Hi Payal
I would suggest filling the legs with papier mache pulp - when it sets, the legs should be quite solid, but you need to make sure the pulp gets packed in right up to the table top. That should hopefully solve the problem!

Zyggy

It's going to take a long time for the pulp to dry inside the tubes, and the basic Rule of Mold is that if it isn't dry in three days or so, it's going to start developing mold.

Those cardboard tubes are really too thin and weak to bear much weight, even when dry, in my opinion.  Would it be possible to cover them with corrugated cardboard and then PM over that?

I would use cardboard from a large box or something, and arrange your "pattern" (measurements) on the cardboard so the corrugations of the cardboard run vertically, and there are no box folds involved (they will make it weaker).

Corrugated cardboard's strength is in the interior corrugations.  You've tried to fold cardboard in the past and discovered that it is easy to roll it with the corrugations, and almost impossible to roll against them.

If removing the cardboard tubes would be too difficult at the point you've reached, wrapping them with one or two wraps of corrugated cardboard will strengthen them.

But the strongest cardboard legs are going to be made from a solid spiral of cardboard (have you ever poked someone in the stomach with a rolled up magazine?) started small, you keep rolling until the leg is the thickness that looks right for the table.  Then tape it securely and apply PM around it.

When attaching the legs to the table, overlapping it is the way to go.  With materials like this, the weakest joints are butted end-to-end, with the only connection being where they meet.  That is always the most likely place to break if someone runs into the table.

But if you have to do that for the design of your table, gluing the whole end of that solid cardboard spiral will give you more contact than just gluing a narrow edge.

Ideally, the leg will attach to the table in more than one place, like the solid end to the underside of the table, PLUS where the top side of the leg touches the underside of the table apron (that might not be the right word.

Sue

Zyggy, one thing you just made me think of is, what about making legs (or other things), using wire mesh as a retainer (like rolling it up and wrapping it with wire to hold it firmly, THEN cramming it with pulp?  You could see through the wire if you're missing any spots, and tamp it down with a wooden dowel or something.  And the mesh would expose the pulp to air for faster drying.

Hmmm......  seems like this needs a trial, when I can work it into my schedule.

Sue

You're probably well on with this project now and I am coming in a bit late.  Another way to strengthen cardboard tubes is to take a second tube.  Squeeze it to create a waist.  It will look like a figure of eight in cross section.  Force it inside the original tube.  It will be very much stronger.
DavidO

Although I've never heard of that technique before, I think (?) he means to crease it inward down it's length,  then do the same on the opposite side.  Looking in the open end, it would (roughly) look like an O with a v top and bottom.  The Vs reduce the diameter of the tube so you can force it inside another tube.
             / v \
            |      |
             \  ^ /
Sue

PVA glue is probably more resistant to moisture than the organic types.

Sue