Joint to use for table top

[cyberbum]

Hi guys,

Beginner here I was wondering what kind of joint I should use for a table.
I don't want to have any visible supports, but I am wondering about its stability (wobbling left to right).

The table top 1 1/2" thick, 60" long, 16" deep. The legs are 16" deep, 27" high, 1 1/2" thick.

I am thinking of just dropping the table top onto the legs with biscuits/glue, but like I mentioned, I'm afraid the whole thing is going to wobble left/right.

Anyone have any suggestions?

Thanks!

[scorrpio]

I'd consider sliding dovetails. They should hold the top real well and prevent it from cupping. And should be a lot less prone to wobble. Not as hard as you might think. Cut dadoes in the tabletop, then rout their sides with a dovetail bit. Use same bit to rout the recesses along leg tops. If you want to hide the joinery, you can rip thin strips off tabletop sides, and once the legs are in, glue the strips back on.

[Ken Weaver]

If its a trestle style table, you could consider a cross member with mortise and tenons (like the pic below). If you'r put off or intimidated by the sliding dovetail (which I would be) it might be a good start.

[LarryG]

What sort of table is this? If it's something like a mostly-decorative front-hall table -- you know, just something to drop your keys and the mail onto when you come in the door -- then you might well get by with a simple joinery method (biscuits, mortise and tenon, the sugggested sliding dovetails). But if the table will be actively used and can get knocked around any at all, those legs will have a long enough moment arm that any 90 deg joint will be hard pressed to take the strain.

Splaying the legs out at the bottom, if your design will permit that, would help. Better yet would be to add a stretcher to tie them together.

Remember that the grain in the legs will have to be oriented the same way as that in the top, so the entire assembly can expand and contract together.

[LCHIEN]

For traditional table working I like mortise and tenon joints.

If you aren't too comfortable with M&T or devtails suggested recently, then a simple way that doesn't really show (looks as good as M&T or devetails or biscuits) that requires less investment and work is the kind of brackets sold by Rockler (instructions with illustrations linked below):


http://images.rockler.com/tech/24281-299.pdf

features simple work, no tenons, no biscuit cutters, no router
just screwdriver and drill and saw (to make the slots)
you'll nned the bracket, some screws and the special hangar bolt (wood screw on one side, macine screw on the other) and some nuts (Wing nuts are good).

[drumpriest]

I would personally do M&T or loose M&T and brace the corner underneith using either a wood block and some screws (oversized holes and pan head allows for movement, no glue), or with a brace like Loring shows.

[cyberbum]

Better yet would be to add a stretcher to tie them together.

What is a stretcher? Sorry for my noobness

[LarryG]

What is a stretcher? Sorry for my noobness

Members that connect legs, down below the table top, usually six or eight inches off the floor (although this can and will vary). See the picture that Ken posted ... there are short stretchers joining each pair of legs at each end, and then a longer stretcher between the two short ones.

Don't apologize for not knowing something. No one knows it all. Every one of us is still learning, all the time.

[JR]

What is a stretcher? Sorry for my noobness

This might be a good time to suggest a trip to the library. There will be several books on making furniture, which will do much more for you than the cursory answers you'll normally get on-line.

Page through those books for 30 minutes or so and you'll start to get an idea of what styles you like and what joinery you think you'll be capable of doing.

JR

[cyberbum]

Yeah I think I'll read up some more, never thought woodworking was such a technical field, as much as programming in some senses, except you have to rely on your physical skills as well

[Tom Miller]

So, if I'm understanding correctly, the "legs" are pieces of the same thickness and width as the top, and you want to butt them into the underside of the table. Is that right? If so, you're right to assume that there'll be little protection against racking forces.

Could you get away with some kind of cross member (stringer) just under the table top, but towards the back? It wouldn't have to be more than 3" wide (tall), so it would be visible only at the lowest of viewing angles; you'd still have the visual effect in front.

This crossmember could be attached to the legs very simply (e.g. by means of pocket hole screws) from the back, or by sliding dovetail, etc. etc. depending on your level of proficiency.

Regards,
Tom

[JimD]

An apron also supplies significant strength to a table. These are pieces 2-3 inches tall directly under the top that tie the legs together. The top is then fastened to the apron rather than the legs. I now use mortise and tenon but our computer table is more than 10 years old and the legs are tied to the apron with biscuits. It is holding up very well. Biscuits take a tool that costs around $100 minimum but they are very easy to do. They do not show.

A kitchen table probably needs more than an apron for support but it is enough for our computer table and will work for end tables or coffee tables.

Jim

[cyberbum]

So, if I'm understanding correctly, the "legs" are pieces of the same thickness and width as the top, and you want to butt them into the underside of the table. Is that right? If so, you're right to assume that there'll be little protection against racking forces.

Exactly.

I was wondering actually...how about using a miter joint with biscuits? I read on the web that this joint is not actually strong, but in my case it could solve the rocking problem. I have a biscuit joiner, so at least I have the equipment.

From what I've seen, a dovetail would probably be better, but it's out of my skills for the moment

Or what about a lap joint?
http://www.woodmagazine.com/wood/sto...ef=wd21&page=2

Would seem to fix my rocking problem, and not too hard to do.

[LarryG]

A lap joint would be stronger than a simple butt joint, and stronger than a miter, but still fairly weak in the big scheme of things.

Again, much will depend on how much racking force this table is exposed to. What's it for; where will it go? If it's a hall or sofa table, i.e. mainly decorative, any of these joints will likely be sufficiently strong. If it's a coffee table ... maybe not.

Lastly, will your legs be positioned all the way out to the end of the top? If so, you'll have a free span of some 57", which is getting pretty long for a top that's only 1-1/2" thick with no aprons below it to help hold it straight.

[cyberbum]

It's a table sitting behind our sofa, kind of like a coffee table (except we already have an ottoman in front of the sofa). So no one will be putting their feet up on it:P

Yeah there will be 57" long with no support, which I also thought would have a good chance of sagging. I am always able to shorten the length in that case, probably 40" would be the minimum.