Material Hold-down when flattening entire surface

I am wondering how everyone holds down their materials when using a fly cutter to flatten the entire wood surface. Do you just use double-sided template tape?

I have a drum sander & planer but would like to start using my CNC to flatten my epoxy inlays to save my blades and sandpaper.

You can either use painter tape and CA glue (check out forum posts or youtube) or low profile side clamps like C3d’s Tiger Claw


It’s been my experience that when flattening, I only needed to hold the piece in place, not down. Maybe just a little 2-sided tape, then holding it in by the sides should be sufficient.

AS @Julien suggested painters tape and super glue is very good. However if your project gets more than 12" square that takes a lot of tape and super glue. I have an SO3 XXL with a supplemental spoilboard that has 2" spacing for 1/4-20 tee nuts. I use cam clamps to hold down large projects. The cam clamps are easy to make but do require a way to anchor them. If you have a newer machine with the hybrid table not everything will line up with the t-tracks for clamping.

I use a long L bracket that mostly stays on my spoilboard all the time. This gives me a good base to line up projects square and gives me an anchor for cam clamps on the opposite side.

long_L_bracket.c2d (296 KB)

In the file are two long L brackets and several cam clamps. The L brackets were designed around a 2" spacing for my spoilboard but youi can simply redesign and move the holes around to match your machine spacing.

The advantage of the cam clamps is they are flat and even if you go over the edge of your project they are made of wood and can easily be replaced.

Warning: my file uses bottom of material and center for the origin. So be sure to change the job setup to your preferences. I use the bottom of material to prevent my spoilboard from being cut up prematurely. Additionally I like to use the center for most jobs because I just like that. Also measure your material and enter that as well. My material was what I had on hand but the thing I do is the large recess hole is always .5" from the bottom of the material so all the cam clamps I have can use the same length bolts without going through to the base board and causing material height problems.

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Thanks for all the info! I will definitely be cutting those brackets and using them.

Here is a reply i made a while ago about what I like to do. I have since started using the L bracket as well but depending on the situation I really like to run an operation to have the CNC create holes that match my threaded inserts in my table and then use those holes to hold down the part for the actual machining.

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I install a Fence on the Wasteboard.
I then use a long clamp on the Y-Axis to hold the piece.

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I’m a big fan of the super glue and painters tape method. If you ever choose to use that keep in mind that as you get a larger workpiece you don’t need to cover the entire surface. If carefull you can lay a few strips and carefully align your project not to glue it to the table. I wouldn’t wallpaper the entire surface of a larger project and not only because it gets expensive in materials but also because you may break your workpiece trying to lift it off the bed of the machine… On a 32" x 20" workpiece i had used 6 strips of tape and tought i would need a crowbar to get it off afterwards. Was very concerned of snapping the board at the glue seams (5 boards glued together). After 2 days of milling that would have been very disapointing.

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This is what I use almost exclusively. Love them for my projects.

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