I don't entirely understand this command. There are several letter commands that I am not clear on.
I was thinking this command might be the solution.

I'll describe my problem: Mainly it is chip control (more like ball control).
I deep bore (core out) (1.250" to 2.0") plastic rods. The ID's are all over the map so buying rod is not always possible and some of the materials I use just aren't available in tube form.

Bores are usually about 4-5 inches deep.

Materials: Nylon, ULTEM and the like.

Ive been using soluble oil.

If the ID is over 1 inch I usually start using a boring bar after punching it out with the 1 inch drill. I have found if I use larger bits it can get really grabby and causes alot of friction inside.
Or, with the case of the ULTEM material; it gets very chippy and grabby.

The problem is managing the stringy ball of chips.
(Up to this point I have been doing this on a manual lathe, taking delivery of the CNC lathe soon)

My solution has been doing what I would call "peck boring" using my micro mister shooting just air at my R plane to blow the ball of chips off the end of the boring bar on retraction.

I feed in Z about .500 per peck
Retract to the R plane (chip gets blown off)
Incrementally increasing the Z peck depth
Repeating this retracting process till I reach the bottom of the hole.
Open the ID up a little more and repeat.

This works excellent. But as you can see is labor intensive manually.

Will any of the HAAS canned boring cycles solve this problem?

Thanks for any help...

DJ

Originally posted by DEAN
...

I feed in Z about .500 per peck
Retract to the R plane (chip gets blown off)
Incrementally increasing the Z peck depth
Repeating this retracting process till I reach the bottom of the hole.
Open the ID up a little more and repeat.

This works excellent. But as you can see is labor intensive manually.

Will any of the HAAS canned boring cycles solve this problem?

Thanks for any help...

DJ

I use G83 with I, J and K to incrementally decrease the Z's peck depth, I don't think it can be done to increase it.

What CAM are you using? Depending on which one, you could modify the post to create a custom drilling cycle to create a 'long-hand' boring cycle instead of a canned one.

'Rekd

Dean,

I don't know if anything will eliminate this problem on a lathe. I prefer to rough mill (with helical ramp entry) stringy materials when possible, in order to force the production of broken chips.

On most lathes, you can use a G83 pecking cycle as a chip breaker for face boring such as you are doing. It might be an extremely short peck though, because lathe turnings are very long, very fast :)

BTW, if you don't need to feed back out of the bored hole, you might try a straight G83 with a fixed Z peck, or if you do need to do the finish pass, mayhaps creating 2 operations, 1 to rough the chips, (tool flex will likely ensure material left over for the second pass), and one to finish it.

'Rekd teh afterthought

Hu and Rekd, Thanks for the responses.
Gave me a little food for thought. I hadn't considered using the G83 Peck Drilling cycle, seems like a good candidate.

What is L, W, X in these cycles?

Hu, I know you as the BOBCAD guru for the BC forum. I use BOBCAD V18. If I can't get one of these canned cycles to work could I commision you to write me a script to handle it??

DJ

REF:

G83 Normal Peck Drilling Canned Cycle Group 09
F Feed Rate
*I size of first cutting depth
*J amount to reduce cutting depth each pass
*K minimum depth of cut
*L Number of repeats
*P The dwell time at the bottom of the hole
*Q The cut-in value, always incremental
R Position of the R plane
*W Z-axis incremental distance
*X X-axis motion command
*Z Position of bottom of hole

G85 Boring Canned Cycle Group 09
F Feed Rate
*L Number of repeats
R Position of the R plane
*U X-axis incremental distance
*W Z-axis incremental distance
*X X-axis motion command
*Z Position of bottom of hole
* indicates optional

Dean, I suppose I could write a script. The basic principle would probably still follow a G83 peck cycle, although you could add in more pauses and stuff for chip clearing, I suppose.

What kind of drills have you tried using? You might try a spade drill, which gives lots of body clearance, and not nearly so much rubbing land as a twist drill. If it has through the shank coolant, you might be able to take advantage of these passages for getting an air blast right down to the bottom of the hole. This would allow you to drill farther between retractions. I have never tried drilling plastic with a spade drill to see what would happen.

You might also try relieving the edges of a spade drill blade, so that it will cut, instead of rubbing inside the hole. A spade drill may not hog in so badly as a twist drill, if you purchase one without any face rake.

Lots of stuff to try, perhaps someone else has already performed some of these experiments.

DEAN

With all the plastic drillin we have done here has been
chip break drill cycle and even doing that on deep
hole i have had to program the same hole 2 or 3 time
change the stating point on the addition cycles
that way i get clean out and chip breaking bought.

fjd

Can someone explain the letters for this command.
I don't understand: L,U,W, & X

G85 Boring Canned Cycle Group 09
F Feed Rate
*L Number of repeats
R Position of the R plane
*U X-axis incremental distance
*W Z-axis incremental distance
*X X-axis motion command
*Z Position of bottom of hole
* indicates optional


Thanks,

Dean