RT Models J94 chassis questions.

[highpeakman]

I have a DJ models J94 which suffers from the dreaded jerking when running downhill on my rendition of "Hopton incline".

 

I am currently considering whether to build the RT chassis and mounting the DJ body on it. I have purchased other RT items and have been very happy with them. This question is not at all about the quality of the RT product but about the suitability for someone who is inexperienced like me to assemble. I have never built a model chassis before so hope to use it as a first step and learning process in such matters. I am a reasonably experienced modeller but not in metalwork  although I do have some practical experience of soldering. I have searched around on RM Web but cannot find any comments about this chassis but it would be helpful if someone could comment whether this is a good route to use for a beginner in chassis assembly.

 

If someone could suggest a suitable motor/gearbox combination that would be most helpful as would a suggestion for the best wheels to use. A new venture for me so any help would be appreciated. Thank you.

[PMP]

I’ve got two of their chassis’ to do. I’ve not started either yet, however I do have experience of chassis building.

The kit looks well designed, simple and straightforward to assemble. RT have a good reputation for ‘build ability’ and quality from their other kits, so looking at the physical product it’s probably as good a place to start for a beginner as anywhere. I’ve not yet determined the drive train choice for my two but my first port of call will be the https://www.highlevelkits.co.uk range. Within that, there will be an appropriate drive system. I’ll be driving from the rear axle configuring it as a rigid chassis. Wheels are available from http://www.alangibsonworkshop.com/4mm.html these will be my choice, Markits may also have them in their range. 

[mike morley]

I've got one built with a second to be done.

An RT Austerity chassis is well within the capabilities of a novice. The only area you might find tricky is the buffer beam gussets, where holding them in position while soldering them in place without scorching your fingertips in the process can be . . . interesting.  At one point I managed to solder a pair of tweezers to the chassis!  For that reason I'd advise building the single-gusset version (not sure if the J94s had double-gussets, anyway).  Apart from that, its all very straightforward.

Confidence is everything, so I'd suggest a bit of practice on odd scraps of metal to get into the swing of things before starting the actual chassis.

Mine has a big 1628 Mashima and a High Level Road-Runner Plus powering it.  That vast saddle tank is more than capable of accommodating pretty much any motor intended for 4mm use so I'd suggest asking Chris at High Level what he recommends when you order the gearbox.

 

Edited to add that Markits do indeed do appropriate wheels.  The one I've built has got Markits wheels, the one waiting to be built will have Gibson wheels.  Markits wheels are more expensive but much, much more novice-friendly.

Edited October 16, 2021 by mike morley

[PMP]

@mike morleyGot any pictures of your build? Including body on/off please 

Edited October 16, 2021 by PMP

[mike morley]

Full bells and whistles upgrade of a Hornby body.

 

I'll dig her out and take a picture of her undressed later.

[mike morley]

 

 

 

I have a Markits Wakefield lubricator I wanted to use and I thought the best way to install it without making things excessively complicated would be to make a replacement nickel-silver footplate that was part of the chassis, rather than the body.  In the end, I didnt fit the lubricator (chickened out) but I might go back to it another day.

 

I find with saddle tanks in general it is easier to make the tank and boiler a separate unit that slides over the motor from in front like a sleeve.  I've got three saddletanks built and two being built that way so I've done it often enough to know it works.  Far easier than the weird and wonderful contrived system Hornby (and, I think, DJM) used for making the bodies detachable on their Austerities/J94s.

Edited October 16, 2021 by mike morley

[doilum]

Just for the record: double gussets standard from HE 3700 of 1950.

Others were retrofitted later. Even in 7mm they are a pain due to the non prototypical working buffers.

[highpeakman]

1 hour ago, mike morley said:

I've got one built with a second to be done.

An RT Austerity chassis is well within the capabilities of a novice. The only area you might find tricky is the buffer beam gussets, where holding them in position while soldering them in place without scorching your fingertips in the process can be . . . interesting.  At one point I managed to solder a pair of tweezers to the chassis!  For that reason I'd advise building the single-gusset version (not sure if the J94s had double-gussets, anyway).  Apart from that, its all very straightforward.

Confidence is everything, so I'd suggest a bit of practice on odd scraps of metal to get into the swing of things before starting the actual chassis.

Mine has a big 1628 Mashima and a High Level Road-Runner Plus powering it.  That vast saddle tank is more than capable of accommodating pretty much any motor intended for 4mm use so I'd suggest asking Chris at High Level what he recommends when you order the gearbox.

 

Edited to add that Markits do indeed do appropriate wheels.  The one I've built has got Markits wheels, the one waiting to be built will have Gibson wheels.  Markits wheels are more expensive but much, much more novice-friendly.

 

Mike

Thank you very much indeed for your comments, pictures and guidance. Very helpful. 

I just need to take a deep breath and then plunge in with orders! 

Thanks.

Don

 

[highpeakman]

2 hours ago, PMP said:

I’ve got two of their chassis’ to do. I’ve not started either yet, however I do have experience of chassis building.

The kit looks well designed, simple and straightforward to assemble. RT have a good reputation for ‘build ability’ and quality from their other kits, so looking at the physical product it’s probably as good a place to start for a beginner as anywhere. I’ve not yet determined the drive train choice for my two but my first port of call will be the https://www.highlevelkits.co.uk range. Within that, there will be an appropriate drive system. I’ll be driving from the rear axle configuring it as a rigid chassis. Wheels are available from http://www.alangibsonworkshop.com/4mm.html these will be my choice, Markits may also have them in their range. 

Thanks for your comments. All valuable information and guidance. Appreciated.

 

[pete_mcfarlane]

2 hours ago, mike morley said:

I've got one built with a second to be done.

An RT Austerity chassis is well within the capabilities of a novice. The only area you might find tricky is the buffer beam gussets, where holding them in position while soldering them in place without scorching your fingertips in the process can be . . . interesting.  At one point I managed to solder a pair of tweezers to the chassis!

Ceramic tipped tweezers are the way forward. You'll never solder the tips to anything again.

[PMP]

Looking at @mike morley’s model that’s a Dapol/Hornby version. I suspect the DJM body fitting to chassis  won’t be as straight forward.

[Captain Kernow]

On 16/10/2021 at 13:02, PMP said:

I suspect the DJM body fitting to chassis  won’t be as straight forward.

This was also my concern.

 

I have an unpowered pre-production version purchased from Kernow MRC at one of the Taunton RMWeb Members Days a few years ago. I am planning on building a chassis for the body of this loco in P4, but if it's anything like the awful arrangements in the Hattons/DJM 14XX, then it's not going to be straightforward.

 

[cypherman]

Hi all,

I don't know if this may be an easier option. But could you not use a cheap second hand Dapol J94 chassis instead.

[Colin_McLeod]

18 minutes ago, cypherman said:

Hi all,

I don't know if this may be an easier option. But could you not use a cheap second hand Dapol J94 chassis instead.

 

Or claim on the warranty. 

 

Oh wait ....... 

[highpeakman]

24 minutes ago, cypherman said:

Hi all,

I don't know if this may be an easier option. But could you not use a cheap second hand Dapol J94 chassis instead.

Thanks for your comment. That's an interesting question and I have wondered about it. Does anyone know if the DJ body can be fitted easily to the Hornby chassis?

 

However, while I would like to know the answer, the reason for the original post is that I would like to have a go at chassis building so I thought that using an RT chassis would be a way to learn and provide a solution to the DJ problem at the same time.