Repeatability/Indexing

[pontiac428]

You can usually be counted on to respond to posts with ignorant, snide remarks when folks have the audacity to do things in a different way than you, and you didn't disappoint with this thread. Enjoy life on Luddite Island.

Just move on when I upset you, okay?

 

[akjeff]

Just move on when I upset you, okay?

Upset, hardly. Annoy is more like it. Will likely just put you on ignore, as I would any other irritating know it all, if I happen upon one in person.

 

[pontiac428]

Upset, hardly. Annoy is more like it. Will likely just put you on ignore, as I would any other irritating know it all, if I happen upon one in person.

It's a public forum. The ignore button will solve your problem. I'm obviously going to keep on doing my thing. So long, mister grumpypants.

 

[mickri]

I am getting more confused after reading the responses to my question. This is my understanding of repeatability. You perform a certain operation. Then remove the tool holder and put another tool holder on to perform another operation. Then you go back to the original tool holder and it is in the exact same position as before.

Another example. My 4 way has 16 indents in the base. I can move the 4 way to use another tool bit. Then go back to the original tool bit. As long as the 4 way sits on the same indent as before the first tool bit is in the exact same position.

If my understanding is incorrect can somebody explain in plain English what the term repeatability means.

 

[Winegrower]

Given the way you've restated your question, yes, it's highly repeatable. I studied that exact situation awhile ago, and the repeatabiiity can't be seen on a 0.001 indicator. I saw an Aloris publication long ago, can't recall where, they claimed the wedge repeats to 50 microinches and the piston to 100. I'm somewhat suspicious, but not going to spend time pursuing this level.

 

[MrWhoopee]

Boys, please! This is not PM.

Even if you're only making one part, repeatability is important. I can't count the number of times I've "finished" a part, removed it from the lathe, tested the fit and found I needed to shave just a little more off. Being able to drop the tool back on and take another .001 without fear is so sweet.

Repeatability is sort of like the opposite of insanity, doing the same thing over and over and expecting the same result.

 

[verbotenwhisky]

Given the way you've restated your question, yes, it's highly repeatable. I studied that exact situation awhile ago, and the repeatabiiity can't be seen on a 0.001 indicator. I saw an Aloris publication long ago, can't recall where, they claimed the wedge repeats to 50 microinches and the piston to 100. I'm somewhat suspicious, but not going to spend time pursuing this level.

I think you can get into diminishing returns pretty quick, repeatability within the ball park is good for me because I run a check each time I switch tools, call me paranoid but I have trust issues....