It would be slicker than snake snot on a tin roof.
Do tell more. I still find myself thinking the pressure of a “snug” fit would work, but it appears I’m missing something.
The problem is that most of the fastening methods we’ve been discussing - bolts, screws, paired locknuts - work because of friction - they tighten to the point where surfaces are pressed together sufficiently hard that they are experiencing friction to a level that overcomes any tendency for the joint to loosen.
But with materials entirely frictionless by definition, there is no way to jam surfaces together like that - they will always slide, instead of jamming.
But that just highlights the problems with the notion of entirely frictionless materials - if there’s no friction, there’s nothing (really) preventing you from screwing an M6 bolt into an M5 nut, or forcing a square peg into a round hole - at first glance, that might seem silly - because those involve a case of physical interference - but it’s not silly - friction is what hinders things being put into holes ever so slightly too small for them - without that, where is the boundary condition that prevents things being put into holes not only slightly too small, but far too small?
I think it’d be binary. Either it fits easy or not at all.
I guess, although that doesn’t really mesh with our existing knowledge of materials, but then that’s what generally happens when you posit some material that violates nature.
Wait. Why would you think that? Are you drawing some inference about lack of inter-molecular forces within the material from the lack of friction?
Because surface friction isn’t the only thing preventing you from sliding a 6mm rod into a 5mm hole–there’s also the stiffness of the material itself. (If a material had zero stiffness, it would collapse under its own weight which would be truly silly.)
Suppose you have a block of unobtanium, which has zero surface friction, but does have some stiffness. A 4mm hole is drilled completely through the block. You try to force a 5mm dowel into the hole. To fit the dowel, the unobtanium around the hole must stretch. Stretching the material requires energy. That energy must come from somewhere, and it does–it comes from the force required to ram the dowel into the hole.
So what would happen is that you’d need a press to force the dowel into the hole. However, if you forced if in only halfway, the material around the bottom edge of the dowel would squeeze the dowel back out of the hole, and since there’s no friction, you’d have to keep a constant force on the dowel to keep it in place. Once the dowel was fully through the hole, no more energy would be required to deform the material, and the lack of friction means that you can zip the dowel farther through the material without exerting any force.
I think I’ve figured this out. Apparently, increasing pressure between two objects pressed together works only because increased pressure merely means increased friction along the mating surface. What made this clear to me was the idea of pressing two books together with the boundary plane oriented vertically. With insufficient pressure between the books, gravity will win over the week friction along the boundary and the books will tumble. With enough pressure, the friction will beat gravity and the books will stay “stuck” together, so long as the mutual pressure exists.
And so books with frictionless jackets would always lose out to gravity, since even the greatest pressure imaginable would induce no friction between the two.
And I’ll second Tao’s’ binary idea. You just aren’t gonna shove a 2-inch-square page in a quarter-inch hole, no matter how much you lube it. I think. . . .
How are you going to be able to pick them up?
No friction, remember?
(anyone old enough to recall the STP commercial with the screwdriver?)
I think you missed the part where **msmith537 **said this:
D’oh!
That’s what she said.
Stop. If there’s zero friction, the drill bit would just slip and slide and never bite into the material. QED
Not if you use lots of screws. Trust me. 
Actually, I see no reason why bolts would not work: a bolt on one side, threaded through two pieces of frictionless stuff, and a nut on the other side attached to the bolt, would certainly keep those two pieces of wood together. If there were only one bolt, the frictionless wood would slip and slide around the bolt’s axis, though there would be no danger of unscrewing the nut.
What about duct tape? 
Yes, and rivets would also work, but the problem, as I said in a post above, is that you could not drill a hole in said table. Now, if you formed the table with holes in it, then you’d have solved that problem.
Hey, here’s another problem. Call it a dining table. As soon as you pull up to it to have your meal, and bump into it, it will go sliding. The folks around the table will have to belly up right to the edge to keep it from sliding all around. I hate when that happens.
Doh! :smack:
Don’t feel bad…apparently you’re not alone!
Yes, it’s true that the ability of the materials to deform would be the factor limiting fit - as it is with normal materials - except that with normal materials, the forces arising from the tight fit very often cause the surfaces of the materials to jam together - and this is what limits the fit.
So yes, of course there would still be a limit, as you say, but (in the frictionfree case) for any fastener that can be made to fit in the hole, it will slip out as easily as any other fastener - regardless how tight, because surfaces jamming together is ruled out by definition.
Unless, as I suggest, you use rivets. Several could hold frictionless parts close together, and placed strategically, could render it stable.
Sure - rivets, ordinary bolts, screws through into normal material, etc - would all work.
You could theoretically screw one screw at right angles into another screw — same principle as some of those IKEA-type U Can Bild It Urself table kits. (I’ve seen some with a twisty-locky thing like a cylinder that spins and catches on a bolt coming in from a different angle.)