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Jay Michaels
12-02-2019, 2:54 PM
I'm working on a pair of desks using the plans drafted by the man who designed and built this desk:

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I have much of the casework complete and the legs are already milled.

My remaining question is how best to affix the legs to the case.

The only differences between the desk in the photo and the ones I'm constructing is that mine are a bit beefier -- just a few inches longer (the main case is 41" long) and the walnut I'm using has an actual thickness of ~22mm (about 0.85") for all the parts of the case and the legs.

I believe in the original (in photo), the legs are attached with screws from the outside, with the holes filled with matching plugs.

I like to avoid screws when I can, but I realize they are likely the most sound method of affixing these legs. Would any domino (mid-size, or even up to the 10mm--the largest that can be used in the Domino 500) suffice, or would that be too risky?

Jamie Buxton
12-02-2019, 3:09 PM
Glue. You have a nice big glue area. If you want, you could add screws, with the head on the inside. But they’re not really necessary.

Erik Loza
12-02-2019, 4:52 PM
Screws from the inside.

Erik

Derek Cohen
12-02-2019, 6:53 PM
Screws from the inside, along with glue ...

https://i.postimg.cc/1R8fY50H/52.jpg

https://i.postimg.cc/nVNC8b0t/53.jpg

https://i.postimg.cc/2S76Bqmz/54.jpg

https://i.postimg.cc/jjqj6sdy/57.jpg

I had reservations at the start, originally planning to use loose tenons. It turned out to be a very strong join.

Regards from Perth

Derek

Jim Becker
12-02-2019, 8:06 PM
My retro vinyl record stand I made for a commission awhile back had a similar leg arrangement. I put threaded inserts in the inside of the leg assembly and use bolts from the inside of the case to hold the leg assemblies to the body. The further advantage was that it was then technically "knock down" should the client ever need to move it and want to take advantage of disassembling. Here are a few photos from that project that might be helpful to you.

https://6zewsg.bn.files.1drv.com/y4m6qKwfAdLVZX_C1HTCKIGrjIxtNc4FkR8QrMH6Gl-gEgTT5tpAAJ65STOs9Hq9pPFVt3CqlnhDTO_1-w_nZk4KQzLYsXeQwl23vM_jT9Cf2USHE5YpFyKgsBkafCkecwQ QFCsMrWYi5VVoyYidJCal-fM5WXdmcOG8Aj-pcKRqfErBfCvg1A7WFmkjuhUh-7nFK6tvLiX484CDVgf4NFACg?width=660&height=660&cropmode=none

https://5tewsg.bn.files.1drv.com/y4mwwoXuUEuthzgqGFAshTS6aoAZzqtFIkZ-ir_tcaA7roPrYDXXHPWqz4Oa2Zt6hq3-xIQNUpDfLNV2RNh1ds_K_cXWvCyu-ba6RrR2cXhhSNmKW_OqOWABVclnnyLTpfoNMnCQCFTRe77JlvQ AFLauzWxNxx9eE9koQ1jB5XoUkSrNhEQX5uIuCDynBSO5feAD4 _snQ4b-QTKx6cegcSV9A?width=660&height=660&cropmode=none

https://5thljg.bn.files.1drv.com/y4mRhGkV0bwOtrksuk8RcJ_Q8StojwlPSbTPatEukmZO55LASf rPbpiW3mLoZcMESQVVZyZ-FL837XWRrBUQGag-cExz8GrKf4FlAAsD73qzDUlLlpLIznfEqqbLl7CzgZTH2BBX6H kVOkNhK2y5UP_H0mxc4b8cgdeGCGZu44vPrqFVW685U8YKoWUZ FW51ZfT5Hn3W3YPRObypTxIGGtQ1Q?width=371&height=660&cropmode=none

Tom Bender
12-07-2019, 6:43 AM
Yeow! that desk has a Huge cross grain problem. The sides vs the top, bottom and shelf will cause problems if not dealt with in the joinery. Derek has built his desk with the grain running around so it all moves together. Yours needs to be joined in a way to let the lengthwise parts float relative to the side parts. Could you redesign to follow Derek's example?

Jim Becker
12-07-2019, 9:41 AM
Yeow! that desk has a Huge cross grain problem. The sides vs the top, bottom and shelf will cause problems if not dealt with in the joinery.

That's a good point as in order for it to work well with seasonal movement, the top and bottom panels will need to be able to move independent of the side panels. There are a number of ways to do that, but all of them involve some precise work that allows movement without impeding structural strength.

Jay Michaels
12-09-2019, 10:15 AM
Yikes - now you all have me nervous. I see exactly the problem you're talking about -- it is something I just didn't *see* when I saw the photos online and started building. Thank you for bringing it to my attention. I mean that sincerely.

I have almost every piece milled down to size and many parts already ready for dominos (for this portion, I'm using the 6x40mm dominos). On one surface, I cut the usual (small) slot size for the domino, and then on the matching part, I cut the "middle" width (the slightly wider setting on the domino) to receive the tenon. (If you look closely at the photo, you can see the mortises on the side piece are wider than the mortises on the panel). But I haven't yet glued up the case or the top/hutch yet.

Here's what one of the panels looks like, with the side sitting on top - you can see where I've already cut the mortises. (I've been putting a few coats of finish on that one surface that you see before the glue-up since I figured applying a wipe-on finish inside the finished case would be difficult). This is a bottom panel for the case; the top panel that will go with it -- the writing surface of that desk -- has no sapwood like this panel does.

421250

421251

So my question is this: keeping this same general design intact, I'm pondering how best to accommodate seasonal movement. Rather than applying glue all along that joint that you see in the photos, which was my original plan before I saw the movement issue, perhaps I stand a better chance if the dominos themselves receive no glue (they fit rather snug, though not impossibly tight) and I only apply glue to the middle ~6-8 inches or so of the panel? Would that allow the panel to then expand/contract along the front/back sufficiently to prevent splitting later? Absent dramatic changes to the plan and the joinery, are there other recommendations people have to mitigate my risk?

[I realize that may introduce its own set of problems if either panel cups -- since it won't be glued to the side panels along the front/back -- is that a risk worth taking to mitigate the possibility of the panel splitting if I glued all along that joint?]

For reference, the panel is walnut, 22mm thick (about 0.85"), and 23" wide along that joint. Each panel is a glue-up of three boards, each around 7-9" wide. I realize the flat-cut nature of the grain isn't the most stable. It comes from a tree that came down on my property in the fall of 2017 that I had milled by a local sawyer - it has been stickered and stacked drying indoors since being milled about 26 months ago. It seems very stable.

Thank you all - the people here have all proven to be so incredibly helpful; I greatly appreciate it.


PS - I'm going with the threaded inserts and screws for the legs -- fantastic idea and I love the bonus that it can be broken down if needed.

Jim Becker
12-09-2019, 1:25 PM
If that's a breadboard end or similar, only glue the Dominos in one piece except for the center one that should be glued on both sides. The Dominos glued to only one sude should be centered in the wider mortises on the other side so pay attention when you install them. Clamp it all together and then pin the Dominos on the non glued side from below the same way you would for a traditional breadboard end. The only change to this would be if one side of the panel will be dead flat against a wall or otherwise not be ideal for any movement in "that direction". Change the fixed tenon/Domino to the last mortise (a tight cut in that case) at the side that should be fixed and then any movement will be completely toward the other "front" edge.