What would be really useful though would be, for example, having some insulated wagon wheels produced which were to Scaleone32 standards, and then publicising the fact through the newsletter. Peartree could oblige at what is really a very reasonable cost.
I've had a chat to Malcolm Fisher at Peartree Engineering = Model Railway Parts, and now have a better idea of what he can and can't do.
- He uses capstan lathes and form tools, not CNC like Roxey.
- Unlike CNC, there's no particular advantage in trying to piggy-back on a previous customer's orders: the capstan has to be set up mechanically for each batch, regardless of whether a similar batch has been cut before.
- While he'll make a batch as small as you like, he reckons people find a batch of 100 wheelsets (200 wheels) upwards 'economical'.
- If someone orders a batch of Specials, he makes a form tool to their drawing, levies a
nominal charge for it (cheaper than those we've discussed recently) and runs off the batch. He then reserves that tool for that customer. Although an HSS tool has a fairly limited life (even though the lathe drops to a low-speed/high feed for the forming cuts), any order big enough to wear one out brings in enough dosh to fund the making of a replacement without troubling the customer for a second tooling charge.
- His raw material is leaded free-cutting mild steel - better finish but a bit less easy to colour than bog-standard BDMS. He contracts-out hot chemical blackening. Wheels are kept separate to avoid marring in the vat or in drying.
- He's often asked for spoked wheels - often by people unhappy with the stability of injection-moulded wheel centres - but he doesn't offer that service. (Although his website shows some spoked loco wheel castings, they are unlikely to help us.) So his range is pretty well disc wheels, which can be Plain, Drilled, or filled with etched brass representing either brake discs or Mansell 'silent teak', on both sides of each wheel.
- For Insulation, he uses a turned acetal top-hat bush, pressed into the wheel before reaming to suit the axle. Each pair of wheels are pressed on simultaneously, and each wheelset is given a rolling visual wobble check.
Cynric said:
using separate centers and rims means that can have 1000 rims with a choice of 4 different centres rather than having to make say 4000 wheels and have them sitting about for years.
Malcolm can readily produce plain tyres with internal grooves - nice thing about a Capstan
But if the big manufacturers struggle with concentricity , wobble and stability, so might we.
And Simon had valid points with:
Simon C said:
I think that for a "craft" solution the turned tyre with resin/rapid prototyped/moulded centre is the way to go, but I don't really want to spend time "making the wheels" and this approach won't ever "launch" ScaleOne32 in the wider modelling community.
So, in a nutshell, Peartree Engineering is one of our options for insulated steel disc wheels.
. . . Whoever CNC'd the Roxey Mouldings wheels is another such option.
. . . . . . I believe production-engineer Steph had a further option in mind - perhaps with spokes?
David