Flymo748 wrote:Will L wrote:Flymo748 wrote:... insulating the sides of a High Level gearbox, to make sure MGthey don't short out on the inside of the body when the suspension is active...
Sorry Paul but I may be being thick here but I'm not understanding the circumstance in which you would need to insulate the sides of you gearbox, and then not have the same problem with metal can on the motor itself?
The slightly sarcastic answer would be that the motor is actually narrower than the gearbox, by a millimetre or two
Now you see how one forgets ones own perversities. I use 10nn flat can motors too, but I always put them with the flats top and bottom to avoid hiding the mounting screw under the worm gear. So, in my mind, the motor is wider than the gear box...isn't it?
In truth, I'd call it a precautionary move more than anything. As this is the first go at a split frame chassis, and one with CSBs as well, then I wanted to be absolutely sure that I didn't have any inadvertent shorting when the motor/gearbox was installed and nestling down between the frames.
I'm sure you'll have experienced one of those intermittent running problems at some point which is an absolute nightmare to diagnose - you know the type: the loco only stops when running through a left hand B6 turnout, in reverse, which three wagons attached but not four or two... So I thought I'd remove one possible factor at the design stage.
Actually that photo also answers my original query as it is quite clear that if your using live frames and CSB then the wires do pass very close to the gearbox sides and so are a potential a source of shorts. And yes those mysterious shorts do happen to us all occasionally. I would be quite interested in how you tackled the insulation on that axle and what is live and what isn't. I haven't been able to find anywhere you've covered it before?
Will L wrote:I recognise the J65 driving wheels though, the balance weights are quite distinctive. Which way does the motor go, back towards the cab or forward into the smoke box?
Towards the smokebox and tilting upwards (not at the angle shown below though, that was just to illustrate the chip fitting location), with the DCC chip and the end of the motor just fitting up into it. The whole thing sits quite low down in the chassis.
I must find time to post some more pictures of the build sequence on my workbench, just to finish the story off...
Well those three are now.