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Coyote Jim

Clamping a half lap joint.

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I'm still a bit green and this is my first ever half lap joint project.

I need them for shelves that will be used for this:

5a9eb4387a1c0_stuffedanimalstorage1(2).thumb.jpg.06c0486089fdcb3bf8026d601a76949b.jpg

I will be making a much better version of what is pictured above. The corners of the "shelves" will all be half lap joints.

I made a test to make sure everything was dialed in (which was a good thing because my first test was very out of square, putting a piece of tape on my miter gauge fixed that!).

I clamped up the test piece like this:

IMG_20180305_192709.thumb.jpg.6df0b85ba92aff9ac56ef71a9570915f.jpg

IMG_20180305_192720.thumb.jpg.7af7e950c019a0c9b3b68f7c4beedf8c.jpg

I used 4 clamps for one joint and I still feel like it was not enough. Very fiddly trying to get it all set.

Do I need the long clamps (along the long grain) to make sure it stays tight against the shoulders? Should I use more than two clamps to sandwich the joint?

I don't want to have to do only one joint at a time. (4 joints per shelf x 3 shelves x 1 hour for the glue to set up = 12 hours.)

Anyone have any tips for me on how to do this glue up properly and not having it take too long or use dozens of clamps I don't have?

My (second) test joint ended up looking pretty good even though I did not like the way I clamped it.

IMG_20180306_071308.thumb.jpg.21aae7a3c39fd75e35bfa6615dc38ade.jpg

Any insights would be awesome.

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Jim, I think more than one clamp per corner is an overkill. I would use one per corner, locating it outside the frame and in a position so as not to block your tape when you check the diagonal measurement from opposing corners to check for square. Just do one corner at a time and get it square before going to the next, using Titebond III for extra working time.

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I would clamp vertically from the outside of the frame so it was easier to check square on the inside. Do both halves of a frame glued with TB 1,  wait 30 minutes and remove the long clamps but not the vertical ones then assemble the entire frame. 

I would use a single parallel clamp vertically if you have them. I use my short K body Jr clamps more than my long full sized K Body clamps. 

If I had a bunch of those frames to assemble after doing a few to get the clamping procedure figured out I would switch to Dap Rapid Fuse glue. It gives you 5 -10 minutes to get the joint aligned and clamped and after 10-15 minutes in the clamps the complete frame could be assembled. 30 minutes is completely cured but the shorter time in clamps is plenty to switch to assembling the next frame.  It's a cyanoacrylate formulated for wood. Dries clear and after sanding has no affect on stains and finishes.

16806F85-CE29-44FA-8097-9D13F998CFA8-5000-0000057BBEDF69C3.jpeg

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I have less experience than the other 3 poss right before me but I rather like the 3 clamps at each corner (one vertical and 2 horizontal).  I would move the vertical clamp to the outside for the reasons given.  Clamp corners 1 and 3 nice and square and then clamp corners 2 and 4 to complete the assembly.

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It took me a while to get around to this but I finally got everything glues up.

Using suggestion from above my final glue up looked like this:

5aa6d36baeace_IMG_20180311_175515(1).thumb.jpg.32ee930920b5166c9487875856707a05.jpg5aa6d36eeb194_IMG_20180311_202102(1).thumb.jpg.15ac2515bfe99defcf8f9aaf01800c30.jpg

I only had 3 of them so this did not require too much time.

Thanks again everyone for your suggestions. It really was a big help to me.

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Looks like a quite effective clamping strategy. Ya just gotta do the best you can with the clamps you have at hand. Doing a test dry run is always smart.

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