I would look for another can motor.
Simon
T.C.I would use the Dremel with a corse drum sander. Cutters will want to jump all over the place, the sander will give you a smother finish. T.C.
Thank you for your advice as well, T.C. My tool isn't Dremel brand, but I think I have some of the corse drum sander bits. I'll have to look into it.
Thank you, Mel and Wayne, for your advice. This is the rotary tool I have: https://www.walmart.com/ip/Hyper-Tough-1-5-Amp-Rotary-Tool-with-105-Piece-Accessory-Kit-AQ25018A/477158316 I don't have anything like the Dremel #115 bits unfortunately, but I do have some files similar to what Wayne suggested. I'll have to give it a try and see if they'll fit in there. If not, I'll have to figure something else out. My rotary tool has some grinding stone bits, (I think there's a photo of them in the link I provided. They're a red-orange color). Would any of those work?
I'm not sure if there's enough room in that locomotive for it to work, but another option might be an autobody file....
I use them all the time for thinning stock plastic running boards, and they remove the material quite rapidly. I tried one, a minute ago, on a cast zinc steam locomotive frame, and it removes that material pretty rapidly, too, although not as quickly as it does plastic.
I also checked my John English "Yardbird", to see the location of the material you need to remove. Mine's retired - it never was a good runner, but it makes an interesting scenic feature as it awaits scrapping...
Wayne
Hi everyone. I am attempting to restore a John English/Hobbyline PRR A5 0-4-0 that I got from a friend for a couple of dollars. Here's a diagram: https://www.hoseeker.net/hobbyline/hobbyline2000Kyardbird040pg2.jpg I'm at the point where I need to install the motor. I have a Pittman motor (it's the smallest I could find that has a long enough driveshaft) that will fit in the shell with the exception of a 1/4 inch long area in front of the firebox that narrows down to about 1/2 inch wide. In order for the motor brushes to clear the shell wall and not short out on it, I need to widen it by 1/8 inch. So, I need to take off about 1/16 of an inch on each side, I think. I believe the shell is made of zinc, by the way. I have a rotary tool that I'm pretty sure will work, but I'm not sure what type of grinding head/bit to use. Specifically, what shape. Any suggestions or tips would be greatly appreciated.