3 or 4 to 1 portland, silica sand?

My first responce is, why would you want to make your own thinset?

Is there something special your doing that needs some custom mix or are you trying to save money?

In the end I guess it would be to save money, but I've torn out some tiles for a remodel and I think the thin-set was made by the guy, really dark grey and had the bond of 100 screws. Dark grey like plain portland and some fine sand. A million peices those came out in. I could'nt be sure, but it was glued w/ a 1/4 V notch over plywood and had been there about 20 years.

Probably was a plain thinset mixed with a latex additive instead of water.That was the thing to do over 20 years ago to make a thinset mortar sticky enough to adhere to plywood.Now,we have polymer modified thinset.Basically the latex is already in the bag.

For a superior bond to plywood,you can use Mapei's mortar called Kerabond and mix it with Mapei's liquid KeraLastic(in lieu of water).

Some stone masons still mix their own mortar to suit a particular application since there aren't too many choices for mason mix out there .But with the many varieties of tile mortar available,there really isn't a need to make your own.

Bradley

I think most quality thinsets are in the 1/ 1 or 1/2 range for cement to sand.

But, like the other guys said, I don't think it would be worth the effort unless you were setting huge flagstones that would require a huge amount of thinset.

thanks guys, I can check that one off the list...