"Not" round holes

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KLWestfall
Posts: 93
Joined: Fri Aug 28, 2015 10:17 am
Location: Red Deer, Alberta

"Not" round holes

Postby KLWestfall » Mon Sep 21, 2015 10:02 pm

I have cut a couple of crib boards, and have noticed that the holes are not round. :x

They are drilled with a .125 EM using the drill tool path.

I thought it was because I had re-sized it by dragging a corner handle, (and that may be the problem). I have since redesigned it without any re-sizing, but haven't cut it yet.

All the holes are just "a bit" oblong (not very much, but noticeable) and the all go in the same direction. That's why I thiught the re-sizing was probably the problem.

Anybody have this problem or any ideas?

Thanks for any and all comments...


Keith
Meteor - Aspire 8 (latest version)
Probotix Meteor - :D 8-)
Lots of Wood - 8-)

Funny, I don't remember being absentminded...

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HANNAH024
Posts: 289
Joined: Fri Aug 21, 2015 9:57 am

Re: "Not" round holes

Postby HANNAH024 » Sun Sep 27, 2015 5:45 pm

Keith
I have not had the oblong hole problem with the drilling operation that you described.
Did you use the PECK DRILL operation.
There is always a little bit of deflection with small drills and end mills but peck drilling usually makes it
unnoticeable. If it is a critical hole, I often use the pocket command to form the hole and with the tolerance set to 0.001 they are
round and smooth. For a 0.125 dia hole with a 0.125 dia end mill, I make the hole 0.1255 or 0.126 in dia.
It is what it is!
Have a great day.
HANNAH

KLWestfall
Posts: 93
Joined: Fri Aug 28, 2015 10:17 am
Location: Red Deer, Alberta

Re: "Not" round holes

Postby KLWestfall » Sun Sep 27, 2015 10:03 pm

I believe that I did use the "Peck" drilling mode. thinking that a .125 EM would drill a .125 hole. Some were off by almost a quarter hole and all in the same direction. I've got to try it again on a different file to check.

klw
Probotix Meteor - :D 8-)
Lots of Wood - 8-)

Funny, I don't remember being absentminded...

KLWestfall
Posts: 93
Joined: Fri Aug 28, 2015 10:17 am
Location: Red Deer, Alberta

Re: "Not" round holes

Postby KLWestfall » Sun Sep 27, 2015 10:56 pm

Round or not round.jpg
Round or not round.jpg (3.37 MiB) Viewed 4559 times


I did a 5 inch circle using a .125 EM in Peck Drilling mode.

I did a 4 inch circle using a pocket toolpath.

All holes were .126 dia in Aspire.

While cutting, X & Y did NOT move on screen while drilling holes on either line of circles.

It's kind of hard to see of course due to slight camera angle, but as the holes got towards the top of the circles, they started going a bit oblong. Certainly enough to be noticeable by eye.

Using the EMC@-G64-P005 Arcs (inch) (*.ngc) post processor to set tool paths.

Meteor CNC

Can't seem to post file...:|(
Probotix Meteor - :D 8-)
Lots of Wood - 8-)

Funny, I don't remember being absentminded...

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HANNAH024
Posts: 289
Joined: Fri Aug 21, 2015 9:57 am

Re: "Not" round holes

Postby HANNAH024 » Mon Sep 28, 2015 6:08 am

Keith
You should not notice a 0.005" variation in positioning, but you might try the G64 001 post just to make sure.
Also, does your machine have Brass couplers connecting the motors to the lead screw with set screws
or do you have the compression type shown in the attached picture?
My machine has the older brass couplers and I have to check them often to avoid slippage.

Check the Y couplers to make sure that there is not some slippage there.
PDR_4501.JPG
PDR_4501.JPG (1.14 MiB) Viewed 4556 times
It is what it is!
Have a great day.
HANNAH

popshot1190
Posts: 14
Joined: Wed Sep 30, 2015 9:49 am

Re: "Not" round holes

Postby popshot1190 » Wed Sep 30, 2015 10:33 am

i dont know much ,,,however i have noticed ,mostly because of Light Wave that the software tends to round a digit early,,,like from the 1000th place in stead of the 10,000th place,,,,that doesn't sound like its a factor. Now why i say this is because i can tell light wave where to start rounding and bob cad also has a "show more decimal points feature.". ok now that you know i don't know,,,that's my observation. hahahlolo

KLWestfall
Posts: 93
Joined: Fri Aug 28, 2015 10:17 am
Location: Red Deer, Alberta

Re: "Not" round holes

Postby KLWestfall » Fri Oct 02, 2015 12:39 am

Thanks Hannah,

I believe I have the compression style. I'll check them for tightness tomorrow.

I went back and forth with Len on this for a bit and he suggested that I play with feed/plunge rates, but didn't see any difference. He also suggested that different wood might be a factor, but I get the SAME result no matter what I am cutting in. :(

Not sure what the "G64 001" is - sorry, haven't done any code changes nor really want to... Afraid to make a big mess.

I ran the program again using a 1/8 and 1/4 end mill, and result are the same. Tried cutting a 1/4 inch hole using the 1/8 inch EM - still not round.

Very frustrating. Does using a different post processor make any difference? Is one better that another?

Still appreciating any and all suggestions and help.

klw

IMG_4184.JPG
IMG_4184.JPG (3.54 MiB) Viewed 4535 times
Probotix Meteor - :D 8-)
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Funny, I don't remember being absentminded...

KLWestfall
Posts: 93
Joined: Fri Aug 28, 2015 10:17 am
Location: Red Deer, Alberta

Re: "Not" round holes

Postby KLWestfall » Fri Oct 02, 2015 12:40 am

One other thing. the 4 holes inside the circle, were cut with the .125 EM - no where close to 1/4 :(
Probotix Meteor - :D 8-)
Lots of Wood - 8-)

Funny, I don't remember being absentminded...

hemicro
Posts: 60
Joined: Fri Aug 21, 2015 12:44 pm

Re: "Not" round holes

Postby hemicro » Fri Oct 02, 2015 9:20 am

Have you posted your code and could anyone with the same machine run the code to see if it is the code or the machine?

KLWestfall
Posts: 93
Joined: Fri Aug 28, 2015 10:17 am
Location: Red Deer, Alberta

Re: "Not" round holes

Postby KLWestfall » Fri Oct 02, 2015 11:51 pm

I'll try and post it later. It's on my USB Stick in the shop.

Thanks

klw
Probotix Meteor - :D 8-)
Lots of Wood - 8-)

Funny, I don't remember being absentminded...


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