7mm Steve Beattie 3D-Printed Class 22

[simond]

This photo looks “right”

Can you feed the chain with the gearbox in this position?

Possibly stupid question - can the gearbox go at the other end?

(Which presumably means the bogie about face?)

 

[smgee]

View attachment 236984
This photo looks “right”

Can you feed the chain with the gearbox in this position?

Possibly stupid question - can the gearbox go at the other end?

(Which presumably means the bogie about face?)

Thanks for your input Simon, really appreciated. This is also the direction I'm leaning as it feels "better".

I'll need to make new cutouts for the chain with this orientation:




The gearbox can't go at the other end as it'll intrude into the cab, and the bogie cutout is there for frame clearance I believe.

 

[smgee]

The kit instructions say a Markits or Slater's gearbox can be used with a Delrin drive. No mention of having to modify things to fit.

Maybe narrower Delrin sprockets are available? I bought a Delrin Bo-Bo kit from First Class Kits - two 10-tooth sprockets and a length of chain.

I also don't know if the Markits gearbox is/was narrower than the Roxey one I used, but I do happen to have a new Slater's GB13 gearbox to compare. Bearing in mind that my fettled Roxey gearbox is 12.6mm wide, here's the Slater's product:



Hmmm...

 

[Jordan or Plymouth Mad]

I'd go with option 'B' as well, far better to cut a bit in the middle of the bogie than cut a chunk out at one end.

 

[Ressaldar]

Hi Steve,

for what it's worth, here is a view of my take on the JLTRT Class22 underside which may help. This used a Slater's GB13 gearbox and their Delrin sprockets and chain - like yours, it was a tight fit.



best of luck with your build.

regards

Mike

 

[smgee]

Hi Steve,

for what it's worth, here is a view of my take on the JLTRT Class22 underside which may help. This used a Slater's GB13 gearbox and their Delrin sprockets and chain - like yours, it was a tight fit.

View attachment 237030

best of luck with your build.

regards

Mike

Thanks Mike. I have a JLTRT 52 and that's >2mm wider inside the bogie frames than Steve's kit. With that Slater's GB13, I'd have to lop about 3mm off the Delrin sprocket. Have you pinned yours to the axle?

 

[Ressaldar]

Thanks Mike. I have a JLTRT 52 and that's >2mm wider inside the bogie frames than Steve's kit. With that Slater's GB13, I'd have to lop about 3mm off the Delrin sprocket. Have you pinned yours to the axle?

Hi Steve,

yes I did.

cheers

Mike

 

[Brian Daniels]

This what I did with a JLTRT 22. Can't remember if it's Markits or Roxey, probably Markits. I cut the delrin sprocket down by a couple of MM and I see I did pin them on this model. I have used these loads of times on all my JLTRT models and they all run fine.

 

[Tim Humphreys ex Mudhen]

These drive belts from First Class Kits are great, much easier to use than delrin chain.

A superior range of O Gauge (7mm) Brass Etch Wagon Kits and useful modelling accessories

A superior range of O Gauge (7mm) Brass Etch Wagon Kits. Nearly Everything In The Box Bar The Paint!! First Class Kits also provide useful modelling accessories including Ball Bearings, Transfers, Delrin Products and many more….

www.firstclasskits.co.uk

Tim

 

[smgee]

This what I did with a JLTRT 22. Can't remember if it's Markits or Roxey, probably Markits. I cut the delrin sprocket down by a couple of MM and I see I did pin them on this model. I have used these loads of times on all my JLTRT models and they all run fine.
View attachment 237069

Thanks Brian, that's interesting. I was wary of cutting down the Delrin sprocket too much, but maybe that would have avoided so much fiddling with the gearbox.

These drive belts from First Class Kits are great, much easier to use than delrin chain.

A superior range of O Gauge (7mm) Brass Etch Wagon Kits and useful modelling accessories

A superior range of O Gauge (7mm) Brass Etch Wagon Kits. Nearly Everything In The Box Bar The Paint!! First Class Kits also provide useful modelling accessories including Ball Bearings, Transfers, Delrin Products and many more….

www.firstclasskits.co.uk

Tim

Thanks Tim, I actually bought a drive belt kit from them to try out. Unfortunately the pulley is significantly larger, with negligible scope to cut it down, so I couldn't use it.

 

[Tim Humphreys ex Mudhen]

They do supply an alternative pulley that is much narrower, no boss.

Tim