Compensated Chassis Binding

[Izzy]

 All I would add to Jol's reccomendations if I may is to check the crankpins are true in the wheels. I believe those fitted screw into the Romfords, and keeping them at 90 degrees to the wheel is important. I have found it is all to easy to knock them so they become eccentric.

 

I have often wondered if a quartering jig would be of benefit to me, but can't work out how you make allowance/adjustment for the thickness of the particular crankpins being used so have never made one.

 

Izzy

[Jol Wilkinson]

The quartering jig looks rather like the Cooper-Craft etched one.

 

http://shop.cooper-craft.co.uk/product_info.php?products_id=763

 

The GW version that I have is a wheel assembly and quartering jig (my description), with two aluminium blocks equipped with crankpin locating slots and sprung loaded wheel/axle "locators" and aligned by steel rods.

[Horsetan]

The quartering jig looks rather like the Cooper-Craft etched one.

 

http://shop.cooper-craft.co.uk/product_info.php?products_id=763

 

It started life as a Blacksmith product.

 

There's a similar ex-Bill Bedford variant.

[Izzy]

Good evening Izzy. It doesn't matter how thick or long the crankpins are when using the jig. The jig is a fixed object that when used indicates whether or not each wheelset and their corresponding crankpins are identical to each other. Which they have to be to work efficiently. It doesn't matter either if the jig is set at 88 degrees or 93 degrees ( it would for Romfords though) as long as all cranks are set the same. A couple more items to add however, in the little oil filled bottle are three 1/8" / 25mm. axle setting jigs. These were made for me about 25 years ago by a mate who is a clockmaker. They are extremely accurate and are an invaluable tool as many of the commercially made ones back then had been badly made and could cause binding. It really doesn't take much to throw axles out of line if your not careful!  Also, in the other picture, is the quite dusty GW Models quartering jig. I don't know if it's still available and I've no use for it. Righto. Off for a beer now. Regards. Serron.    

 

 Hi Serron,

 

 Many thanks for the explanation, it was checking the Romfords with it that got me puzzled, how it could be achieved with such a jig when it would set a pair of wheels at less than 90degrees. As you say, doesn't matter when assembling identical sets by hand.

 

regards,

 

Izzy

[Gordon A]

Good afternoon. Horsetan pointed out that the quartering tool pictured was a Blacksmith product and I would not argue with that. He usually knows what he's talking about and I couldn't really remember where it came from to be quite honest. However I did have the GW wheel press and quartering tool, you know, the updated Hamblings wheel press, but I soon disposed of that! Too much slack in the 14 BA crankpin screw slot AND relying on a very fine screw thread to maintain a ninety degree attitude to wheel face whilst only a small amount of the screw thread is actually held by the wheel itself!  This is a big ask for the frail 14BA/ M1 screw to maintain and hold it's position whilst under some pressure. Never mind how careful you may be. This put me right off! It's long gone! Wheels such as U/S and Exacto. need the whole of the crankpin assembly in place before quartering. AGW are a little different and Mr. Pendlenton has covered the provision of much improved crankpins for these wheels extensively in the MRJ. To be quite honest with you I don't bother too much now with steam outline models since "Penbits" came on the scene with those beautifully smooth running sprung power bogies. I do have a backlog of Bradwell chassis to clear and I may get round to them one day but at the moment I am too busy playing with the diesels!  Regards. Serron. 

 

Thankfully Serron a lot of modellers have proved your worries generally unfounded.

Yes it does take a bit of care and finess to quarter steam engine wheels as does etched kit building and yes some people use alternative crank pin systems.

It is just a case of learning a new skill the best way you can. A good reason to join a club / group is to learn new skills and gain hands on instruction.

Also for this subject visit fine scale shows where there are demonstrators who can explain and show you various techniques.

 

Gordon A

Edited September 5, 2017 by Gordon A

[Horsetan]

....Mr. Pendlenton has covered the provision of much improved crankpins for these wheels extensively in the MRJ.....

 

Yes, he went up a size to 12BA.

 

Completely OT, but I think German finescalers use M1.5 for their crankpins - not sure if this is greater or lesser than 12BA.

Edited September 5, 2017 by Horsetan

[ROSSPOP]

I quite agree with you Serron........

 

BUT, following on from my basic  skills   above entry #23

 

5.

Chuck out your wheel quartering jigs.

 

6. spend a pleasant evening polishing your driver axles with very fine emery until those wheels begin to go on the axles by firm finger pressure alone.

( favourite tool.....a cordless drill at the kitchen table )

( particularly effective for those troublesome gibson wheels that wibble and wobble)

 

7. Use a reamer to ensure free bearing movement.

 

8.  Quarter wheels (ON OR OFF) the chassis by eye using the wheel spokes.

 

Bob`s your uncle ....again.....

 

 

 

 

 

Cheers

John   ( P4 modeller.... retired)

Edited September 6, 2017 by ROSSPOP

[ROSSPOP]

Hi Serron

 

Well, if you have mastered the art of a wheel press/quartering jig/tool  then well done you. I was`nt aiming item 5 at you personally,

 

but strongly suggesting a simple working alternative to what should be a simple easy process  for the rest of us.

 

I have only used a Hamblings wheel quartering tool back in the mists of time when `scale wheels` had knurled ended axles that had to be assembled in that way( and you only had one shot at it per axle)

or the wheel centres were b*^$"%d.  I think the early Protofour wheels had tapered axle ends which needed force fitting into the wheels ( and what happened to them)

 

I never got on with the  cumbersome ( to me at least) process of using such a tool in 4mm, particularly when it came to `loading` the  driven axle( before offering up to the jig) with bearings(sprung hornblocks for me), washers, gearbox(with or without attached motor and then reassembling the `drop-out` axles to the chassis..... if ,infact,t it was possible to use drop-out axle units.

 

 

They do not guarantee damage free assembly ( that is accidental removal of wheel substance--plastic/nylon) when using Alan Gibson or Mike Sharman wheels unless you spend time

dressing the axles first. Unless you are very carefull. So why bother in the first place? 

 

Ultrascale wheels are perhaps a different category and I moved away from 4mm before using Exactoscale products.

 

 

Trying to use the tool to P4 a RTR model, of course, is like p!"$*^g into the wind.......

 

 

I would suggest that many loco kit building modellers would find these jigs difficult to use with no guarantee of success.

 

 

As for 7mm chassis building........ Slaters and Walsall Models wheels are like the old Romfords.... self quartering.... Hooray!!!!  ( I wonder why???)

 

 

  AGW wheels are as rare as Hen`s teeth and although far superior in profile would always need a wheel press tool to assemble.  Beyond the skill (me included) of the many.

 

However, I now enjoy the luxury of building 7mm  finescale loco chassis`  with easily removable wheels and gear boxes to aid the painting process.

 

I`ve never made a Finney kit Serron....... too complicated for me !! The chassis in #23 is from a 7mm Dave Andrews Castle kit

 

 

 

Cheers

 

John

[Horsetan]

.....  AGW wheels are as rare as Hen`s teeth and although far superior in profile would always need a wheel press tool to assemble.  Beyond the skill (me included) of the many.....

 

In the context of 7mm scale, do you mean Alan Harris (AGH) wheels?

 

I usually take "AGW" to mean Alan Gibson Workshop for 4mm scale wheels.

[Jol Wilkinson]

I think Mike Sharman' wheels are best left forgotten 

 

Why?

 

Despite their failings, which could be overcome with some care, SW provided the widest range of wheels in 4mm, covering  many prototypes that Ultrascale, Exactoscale, AGW and Romford/Markits have never produced. It is ironic that Ultrascale and Exactoscale produced a number of identical wheel types, while ignoring many others. 

 

The concept of a plastic moulded centre with a push fit axle isn't ideal, especially if you don't know how to fit them well. Tom Mallard's articles on building a couple of LSWR Black Motors in MRJ 165 and 167 showed how SW wheeld could be used to provide very good results.

Edited September 7, 2017 by Jol Wilkinson

[John_Hughes]

I've never been a fan of taking wheels on and off the axles for any reason. Even on a small-scale model the torque transmitted through the rods is quite sufficient to push a wheel which isn't absolutely tight to the axle out of true; but if it is tight to the axle, then removing it and replacing it will to some extent undermine the integrity of the fit.

 

Still, whatever works for you...

[Jol Wilkinson]

I've never been a fan of taking wheels on and off the axles for any reason. Even on a small-scale model the torque transmitted through the rods is quite sufficient to push a wheel which isn't absolutely tight to the axle out of true; but if it is tight to the axle, then removing it and replacing it will to some extent undermine the integrity of the fit.

 

Still, whatever works for you...

John,

 

I agree.

 

However, it sometimes becomes necessary and a looser fit than you usually get with SW and AGW wheels is a help. Ultrascale wheels tend to be a "looser" fit. That then needs a means of positively locking the wheel to prevent rotation on the axle. The benefit of a "looser" fit is that the wheel centre boss doesn't get distorted when the axle is pressed in, therefore reducing wheel wobble and run-out.

 

The late John Hayes used to pin Ultrascale wheels onto the axle by drilling through the boss and into the axle with a .5mm drill and then using Loctite (IIRC) to hold a wire "pin" in place. Another approach is to cut a 45 degree .5mm  slit into the end of the axle - using a fine piercing saw blade - and then drill into the plastic wheel boss to take the wire pin. The wheel can pulled of later if required as the pin will come out of the slit.

 

Frankly, there  isn't a really good 4mm wheel "system" available. The Exactoscale system promised that but is not currently available and covered a very limited range of wheel types. Colin Seymour  (AGW) was looking into self quartering versions of his wheels and Bill Bedford (Mousa Model) has been researching 3D printed centre, self quartering wheels but I believe has found some difficulties with getting the required accuracy for the wheel centre bores.

 

Jol

[Horsetan]

.....there  isn't a really good 4mm wheel "system" available. The Exactoscale system promised that but is not currently available and covered a very limited range of wheel types.....

 

The Exactoscale system isn't particularly helpful if you intend to have working inside motion as the plastic axles are not really designed to allow it in the same way that standard steel axles are.

 

 

.....Bill Bedford (Mousa Model) has been researching 3D printed centre, self quartering wheels but I believe has found some difficulties with getting the required accuracy for the wheel centre bores.

 

He did manage to get some wheelsets (I bought a set for the Bulleid Q1 - the only correct wheels on the market for P4) on sale a few years ago. Very brave, although the material used turned a funny colour if left exposed to light and it was a touch brittle too.... The axles were slotted at 90 degrees (120 was also available for 3-cyl engines such as the LMS Jubilee) so that the "keys" moulded into the wheel hubs would slide into them and be automatically quartered.

 

I have seen Bill's new generation method, which involves resin-moulded centres rather than 3D-print.

Edited September 8, 2017 by Horsetan

[Jol Wilkinson]

 

The Exactoscale system isn't particularly helpful if you intend to have working inside motion as the plastic axles are not really designed to allow it in the same way that standard steel axles are.

 

 

 

He did manage to get some wheelsets (I bought a set for the Bulleid Q1 - the only correct wheels on the market for P4) on sale a few years ago. Very brave, although the material used turned a funny colour if left exposed to light and it was a touch brittle too.... The axles were slotted at 90 degrees (120 was also available for 3-cyl engines such as the LMS Jubilee) so that the "keys" moulded into the wheel hubs would slide into them and be automatically quartered.

 

I have seen Bill's new generation method, which involves resin-moulded centres rather than 3D-print.

He told me he had bought a 3D printer and the samples of some P4 wheels he was producing for a LNWR Jubilee I am building were produced on this. That's where he was having problems with the alignment of the wheel bores.

 

I will have to use a set of Sharman Wheels I have in stock for the Jubilee and hope the BB wheels turn up for the Renown kit I have.

[Horsetan]

He told me he had bought a 3D printer ....

 

Ah, then he must have abandoned the resin idea for now.

[SWTDriver]

I would like to thank everyone who offered help and advice on this problem.

 

After putting the loco back into it's box and clearing my head for a few weeks, I reassessed the whole situation taking on board all that was said here. I then opened up the holes in the connecting rods to a state where they easily dropped onto the crank-pins (and just as easily dropped off I might add). I am pleased to say this did the job, freeing the whole thing up and after several house of minor tweaks it now runs beautifully.

 

I added a Collett tender fitted with the High Level Kits chassis. There are some things that are far from perfect, but this comes of fitting an EM chassis onto a 00 body (hence the overhang of the cylinders).

 

Anyway am am pleased with the results thus far and am numbering it as 6347 which was a Llanelli based engine in memory of a great modeller and friend John Spencer from Llanelli who sadly passed away last month. He was a great encouragement to me as a modeller. 

[leopardml2341]

Really pleased you sorted this. I'm about to start a Comet 4-6-0 chassis and considering whether to compensate it or not. It will be EM btw.

 

What d'y'all think?