassis under finger pressure on my track, I can generally run through the bind, and (perhaps) it doesn't always happen. If I stop the chassis at a free running moment, and then (holding the wheels steady) pull at the rods with my tweezers, I can feel a tiny amount of give. If I let the chassis bind, and then repeat the experiment, at least one of the rods will have no give at all with an attempt at wiggling it with my tweezers. Am I right in thinking that is wrong? And that there should be always a teeny-tiny amount of give?

Second question. The chassis specifies that you need to buy extra 'long' crankpin bushes to the standard kit. This makes sense if each axle needs one. However, that means there is what looks like a lot of sideplay on the two front axles. Is that right? In the pics below, I've mounted one axle as I believe the kit intends, and one with a much shorter bush. Which should I be trying to use? (FWIW the chassis is more likely to bind with these short bushes in use).

Lots of sideplay:
HighLevel03-2.jpg
Large Sideplay
HighLevel03-2.jpg (38.59 KiB) Viewed 9425 times


No sideplay:
HighLevel03-3.jpg
No sideplay
HighLevel03-3.jpg (42.34 KiB) Viewed 9425 times

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Flymo748
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Re: High Level chassis kit for Class 03/04

Postby Flymo748 » Sun Apr 24, 2011 6:58 pm

John McAleely wrote:Would the fact that I users GW Models jig for the quartering eliminate that as a probable cause?

Peering at the chassis, I'm suspicious of the crankpins - one in particular does not look square. After that, I'm tempted to loosen out the crankpin holes - one rod in particular was always a very exact fit on the jig.

Hi John,

I wouldn't say that it will eliminate it entirely - I know how cack-handed I can be when using any sort of jig :-/

However it is very likely that it is not a major cause of error. If you have a crankpin hole that you already suspect is over-tight, I'd be checking that first and easing it off a bit, at least until it is the same as the others.

HTH
Flymo
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Will L
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Re: High Level chassis kit for Class 03/04

Postby Will L » Sun Apr 24, 2011 11:19 pm

John McAleely wrote:Looking at the bind, I've checked the quartering with my gw models jig for each axle, and it seems fine.


Love to know how you did that. I'd have said once the real axle is right through the wheels, the sprung stub axles in the GW jig can't locate in the wheels and therefore the jig can't tell you much about the state of the quartering of a fully assembled wheel set.

I've looked at the crankpins, and with some minor tweaks, satisfied myself they are at 90 degrees to the wheels/axles through their revolutions.

Taking the advice of looking at pairs of axles in turn, I've converted the chassis to an 0-4-0:


That's the way to go

... If I stop the chassis at a free running moment, and then (holding the wheels steady) pull at the rods with my tweezers, I can feel a tiny amount of give. If I let the chassis bind, and then repeat the experiment, at least one of the rods will have no give at all with an attempt at wiggling it with my tweezers. Am I right in thinking that is wrong?


Yup, that's the jam, so you can tell which side it is on and which wheels it is between. It could be the quartering is wrong, but it could also be a difference in the crank pin throw between wheels, crank pins which are not at 90% to the wheel, eccentric crank pin bushes or a difference between the axle centres and the rods. Most likely it's a combination of very small errors in all five. As the rods revolve all the little errors get combine together in different ways. The jam occurs where these add together to the point that the effective distance over the crank pin bushes differs from the distance between the holes in the rods by more than the clearance between the rods and the crank pin bushes.

So the obvious thing to do is increase the size of the holes in the rods and hence the available clearance.

It is in fact very difficult to eradicate all the possible errors, and so you do tend to get binding when the holes in the rods are a perfect sliding fit on the crankpin bushes. The system only works if you provide enough clearance for the cumulative errors, so it isn't cheating to open up the crankpin holes a bit. Just don't do it until your sure that there isn't one big error which is always going to prevent success. When your reasonably sure there are no major errors, ease the crankpin holes in the rods a little bit at a time, with a taper broach or a round file, till the bind disappears. Things should improve as you open up the holes and it should be possible to feel the improvement, it not stop and go look for that major error again. Gold stars to all those whose engineering skills are such that they need very little extra clearance

Finish the job by running it in till its silky smooth.

Second question. The chassis specifies that you need to buy extra 'long' crankpin bushes to the standard kit. This makes sense if each axle needs one. However, that means there is what looks like a lot of sideplay on the two front axles. Is that right? In the pics below, I've mounted one axle as I believe the kit intends, and one with a much shorter bush. Which should I be trying to use? (FWIW the chassis is more likely to bind with these short bushes in use).


You should file down the bushes until they just stand proud of the coupling rods, so the crank pin nut can be screwed down tight onto the bush without gripping the rod. Having them too short or too long can just bring more reasons for the rods to bind.

Will

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John McAleely
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Re: High Level chassis kit for Class 03/04

Postby John McAleely » Mon Apr 25, 2011 11:19 am

Will L wrote:Love to know how you did that. I'd have said once the real axle is right through the wheels, the sprung stub axles in the GW jig can't locate in the wheels and therefore the jig can't tell you much about the state of the quartering of a fully assembled wheel set.


A fair question. I put the crankpins in their slots, and then confirmed that the axle & wheels were all nicely perpendicular and apparently centered over the axle pips.

Anyone got any tips for other methods? To my eye they look at 90 degrees to each other, but judging that by eye while they are on an axle seems unreliable too.

Reading the rest of the post, and Flymo's, I'm feeling more confident to open out the holes on the coupling rods a tad. I've already had to do it a little to get them to sit on the bushes (rather than the ones supplied with the jig), and that did seem to ease the bind a bit as well.

So, I shall file the bushes to size, and then see what a smidgeon of opening up will achieve.

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Andy W
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Re: High Level chassis kit for Class 03/04

Postby Andy W » Mon Apr 25, 2011 11:40 am

"Reading the rest of the post, and Flymo's, I'm feeling more confident to open out the holes on the coupling rods a tad."
Yes, I'd agree with all Will said. That sounds like the way to go re bushes and opening out a tad - just take it steady, and give the reamed holes a delicate turn of an oversized drill on both sides just make sure there's no raised "lip" around the opening.
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Re: High Level chassis kit for Class 03/04

Postby Philip Hall » Mon Apr 25, 2011 11:26 pm

I would also check the crankpin bushes carefully as the occasional one can have the hole a touch off centre. The GW tool should yield a wheelset which is bang on the mark every time, so I shouldn't worry about that. Out of kilter crankpins or bushes are the most likely cause so long as you're sure of the rods/chassis correlation.

Philip

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Mark Tatlow
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Re: High Level chassis kit for Class 03/04

Postby Mark Tatlow » Tue Apr 26, 2011 6:31 pm

A cross checking dodge that I used on the Crab that I got going at Missenden was to use vernia calipers.

Without inserting the jaws very far into the respective holes (so that the back of the jaw does not foul on the other side of the hole), measure the minimum and maximum distances between the various holes.

Start with the axle centres and measure on the left side the leading two axles; measure the inside (the minimum) and the outside dimensions (the maximum) of the axle centres. If you average the two dimensions you will have the exact axle spacing. It should match that to the corresponding two axles on the right side. If it does, you can be confident that these two elements are spot on.

Repeat this for the corresponding holes in the coupling rods; again these should match the axle centres. Then repeat it for the second and third axles – and so on.

I reckoned that I could measure down to about 0.02 – 0.03mm. If the centres of the holes are showing up as a touch different, you can home in on where the error is and thus what needs to be eased and how.

The Comet chassis as supplied has hornways that are to small for the hornblocks, so they have to be eased a bit. I initially did this just to the point that the hornblock would fit but it was still too tight to slide properly. Where I did find that the axle centres did not match the couple rod centres perfectly, I made sure that the final easing of the hornways was to the side that adjusted the axle centres to match those to the coupling rods.

When I first put the rods on the Crab, they were absolutely tight and there was no slack on the crankpin bush at all. The chassis was OK, but not perfect. As Will says there was probably still a couple of errors in it (and of course there was a limit to my ability to check measure it to find them) so a few reams with the broach introduced just enough leeway for the chassis to then run very well.
Mark Tatlow


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