I am up a creek, and the paddle I brought with me is just too small.
I’ve been repowering my limited fleet of N-scale RSD-15’s using the mechanism from Atlas’s recent Trainmaster, which is a near-perfect match for length and wheelbase. The trouble is that the cast metal frame is too big for the RSD shell, and my attempts to grind it down to size are proving futile. I tried shaving the inside of the shell with a moto-tool, but this is both tedious and inexact, plus I cannot get into the corners with a rotating bit.
So, I am now entertaining the idea of casting new frame halves, except that I have no experience with casting, nor do I posess the equipment. Are there any custom builders or detailers, or even regular manufacturers out there, who would develop and sell such a casting? I would certainly buy about ten pairs for my own use, maybe more depending on pricing. Another thing that could be cast for this project is a new set of truck sideframes (I was just going to leave the FM Trainmaster trucks in place until I figured out a reliable way of gluing on the RSD sideframes).
I wouldn’t give up on modifying the frames you have, making new ones is an involved process, whether cast or milled. There have been many kitbashing articles on locomotives in past issues of MR, RMC, etc. that had to cut and splice a frame to either shorten or lengthen, check the index for back issues so you can get a detailed description on how this was done.
I’ve done frame modifications before, where it involved cutting across the frame to splice it; my trouble is that I need to remove a very small amount of material from the entire side of the frame, i.e. I cannot cut it off, I’ve tried grinding and failed, and I don’t want to get into cutting apart the shell. If it were just for a single unit, I might, but I need to find a workable solution for five or more units.
Since you’re talking about 5 frames, making a jig to hold them would be the first step. I’ll assume the frames you’re talking about are cast metal, such as zamac, and you don’t have access to a milling machine. The jig should be wide enough to hold the frame firmly, and should allow just the amout of the frame to be removed to stick out above it. Oddly enough, the best material for this is wood, like a 2 by 4. The width of the wood, 1.5 inches on each side, will help guide your filing. Use a coarse metal file, lay it across the jig and file off as much metal as sticks above the sides of the jig. If you watch carefully while you’re doing this, as soon as you hit the jig with the file, you’ll see wood dust in the filings. Adjust your file angle to keep from hitting the side of the jig until the frame is just as wide as the jig. Remove the frame, clean up the cut with a fine file, and you’re done.
A grinder, like the Dremel or other brands, runs much too fast and the grinding wheels that come with them will load up quickly with the metal and stop cutting. A coarse metal file will load up, but not as quickly, and can be cleaned easily with a file cleaning card, a wire brush device made just for cleaning files.
If you have any other questions, you can contact me directly at my home email tadiehl@enter.net just use the same subject, so I’ll know what it’s about.
Tom Diehl
I am up a creek, and the paddle I brought with me is just too small.
I’ve been repowering my limited fleet of N-scale RSD-15’s using the mechanism from Atlas’s recent Trainmaster, which is a near-perfect match for length and wheelbase. The trouble is that the cast metal frame is too big for the RSD shell, and my attempts to grind it down to size are proving futile. I tried shaving the inside of the shell with a moto-tool, but this is both tedious and inexact, plus I cannot get into the corners with a rotating bit.
So, I am now entertaining the idea of casting new frame halves, except that I have no experience with casting, nor do I posess the equipment. Are there any custom builders or detailers, or even regular manufacturers out there, who would develop and sell such a casting? I would certainly buy about ten pairs for my own use, maybe more depending on pricing. Another thing that could be cast for this project is a new set of truck sideframes (I was just going to leave the FM Trainmaster trucks in place until I figured out a reliable way of gluing on the RSD sideframes).
I wouldn’t give up on modifying the frames you have, making new ones is an involved process, whether cast or milled. There have been many kitbashing articles on locomotives in past issues of MR, RMC, etc. that had to cut and splice a frame to either shorten or lengthen, check the index for back issues so you can get a detailed description on how this was done.
I’ve done frame modifications before, where it involved cutting across the frame to splice it; my trouble is that I need to remove a very small amount of material from the entire side of the frame, i.e. I cannot cut it off, I’ve tried grinding and failed, and I don’t want to get into cutting apart the shell. If it were just for a single unit, I might, but I need to find a workable solution for five or more units.
Since you’re talking about 5 frames, making a jig to hold them would be the first step. I’ll assume the frames you’re talking about are cast metal, such as zamac, and you don’t have access to a milling machine. The jig should be wide enough to hold the frame firmly, and should allow just the amout of the frame to be removed to stick out above it. Oddly enough, the best material for this is wood, like a 2 by 4. The width of the wood, 1.5 inches on each side, will help guide your filing. Use a coarse metal file, lay it across the jig and file off as much metal as sticks above the sides of the jig. If you watch carefully while you’re doing this, as soon as you hit the jig with the file, you’ll see wood dust in the filings. Adjust your file angle to keep from hitting the side of the jig until the frame is just as wide as the jig. Remove the frame, clean up the cut with a fine file, and you’re done.
A grinder, like the Dremel or other brands, runs much too fast and the grinding wheels that come with them will load up quickly with the metal and stop cutting. A coarse metal file will load up, but not as quickly, and can be cleaned easily with a file cleaning card, a wire brush device made just for cleaning files.
If you have any other questions, you can contact me directly at my home email tadiehl@enter.net just use the same subject, so I’ll know what it’s about.
Tom Diehl