Help-Pocket with larger clearance tool

This forum is for general discussion about Aspire

Help-Pocket with larger clearance tool

Postby MoHawk » Wed Feb 06, 2019 6:16 pm

Recently I've cut 2 clocks using 1/16" end mill for detail and 1/4" end mill for milling larger clearance using 0.125" depth. I used the "Auto Tool Zero" function in Mach3 in the same spot for both tools. On each clock, the 1/16" end mill cut slightly deeper than the 1/4" clearance. It's enough deeper that there is a visible outline around each item in the clock. Since the depth of cut stays constant on both cutters with any change, is there a way to correct for this problem?
Attachments
Geese-Clock.JPG
Geese-Clock Detail 2.JPG
MoHawk
 
Posts: 7
Joined: Tue Jan 11, 2011 4:41 pm
Location: Mid Missouri
Model of CNC Machine: CNC Router Parts Pro 4824

Re: Help-Pocket with larger clearance tool

Postby dealguy11 » Wed Feb 06, 2019 7:47 pm

The problem is going to be 1) wood movement 2) bit moving in the collet, or 3) your zeroing routine is not as precise as it needs to be. As you cut wood away, it does move. Figuring out a good hold-down technique so it doesn't move in Z is important in this kind of cut. Not sure how your auto zero routine works - do you have a touch plate? Are you using the paper method? Whatever it is, work through carefully to confirm you're really getting the tool heights measured properly.
Steve Godding
D&S Artistic Woodworking http://www.dsartisticwood.com
User avatar
dealguy11
Vectric Wizard
 
Posts: 1445
Joined: Tue Sep 22, 2009 9:52 pm
Location: Henryville, PA
Model of CNC Machine: Anderson Selexx 510

Re: Help-Pocket with larger clearance tool

Postby MoHawk » Wed Feb 06, 2019 11:20 pm

The 1" thick circle is very flat and was held down with 6 Rockler clamps. The first, clearance pass was with 1/4" down cut end mill and is dead on 0.125" in depth. These facts don't indicate any bit movement in the collet. If the 1/16" end mill slipped there would be a higher area versus being cut to deep. I'm using a CNCRP touch probe with their script. The touch off is always accurate except when using a larger area clearance toolpath.
MoHawk
 
Posts: 7
Joined: Tue Jan 11, 2011 4:41 pm
Location: Mid Missouri
Model of CNC Machine: CNC Router Parts Pro 4824

Re: Help-Pocket with larger clearance tool

Postby adze_cnc » Thu Feb 07, 2019 1:10 am

MoHawk wrote:If the 1/16" end mill slipped there would be a higher area versus being cut to deep.


Steve mentioned bit movement, which could also be the bit moving out. Having once had a handheld router send a bit screaming for the floor (and my foot) because I neglected to tighten the collet enough I can attest to that possibility.

You could try cutting the smaller tool portion of the toolpath first then follow up with the larger area clearance.

Or you could cut with the 1/4" cutter then, if you have space in the pocket for the touch-off plate, set the Z zero to the cut surface. Then manually add 1/8" depth of cut (or measured depth in case it's different) and re-zero through your software. Clear as mud?

Steven
User avatar
adze_cnc
Vectric Apprentice
 
Posts: 734
Joined: Sat Jul 27, 2013 10:08 pm
Location: Vancouver, BC, Canada
Model of CNC Machine: AXYZ 4008

Re: Help-Pocket with larger clearance tool

Postby dealguy11 » Thu Feb 07, 2019 3:49 pm

I can also attest that bits can slip out of the collet...have had it happen many times, especially when the collet is getting worn out.

What version of Aspire are you using? There was a long-ago, short lived bug that affected pocket toolpaths, but this doesn't look like it. Really looks like a mechanical issue to me.
Steve Godding
D&S Artistic Woodworking http://www.dsartisticwood.com
User avatar
dealguy11
Vectric Wizard
 
Posts: 1445
Joined: Tue Sep 22, 2009 9:52 pm
Location: Henryville, PA
Model of CNC Machine: Anderson Selexx 510

Re: Help-Pocket with larger clearance tool

Postby Phil » Thu Feb 07, 2019 4:07 pm

If the problem is wood movement, which can happen as wood is removed, you may want to add double sided tape to the underside of the wood.
Anyhow that is a really nice clock design.

Phil
User avatar
Phil
Vectric Wizard
 
Posts: 2324
Joined: Thu Nov 17, 2005 10:56 pm
Location: Pittsfield, MA

Re: Help-Pocket with larger clearance tool

Postby c1nel1 » Thu Feb 07, 2019 5:22 pm

The fact that a 1/4 in. down cut was used will push down on the material has to be taken into consideration. If the 1/16 bit was an
upcut then it will pull up.
c1nel1
 
Posts: 30
Joined: Sat Mar 22, 2008 7:23 pm
Location: Columbia Falls, MT

Re: Help-Pocket with larger clearance tool

Postby MoHawk » Thu Feb 07, 2019 5:55 pm

I've had the same problem before when using both bits in upcut and both bits in downcut. I'm thinking it may be a problem with the very small bit and the spring loaded touchoff plate.

I'm going to setup a small file and do some testing.

Now I just need to wait for all the ice we have to melt so I can get outside to spray the masked area. My shop is in my basement, so my wife dislike me spraying paint inside.
MoHawk
 
Posts: 7
Joined: Tue Jan 11, 2011 4:41 pm
Location: Mid Missouri
Model of CNC Machine: CNC Router Parts Pro 4824


Return to Aspire - General

Who is online

Users browsing this forum: Adrian, kaetamer, Mirion, Wayne Locke and 28 guests