- Joined
- Dec 1, 2010
- Messages
- 1,172
Ok Guys, I think we have all been here before.
I was over at a friends place, and he hasn,t been machining very long. He was not a happy camper that day, and swore his lathe was junk. I thought I would start this topic because we have all been in this bad spot before.
The target of the part is say, 2.750
At 2.780
creeping up on the final size
2.770
2.760
Then your allmost there, should one start sneaking up on the final size .002 at a time, or take the final cut?
I think we all have taken that final cut, and found out 2.750 ended up a 2.748, and damn near had a fit as the part did take some time to make.
Ive found over the yrs, many things can screw you over just when you think your mins from being done, now your starting again.
Here are just a few things Ive seen over the yrs.
1 Made the measurement while the part was still hot.
2 Used a caliper instead of a mic
3 trying to hit the final measurement without leaving any room for expansion of the work piece, and not leaving a few thou extra for the final fitting
4 Trying to hit your final size to a few tenths, and trying to do a fuzz cut or three to get there.
Now these are just a few ways to add another piece to the scrap bin.
Tell us how you get that final size, fit and finish you want.
Hand lap
Hone
Abraisives/ sand paper
tool post grinding
We all have our method to the madness, so lets hear how you do them. This thread could help many newbies from the frustration of trying to get the parts to size, and have it go bad at the end of the job.
I was over at a friends place, and he hasn,t been machining very long. He was not a happy camper that day, and swore his lathe was junk. I thought I would start this topic because we have all been in this bad spot before.
The target of the part is say, 2.750
At 2.780
creeping up on the final size
2.770
2.760
Then your allmost there, should one start sneaking up on the final size .002 at a time, or take the final cut?
I think we all have taken that final cut, and found out 2.750 ended up a 2.748, and damn near had a fit as the part did take some time to make.
Ive found over the yrs, many things can screw you over just when you think your mins from being done, now your starting again.
Here are just a few things Ive seen over the yrs.
1 Made the measurement while the part was still hot.
2 Used a caliper instead of a mic
3 trying to hit the final measurement without leaving any room for expansion of the work piece, and not leaving a few thou extra for the final fitting
4 Trying to hit your final size to a few tenths, and trying to do a fuzz cut or three to get there.
Now these are just a few ways to add another piece to the scrap bin.
Tell us how you get that final size, fit and finish you want.
Hand lap
Hone
Abraisives/ sand paper
tool post grinding
We all have our method to the madness, so lets hear how you do them. This thread could help many newbies from the frustration of trying to get the parts to size, and have it go bad at the end of the job.