Thread: Coffee Table - Advice Required

There's a few choices, spline running along the mitre's lenght or multiple splines running across the mitre. Use some aluminum as the splines across the mitre as a modern contrast you'll need to use polyU glue though.
You could use box joints or even dovetails... Ah the possibilities!

Mike,

The problem with mitered joints is they don't tend to be as strong as other joints. So you see them mainly on decorative things (mirrors, frames, etc).

If you're really after the miter look, you can try a spline. Or you can glue an edge piece with a miter and use a more sturdy joint for the body. You'll still probably need to reinforce the joint with some diagonal braces.

If you're relatively new to woodworking, I'd suggest you avoid the miter. It can be very fiddly to get it right, even with good equipment. Small gaps are obvious. And for a coffee table, it's just not very strong.

Most coffee tables have four legs, a frame connecting the legs, and a top that 'sits' on that. It's a good way to get strength and stability, particularly if you use mortise and tenon (or domino, or floating tenon) joints between leg and rail. There's lots of room for design innovation within that framework, and a quick search of the forum will show a lot of great designs for tables.

If you're set on having half a box (two sides and a top) you will need some serious reinforcing whatever joint you use. Metal brackets, diagonal bracing, etc. And be prepared to throw it out after a few years.

Tex

hi Mike - if you haven’t been welcomed to the forum yet - WELCOME! And welcome again, from an old Coburg’er.

To your issue - if you have even a basic drawing or design of the finished product you wish to achieve, that would be a help - if I am understanding your idea correctly, you wish to make a box with a top, bottom and two sides. The issues as I perceive with this design, are to do with the amount of pressure that’s likely to be placed on the piece through normal use..... AND what may happen when a couple of people decide there aren’t enough chairs in the room and decide to sit on it or worse, stand on it to reach something high. I believe that mitred material 19mm thick would become loose and eventually fail due to the lateral forces applied. Even if splined, the potential for failure is pretty high as the amount of ‘bite’ the spline offers is still small compared to what it needs to do.

As mentioned, there are measures you can take to strengthen it, but I believe over even a short time, joints would open and eventually fail, diminishing your joy at having made it. Also as mentioned, mitres are fiddly - I have a $1200 ELU compound mitre saw and have rarely been able to get a perfect mitre - on the other hand, my $35 hand mitre saw does produce acceptable mitres, though neither of these devices will cut that way you need them to - you need to be able to very accurately cross-cut your material at 45 degrees. A fairly easy task on a middle range table or panel saw, but a real challenge on anything else, I feel.

By 'box holder' do you mean a device for securely holding mitred joints together while they are nailed or glued? If so, I doubt this will be sufficient for your project unless you used several of them at once......

The last thing I want to do is rain on your parade - the idea has merit and is certainly achievable though perhaps not best done in the manner or with the material suggested and almost certainly not without serious bracing. One thing that could help is to make a funky outer-perimeter, also from flooring but not mitred – it would run perpendicular to the main surfaces….. bit hard to explain but if interested I would do a (poor) drawing to illustrate.

Of course, serious metal angle bracing could also be used but even so, without substantial fixings, would still allow movement due to leverage. As you don’t want to see any nails etc. screws and nuts are out, unless you could include them as a feature in your design.

Anyway, the bloody cat just scratched me so I guess it’s dinner time for one of us anyway. Apologies if any of my rantings are too vague

Above all - have fun!!!

G'day fellas,

Thanks for your replies, I'm getting a strong indication that I need to look at another method of getting this thing going! As requested I have made a very crap pic in paint, a side view, with casters on the bottom.

I certainly don't have top of the range stuff, but for my previous projects (current coffee table, book shelf etc) I've used a 210mm sliding compound, with small teeth for pine and have been very happy with the results (granted it is cheap and nasty).

I'm almost thinking now that, like rustic furniture recycled furntiutre, it's not that bad having nail holes etc showing... maybe I'll go a little more straight forward?

Also, I have a recycled timber dining table (a real beauty out of ashwood) and it has like a dark black 'filler', in gaps and scratches etc. Looks great! Do you know what this substance is?

Thanks again,

Mike

PS. Thanks for advice Steve, not vague at all. My feline in an obscure corner of the laundry, and SWMBO promised me she was house broken! Nothing a swift kick up the ass won;t fix!

Still could do box joints(stronger than a mitre and easier), but as the others say 19mm stock dont give much strength used like that... you could double it to 38mm to give nice chunky joints.

Cheers Harry,

Erm... what's a box joint? Any idea about the black stuff?

Cheers,

Mike

Box joint: layman's description...
put your left hand in front of you with fingers spread wide, now put each finger of your right hand between the fingers of your left hand meshing fingers together(palms facing each other)... chop off the excess of the fingers hanging out flush with the back of each hand so now your hands form a 90 degree right angle... you now have a box joint!

Sort of like a dovetail joint except the tails and pins are cut square instead of triangle shaped(look like teeth).
Generally using this joint in your situation the fingers/teeth of the box joint would be cut to the same dimension as the thickness of the wood... 19mm stock use 19mm fingers/teeth, 38mm stock use 38mm etc etc, but you could have 10mm or 100mm fingers/teeth if you want!

Black stuff could be just wood filler tinted black with black oxide powder.