Thread: Three legged table - Attaching legs

Hi Lance.
You have to make a box that sits accurately and bolts to your lathe bed. Scribe a line down the middle of the base board and add blocks that locate between the gap in the lathe bed with bolt holes drilled through. Make blocks that pulls the box down to the lathe bed. Then add the sides and guides. Its open at both ends and can be braced and have stops added for router travel once it in position. The width is determined by the leg/ column and the router. You could have a wider leg and a box that only suits a smaller router as well .

This one I made for reeding 4 legs. The reeded section was tapered so the box was made to suit the taper of the legs .
For dovetailing the box will be level with the lathe bed.

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Double check Mark out the divisions with pencil or texta before routing

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When I make larger tables like yours I like to add a tri steel strap under the legs attached to the column. They last better that way . Without them dovetails eventually break . Treat it well and it wont be a problem for 50 to 100 years though. Smaller wine tables don't need it . And on larger tables I like to mortise and tenon three or four leg designs like that as well. Even though traditionally they were DT . M&T is stronger and the only reason I do it is because of the machinery I have makes it easy.

Rob

If you make a box wider than your router and with a bed for the router that suits you could level the three sections for the column for the legs first. Possible by adjusting the depth of cut of the router and sweeping left and right by hand. Then add in and tape into position filler strips that center the router for the dovetails .

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Otherwise you have to scoop a radius into the ends of the legs to sit against the column.

This is a M&T 4 leg. Being mortised on the chisel mortiser . You can see the flat areas which can be put in for the DT method as well .
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Thanks a lot for that detailed explanation, Rob.

I did find some plans to mount a trim router on the tool-rest, but they didn't really seem very robust. Your example is right on the money. A significantly more rigid and controllable jig which will allow me to use my full-size router. Thanks for the tip of making it wider to allow levelling too.

I was contemplating your comments about joining the legs with MTs rather than dovetails. I have had some poor experiences with sliding dovetails breaking under strain. Perhaps they have been a poor choice for Tas Oak, but several times bitten, I'm a little shy now, so think I'll spring for mortice and tenons on this occasion instead.

When you refer to a "tri steel strap", are you talking about a strap which runs part way down the back of each leg, joined in the middle? Whilst we won't be doing dovetails on this occasion, it would be good to know for future reference.

I was talking to my son about this last night, and think we'll turn a separate hub into which the legs will mount, then mount it to the base of the column. He has put a lot of work into the table base thus far and would hate for him to mess it up at this stage.

I'll keep this thread updated on our progress.

Originally Posted by LanceC

When you refer to a "tri steel strap", are you talking about a strap which runs part way down the back of each leg, joined in the middle? Whilst we won't be doing dovetails on this occasion, it would be good to know for future reference.

I was talking to my son about this last night, and think we'll turn a separate hub into which the legs will mount, then mount it to the base of the column. He has put a lot of work into the table base thus far and would hate for him to mess it up at this stage.

Yes its sheet steel cut out to run up each leg from the center of the column. I used them on DT and specially M&T because M&T has no mechanical way of stopping the leg coming away from the column. Just the glue . Same as doweled on legs . Which I repaired heaps of over the years on tri leg dining tables . Doweled is the worst way of doing them I reckon. Specially when glued on with hide glue. I repaired heaps of broken 18th century original dovetailed dining and breakfast ( larger round ) tables as well and almost every time it was a table with no steel strap support.
The strap can be marked out and cut as one from a sheet of 1 to 1.5mm sheet steel but what I ended up having made was laser cut single pieces that I would place on the column and chisel the steel center out then weld the three or four together to become one . On a lot of those tables there was also a steel rod and nut sticking out the center of the column so the straps had a hole at the wide end for that as well . This is the only picture I have of part of what Im talking about .
The nut and rod and one of the straps. Its the positioning of the screws that hold the strap to the leg or leg to column join that determine how good it works. The low points have to be marked and the strap screwed down into them for each strap to be in tension for it to work well.
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With all that though if its just wine table size or round side table size, so a 300 to 600 diameter top on a column then no steel center rod was used , which was a way of bolting the X top plate to the column, and no steel Tri strap was used. A good joint well glued and clamped works pretty good.

I don't think Id be doing a separate hub . More of a fiddle and how do you join that to the rest. Just glue it? Doing a good job was all about marking out the piece well and holding it well . A lot of the time, to mortise them Id make a board up with two ends that the column sat in so I could clamp it and that would sit in the chisel mortiser. You would be mortising on the lathe in the same jig though which will be good.

The next problem is how to clamp the leg on well while gluing with M&T. Which is why a DT is a good idea . Not so involved.
I should have mentioned this first. I just realized . The clamping of legs to columns is the most important part for M&T that has to be worked out and it can be hard using just timber because it has to be 100% spot on with the clamping direction and the strength of the jig.
I can cut and weld steel up and an hour or two making jigs was part of the job on making an expensive table.

For this job I made two of these that took the shape of the leg and stopped it sliding by holding the foot . They hooked on around the feet. The timber screwed on gave the 2 direction 90 degree ( How to correctly describe that ?) flat spot to the join for perfect clamping . One clamp would hold two jigs to the opposing legs .
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So you need to figure out the clamping of the leg first. You can cut scrap sheet wood to take the leg to hook around the foot and apply the correct angles to the joint for a one off use one leg at a time . Like chip board of MDF. You need to be careful with clamp pressure though. Making one from glued up solid cheap pine would be a bit better. Or if the leg has no slope at the top you have no problems because it will take clamps . The leg in your picture is sloped though at the top so needs a jig.

Doing a similar small table soon.
Some good suggestions here - thanks all !
I was thinking when the column is finished, I would tape some sanding paper to the column and shape the edge of the legs that way....
Is there a reason simple dowels between the leg and column are unsuitable for fixing ?
cheers
phil

Dowels are not unsuitable . They are just the most likely to need repairing if mistreated or not glued up right . Glue these days is better than the hide glue type I used to have come in for repair all the time as well .