Computer desk assembly advice

I need some advice on what the best way to join the various parts of the leg assembly. My current plan is to use the Domino XL to attach the legs to the rails(top and mid). I know mortise and tenon is probably best, but I’m not confident enough in my skills to pull it off cleanly, the stock will be about 1-1/4" thick.

For reference, the desk is about 60" long, and will sit about 32" high. I have two rails running lengthwise underneath the top, but I’m also wondering if I should add a rail across the back(in line with the other leg rail) to make sure the legs can’t splay out.

Sorry if this is a pretty basic question, everything else I’ve done has been way overbuilt.

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I do love using dominos. And very appreciative to @AlexRhodes who originally help me discover them.

Recently I learned of the upgraded dominos. I want to get some and try them out before fully recommending them, but see for yourself.

https://youtu.be/53DKsrYqYLY?list=PLFGIE_jCN0y4erQBEt8vV3qkgVs1YzH2f

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Oh wow, a bit more visible than I will go with for this project, but those are very cool. Feels like IKEA building on steroids.

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The IKEA comment is what I am thinking exactly.

Personally, I would single domino each end of the lower rail into the legs. Double domino the legs into the upper rails. That makes for effectively one solid piece for each leg. Then on inside of upper rail to table top use two connectors on each side. That way it’s a very solid connection but can always break table into 3 parts for moving.

The biggest problem I see with this design is when assembled, by whatever method, the joint will be heavily loaded by any side to side movement due to lack of support between the legs. The same reason you have two existing cross pieces to add stability and strength are the same reason for one going across.

I would suggest a cross piece, maybe where the cross pieces are now on the sides, lower would be preferable.

Nice clean design

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I really think you’ll want some sort of truss in the back to prevent racking.

As for attaching the rails to the legs might I suggest a half lap joint. It’s fairly easy with the dado blades and will create a large surface are for the glue. While I think the domino would work fine I think the half lap would be better.

The domino would be more than fine for your side bars between the legs, but I wouldn’t start the taper till after it connects the leg to the side bar. It’ll make your life easier if you don’t have to account for that angle and how it connects to the side bar with the domino machine. The domino machine likes working angles on the Z tilt. No so much on the Y tilt, if that makes any sense.

@apparently_weird glad the domino has proved useful. I still love it for projects.

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First, the overall shape is nice and very doable, with some tweaks. For example, from the picture it looks like you have the top cross piece on either end sitting on top of the legs. I don’t think this will work very well. When your desk surface gets stressed with side to side movement, most of that stress will be concentrated in the joints connecting the leg to the top cross piece or the top cross piece to the underside of the top. Better to have the crosspiece connected to the side of the legs with a domino, or using a half-lap as @Alexrhodes suggests, which I agree would be a simple and very strong joint. (Make that half lap joint before you cut the taper on the legs!)

Traditionally, the top cross piece is part of a four-sided “apron” that connects all four legs together, and the assembly should stand freely on its own with the top just sitting on top of it. The front and back parts of the apron prevent the table from rocking side to side and the side aprons keep it from rocking back to front.

If you don’t want the front and back aprons, you might be able to put a single stretcher down the middle of the table, creating an “H”. However that arrangement isn’t as strong and might require addition bracing.

I think the most important thing to keep in mind when building a table is that the top is almost ornamental. It doesn’t add any structural benefit. It simply floats on top of the legs. If you concentrate on making the legs and whatever apron arrangement you come up with sturdy, your desk will be fine.

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Definitely need the apron on all four sides and you’ll probably want the legs removable so you can transport it.

These photos are from a coloring table, little taller than a coffee table, made for our daughters about 28 years ago, it got passed on to a few friends and back to us a few years ago. Temporarily used for a printer stand till it hopefully will be needed as a coloring table again.

Note that the top floats on the apron so it doesn’t tear itself apart from seasonal humidity changes. The top will expand and contract more than the apron. The cleats screwed into the top have a tennon that fits in the dado groove on the apron.



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Thank you guys for all of the advice! I added the back rail on the legs and changed the style of where the connection would be on the legs. I didn’t model the half lap joints because I’m lazy, but I believe I understand how to go about that.

As for the front skirt, I didn’t show it in my initial view, but I do have a rail modeled under there. Honestly I just want to avoid banging my knees! I attached a new picture, does that look sufficient for strength?

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Much better. That will prevent or greatly reduce the racking @AlexRhodes referred to.

Phew! Thank you!

It has been a while since I have used a crosscut sled at DMS, I know at one point one was known to be out of square. Is there a particular one for dados, or is this a job for a miter sled?

Are there dados in your design above?

I’m a metal worker type, but structural dynamics are the same for woodworking, metal, plastic, etc. Let the wood workers guide you on how to join them. I know about the various joints but it has been several decades Edit: make that several score, since I’ve made them.

I probably didn’t phrase that correctly. I meant using the dado blades to cut the half laps.

Edit: I need to learn definitions better, I guess it would be more accurate to say the half laps for the top rails and cross laps for the mid-leg rails.

Sorry, my fault. I’ve been following the thread…it was immediately obvious once you said it.

You can use a miter gauge without a sled if you want…should be fine. We used to have a dado sled but it may have bit the dust…always a good opportunity to build one, though:–)

Reminder, that you can make dados, and in this case rabbets, with a router or on the router table, too. Not necessarily the best solution in this case, just reminding.

Rabbets! That’s where I was messing up.

I do have more experience with router tables, I just figured at this size the dado blades make sense. Seems like a good opportunity to learn :slight_smile:

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How come we don’t have a hollow chisel morticer? Too much abuse? Thats how i would do the strechers between the legs, the mortices can be cut by hand. Tenons on tablesaw.

You need a skirt or apron piece across the front to tie the legs together.

I had to sit down and look at the drawing to make sure I wasn’t missing something. I’m still having a bit of trouble understanding the joinery at the top corner(joints 1 and 3 on the picture). Am I thinking about that right?

Found a picture of how I interpret the correct way to do the corner joint.

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I’ll leave it to others with fuller experience to comment on the joinery, but I’ll note this oft overlooked technique for gluing up joints involving end grain surfaces, called “sizing” (this would include miter joints):

http://www.titebond.com/resources/use/glues/applicationtips

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Excellent point! The top will expand and contract front to back during changes in season and humidity.

When I got to DMS, this was the first thing I noticed. Alongside all of these high-end power tools I expected to see a floor standing hollow chisel mortiser, but we don’t even have a table top mortiser. I was told the reason we don’t is because we have the Domino. I haven’t used it yet–and I harbor some skepticism about floating tenons in general–but I have been told the Domino is the real deal. I’ve been meaning to bug Patrick into giving me the sales pitch.

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