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How to overlay without trowel marks?

4 replies [Last post]
New Again

Ok, just finished a high end job using Ardex SD-M.  This product is not good if you want a floor completely clean of trowel marks and even pinholes.  The customer service in Pensilvania and locally in Dallas is the usual concrete trash level - passing the ball, not returning calls, contradicting claims, etc. The date printed on the bags is supposedly not the date of production... so the product is not  6 months past expiration but "it's fine".  Bags have contradicting instructions printed in different languages. Ok, that passes for "professional", fair enough, we've seen worst and we've made it work.

That being said for the next job I intend to use Ardex again - because I can not dig out info on any other microtoppoing that will not produce trowel marks. I intent to use Ardex PCT, which is a self leveling polishable material.  The documentation does say that it can be feather edged but I guess I have to find out myself.  And the material produces two superficial layers - a grey one and a white one which are removed during the polishing process.

 

Questions:

1. What other microtopping overlay can I use if I want to have zero trowel marks AND be able to feather edge?
2. If I have to use ARDEX PCT do I really have to grind off the top two layers or I can densify them, seal, wax, done?

Please respond only if you have experience with the products/techniques you suggest. "Should work" is not good enough.

 

My last resort is a cheap tinted acrylic sealer that will hide all microtopping imperfections and get a few coats of wax on top.  Not the best and not to my liking. I hope for a better suggestion.  Thanks in advance.

 

sonny.u
No trowel marks

Theirs a system by Concrete Solutions, "spray top"... Polymer + powder + their sprayer = even thin cement coating with no trowel marks. But, you can use any fine micro and polymer system, just put down prime coat first of pure polymer, then mix it up real soupy like a thick paint, strain it, then get a pressure pot and a sprayer from Ben Ron... And save your self some dough. ..let me know if you are interested and I'll send you the link to their page. It's pretty cool.. Most overlay sprayer, come out all textured like a drywall hopper.. Not this.
Second way but not so perfect at first, and once on a while you get one or 2 little boo-boos is same soupy paint mix of overlay bit with a magic trowel on a stick and where shoe Spikes... We've been able to lay em down prety nice, 2 coats... First one some time has to be sanded hear and their.
The 3rd in now about is the arapido sprayer... But I can't get my hands on one,.. To do any testing.

New Again
Sonny,   Thank you so much

Sonny,

 

Thank you so much for the reply!

 

I had found Benron and mean to call them to see about their prices.  Thank you for the tips for the polymer as primer, straining, and the difference between Benron's sprayer and any other.

 

Mixing a product soupier than the documentation says seemed good to me until I used more water to make Ardex SD-M runnier.  The stuff is not meant to be overwatered.  So making it runnier did not get rid of trowel marks - we sanded them flat but you can still see them.

 

Thank you again, I will check out Benron's prices.

sonny.u
Reply

No problem! This forum is straight gold. But only works if people reply. It used to be their was alot more activity. And with are trade theirs so many sales people, with no real life experience... We have to help out where we can, theirs so many little details that makes the biggest difference in the finish. Like the whole priming before you start your topping ... Other wise as soon as you put that overlay down the substrate sucks the moisture right out of your mix making it dry faster, harder to flow and pin holes. With the whole magic trowel soupy mix, we got that down prety good, pour a puddle of super wet overlay and pull the puddle around making sure to clean it off now and then so it don't leave clumps and boogers (except where the base mold goes at the bottom of the wall, it always builds up right their a hit here and their). Also, Theirs some spray top video stuff out their on you tube, that you'll be able to get an idea what you van do with the Ben Ron Colt Crete sprayer.

New Again
Sonny,   I talked to Benron.

Sonny,

 

I talked to Benron.  Apparently the guy travels a lot and their phone doesn't have a mailbox setup. Anyway - I asked him what is the cheapest spray rig they have for cementitious microtopping.  He said aboyut $2,000 with the gun included.  But it needs a compressor that does not come with it.

 

A local guy that used to make his own overlays back in the day when they were not sold commercially told me that for spraying microtopping I can use a Graco sprayer.  He's checking on the model.  He said that he has seen guys spray microtopping over formica (priming with polymer first) and it stuck just fine.  I don't want to do that but I'm interested in the Graco sprayer.

 

Thank you for your advice!