thinset modified or unmodifed and where

I just saw your tropic and make me wonder now on my bathroom job. I said Iwere planning to use Versabond from HD. I believe their is a modified thin set. My project is Hardie bd over plywood aHardie bd to tile.
So if modified thinset take a three month to set for 12x12 tile, then I can not grout till approx 3 months? What happen under the Hardie board and plywood? Will that take that long to set too? Wouldn't that be a problem to set tile while the thin set is still jelly like under the cement board?
Maybe I need a unmodified thin set under my cement board and a modifed thin set on top of cement board?
Confuse yes!

You are really over thinking it again. You can use either modified or unmodified under the hardi, they allow either underneath. You can then use the Versabond to set set your tile and to tape the seams as you set your tile.

If you get your supplies only from HD, since the only unmodified they carry is Custom Blend, a cost effective alternative would be Multiset, which is a lightly modifed thinset.

The discussion about modifed taking 3 months to cure was when used over a particular type of underlayment which is not part of your installation and nothing you need to worry about. The thread was a 4 year old thread brought to the surface for no reason whatsoever. Let's all pretend it never happened.

Actually, to ensure your thinset cures properly, you'll want to wipe the Hardi down with a wet sponge before you comb any thinset on it. It's very thirsty and likes to suck moisture out of thinset. It will also get rid of dust on the surface that could be a bond breaker.

How come you are not done yet?

Tileplayer,

If you will follow Bljack's instruction you will be fine. You ARE overthinking this whole thing. I'll bet you are an engineer of some kind.

No thinset takes three months to dry. It won't happen. All thinsets in your case will easily dry overnight - twenty-four hours at the longest. I'm not sure which thread you are referring to but I am sure you are taking statements out of context then trying to mold them to your job, and that don't work.

If you are shopping at HD then quit trying to compare the products and trying to figure out the recipes. Just use the Versabond for everything and be done with those decisions - you'll be just fine.

Carry on.