Introduction: DIY Biscuit Joiner XL

When a standard biscuit joint doesn't cut it, you need the Biscuit Joiner XL. The strongest biscuit joint in the world.

Step 1: Project Background

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The good old biscuit joiner. Great for joining up boards, panel glueup, and more. But sometimes little biscuits just aren’t strong enough. I’ve decided to take matters into my own hands, by making the biscuit jointer XL.

P.S. If you haven't caught on yet; yes, this is an April Fool's day joke :P

Step 2: Cut Plywood

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All you need for this project is a plunge cut saw, and some plywood. I’ve got this little scrap piece, that’s the perfect size.

The rest will be cut from a sheet of 3/4-inch baltic birch plywood.

Step 3: Smoothing Part 1

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There was a little bump in the sheet of plywood I’m using.

Just going to knock it down with a block plane.

Step 4: Smoothing Part 2

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Now I’ll just surface everything for this project to 220 grit.

A hand sanding block is used on the edges.

Step 5: Cross Cutting

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I set a flag stop at the mitre saw and batch out all the cuts.

Step 6: Specialty Cutting

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The part which lays on the stock will be beveled. This is how you make a 45° bevel cut when you don’t have a table saw.

Step 7: Drilling

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This piece will have holes drilled to accept the rods on the saw.

Step 8: Mistake Fixup

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Okay, I attached that to the saw, but small problem: there’s a little bump here. Shouldn’t have drilled those holes right in the center.

Easy fix for a router with a flush trim cutter.

Step 9: Drill & Tap

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Now I’ll drill and tap two more holes so machine screws can secure this part to the saw.

Step 10: Joinery

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Just in case this project isn't controversial enough, I’ll use a domino joiner to join these parts up.

Step 11: Dry Fit & Glue

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Dry fit is good.

Now the more relaxing part of this project… the glue up!

Clampy, clamp, clamp.

Hmm, maybe one more clamp.

Step 12: Adding Reinforcements

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Just going to cut some reinforcement triangles here, for the edges.

Some more glue, and I’ll take these in with a pin nailer so they stay in place.

Step 13: Scrape Glue Squeeze-out

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Scraping off the squeeze-out.

Step 14: Add a Holding Knob

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The final piece will be this knob, so it’s easier to hold the tool against a workpiece.

Step 15: Setup/Adjust

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So more or less, this is how it’s going to work, and the height is adjustable.

I set the height with setup blocks. Great!

Step 16: Joining Time!

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Now here’s big two-by-six I need to join.

Finally, I present to you this Biscuit Joiner XL.

Step 17: Cut Biscuit Slots

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I suppose this part is pretty self-explanatory, although I’ll probably go back and make these slots a little bit wider.

Yeah, I’ll make a few more cuts until the slots are 1/4-inch thick. Readjusting the position.

I repeat this until all excess material is clear.

Step 18: Cut Biscuits

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Now I need my biscuits. I’ll trace out the blade diameter onto 1/4-inch plywood, and then cut it out. The blade packaging came in real handy for this!



There you go: strongest biscuit joint in the world.

HIGH FIVE for reading!

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Tuomas Soikkeli made it! (author)2017-09-26

I kind of made it. Used angle grinder and suitable wood cutter.

Pictures are missing the height adjustment plate. Made this for cutting metals, but it turned to "multitool" at the end. This was my inspiration to start thinking the whole thing. Thanks!

Toolify (author)Tuomas Soikkeli2017-09-26

Awesome! That one was made as bit of a joke, but I'm glad it could inspire :)

Yonatan24 (author)2017-04-05

You should add that it was an April fools joke in bold - extreme kickback hazard!

Toolify (author)Yonatan242017-04-05

Yes, kickback hazard is real – that's why I didn't plunge in very deep.

Tuomas Soikkeli (author)2017-04-05

That's not a bad idea at all, even you said its a joke. With a twin blade saw there's no risk from a kick back either. Those biscuits are very thin actually.

Toolify (author)Tuomas Soikkeli2017-04-05

Hadn't heard of a twin blade saw. Googled it, looks very cool :D

Thanks for the tip!

About This Instructable




Bio: Hi I'm Kriss! I’m a 20-something that likes to build tools, jigs, and other random contraptions with wood.
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