I have been experimenting with some brass and the Burr-Beaver seems to work pretty good depending on how one feeds it. I have my large pulley for my Nichols in the shop being welded, so that I can leave that one on the machine all the time. I'll have 2 more speeds to try with the double angle cutters. The Bur-Beaver works pretty darn good though, just seems a bit finicky to understand. I suspect bronze will be a bit harder to chamfer on it. Here's a link to the tool:
Just out of curiosity, have you ever used a router to chamfer the spines? If so, how does the finish compare to the Bur-Beaver? Regards, Isaac
Isaac, No, I haven't tried it but JoeF mentioned to me that whoever makes your backs does it that way. I was able to get close enough with this machine that I think I could finish up the minor touch-up with a file...but the idea is to get as clean as possible. I still need to try my horizontal mill when I get the step pulley back from the welding shop. I think I would like to get the chamfers the same size as the flat on top, and only chamfer the nose and top. The backs I am slotting are good enough for a kit, IMO. I'm still ironing out my split-nuts. I think I will be producing my own split-nuts to provide with my own kits also. I could match Wenzloff & Sons on slotted back pricing, but want to provide a better value with more detail if possible. I would like to provide the back/plate as one unit. That way the person building a kit would only need to worry about assembly and the handle.
He does chamfer them with a router. He just made a 45 degree bit out of HSS, and the finish is good enough that it just requires a little sanding. I think the key is making sure the brass is held very tight to the fence. Isaac
If that is the case and they also need to be lightly sanded, this Bur-Beaver will do that for me. This is pretty safe, as the cutter is only on the chamfer underneath, and this is really quick to run through the machine. I was hoping to get an absolute perfect chamfer and think I might be able to do that on the horizontal mill, given more speed. I have my 5-step pulley in the shop being repaired so I can try the 2 higher speeds, I'm currently using a 3-step pulley. The one area I need to devise a fixture is for doing the nose, I'm currently using a small Starrett 4" square for the nose, and would like to make something more secure to hold it while it moves the nose end over the cutter.
Do you just push the brass through the Bur-Beaver by hand? Do you need a fence or holddowns? And do you climb cut with it? It looks like a good idea for putting the chamfers on. My machinist tried doing it on the mill, but said it was very difficult. I think he was having problems with rigidity, and every little variation is very visible on a small chamfer like this. Isaac
Yes, I push it through by hand. I would like to make a small fence that will ride on the top of the plate, to hold the back at a 90 degree to chamfer the nose, but I can get a pretty good one by doing it with a small Starrett, and holding it. The Bur-Beaver is quite an expensive unit, about $1500, but I bought a used for about $325 and got a new cutter for it ($90). I have about $425 into it. This works quite well, but I need to try this with higher speed (i.e., mentioned waiting for the 5-step pulley to come back from the welder). What I might be able to do is have those 2 angle cutters together and a screw slotting saw so that I could slot and chamfer by just moving the table. I can slot a 20" back with this setup. And on the Bur-Beaver it's easy to push it through, so that might be best time wise.