Gearbox for round can motor

[JackD48]

I have an old Mashima 1620 round can motor which I'd like to use in a loco I'm about to start.  I've usually used High Level gearboxes, but I've hit a problem: the boss round the output shaft of the motor is 6mm diameter, whereas the hole in the gearbox that it goes through is only about 5mm for High Level boxes.  I could try opening out the hole, but I'm a bit reluctant to do so as I would probably screw up the precision fit of the parts.  I know that Comet do gearboxes and I've got an old Branchlines one in my bits box, but I can't find any specs or diagrams of what is available.  Wizard sell Comet gearboxes, but no pictures of them, let alone dimensioned drawings. I can't find anything about Branchlines boxes.

Can anyone point me to anywhere where I can find specs for these other gearboxes.  I'm looking for equivalents of the Roadrunner and/or Roadrunner+ boxes, but with a bigger hole.

 

Thanks

 

JackD48

[friscopete]

Pendants and engynneery types please look away .

 

I worked  out in my head, so not a great recommendation ,that if I soldered a motor mount like a piece of  brass channel  to the HL gearbox at 90 degrees to  I could   silicone mount the motor and mesh it perfectly .I always silicone mount on US brass when remotoring , some times making a mounting saddle as well  from black Milliput  and then siliconing on the motor .its a sloppy but great way of getting perfect mesh and still removable by pulling it apart .I didnt use the idea  as I didnt need to .

Edited February 15, 2021 by friscopete

[bike2steam]

No problem opening the 5mm hole if you use a broach which will follow the centre-line unlike a drill that could go off-centre, and you can make the fit as snug as you want.

 

Edited February 15, 2021 by bike2steam

[JackD48]

The gearbox was all assembled and it was only when I came to screw the motor on that I discovered the problem - hence I'm reluctant to mess about with it. I've used an alternative motor so I'm not desperate for a solution.  I'll have to order up a gearbox for the next project, hence asking about alternatives, but I expect that opening up the hole with a broach whilst still on the fret (just like opening up the bearing holes) would be much safer.

Thanks

JackD48

[ianLMS]

I have just fitted an old round Mashima motor to a Comet 2-stage gearbox. Everything lined up nicely. It was an old gearbox though so was possibly made around the same time the round motors were available.