Flycutter blues....

[Highpower]

Ok, copy that. The chipped bits I was talking about are C5, C6 and were used on interrupted cuts on steel in the lathe. Then again, they are also the cheap Chinese version. :-[

Speaking of cheap junk...
I went to swap out the flycutter for an end mill to start milling the ends of the plates and getting things squared up. I hit the lever on my power drawbar to remove it, and I heard the drawbar rattle loose and spin as usual. But the flycutter didn't pop out of the spindle. Uh oh.....
Hit it again and all it does is spin. So I'm thinking, great - I sheared the drawbar or stripped the threads or???

So I proceeded to tap on the cutter head with a dead blow mallet to see if I could break the taper and get it to drop down a bit. Naturally when it finally popped loose it slipped through my hand and smacked the table below. My first official "idiot" scar on my machine table. :crying:

Didn't find any stripped threads. No broken drawbar. But I took a close look at the tapers on the R8 stub and it looks like the larger taper is a bit bell shaped - slight bulge in the center. Probably very little contact with the spindle taper except at the bulge, so I imagine I was getting some run-out / vibration there. So much for "saving" money buying a cheap tool.

Looks like I'll be spending more money I don't have - again. <sigh>

 

[Highpower]

I've used C-3 and C-5 brazed carbide in fly cutters with little problem. I do tend to lessen the clearance angles as much as possible. Though I find I can't really run them any faster than HSS.

dalee

Hmmmm... that is interesting. I can't say I know a whole lot about using carbide tooling, but it seems to make sense to me that minimal clearance angles would give more support to the cutting edge. Although I have always been led to believe that the higher speeds were always necessary for carbide to perform properly. I don't exactly know WHY that is, but I seem to have read that a LOT. But again, I'm just a self taught HSM guy with not a lot of experience.

I have been pondering whether or not I could clean up the taper on that cutter on my lathe. Trying to think of how I could set it up to hold it securely with the odd shaped head, and still get access to the taper angle with the compound. It never even occurred to me to turn it to a straight shank! DOH!!!

In the meantime, while all this was rattling around in my skull - I went ahead and ordered a couple of straight shank tools (1-3/8 and 2 inch) and another 2-1/2 inch with the R8 taper (again). The difference being that I ordered them from McMaster this time instead of Enco. I've never gotten a Chinese tool from McMaster yet. (knock wood...)

So turning the cheaper tool to a straight shank sounds like an excellent idea dalee. THANK YOU!