Miss Cuts w/3D Cutting

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Tomdigi
Posts: 13
Joined: Tue Jan 12, 2016 10:19 pm
Location: New London, NC

Miss Cuts w/3D Cutting

Post by Tomdigi » Sat Jan 12, 2019 8:38 pm

This is a test run on mdf of a plaque I'm making for a customer. The attached photo shows areas that have ramped up and 2 areas that have horizontal lines cut. The bit is a 0.125 Ball Nose, running at 150 ipm.

Nothing shows up on the preview in either the Z plane or X/Y plane that would indicate this problem. None of this is a REAL problem as they can be sanded out if repeated on the final.

Any thoughts greatly appreciated.
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WillAdams
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Re: Miss Cuts w/3D Cutting

Post by WillAdams » Mon Jan 14, 2019 1:15 am

Stuff like this can happen for a couple of reasons:

- mechanical --- check the Z-axis belt tension, squareness of the machine, plumb of the router
- feeds and speeds and direction --- the machine may dig in / get pushed out of a cut based on climb/conventional milling --- consider leaving a roughing clearance and making a finishing pass
- material springs back --- MDF and some other materials will compress as/where cut, and depending on how long there is between passes may or may not spring back in-between --- optimize order of cuts or leave a roughing clearance and make a finishing pass.
Shapeoko 3XL #0006 w/Makita RT0701 Router w/0.125″ and ¼″ Elaire precision collets
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Tomdigi
Posts: 13
Joined: Tue Jan 12, 2016 10:19 pm
Location: New London, NC

Re: Miss Cuts w/3D Cutting

Post by Tomdigi » Mon Jan 14, 2019 10:13 am

WillAdams, thanks for the suggestions. Will try again after checking all you suggested and will do a roughing pass. You can always be counted on to supply analysis and suggestions. Thank you!
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CrazyBillybob
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Re: Miss Cuts w/3D Cutting

Post by CrazyBillybob » Mon Jan 14, 2019 2:43 pm

While your checking every thing will Mentioned it's a good time to check and make sure all your set screws are tight. It's a good practice to check them every so often, especially a few runs after you set them for the first time. Locktight helps but if they are a little loose cutting makes them looser.

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