Question about coping sleds

[Bruce Day]

I was cutting some bridle joints on the table saw the other day, cutting the slots on the end of the board ( 2 1/2in), taking about 1/8 off with each pass when my biggest nightmare came true, kick-back right in the face. Needless to say it knocked me out and I ended up with a hair line fracture of the left checkbone, just missing my left eye. My neighbor was there and he said it happened so fast he couldn't believe his eyes. I was standing there one second and the next thing I know he was sitting me up against the wall. I don't know what I did wrong, I was using a jig that had more than ample rear and side support, using my Frued box cutter blades alligned for 1/4in width, and like I said cutting about 1/8in with each pass, PLUS I was standing to the left of the board I was cutting, I thought and still do believe I was doing everything correct and safe. Would using a decent coping sled be a better and safer option? I have big enough slot cutters to use. I've always taken extra care when standing boards up to cut. After this incident, I don't have the cajones to finish the door. Thanks in advance for any advise or thoughts. Could there have been a chance I hit a void in the wood? I was cutting red oak.

[Dave Zellers]

No way to know from your description what went wrong but somehow the wood moved enough for the blade to catch it and spit it out.

If you can alter your jig to clamp the piece in place I would do that, otherwise get a tenoning jig for that type of end cutting. When you do, and with the proper rip blade, you will be able to stop nibbling 1/8" at a time as you are now doing.

[Rod Sheridan]

Bruce, glad your injury wasn't worse and that your eye is fine.

Bridle joints should either be cut on the band saw or shaper, a table saw isn't built or guarded for that sort of work.

End View.jpg

Here's a fuzzy photo of a bridle joint cut on a band saw, the only part that has any other work is the bottom of the slot, I cleaned it with a chisel, the faces are straight off the saw, it's almost as good as one made on a shaper......Rod.

[Robert Engel]

Glad you're not hurt worse. Close calls like this remind us we are in a dangerous hobby.

If I'm understand you, you did this freehanded and probably what happened was as the piece passed thru the cut, it was tipped enough to cause the blade to catch front corner of the slot to tip into the blade and things go downhill from there.

This cut can be safely done on a TS. Any number of tenoning type jigs would work for this operation. Best to have one that employs a clamp.

Personally, I like the Steve Latta-designed tenoning jig. Here's a link to a build. I believe the original article is in FineWoodworking.

[Bob Leistner]

You should have a tenon jig/fixture to cut bridle joints. Quite a few different companies have made them with varying degrees of usefulness. Look up Delta 1172 to see one of the better ones.

[Mike Ontko]

Bruce, glad to hear that you're still in good shape and managed to avoid any serious injury.

+1 on the use of a dedicated tenon jig, especially one with strong clamps. I would also add that keeping the bottom of the piece elevated off of the saw table would help.

[Jerry Miner]

I was using a jig that had more than ample rear and side support....

Can you post a pic of your jig? Sounds like the support and stability were not quite so ample.

A tenoning jig should allow this cut to be made safely. Was the work clamped to the jig?

[Bruce Day]

Jig got tossed but kind of reading what everyone has posted I think I should feel like a different method (tenon jig) should have been a safer option. I've caught myself thinking that the further I pushed the piece away from me the better the chance I slightly shifted the board and it became unstable, plus I was standing a good distance to the left of it. What scares me the most is how fast it happened, no warning, no nothing. I'm also thinking now another error on my part was I didn't have it clamped tight enough. Thanks to all, you guys have helped a ton

[Rod Sheridan]

Hi Bruce, whether home made or purchased commercially, I was never able to solve the issue of blade guarding when cutting tenons or bridle joints on a table saw.

The band saw, or shaper will perform this task much more safely than on a table saw.

On a shaper the cutter is guarded by a sliding plate, through which the work piece contacts the cutter, the cutter is completely enclosed while you're loading or unloading the piece.

here are a few photographs of making tenons on my shaper.
Cutter and Tenon Hood.jpgWorkpiece Clamped in Place.jpgCutting the Tenon.jpg

Although people do cut tenons on a saw, in industry you would lose your job for doing that, for good reason, an unguarded blade a couple of inches high will take your hand in a flash....Rod.

[glenn bradley]

I do bridal joints with an inexpensive commercial tenon jig. The jig puts my hands a good 6" away on the other side of 15 pounds of cast iron.

GnG Low CoD (192).jpg

The material is clamped to the jig and backed with a backer board. The jig, being well aligned, assures a true path past the cutter. I do see the quick, shop made tenon jigs shown in magazines and in videos but, would not perform this operation without the material being securely clamped to a well aligned platform. JMHO.

[Jerry Miner]

The band saw, or shaper will perform this task much more safely than on a table saw.....Rod.

Rod-- I appreciate your comments about safety, but can you really cut a 2-1/2" bridle joint on your shaper? (Your pics show a much smaller stub-tenon)

[William Shelley]

Rod-- I appreciate your comments about safety, but can you really cut a 2-1/2" bridle joint on your shaper? (Your pics show a much smaller stub-tenon)

Sure. You just need a slotting cutter with a large enough diameter. You may need to build a wood guard/fence that can accomodate the larger diameter cutter if the stock guard can't fit it.

[Jerry Miner]

That makes sense, of course. I guess I've just never seen a shaper cutter that big. What would it take-- 8" diameter? Is there an upper limit to diameter for a shaper?

[Rod Sheridan]

Rod-- I appreciate your comments about safety, but can you really cut a 2-1/2" bridle joint on your shaper? (Your pics show a much smaller stub-tenon)

Sure, here's the tenon cutter I have for that, 220mm diameter, 74mm depth of cut. Fits just fine in the tenon hood as that's what it is designed for.

For the bridle portion I use a slotting cutter.

Here's the rebate head for the tenon

http://us.feldershop.com/en-US/en-US...B-HW-oxid.html

Regards, Rod.

[Glen Gunderson]

A tenoning jig for a table that securely clamps the wood in place and keeps your hands far away from the unguarded blade is going to be your safest bet without spending a bunch of money.

A shaper with a sliding table is a better option, but unless you have one already it's a pretty expensive proposition. But when you're cutting into the end of a longer piece of wood, doing it horizontally is a better option than standing it up on a table saw.

Personally I usually stick with mortise and tenon joints for this application. Doing it on a table saw never felt safe to me and I don't have a shaper.