Weber 310 Primer problem?

chowyunfatt

New Member
Hi, first time posting :)

I've just rendered a house, my house actually with OCR, my first time using this as I normally do S&C.
Used Weber rend aid, meshed and textured for key. Then Weber OCR 20mm thick and then scraped flat with I bar, pressed with float to form a flat semi smooth, textured finish ready for primer.

As you can see from the two pictures the finish looks like a good key as some I've seen put the primer on to smooth walls. My question is how easy does the 310 primer scrape off the OCR from the people that have used OCR, the primer and TF finish? The problem I have or think I have is it seams easy to scrape off easily. (Ive included 2 videos of examples)

Looking at the video Ive included the main walls seem like a really good bond, I cant really scratch into it or scrape it off so I think this should be OK and not create any problems down the line, but I think the main problem is the reveals, it scrapes off easy IMO.
I dont want to start top coating the TF if there is a problem with the primer, am I being paranoid or does it look like it comes off easy? Will the weather, conditions and time some how blow or peel the TF off stuck to this primer?

Any help would be very much appreciated.

Finish
https://drive.google.com/file/d/1MjbmmGsRvuUhwYRe28nP8aF5K4GjLvp8nw/view?usp=sharing

Primed
https://drive.google.com/file/d/1JblaCLbk4Ex-JmkxcPVCFLqfaYEqpskHnA/view?usp=sharing

Main wall primed, very hard to scratch into or scrape off
https://drive.google.com/file/d/1AAqxQ0Kx2TabuRBfkFDTdaSenzqaNUaXMQ/view?usp=sharing
https://www.dropbox.com/s/j555xgb296cm56t/VID_20170903_102422195.mp4?dl=0

Reveals, easy to scratch off
https://drive.google.com/file/d/1OP4-itEPSo-ZMKhNdDtPyU9m_rTfx58vNA/view?usp=sharing
https://www.dropbox.com/s/g4lpr87z5ei7qjs/VID_20170903_102507794.mp4?dl=0
 
Last edited:
Hi, first time posting :)

I've just rendered a house, my house actually with OCR, my first time using this as I normally do S&C.
Used Weber rend aid, meshed and textured for key. Then Weber OCR 20mm thick and then scraped flat with I bar, pressed with float to form a flat semi smooth, textured finish ready for primer.

As you can see from the two pictures the finish looks like a good key as some I've seen put the primer on to smooth walls. My question is how easy does the 310 primer scrape off the OCR from the people that have used OCR, the primer and TF finish? The problem I have or think I have is it seams easy to scrape off easily. (Ive included 2 videos of examples)

Looking at the video Ive included the main walls seem like a really good bond, I cant really scratch into it or scrape it off so I think this should be OK and not create any problems down the line, but I think the main problem is the reveals, it scrapes off easy IMO.
I dont want to start top coating the TF if there is a problem with the primer, am I being paranoid or does it look like it comes off easy? Will the weather, conditions and time some how blow or peel the TF off stuck to this primer?

Any help would be very much appreciated.

Finish
https://drive.google.com/file/d/1MjbmmGsRvuUhwYRe28nP8aF5K4GjLvp8nw/view?usp=sharing

Primed
https://drive.google.com/file/d/1JblaCLbk4Ex-JmkxcPVCFLqfaYEqpskHnA/view?usp=sharing

Main wall primed, very hard to scratch into or scrape off
https://drive.google.com/file/d/1AAqxQ0Kx2TabuRBfkFDTdaSenzqaNUaXMQ/view?usp=sharing
https://www.dropbox.com/s/j555xgb296cm56t/VID_20170903_102422195.mp4?dl=0

Reveals, easy to scratch off
https://drive.google.com/file/d/1OP4-itEPSo-ZMKhNdDtPyU9m_rTfx58vNA/view?usp=sharing
https://www.dropbox.com/s/g4lpr87z5ei7qjs/VID_20170903_102507794.mp4?dl=0
Hi , no ones answered you yet , I'd like to ask though why have you started trying to scrape it off ? And what are you putting on top ?
 
Hi, Im putting on Weber TF. I was just checking that the primer is well sealed, stuck. The TF is only stuck to the primer so if there are problems with the primer it doesn't matter how well the TF is stuck if the primer can be easily removed from the OCR.

I know you wouldn't scrape at it normally but it just seems that it's not stuck well enough? thats why I was just wondering if other people who use this know how well it actually sticks.
Having never used it before I'm not sure what problems could occur in the future, frost, rain, heat, sun and so on.

The only reference I have is if you're painting a wall and dilute the paint it gets a good key and soaks in to the plaster so it's almost impossible to scratch off, this stuff can't be watered down and it seems like it sits on the surface of the ocr.

Maybe its the OCR? how strong is that stuff supposed to be, can that be scratched into easily thus removing the primer.
 
Dusty surface? Sometimes when rubbing up on the dry side you get a weak surface. Rub your hands over the surface and if its solid no dust on your fingers.
 
Did you had any salt coming through on the substrate, before applying the render? I have to admit that's unusual.
 
i would spray the dusty areas with water as i guess that the render has dried to quickly and the cement has not reached full strength.

we leave the primer to cure for 1 week before we apply the acrylic finish. i like the 1.5 acrylic finish best.
 
Dusty surface? Sometimes when rubbing up on the dry side you get a weak surface. Rub your hands over the surface and if its solid no dust on your fingers.
i would spray the dusty areas with water as i guess that the render has dried to quickly and the cement has not reached full strength.

we leave the primer to cure for 1 week before we apply the acrylic finish. i like the 1.5 acrylic finish best.

I think this might be it, one wall is dustier than the others too. It must of dried quicker for some reason but it had the same rend aid and a damp down the same as the others. Maybe I didnt press it in enough and with a more open grain that has made it dry quicker? like the reveals?

So I suppose my next question is if it is a bit weaker will it be ok? you can't scratch the ocr off unless you apply pressure and dig into it a bit. I've applied the primer in a small spot on this wall to test the last couple of days and it seems well stuck like in the video I posted but if I dig in the OCR does seam a bit softer than normal. If I do a couple of primer coats and leave a good few days this should basically stick and have no way of coming off in the future? The primer also seemed to soak in a lot more too so I assume this is because of the grain or softer material?

Im just a bit paranoid now, I look at it and thick there is no way that primer is coming off but then I start doubting myself and think of scenarios where the OCr could flake or crumble underneath or something.

Thanks again guys.
 
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