Clear Pocket Profile Pass issues- please assist
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Clear Pocket Profile Pass issues- please assist
I'm having consistent issues regarding pocket toothpath. Currently I'm using a 1/2" 2 flute end mill and keep coming up with a .002" deeper cut on the profile cut last pass. When using a 1/4" end mill I get the same although about .001+ deeper. The issue is consistent across a 21" x 48" job. I resurface my work top twice now ending up with same results. Any ideas?
- FixitMike
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Re: Clear Pocket Profile Pass issues- please assist
It sounds like machine deflection. It doesn't deflect so much on the profile pass because less material is being removed. Does the difference go away if you recut the pocket? Another possibility is wood movement after the pocket is cut before the last pass. It happens.
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Experience comes from bad judgement.
Experience comes from bad judgement.
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Re: Clear Pocket Profile Pass issues- please assist
Thanks for responding. I've had the same thing happen on other projects. This time I ended up skipping 'last pass' and making a separate profile cut. Both pocket and new profile cuts were level, clean, no issue. It only happens when I use 'last pass'. I have not used 'first pass'.
- IslaWW
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Re: Clear Pocket Profile Pass issues- please assist
Are you using a down spiral bit?
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- martin54
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Re: Clear Pocket Profile Pass issues- please assist
Is your last pass in the same direction or are you reversing the direction for the last pass ?
- WaltS
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Re: Clear Pocket Profile Pass issues- please assist
I had this same thing happen recently on two plaques I made. Last pass profile cut of pocket was deeper than pocket. I recut the pockets and the same thing happened. Used a 1/4" downcut endmill. Never had that happen before. Still scratching head.
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Re: Clear Pocket Profile Pass issues- please assist
Have a look at the G-code. Even if you're not G-code fluent, it's pretty easy to check if the depth of the pocket is the same as the depth of last pass profile.
I am pretty sure they are the same as Vectric programs are very reliable, but you may have encountered a specific case, who knows.
If they are the same the issue comes from the machine controller of from a physical problem on the machine.
I'd bet it's the second case. So forget the software and think of the physical causes like the ones Mike, Gary and Martin mentioned. You may also have a loose collet or lose steps on the Z axis.
Change parameters, perform some tests to identify the culprit. The first thing to do is checking Z0 before and after the cut. If it has changed, your bit has slipped in the collet, you've lost Z steps or your material moved (depending on your Z0 reference: machine bed or material top).
I am pretty sure they are the same as Vectric programs are very reliable, but you may have encountered a specific case, who knows.
If they are the same the issue comes from the machine controller of from a physical problem on the machine.
I'd bet it's the second case. So forget the software and think of the physical causes like the ones Mike, Gary and Martin mentioned. You may also have a loose collet or lose steps on the Z axis.
Change parameters, perform some tests to identify the culprit. The first thing to do is checking Z0 before and after the cut. If it has changed, your bit has slipped in the collet, you've lost Z steps or your material moved (depending on your Z0 reference: machine bed or material top).
Best regards
Didier
W7 - Aspire 8.517
Didier
W7 - Aspire 8.517