Two major differences in inside vs outside 1) you can't often see your stopping place, so make allowances like a dead-stop, digital readout, groove, etc. and 2) ID machining requires much more heel clearance on the tool you are using.While I've done external cutting and threading on a lathe, I've never done internal boring or threading. What are the lathe tools best to use for these tasks? I have a 12 X 36 lathe with B size Aloris type toolpost.
ID machining requires much more heel clearance on the tool you are using.
If the heel clearance is insufficient, the tool will rub instead of cut EVEN at the top of the thread. A simpler to see thing about internal machining is tool overhang.Just to make sure I understand that. Depending on the size of the cutting bit, the depth of the thread and the inner diameter of the workpiece, the bit could rub before reaching the bottom of the desired thread?
Mike. who is micro?
"micro 100"..do a google search or your local/online machine tool supplier.
lots of carbide cutters, some solid carbide.
I will usually use the largest boring bar that fits into a hole for both boring and threading. The biggest issue with ID work is getting clearance for the the bar, any clamping hardware on the bar, and not running into the face of the part on blind holes. A slightly above center condition usually stops any insert interference in bores. For small hole threading I use a triangular, 1/4" I.C, (inscribed circle) insert with (3) cutting edges, and a bar that gives ample room to pull out of the cut at proper depth.
When cutting into a shoulder where a relief groove is acceptable, I will sometimes use a left hand threading bar and start the tool in the relief groove and chase the tool out of the part. The lathe is set to run in reverse (clockwise) This produces a right hand thread and takes away the problems associated with crashing the bar and insert into your part. A positive stop on the carriage is used to find the relief groove for the remaining passes.
What does it all mean?
I should have followed instructions.