Building a P4 loco chassis fitting the wheels

[hayfield]

I am getting much better at building etched chassis, I still use Romford wheels on my EM gauge locos, despite having some Gibson drivers and a GWR wheel press. Just have not had much luck in quartering wheels

 

I have a couple of small tank locos I want to build in P4, I have noticed in some kits they use the same spacers for both EM and P4. I like to fettle the chassis prior to painting and the thought came into my head that could I do the fettelling using Romford/Markit wheels. Once the chassis is built, tested then painted,  I then can fit a set of Gibsons saving the issue of taking Gibson wheels on and off the chassis

[Brassey]

I think this is the sole purpose of P4 axles for Romford/Markits wheels.  I use them when setting up chassis.  I checked recently and the P4 back-to-back was too big; this combined with deep flanges fouling the chairs. means Romford wheels with P4 axles won't run on my track.

 

They would also be helpful as a quartering aid as a means to check tight spots to eliminate quartering as a problem.  However I am yet to get round to working round how to fit Gibson crank pins to Romford wheels which would be a pfaff.  So far I have not had a major problem with the GW press for quartering.  However, it can put Gibson wheels on too close with too narrow a B2B and they are the devil to get off again.

 

If a kit comes with the same spacers for EM/P4 then I would swap them out for something wider to ensure the wheels are prototypically close to the frames.  I have not gone as far as removing the boss off the back of Gibson wheels yet to achieve this though!

 

Romford wheels on County chassis WIP:

 

 

PS: the other benefit of using the wider P4 spacers is that you can can get a 14xx motor between the frames.

Edited May 6, 2020 by Brassey
Added pic and PS

[sej]

I use the P4 axles to test for good running with Markits wheels before fitting Gibsons/Ultrascale with a GW press...usually works...though not always!

A bit of final tweaking can work wonders.

 

Cheers

Simon

[Siberian Snooper]

When fitting the wheels I use the GW adjustable back to back gauge fitted between the wheels once they are started on the axle. I usually set the gauge slightly over the final back to back, it's easier to squeeze the wheels in a bit more  than pull them out. You may need to take the boss off the back of the wheels so that the wheel rims will touch the b2b gauge.

 

 

[Captain Kernow]

When working in P4, I prefer to do the quartering out of the chassis where possible, so I try to arrange things so that as many of the wheelsets as possible can be dropped out, together with hornblock bearings.

 

This is usually done by attaching the springs to a removable piece of copper clad paxolin, which then screws in place, trapping the wheels and axles in place.

 

[hayfield]

Thank you all for taking the time in replying

 

 I take it that EM Markit wheels work with most P4 chassis spacers then?

 

I cannot seem to get on with Gibson Hornblocks, as per a previous thread I bought a High Level set to try

[PenrithBeacon]

HL hornblocks are brill.

[Brassey]

1 hour ago, hayfield said:

 I take it that EM Markit wheels work with most P4 chassis spacers then?

Yes if using P4 axles rather than EM. I got mine from 247 Developments at a show

[hayfield]

1 minute ago, Brassey said:

Yes if using P4 axles rather than EM. I got mine from 247 Developments at a show

 

Are there P4 axles available then?

[Gordon A]

247 Developments had some P4 axles last year.

 

Gordon A

[hayfield]

1 hour ago, Gordon A said:

247 Developments had some P4 axles last year.

 

Gordon A

 

 

Interesting, I will get on the phone, would be ideal for testing

[hayfield]

I phoned 247 today and ordered 6, he explained that one of his customers asked him to get him son, Marc (Markits) explained he solde very few and had thousands unsold. Turned out to be 200 which solde very quickly and an order for more to be made followed quickly.

 

Just shows what publicity and availability does to sales !!

 

Before anyone tells me they are unsuitable for P4, they are for testing a chassis during the build process and prior to painting, I have some Exactoscale gauge widened track which should compensate for thicker flanges, plus I will use wheels of slightly less diameter to match the P4 Gibson's if diameter is a problem

[PenrithBeacon]

More than one P4 modeller uses P4 track with EM common crossings etc to allow for the use of Markits wheels. I'm thinking of going that way myself, Gibson wheels are a pain in the neck

[hayfield]

Gibson Wheels do look so much better, I must have a proper go at using them

 

As for Markit on P4 axles, nearly EM extra fine 18.8mm with 0.8 flangeways

 

For a 0.6mm difference I would stick with EM, but use P4 on an inglenook 

[Andy Reichert]

2 hours ago, PenrithBeacon said:

More than one P4 modeller uses P4 track with EM common crossings etc to allow for the use of Markits wheels. I'm thinking of going that way myself, Gibson wheels are a pain in the neck

 

I'm confused by this post.

 

(Straight) Common crossings as a separate track component are gauge independent. What matters is the flange width (standard) matching the wheel width (standard) you want to use.  Any P4 wheels running over an EM crossing are going to have a big unsupported vee gap to cross.

 

BTW. What is EM Fine and EM extra fine?

 

Andy

[hayfield]

Andy 

 

If you read my post there is no mention of me using Romfords through a P4 common crossing

 

EM extra fine is one of those derivations of EM, a non educated guess is it was a forerunner of P4, possibly when EM was 18 mm gauge. I do own a scratch built 63xx made years the gauge is neither EM or P4, it has lathe turned Hambling's wheels which are finer than EM but coarser than P4  

[Ref44]

Wasn't there an EEM gauge that predated P4 but was wider than 18.2mm?

[davknigh]

22 minutes ago, Ref44 said:

Wasn't there an EEM gauge that predated P4 but was wider than 18.2mm?

The NMRA had, and may even still have, 00/4mm scale standards that had a track gauge of 19mm but that was for North American outline equipment. EM started at 18mm then moved to 18.2 with some members from the Manchester MRS. 
 

Cheers,

 

David

[Siberian Snooper]

3 hours ago, hayfield said:

Andy 

 

If you read my post there is no mention of me using Romfords through a P4 common crossing

 

EM extra fine is one of those derivations of EM, a non educated guess is it was a forerunner of P4, possibly when EM was 18 mm gauge. I do own a scratch built 63xx made years the gauge is neither EM or P4, it has lathe turned Hambling's wheels which are finer than EM but coarser than P4  

 

I think that the EM extra fine is using P4 wheels and track standards, but to 18.2 gauge. I believe that some EM gauge modellers are using the Exactoscale turnout chairs to build their track.

 

UK railway modelling can be a minefield at times, but each to their own, if it works for you I don't see the problem, so many beaver away in isolation that mixing and matching doesn't matter, unless you want to run your stock on someone else's train set.

 

No I don't want a great big debate on scales gauges and standards in 4mm modelling, it has been done to death so many times already.

 

 

[hayfield]

Why should EM or 00 gauge modellers not use Exactoscale Chairs ?

[davknigh]

1 hour ago, hayfield said:

Why should EM or 00 gauge modellers not use Exactoscale Chairs ?

No earthly reason I can think of.

 

Cheers,

 

David

[Izzy]

I have always thought EEM stood for Eighteen Eight Millimetres. In the distant past I can recall reading about the different track and wheel standards - Manchester etc - at one time being adopted by some modellers seeking finer standards before P4 came along. Which were themselves I believe the result of this ongoing quest.
 

Izzy

[Siberian Snooper]

12 hours ago, hayfield said:

Why should EM or 00 gauge modellers not use Exactoscale Chairs ?

 

10 hours ago, davknigh said:

No earthly reason I can think of.

 

Cheers,

 

David

 

The exactoscale special chairs give the flangeway gap of 0.68mm, whereas the proscribed gap for EM is 1mm. For plain track there's no problem, but EM gauge wheels may well strugle with the 0.68 flangeway gap, especially if the B2B is not spot on. How would RTR wheels cope with that flangeway gap? in 00.

 

 

 

 

 

[Izzy]

You don’t have to use the check rail chairs. I have never used this type of chair. They never existed when plastic chairs first arrived. Just use a mix of ordinary chairs on alternate rails/sleepers and fill the gaps with half chairs when done. This way you can set your own check rail standards at whatever distance you desire. 
 

Izzy

[hayfield]

23 minutes ago, Siberian Snooper said:

 

 

The exactoscale special chairs give the flangeway gap of 0.68mm, whereas the proscribed gap for EM is 1mm. For plain track there's no problem, but EM gauge wheels may well strugle with the 0.68 flangeway gap, especially if the B2B is not spot on. How would RTR wheels cope with that flangeway gap? in 00.

 

 

 

 

 

 

Sorry to be seen to be a bit picky, but that is not the impression you left.

 

To be correct the vast majority of chairs, especially the special chairs (which run into the hundreds) can be used with both EM and 00 gauges without any issues

 

Exactoscale sell 2 types of slide chairs 4CH 302A P4 slide chair & E4CH 301A 4 mm scale slide chair.  The difference is the size of the slide plate

 

The main issue is the check rail chairs 4CH 402A 0.68 flangeway & E4CH 403A 0,8 flangeway, the latter is for P4 gauge widening. However there is a very simple work round for both EM and 00SF which works perfectly and is nearly as good in 00BF. As it happens I have just built an 00BF A5 turnout using these components without any issues at all

 

 

The fact is the whole Exactoscale range was designed to support the Exactoscale P4 company kit range, the vast majority of chairs can be used without any modification on hand built P4, EM and 00 gauge builds, a few of the special chairs do need slight modification even on P4 builds where the hand building method differs from the preformed rail assemblies in the kit.

 

Two versions of slide chair were produced to enable the sale of standard chairs to EM & 00 modellers. I doubt if in the planning stage separate sales of special chairs were thought of, though I guess it soon became obvious there was a sales opportunity selling them as stand alone parts 

 

The main issue arises around the check rail chairs which need to be used in a slightly modified (some find easier to use) form but are still far superior to cutting up standard chairs