I’m finally back to working on my old Rivarossi cab-forward to normal loco conversion (I’m taking styling cues from the SP AC-9 locos). I have the new motor mounted along with the reduction gearboxes and it all works on the test stand. This loco has the good-old large flanges, which makes sense for a $25 used loco! I have tried to find replacment newer drivers for this loco to no avail, so I guess that I am down to modifying the stock drivers to an RP-25 (or close) profile. I know others have done this, so are there any suggestions on the best way to accompli***his? Trying to file down 16 drivers by hand with the mechanism turning seems like a huge pain, especially after I set the thing up to only go a maximum of 75 scale mph! My lathe will not chuck up on something as small as the axle, and I’m not sure if it will chuck up on the drivers themselves either. Any other suggestions would be appreciated, as this is the next step in the building of this loco. Thanks, Morpar
Even if you did get the axle to chuck up, it would probably spin the wheel right off… They are just pressed on… I began the journey you are on with an old Rivarossi Big Boy… I got as far as one of the tender wheels before I got distracted onto something else… The way I did it was to spin the wheel set with a dremel that had one of those rubber sanding drum bits (with out the sanding drum of course) in it… Turn on the dremel, touch it to one side and file the other side… It didn’t take long… Start with a course file and dress it with a fine one when you get close to where you want to be… What I was going to do with the main drivers was make a jig to hold each one in a brass sleeve that would act as bearing… I had a drawing of it but can’t find it… I think you can picture what I’m talking about though…
Jeff
[8D]
I did it the hard way and filed with the drive train running, much smaller engine (0-8-0 as I recall). Obviously that will not work here. Rollieman’s suggestion sounds do able.
Just remember to re-quarter the drive wheels before reassembly. Northwest Short Lines makes a quartering gig for this task.
Good luck and let us know how you made out.
Will
There was an article in MR years ago about doing this. The person reversed the jaws in a Unimat lathe so he could grip on the tire tread and cut a special tool to RP 25 standards so he could machine the flange down. Sounds very complicated but it as quite simple. The key is not to overtorque the jaws and distort the wheel and take your time so you don’t melt the wheel center that is plastic. no need to dismount the wheels from the axle either.