i've tried now a few times to get this to stick to the concrete, but it doesn't. i've even roughed up the surface a bit.
using mortar mix.
is there something i can add to the mix that will help it stick? or should i use something else?
i like the mortar mix because it is smooth and sets up nice.
hope to do this again this week because the car that is usually in and out of the garage is gone and it can cure before getting driven over again.
songbird
Try using some Titebond III in your mix , and coat the area with some before you put the mix in place . Roughing it as you've done can help . Also , "grinding" the mix into the surface can help .
Terry Coombs wrote: ...
ok, tks, will give it a try. can't be any worse than what is there now. hate the idea of having to rip it all up again, but at least i have places i can use the scraps as fill. :)
songbird
Terry Coombs wrote: ...
will that give any flexibility? there is a slight crack in the slab and i'm hoping to have something a bit more flexible over it.
by slight i mean hairline...
i know there are rubber type additives but i'm not sure they'd work for mortar mix.
in the end if this doesn't work the next thing to do would be to get a grinder and take the whole sill down to give it the right slope. i'm not looking forwards to that extreme tho...
songbird
My first thought would be to use epoxy.
Etch the old concrete, dampen it and brush it with "bonding agent" which is basically titebond, and mix "bonding agent (titebond) as part of the water when you mix your concrete/mortar. I'd recommend using a "grout" mix over mortar, myself.
snipped-for-privacy@snyder.on.ca posted for all of us...
IMHO this is the best solution.
songbird wrote: ...
...
they didn't have Titebond III but another bonding agent. so i chipped out the whole sill this morning and then redid it with fresh mortar with the acrylic bonding agent added to it (about 2/3 bonding agent and
1/3 water) also used the bonding agent as described on the container to coat the surface before i put the mortar down (everything was kept damp as described).some of the previous rounds were sticking pretty well, but not in the area where it comes up (gets the most traffic). it is amazing what you can do with a hammer and a chisel. :) scraped the whole area clean down to previous concrete slab and then i made sure the area was roughed up by grinding it a bit with a coarse stone. the stone really didn't seem to do much but i figured it was better than nothing. swept off the dust, rinsed it off and then put down the new mix.
finished up just in time for a rain storm so damp cure is not a problem. after it passed and the sun is out i've put towels over the area and hosed 'em down. i'll do that every few hours until i go to sleep tonight.
my previous efforts were all done in the fall when the temperatures weren't the best too, so i'm sure that didn't help.
songbird
Have something to add? Share your thoughts — no account required.
Ask the community — no account required