valensdiesel
Plastic
- Joined
- Apr 3, 2020
Hey all,
Hopefully you can give me a bit of advice on how to tackle this particular problem. I've got to place 24 tapered holes around the circumfrence of a circular object, (a wheel for a rotary punch). The taper is designed as a JT1 to accommodate some insertable punch tools which I will also have to make. This will be a one-off setup, but if you've read this far, you've probably already realized the tolerances involved are...fun. I think I've got a pretty good handle on the location issues (serendipity is a wonderful thing), so my question at this point is, how would you make the holes themselves?
I am fortunate enough that I own a Tree tapered boring head, so my plan is currently to drill then straight bore with a tenthset to the small diameter of the taper, then come back in with the tree boring head and cut the taper in a single pass. The "socket" is actually shorter than a standard JT1, so the difference in large to small diameter is only 0.018", but the snag is this is going through either 17-4 PH or Custom 465, if I can get it in an appropriate size.
I found a vendor in PA that makes JT taper reamers in M2 HSS, and I know some others here have had good results with his tools. Given that I can get a JT1 reamer, would you follow the tree taper bore with the reamer to clean it up, or do you think I should make a lap and clean the bores that way, or do you think I can get away with a single-shot with the tree head and still have good location and retention with the punch tools? The tree boring head typically makes very nice holes, but the material gives me pause, as the tree head's feed is fixed at 0.005" per rev and I think those grades of stainless are run with less feed. Also, recommended material for custom 465 is carbide (so possibly also an issue with that HSS reamer), which tends to like heavier feeds than it's going to get at the end of the hole, so I'm worried about the effect of rubbing at the bottom of the taper.
I'd appreciate any advice y'all can offer. You guys are a wealth of information and experience.
Thanks in advance!
Hopefully you can give me a bit of advice on how to tackle this particular problem. I've got to place 24 tapered holes around the circumfrence of a circular object, (a wheel for a rotary punch). The taper is designed as a JT1 to accommodate some insertable punch tools which I will also have to make. This will be a one-off setup, but if you've read this far, you've probably already realized the tolerances involved are...fun. I think I've got a pretty good handle on the location issues (serendipity is a wonderful thing), so my question at this point is, how would you make the holes themselves?
I am fortunate enough that I own a Tree tapered boring head, so my plan is currently to drill then straight bore with a tenthset to the small diameter of the taper, then come back in with the tree boring head and cut the taper in a single pass. The "socket" is actually shorter than a standard JT1, so the difference in large to small diameter is only 0.018", but the snag is this is going through either 17-4 PH or Custom 465, if I can get it in an appropriate size.
I found a vendor in PA that makes JT taper reamers in M2 HSS, and I know some others here have had good results with his tools. Given that I can get a JT1 reamer, would you follow the tree taper bore with the reamer to clean it up, or do you think I should make a lap and clean the bores that way, or do you think I can get away with a single-shot with the tree head and still have good location and retention with the punch tools? The tree boring head typically makes very nice holes, but the material gives me pause, as the tree head's feed is fixed at 0.005" per rev and I think those grades of stainless are run with less feed. Also, recommended material for custom 465 is carbide (so possibly also an issue with that HSS reamer), which tends to like heavier feeds than it's going to get at the end of the hole, so I'm worried about the effect of rubbing at the bottom of the taper.
I'd appreciate any advice y'all can offer. You guys are a wealth of information and experience.
Thanks in advance!