Loose push fit fitting

[Jackrae]

If you want rigidity I'd suggest you avoid soldering the joints as the heat of the soldering will anneal the copper and soften it. Gluing end-feed fittings is probably your best bet.

 

[Nozzle]

Just learn to solder, it's very easy to do, you just need to invest in a blow torch, length of plumbing solder and a tub of flux. The key to it is to be clean and grease free before you even start slapping flux on. The flux does some cleaning while it's hot, but it won't get through thick oxidation. Soldering pipes together is a piece of pish. And with more practice you can make joints look nice too.

Nozzle

 

[mcmoby69]

If you want rigidity I'd suggest you avoid soldering the joints as the heat of the soldering will anneal the copper and soften it. Gluing end-feed fittings is probably your best bet.

you shouldn't be heating capillary fittings to anywhere near the annealing temperature when soldering.

the solder won't run or stick for a start, plus you'll end up with discoloured copper, which , if its furniture won't look too pretty.

 

[Nozzle]

And speaking of discoloured copper - you'll need to apply some laquer or dedicated coating to shiney copper if you want to keep it shiney

Nozzle

 

[Alec_t]

What size is this table and is it likely to be subjected to kids or heavy loads? 22mm copper tube of any significant length may need an internal dowel for increased rigidity.

 

[Dan Robinson]

I assume it will be filled with some kind of ballast to strengthen the tube from bending.

Sand for example?

 

[Jackrae]

Sand ballast won't stop it bending, merely stop it kinking if it does bend. That's why sand is used as a bending medium.
Providing lengths undergoing bending forces are reasonably short, the strength of a soldered copper tube space-frame is quite surprising.

 

[Dan Robinson]

A good point well made.