dropping in on a stopped shaper cut

[Kevin Jenness]

I am making parts for some closets. The center dividers supporting adjustable shelves require a dado to accept a concealed cleat at the back and floor. Had I planned correctly I could have run the bottom grooves through and then banded the front edge. As it happened, I had to to do a stopped cut, so I thought I would post some photos of the process. Suggestions for improvement are more than welcome.

Stopped cuts are potentially hazardous and should be thought through before undertaking. "Dropping in" refers to swinging the workpiece into the revolving cutter and continuing the cut. It requires a backstop for safety. The heavier the cut the greater chance for kickback.

The only groover I had that would make the cut 3/4" wide and 1 1/8" deep was 1/4" thick so I set its height once for the outer cuts, so the groove would be centered, then raised it 1/4" for the center cut. In one direction I entered straight in and hand-fed the pieces until the banding aligned with the fence cutout, then pivoted the trailing edge away from the cutter. In the other direction I rested the banded edge against a stop screwed to a fence extension, pivoted the leading edge into the cutter and pushed through the cut. The free end of the workpiece was supported by roller stands.DSC_0688[1].jpgDSC_0690[1].jpgDSC_0689[1].jpgDSC_0691[1].jpg

[Joe Calhoon]

Kevin,
I’ve done it that way many times without incident. It is safer to drop in from the tail as this page from a German safety manual shows. Gives a little more control to reduce chance of kickback. The blocks they show in this picture are just a setup aid.
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I like Sweed supports for shelves and always forget to make the cut before banding!

[Lee Schierer]

You have to be extra careful when "dropping" a piece of wood onto a moving blade or cutter. It is best to have stop blocks in place to prevent any chance of kickback or self feeding. It is best to make shallow cuts when doing this as the deeper the cut the greater the chance for the cutter to grab the piece of wood.

[Kevin Jenness]

Joe, thanks for that. I had seen that before but forgotten it. I can see that pivoting from the front allows for a more controlled entry. With a deep cut that starts near the end of the workpiece it might require a quite wide tail stop or making the cut in a couple of steps.

Lee, you are absolutely right. Thanks for emphasizing the point. I have edited my original post to make the kickback potential clearer. You can see my stop block in the third photo.

[brent stanley]

Joe, thanks for that. I had seen that before but forgotten it. I can see that pivoting from the front allows for a more controlled entry. With a deep cut that starts near the end of the workpiece it might require a quite wide tail stop or making the cut in a couple of steps.

Lee, you are absolutely right. Thanks for emphasizing the point. I have edited my original post to make the kickback potential clearer. You can see my stop block in the third photo.

It was probably almost 10 years ago Joe reminded me/us of that technique and I tried it and it felt really good. I'd been shown it in England 20 years ago, but forgot it. Like you say though, when it's a deeper cut closer to the end, the geometry gets awkward and you need to be careful.

[Warren Lake]

had to do non through cuts many times on the table saw with dadoe blades, mostly no stop. You can also set the blade in place and raise it up into the material knowing when to stop. Pencil line showed where to not go too far. Sometime was forward of the line and moved forward as dropping onto the cutter, less tendancey for it to want to kick then drop on again and most of the material is removed. Always came down from the front side on the saw as that is what was convenient. Different on a saw than on a shaper plus have the non kickback heads or less grab than the old aggressive dadoe blades.