On 28 Apr 2005 10:27:51 -0700, wrote:


Where were you having trouble with the surface finish? Was it in the
threads?
The trouble was with the urned Dia. Today I had some time to play
with the machine. I changed the
angel a bit, put a slight radius on it, tightened up the gibs,
readjusted the rollers
and prayed for a miricle(as usual) Its quit a bit better although not
nearly as good as I'm used to
with the 12L14. Its also making chips quit a bit different than 12l14.
The 1018 are nearly flat and about 3/16 long and
packing into the toolholder making me have to stop and back the tool
out to get it to cut.
Also the threads were tearing. I tried usinf Tapmagic and that was
fine and then some thread cutting oil
I just got saterday. THe threads were fine with either of these but
with the soluble oil
which we normally use they were as I said torn.
I'm gong to look into getting a thread roller as you suggested.
We are using an older style without inserts.
We had the owner of th shop donw the road and his machinist wander in
and I asked them since they
have a similar machine and do the same parts. Their only suggestion was
radiusing the tool.
And thanks for all the advice. I'm having to learn all this on my own
so thanks
Ken
Ken, I don't know about your setup but for me the extra cost for 12L14
is more than offset by the savings in labor and the quality of the
finish. I see that the chips are packing up. How much time is being
lost clearing chips? If you can, rolling the threads will give you a
much better finish and stronger threads with the added advantage of no
chips to deal with during the threading operation. The drawbacks are
the tighter tolerance to which the threaded portion must be turned to
before threading and the high cost of the thread rolls and the thread
rolling head. If I need to thread parts which are too long compared to
the diameter to get good threads, and of a sufficient quantity, I send
them to J. D. Ott company in Seattle. They require a certain diameter
on the parts and then centerless grind them before threading to
guarantee good threads. Is there any way to grind your tool to
re-direct the chips such that they don't pack up?
Eric