Mixing thinset - Page 2 - DIY Chatroom

simonb · 07-03-2008, 06:08 PM

The bag tells me use 5.68L of water to 50lbs of mix. SO if my math is correct, I can devide both sides with 5.68 which gives me the results 1L of water to 8.8lbs of mix.

Of course i can devide this by 2 and make a smaller batch right?

angus242 · 07-03-2008, 06:26 PM

Quote:

Originally Posted by simonb

2 layers of plywood staggered, second layer nice side up

You realize the superseal directions say for this application to "use
unmodified thinset with the recommended amount of liquid latex additive."

just keep dividing by 2 to get your mixture. Thinset under the superseal will be a bit thinner than normal.

simonb · 07-03-2008, 06:31 PM

I know what you mean. Its very hard to find information on their site and most of the links arent there, you have to google to get links to their site.

Here is a direct link to their installation pdf http://www.superseal.ca/NewPDFs/Tile_Subfloor.pdf

If you look at the THINSET area;

THINSET'S - On concrete substrates you can use unmodifed thinset or with or without a liquild latex additive. For all other applications,use unmodified thinset with the recommended amount of

liquid latex additive.You can use the premixed modified thinset but drying time is considerably longer.

The last line says I can use premixed, but it wont dry as fast and i assume i cant install tile right away like the instructions say. But in my case im only installing at least 24 hours after.

Is this correct?

HomeDepot23 · 07-03-2008, 08:53 PM

Pre-mixed can take an age to set. Think the pros will agree with me when I say put down the pre-mixed and back away.

Bud Cline · 07-03-2008, 08:59 PM

Simon you must be an engineer of some kind! Most people that come to these forums obsessing with the proper way to mix thinset are engineers of some description.

Put a single quart of water in a bucket. Slowly add the powder as you mix. When you get to creamy peanut butter consistency stop adding powder and mix thoroughly. Wait ten minutes and mix thoroughly one more time. Now the thinset is ready to use. Don't measure anything other than the first quart of water.

If you decide THAT batch was too big or too small then do the next one different and adjust up or down from your first experience.

Thinset is usually a very forgiving thing and shouldn't be giving anyone a heart attack.

simonb · 07-03-2008, 09:09 PM

There is nothing wrong with premix, just that it takes longer to set, no big deal, even the rep at the 1-866 number said you just have to wait a day.

Bud cline, i know i over analyze this stuff at times, but in my defence, measure once cut twice... no wait, measure twice cut once

As for the mud, its nice and thick. When i use my notched trowel the square notches it leaves dont fall. And at the same time its easy to spread, almost like drywall mud.

I was wondering is the mud supose to just stick to the thin cloth under the underlayment or does it go through?

Oh by the way, im about 80% done, just waiting 10 minutes to mix again

HomeDepot23 · 07-03-2008, 09:13 PM

"even the rep said wait a day" Er, try 3-6 in many cases. I know, I get the complaints!!!

simonb · 07-03-2008, 09:27 PM

Quote:

Originally Posted by HomeDepot23

"even the rep said wait a day" Er, try 3-6 in many cases. I know, I get the complaints!!!

Hes not a rep, hes the technical support for superseal.

Bud Cline · 07-03-2008, 09:56 PM

The thinset should readily saturate the cloth. You should be able to see thru the plastic (sorta) and you should be seeing it turn dark as it becomes saturated. I think you are mixing the thinset way too thick. It doesn't hurt in this case for the peaks to sag a little.

You do what you want but if I were you I would stay away from any and all of the premixed products. They have proven to be trouble. we see many complaints and nightmares on these boards coming from victims of the premixes.

Are you rolling the mat or doing something to thin and evenly

spread the thinset under the mat after you drop it?

MinConst · 07-03-2008, 11:05 PM

I've been through 2 or 3 drills mixing mud. Bought Heavy duty 1/2" one at Harbor freight for 20 bucks and it works good. When it burns up I'll get another.

simonb · 07-03-2008, 11:09 PM

Once i put the superseal on the thinset, i start in the middle and use a trowel to push the mat into the thinset. Once im done with that i use a little end of a 2x4 and do it all over again. I pushed hard enough to start driping swet, so im sure i pushed it in there good.

Now that im done your making me paranoid lol. Im prety sure that i installed it correctly. I can see why you would want the thinset a little more watery now. Whats the worst that can happen at this point? What if there are a couple small 1 inch areas that arent 100% darker then others?

Is there a way to see if i did all this correctly by saturday morning?

Quote:

Originally Posted by Bud Cline

The thinset should readily saturate the cloth. You should be able to see thru the plastic (sorta) and you should be seeing it turn dark as it becomes saturated. I think you are mixing the thinset way too thick. It doesn't hurt in this case for the peaks to sag a little.

You do what you want but if I were you I would stay away from any and all of the premixed products. They have proven to be trouble. we see many complaints and nightmares on these boards coming from victims of the premixes.

Are you rolling the mat or doing something to thin and evenly

spread the thinset under the mat after you drop it?

Bud Cline · 07-03-2008, 11:49 PM

You can tell right now if it's done correctly. If the thinset hasn't saturated the fabric everywhere the product will not bond.

I am a certified inspector for ceramic and stone tile installations. Claims come in about DITRA from time to time. Each and every time someone has alleged the DITRA has failed an invasive inspection of the circumstances shows that the DITRA was not installed properly because the thinset was too thick and the fabric did not get saturated.

simonb · 07-04-2008, 10:03 AM

Well the only problem i think i ran into is my thinset. I followed the directions on the bag and now im finding out i should of went a little thinner (notched edge slope a little). Im including photos for people that have done subfloor with ditra or superseal to give me opinions. I rather have to pull up and install new now then when the tiles are in right!

http://brazco.com/1.jpg
http://brazco.com/2.jpg
http://brazco.com/3.jpg

simonb · 07-04-2008, 01:24 PM

Ok, im pulling up the superseal and scraping the thinset off, everything is coming off fairly easy since the thinset isnt very dry yet.

Now to do it properly! My questions.

First off, i had a couple smaller peices of superseal cut, should i avoid smaller strips this round? what is the minimum size that i should have?
Im going to try to use a better modified thinset or mix my own. What are the recomendations of products? My store choices are HD, home hardware, and rona. Im sure they carry the same in these stores in other areas. I was thinking kerabond dry-set with its liquid aditive like angus suggested. Does this dry faster?
As for the thickness of the thinset, i was going to mix small batchs like I did before, but after the first mix i was going to use a small hand trowel and scrap peice of wood and test it out to see if the thinset notches will start to sag. Should i test after the first mix or after the 10 minutes? Also should it start sagging a few seconds after i notch it?
The plywood is now a little wet from the thinset, should i wait till its completly dry before doing anything? Its also a little gray, should this be ok or will i need to lightly sand it or anything?

Thanks for the help guys, ill take my time this second time around

angus242 · 07-04-2008, 01:38 PM

First off, i hade a couple smaller peices of superseal cut, should i avoid smaller strips this round? what is the minimum size that i should have?
Try to keep the amount of seams to a minimum

Im going to try to use a better modified thinset or mix my own. What are the recomendations of products? My store choices are HD, home hardware, and rona. Im sure they carry the same in these stores in other areas. I was thinking kerabond dry-set with its liquid aditive like angus suggested. Does this dry faster?
Kerabond + Keralastic is perhaps the best thinset for this application.

As for the thickness of the thinset, i was going to mix small batchs like I did before, but after the first mix i was going to use a small hand trowel and scrap peice of wood and test it out to see if the thinset notches will start to sag. Should i test after the first mix or after the 10 minutes? Also should it start sagging a few secondsafter i notch it?
Mixing the thinset a bit more watery than normal will help it permeate into the superseal fabric better. Not slushy but not thick either. You've been given plenty of advice on this step. It's not rocket science. You need to use your judgment on this step.

The plywood is now a little wet from the thinset, should i wait till its completly dry before doing anything?
This will be just fine. I typically mist plywood with a spray bottle before laying thinset anyway.