Any Question Answered

[tapdieuk]

Simpson Springs: Any tips on how not to damage them when fitting wheels, adjusting quarting back to back. I alway seem to damage/bend them despite being careful. Then spend an amount of time to get the contact on the stub axles. 

I the wire available separately, I am running low on springs from n gauge couplers to straightens out. 

[Klaus ojo]

14 hours ago, Donw said:

Not sure what has happened there. When test building a pegged turnout there was no problem. Possibly the pegged chairs hold the rail a fraction higher and the milled crossing is to match that. The only things I can suggest for your turnout is to mark the edges of the crossing onto the timbers/sleepers lift the crossing and then gently file away some of the timber height in the crossing area until the crossing placed on it matches the rail either side, or simply make up a crossing from rail. 

I found I could use  thin ply timbers instead of the plastic ones. I could then araldite thin NS shims to the wood under the crosing and solder the rail onto that. The araldite may softenen when soldering due to the heat but reset on cooling.

 

 

 

Don

Thanks Don,

for your suggestions!   Your timbers are looking really nice! That´s giving me another new variant to try to get a feeling what suits me best. And I´ll  use a soldered crossing for the present turnout with ABS timbers and look if the crossing can be adjusted together with pegged chairs later. I can live with the secrets and mysteries of 2mm modelling remaining in the dark. As long as I get new hints what to tinker with..

cheers

Klaus

Edited January 6, 2022 by Klaus ojo
typo

[2mm Andy]

On 05/01/2022 at 14:35, Klaus ojo said:

Apparently I´ve made a mistake

when trying to build a turnout with the milled common crossing (2mm shop 1-423)  ABS sleepers and nonpegged chairs (1-180 an 1-181) and not using the kit. The cast is about 0.6mm higher than the rail and I even did not use the plastic interleave. Well, I´ll use a soldered crossing now, but where is my mistake and how could I use the milled crossing?

 

Klaus,

 

How thick (high) is the milled crossing? I have just measured a milled crossing I have here (from quite an old point kit) and it is 1.2mm thick.

 

Andy

[Klaus ojo]

Andy,

height of my milled crossing is 1.3 to 1.35 mm. Indeed I missed to recheck this after having removed the crossing.

So I must have raised the timber when fastening the screws. At least for a substancial part of the difference to rail height. Didn´t look like but must have been. Drilling the hole for the screw already caused the timber to distort noticably and I did not dare to drill it larger than 0.95mm.

Now drilled with 1.05mm and filed and scrawked down a bit and it is level. Thank you so much! That did help !  I´ll better care next time!

And again Don,  thanks for the photo of your ply timbers...

yours

Klaus

 

Edited January 7, 2022 by Klaus ojo
final addendum

[Ian Morgan]

I have to say we have given up on EasyTrak point kits after lots of problems with varying gauge (with pinned chairs) and variable depth milled crossings. We have reverted to soldered copperclad.

 

[Jayk]

Have emailed in an order for the 25/0 kit from WW and joined up. So a few more questions, if I may, and I think I'll be good to go.

 

I saw that there are both frame (p/bronze) and drive (bronze) bushes available. Is there any appreciable difference? I was thinking that the phosphor bronze ones were intended for use on the driven axles due to their lower overall thickness and better electrical conductivity. Thankfully I checked and it turns out I had my brain on backwards and that brass is a better conductor. For use in 0.8mm pcb frames the brass ones look a better thickness but am unsure if I'm missing something important.

 

Is there any data available on the rpm values for the association motors? While I'm not wedded to the idea of having a realistic scale top-speed it is something I'd like to design towards. For a scale 90mph running on 7.5mm wheels I calculate that they will need to rotate at ~672.27rpm. With clearances for the gear muffs it looks like I'd need to go with a 21:1 worm/skew-cut driving a 0.3mod14:18 gear train giving a total reduction of 27:1 which would translate to ~18,150 rpm at the motor shaft. It looks like it would be possible to thin a gear muff sufficiently to allow clearance for the 30:1 worm/skew-cut which would increase the total reduction to 36:1 which increases the motor shaft to ~24,200 rpm. I would expect the coreless to be the higher of the two values but don't really have any ballpark for them.

 

Hopefully this will end the interrogation and I can move in to the fun stuff,

 

-Jayk

[Jan W]

I think the frame bushes are bronze because the Mk4 driving wheels had brass stub axles.

Bearings and axles must be of a different material. Drive bushes can be brass because the gear muffs run on steel axles.

I suppose the bronze bushes are not needed with the Mk5 wheels with their steel axles.

 

Jan

[Yorkshire Square]

Motor spec is here:

 

https://tramfabriek.nl/motors.html#motors

[2mm Andy]

The brass drive bushes and phosphor bronze frame bushes are different dimensions (although both have a 1.5mm dia. hole through them) - the brass drive bushes being considerably bigger. I'd use the phosphor bronze frame bushes for all axle holes - that's what most 2FS kits are designed for, although I don't know what the Worsley Works etch makes provision for.

 

Andy

[Jayk]

@Jan W Ah ok, that makes sense. I've never really done anything like this before so hadn't considered that. Thank you.

@Yorkshire Square Thank you, found the coreless one on there but not the flat can. But since coreless seem to be the better performing option that's not really an issue. Rather surprised at the size of the difference between the no load rpm and rated rpm though.

 

@2mm Andy I had thought about about the thinness of the phosphor bronze ones being more suitable for etched side frames particularly as it is a less flexible material, although I don't know how much of a difference that would really make. However the WW is a body only, so I'll be going with PCB side frames which should allow the thicker brass ones to fully cover the drilled hole. Thanks as well.

 

So I guess I'm basically out of excuses now.....

 

-Jayk

[Izzy]

3 hours ago, Jayk said:

Is there any data available on the rpm values for the association motors? While I'm not wedded to the idea of having a realistic scale top-speed it is something I'd like to design towards. For a scale 90mph running on 7.5mm wheels I calculate that they will need to rotate at ~672.27rpm. With clearances for the gear muffs it looks like I'd need to go with a 21:1 worm/skew-cut driving a 0.3mod14:18 gear train giving a total reduction of 27:1 which would translate to ~18,150 rpm at the motor shaft. It looks like it would be possible to thin a gear muff sufficiently to allow clearance for the 30:1 worm/skew-cut which would increase the total reduction to 36:1 which increases the motor shaft to ~24,200 rpm. I would expect the coreless to be the higher of the two values but don't really have any ballpark for them.

 

-Jayk

Most RTR N diesels/dmu/emu motor bogies seem to use around 15-1 total reduction. When I made my class 15 and used belt drive as part of the setup I ended up with 49-1.  With 7mm wheels the top speed is calculated at about 60mph, roughly matching the prototype. But when I made my 2-car 309 EMU I used an old Farish class 20 bogie with just the 15-1 in the mix. Coupled to a 7x16 coreless it runs just as slow as the 15 with both DC/DCC but has a better top speed. Most small motors no-load and load rpm’s can differ widely so aren’t always that useful it would seem. I admire your desire to produce your own motor bogies, I wish I could, so look forward to seeing what you come up with.

 

Bob

[Velocemitch]

A question about motors and mounts for them.

I'm pressing on with my Jinty project mentioned in another thread. This is an old Fencehouses Kit which I started about 15 years ago. It stalled about 15 years ago when I gave up modelling. 

The motor I chose back then was a Faulhaber 816, which was attached via a threaded mount at the very front of the motor. 

Having started to look at the chassis and body more closely I have come to realise the motor is a bit long, it wont fit in the body unless I cut the rear of the bunker off and replace the back with a very thin piece of brass, even then I think the chassis will be about 0.5mm too far forward.

I'm think I ought to swap the motor for one of the smaller 6-15's now available and find a new use for the Faulhaber. But my question is, can I still use this threaded mount, do the association motors have this feature?

Also I do fear I might struggle to remove the worm from the current motor, and wondered if the worms being sold now would mesh with the gear wheel I bought back then. Its a 100DP 30/1 set bevel cut (I think???)

I've attached a couple of photos which hopefully will help.

[Caley Jim]

I'm not familiar with the kit, but it looks to me as though the motor mount could possibly be moved forward a couple of mm, which would solve your problem.  The current worm sets are still 100DP, so current worms will mesh OK.

 

Jim

[Velocemitch]

I might try that Jim, it will likely have to come out if I change to a smaller motor anyway.

its quite close to the gear set as it is, but if I had soldered the mount ring the other side of the spacer I might have got away with it.

I can’t remember why I did it that way, I usually checked these things at the planning stage.

[2mm Andy]

The current Association motors don't have a threaded portion on them, so you could safely dispense with the brass mounting ring if you changed the motor for one of those.

 

Andy

[MrSimon]

I made a cradle for the smaller motor out of plasticard and small bolts and then araldited the motor to it to shape.  

 

I’m two minds about swapping the motor out for a Nigel Lawton one - but when I’ve finished sulking at it and sorted out the quartering and the fixed the rod I bent I might not need ti stronger motor… 

[Velocemitch]

9 hours ago, MrSimon said:

I made a cradle for the smaller motor out of plasticard and small bolts and then araldited the motor to it to shape.  

 

I’m two minds about swapping the motor out for a Nigel Lawton one - but when I’ve finished sulking at it and sorted out the quartering and the fixed the rod I bent I might not need ti stronger motor… 

That's the 6-15 motor isn't it? I think this is the way to go for me as well, I will take the existing threaded mount out and perhaps have a go with one of the association 3d printed ones. It makes no sense cutting the body to fit the Faulhaber one. 

[queensquare]

12 hours ago, MrSimon said:

I made a cradle for the smaller motor out of plasticard and small bolts and then araldited the motor to it to shape.  

 

I’m two minds about swapping the motor out for a Nigel Lawton one - but when I’ve finished sulking at it and sorted out the quartering and the fixed the rod I bent I might not need ti stronger motor… 

 

My original Farish Jinty upgrade, which I did a good decade or more ago, has a 816 motor in it. You do have to thin the rear of the bunker interior down a bit but not a lot. What you can do in yours is get the motor a lot closer to the gears which will give you more room.

As well as a chip mine also sports my usual dodge of a mutilated crew glued to the motor.  So long as the motor is below cab door level the subterfuge is not apparent.

 

With a new chimney, dome, splashers etc it stands up reasonably well against the latest generation Jinty although it could do with a repaint, it predates my ownership of an airbrush and the availability of  proper S&D transfers.

 

Jerry

 

 

[Velocemitch]

Yes thanks, I could take the current mount out, move the motor forward and gain some space that way.

its just I’m probably better keeping the 816 for another project ( I’ve got a broken Mike Raithby 8F which it might suit ) and go for the smaller motor for the Jinty.

it would leave more space for chips, which are a whole new ball game for me!

[Izzy]

Might I say that if you are going to DCC it, (Zimo recommended - plus SA if there’s the space), then the size of the motor isn’t such a concern as the motor control/bemf will ensure it produces enough power I would surmise. Although the NL 8x16 is 5 pole while others are 3 pole I can’t say I’ve noticed any difference in general performance. But they are all CT/Zimo (and SA) fitted.
 

Bob

[Caley Jim]

17 hours ago, MrSimon said:

I might not need ti stronger motor… 

In my experience the strength of the motor is irrelevant.   It's adhesion, or the lack of it, which limits the haulage capacity of a loco.   All of mine start slipping long before there is any sign of the motor being short of power and they all have as much weight crammed into them as possible.

 

Jim

[Hendreladis]

I'd like to fix rakes of wagons together semi permanently which raises a few questions. 

 

Intention is to link, say, ten wagons together with a DG at either end. Presumably certain principles of physics and or geometry apply so I'd appreciate some guidance from those with experience. 

 

The essentials.

 

Wagons are small on a 5'6" wheelbase.

Traditional etched construction.

Dumb buffer at one end.

Ideally rakes will be able to be propelled into sidings as well as drawn forwards by locos.

Minimum radius might be as small as 300mm in extremis but that can be avoided if necessary.

 

Obvious option is simply a loop of wire with a 'hook' to tie the wagons together. No obvious problem in tension but reversing will be a bit rigid. Ideally it'd be good to replicate the slackening of coupling chains and so loop could be elongated.

 

Would that elongated loop invite problems? Presumably the applied force in reverse is more likely to push a small wheelbase wagon sideways and potentially derail?

 

Other option might be to string the wagons like beads on a necklace of fine wire. There are ways to include stops to replicate the tensioning/slackening effect but getting a suitably flexible wire to function properly in forward and reverse will be a challenge. And to anchor the 'bead' at the centre of the wagon or under the buffer beams?

 

Has anybody played with this problem in the past? Are there definitive guidelines on spacings etc?

 

Or will it be better to use traditional, semi permanent 3 link couplings and rely on the buffers themselves?

 

Expectation is two 20 wagon trains comprised of 2 fixed rakes plus brake plus a few peculiarities as required. Stock is all built just awaiting cleaning and final detailing.  Hopefully shop 2 is well stocked for buffers and wheels.

 

Some pics for scale of a selection for scale. Wagons are smaller than, say, a GWR shunter's truck and markedly smaller than a MR horse box. Prototype is simplistically described as "Taff Vale" type and visitors to the NRM have doubtless seen a significantly larger model in the display cases out back.

 

[Caley Jim]

You've been busy @Hendreladis! 

 

I have a few small rafts of wagons (3-5) semi permanently coupled by having a piece of 8thou p/b wire attached behind the headstock of one wagon which comes forward, below the headstock, and then turns up to hook behind the headstock of the next.  Where it hooks under the headstock of it's neighbour you have to make sure that it sits a little below the headstock so as not to lift that wagon and likewise the vertical part does not come right up to the underside of the underframe.  I arrange it to leave 2mm between wagons when pulling and propulsion is done by the buffers, both being the case with my AJ couplings.  So far it has work satisfactorily for me, but my curves are 600mm minimum and that only through turnouts.  You would need to experiment to see what spacing is required for both drawing and propelling through 300mm curves.

 

Jim

[Hendreladis]

8Thanks Jim. Just the person I was hoping would respond. Good to draw on the knowledge of someone with such an esteemed 2mm history.

 

Yup. As I'd thought. I'll experiment. 

 

 Or rather back in the gloat box they go for a while!

[Jayk]

   Ended up having to get the N Gauge class 25/1 as apparently the 2mm 25/0 etching film has gone missing. So I'm currently doing the mental 3D jigsaw of what goes where and how best to go about the order of parts. I've figured out most of it but am stuck on the 6 parts outlined in red below. If they look like anything please jump in!

 

 

   The two center-top I think are bogie mounts but the fold back portion not having a matching hole leaves me unsure. The other four pieces I'm just stumped on, if no other ideas present themselves I'm considering using the two larger panels as blanks behind the bodyside foot / hand holds. The thinner one and the L-shaped one I can't even see where they might be used.

 

-Jayk

Edited May 3, 2022 by Jayk