Bachmann 3F tank and Brassmasters rods

[Hardwicke]

I'm having difficulty with the Brassmasters rods on the Bachmann 3F tank. It is not possible to set it up in the traditional Sharman way of checking one rod against the other from the initial driven axle. Additionally the set up of of the rods with the rivetted knuckle leads to a slight variation on length. Added to this, the sprung middle axle leads to a binding of the axles as it pushes on the chassis base and results in a non free running chassis ( I'm using 1/8th axles of Gibson origin as opposed to the 3mm ). I've opened the axle slots out slightly with a reamer. Would removing the spring or cutting it further solve this?

[Philip Hall]

In any chassis with slots for bearings I would always set up a set of jig axles and check whether the slots actually match the rods. Even the rods that come with the chassis may not match, so in taking up some of the excessive slop we can have problems. Possibly when you opened up the slots for a 1/8" axle it made a difference to the alignment, maybe even more so if new rods were constructed. So I would drop some jig axles in the slots and compare and adjust.

Philip

[Alan Turner]

See here: viewtopic.php?f=105&t=913&start=175

regards

Alan

[grovenor-2685]

Not that it helps much but I used AG conversion sets with 3mm axles and Bill Bedford rods and all fitted.
In use the centre axle should be held up off the keeper plate by the wheels sitting on the rails, otherwise the wheelset would not be pushed into a depression by the spring. The larger axles could affect this, if the centre axle cannot drop below the end axles then the keeper plate needs relieving a bit.
Regards