andrewdoherty

iTrader: (49)

I have been told that a comm cut with a chipped diamond bit looks just like a comm cut with a perfectly new diamond bit. For reasons I am not willing to divulge I have reason to suspect that my diamond bit may have been chipped. How can one tell?

asw7576

Perfect cut should make the comm shine just like new.

If you don't see shine it means the diamond is chipped.

andrewdoherty

iTrader: (49)

Anthing more obejective? Shine like new seems subjective to me. No offense.

pyrosian

Depending on how the bit is chipped it could possibly cut exactly like a new bit. As long as a piece of diamond is cutting the comm (and not a piece of the surrounding metal) the results will be the same. As long as the cutt is a shiny copper colour and is smooth i would'nt hesitate to continue using the old bit. A REALLY good cut will have an almost mirror like finish.

Korey Harbke

iTrader: (13)

Diamond bits are weird.... I knew mine was done after there were swirl marks on the com after I was done cutting. After careful inspection, I notcied there was a chip on the tip itself. I replaced it with a new one and the finish came back. A good finish with a diamond bit leaves a slight rainbow or CD like finish to it. That lets you know it actually cut the copper and not just smosh it around.

-Korey

Sluggo

iTrader: (12)

A chipped diamond will still cut as long as it has a sharp edge to cut with. If you chip a bit just try to move it in the holder a little to cut with a differant part of the tip and you might get lucky and it will cut. Just how good it cuts is another story. It should cut the metal not push it or roll it over.......If thats the case toss it and get another one.

PlainOleDave

iTrader: (14)

Risky Post but here goes:
I think the ? was how can U tell if the bit is chipped?
If U remove it from the lathe and inspect the bit's tip, U should see a very shiny (possibly triangular) block attatched to the end i\of the bit. It should be shaped to a fine point in one corner. With a magnifying glass, it shoud be real easy to tell if the diamond part is/is not Chipped. Just like if U were to look at an edge of glass that was broken/chipped.
Please don't pound me if I'm off on the actual ?, I is onlt tryin' ta Hep.
POD

andrewdoherty

iTrader: (49)

Thanks guys, thanks POD. I gott find a mag glass aroun d ehre somehwere. I tried to cut a com with the bit and it left the "CD" finish 95 percent of the way across the com. Near the winding tabs, there were some sections that looked rought. The jury is still out. I suppose I will cut a motor and run it next few times I race and see if I notice a dsrop in lap times. We don't race lathes as they say . . .