Aaron FIsher wrote:
On Fri, 08 Apr 2011 13:03:57 -0700, JIMMIE wrote:
Superglue should hold tiles pretty good.

I've never had success with cyanoacrylates on (a) porous surfaces, and
(b) large surfaces.

The problem with cyanacrolates (e.g., superglue) is they the glue
itself is extremely weak. So, while the molecular bonding is
fantastic, you really want a single molecule layer thick of the
stuff, no more, no less.

That's really hard to do on rough cracked chipped porous surfaces
like a clay tile, even a recently broken clay tile. So, from 'my'
experience, superglue would be one of the worst possible choices for
clay tile.

Besides, we're talking a LOT of (what turns out to be expensive) super
glue! Even if it did work (which I really doubt it would).

But, not to sound condescending, I 'do' welcome the suggestions. I'm
particularly motivated now that you guys tell me roofers habitually
glue roofing tiles (I hadn't expected that).

Is there an epoxy that can set while I'm on the roof holding the tiles
(two minutes or so)?

the faster epoxy sets, the weaker it is, in general.

if you can remove them, glue them in a jig, and heat them gently, then
replace, they'd be stronger. you could also laminate them on the down side
with some fiberglass mat wetted with epoxy for reinforcement.