Making a Plymouth Sound!

Accucraft in the USA made this nice brass model of a Plymouth switcher in both 0n30 and 0n3 gauges.

AM5501-C-L-600

Catalogue Image of the loco

For a loco that cost as much as this one did its let down by some really crap engineering in its drive and chassis with very noisy gears and bearings that are prone to going round in the plastic instead of the the shaft revolving in the bearings.

If you could get it to run smoothly they were always very noisy which made a DCC and sound installation a bit problematic for which the wiring was rubbish anyway.

Motor-600

0n3 & 0-14 versions of the power truck

Over the years since it was first introduced I have fettled up a few of them and have got to the point where I won’t do them for customers as the time you have to put into it far outweighs the value and generally just results in a lot of bad language.  I’ve got to the point where I have two or three here which have either had their chassis cannibalised to get others running or that I just can’t face sorting out. Now a plan has been hatched –  a new chassis and 0-14, 0n3, and 0-16.5 versions.

Chassis_base-600

Chassis with the temp card adaptor

First thing was to ship a loco to Geoff Baxter at Hollywood Foundry in Australia for him to have a look at making a new chassis for it using a custom version of his BullAnt mechanism.

What came back was this super little job and now there are 0-14 and 0n3 versions here. The chassis has worm drive to each axle, belt drive from the motor, a decent motor and flywheel. Even without the weight of the body on them they run really smoothly.

Adaptor1-600

Top Quality! Card adaptor plate

As they arrive they don’t immediately fit in the loco and some adaption is needed. Firstly, a few no longer needed bits get cut off with a slitting disk and the edges cleaned up. This allows the chassis to drop in but also allows it to drop right through! An adaptor plate is needed.

The Mk1 adaptor plate to test dimensions was done in good old fashioned card. This got some of the sizes right but it doesn’t replicate either the thickness needed to get the ride height right or any means of fixing it to the loco or the chassis to it.

AdaptorPlate600

Screen Capture of 3D part

So out with the 3D CAD. Sometime later this drawing existed and has now gone off to be 3D printed. Just one for now as there will undoubtedly be some slight mods required.

As usual with a project for me instead of a customer this may well blow hot and cold and take ages to go any futher but the target is a DCC sound fitted loco with keep alive installed and, above all else, decent slow running.

More news as it happens – don’t hold your breath!