- Joined
- Dec 3, 2017
- Messages
- 2,156
Hello all,
So here’s my issue: I must be doing something wrong because I can’t get any die to start. My dies are not expensive,but they are new. I had thought to blame the dies. Some of them won’t even thread onto a store bought screw. So today I was looking to thread a (unknown metal) shaft m8x1.25. Turned it to .315”, and fought it till the end of the rod was chewed up. Turned it it .307, and tried again. Same thing. Turned it to .302, and tried again. No go. So it’s technically too small I think, at this point. Anyhow, my final idea was to turn a 5 degree taper on the end of the shaft, to try that. Ofc, at this point the parts at .302, and hanging out of the chuck 2 inches. Turning at 220 rpm, the cutting tool grabbed the part and bent it. I’ve got three hours in this part. So I laughed at myself. Having “known better” and then having the machine prove it to me, I can do nothing but laugh at myself, and start over. The (12l14) part gets remade, this time with a taper on purpose over about a quarter inch. Anyhow the die (or my tactics) still doesn’t work. I have the idea to start the thread with an old adjustable 5/16-18 die I have. The size being very close. This works! After two threads , I switch to the metric die and it’s easy as pie. So I did get it done, but this is the only size I’m aware of that would actually work like that with. Long story I know. But the devil is usually in the details. So what’s the problem? After I had a couple threads, the metric die worked great. Are my inexpensive dies just absolute junk? Or is there a possibility that I’m doing something wrong? I tried to use the tailstock to put pressure on the die to help it start. Put my success came when I took the part out, put it in a vise vertically, and used the big antique standard die. I will say the old dies I have, start with almost no effort, but cut oversize. The new dies seem under size, and won’t start....like never. I can’t say I’ve had success with any of them. Usually I’d just single point the threads, to avoid using the dies. But this being a metric thread I was unable. I guess I could have single pointed 18tpi, for three threads, but I’m skeptical I’d have succeeded at that either. So again, bless you if you read this whole thing. Suggestions? Advice? Questions? What do ya got? Thanks in advance!
So here’s my issue: I must be doing something wrong because I can’t get any die to start. My dies are not expensive,but they are new. I had thought to blame the dies. Some of them won’t even thread onto a store bought screw. So today I was looking to thread a (unknown metal) shaft m8x1.25. Turned it to .315”, and fought it till the end of the rod was chewed up. Turned it it .307, and tried again. Same thing. Turned it to .302, and tried again. No go. So it’s technically too small I think, at this point. Anyhow, my final idea was to turn a 5 degree taper on the end of the shaft, to try that. Ofc, at this point the parts at .302, and hanging out of the chuck 2 inches. Turning at 220 rpm, the cutting tool grabbed the part and bent it. I’ve got three hours in this part. So I laughed at myself. Having “known better” and then having the machine prove it to me, I can do nothing but laugh at myself, and start over. The (12l14) part gets remade, this time with a taper on purpose over about a quarter inch. Anyhow the die (or my tactics) still doesn’t work. I have the idea to start the thread with an old adjustable 5/16-18 die I have. The size being very close. This works! After two threads , I switch to the metric die and it’s easy as pie. So I did get it done, but this is the only size I’m aware of that would actually work like that with. Long story I know. But the devil is usually in the details. So what’s the problem? After I had a couple threads, the metric die worked great. Are my inexpensive dies just absolute junk? Or is there a possibility that I’m doing something wrong? I tried to use the tailstock to put pressure on the die to help it start. Put my success came when I took the part out, put it in a vise vertically, and used the big antique standard die. I will say the old dies I have, start with almost no effort, but cut oversize. The new dies seem under size, and won’t start....like never. I can’t say I’ve had success with any of them. Usually I’d just single point the threads, to avoid using the dies. But this being a metric thread I was unable. I guess I could have single pointed 18tpi, for three threads, but I’m skeptical I’d have succeeded at that either. So again, bless you if you read this whole thing. Suggestions? Advice? Questions? What do ya got? Thanks in advance!
