Wednesday, March 12, 2014

Poly Finish On Stair Treads Scratches Very Easily



I purchased a jug of expensive water based polyurethane from Richilieu (about $125) that contractors generally would use (from bad experience I wanted to avoid the local do it yourself orange box store brands). The problem I continue to have is surface scratches. It seems that I can put surface scratches on the poly just by moving my socks on the steps...I can even make a surface scratch with my fingernail.
I'm wondering if it's normal for poly to scratch this easily? It's not getting through to the wood, and steel wool and recoating will cover it...but it seems rather pointless as it just takes walking on them to cause the light scuffs and scratches. They're only visible with a good light on them, but I'm wondering if this is unusal or not? The staircase turned out beautiful, but if this isn't normal I want to tackle it again before i say it's 100%.
PS - I left loads of time for drying, btw. I also tried a few stairs with light coats and a few heavier. I find the heavier show the scratches much more, but regardless they all scratch very easily.

I'm not sure about the product you purchased, but from what I know of most polyurethanes, they continue to chemically cure for up to 30 days, becoming harder as more bonds chemically form. This is why most floor polyurethanes recommend no traffic for X amount of days, or no furniture for X amount of days.
Polyurethane has both adhesive properties (which allow it to stick to the substrate it is applied to) and cohesive properties (which are the bonds that form between individual polyurethane molecules- the more bonds that form between molecules, the harder the surface of the finish will be.)
Generally when applying polyurethane to a floor, it is always best to buy a product that specifically says it is a floor polyurethane since when it cures, it will have a hard durable finish.
Water based finishes sometimes dry to a very thin finish, and it takes multiple coats to build up the film that is needed to build up enough mils of thickness to provide any sort of protection. In addition, until polyurethane fully cures (again, up to 30 days), something like a sock would degloss the finish, not necessarily scratch it. Even with oil based finishes, at least 3 coats are usually recommended for a durable finish. I would imagine that with a thin water based finish, that number might be 3-5 coats.
If you are using a Mohawk brand finish, Mohawk Hardwood Urethane Adhesive is what is recommended for their brand of wood floors, not finish-up polyurethane. It's about $99 for a 3.5 gallon bucket.

I think you hit the nail on the head. It dries in a few hours, but it doesn't mean it's hardened. Explains why my bannister feel much harder/stronger then if I touch my stair treads. I wonder how people refinish stairs if they have to stay off them for 3 - 4 weeks. Luckily for me, I have a second set, otherwise this would be impossible.

Newbie to say the least, but I just realized the finish I am using is a lacquer by Aquatec, not a polyurethane. I don't understand the difference, but I do notice that even on some steps that have been coated for a month, I can scratch the surface with my fingernail. Is this normal with any type of finish, or is there something bulletproof I should be using?
Thanks

There are various types of lacquer... but without getting into too much technical detail, suffice to say that none of them are as hard and durable as polyurethane, to my knowledge.
As I mentioned earlier, Mohawk Hardwood Urethane Adhesive is what is recommended for their brand of wood floors. You can find it online for $99 for a 3.5 gallon bucket.
You should not be able to scratch the finish with your fingernail. Is this the product you used? Did you stir the can? Lacquer needs to be stirred often as the goodies all settle to the bottom otherwise.

As noted above, lacquer is one of the softer finishes although some dry a lot harder than others. Oil base poly gives the hardest best wearing finish although I'm not positive it can be applied over new lacquer.
I don't understand the description of the Chemcraft coating, first it says it's a waterborne polyurethane and then it says it's a lacquer

That is definitely the stuff I have...thoughts?

Me either. It doesn't look like Mohawk is offered here in Canada at least not at the big box hardware stores. Any other recommends on other oil base polys to try? I have a few steps I re-sanded so I can try out other alternatives if there is no point in using what I have (Aquatec lacquer or poly...I don't think ChemCraft even understands the difference!).

I just have oil base Minwax on my floors and it's held up fine. You should be able to find the better floor polys at your local hardwood retailer.

Just to update, I contacted Richilieu and explained the story. Whether it's one coat, or 4 coats, and staying off them for weeks to let cure (there are some that have been coated for a month and last night I was able to scuff them just by turning on a step with my socks on) doesn't seem to matter. I have one I am testing that I skip over just to see if it makes a diff after 3-4 weeks, but my process has been the same every time so I really don't think it's going to make a difference. It's supposed to be high grade stuff that is used on gym floors, so they were quite surprised when I said I could scratch it with my socks or fingernail. Anyway, just waiting for a call back from their sales guy.

Just spoke to the dealer, they seem fantastic and know what they're talking about. In fact, they're going to check it out and see what may be happening.

Sounds good, let us know the outcome.

Hey all,
Sorry but I have another post going in the finishings forum from earlier today about the streaking problem I'm having with a lacquer I am using. Not sure if they can be combined or not, but wanted to update as far as this original post is concerned.
I had the company swing by today to check out my work. Basically, I was told the problem is I applied a water based lacquer over oil based stain (both bought from the same person at the same place...surprised they sold me something that would not work together). Long story short, even after weeks of curing, I can scratch the finish with my fingernail no problem, without much pressure.
They also felt the stain was not penetrating into the wood properly, but sitting on top. They commented how some looked good because of the shade variation with the grain. I did all steps in the exact same way, not leaving the stain on for long (it's the darkest stain they offer), and wiping it dry and making sure I wiped the heck out of it.
I was told they can try to match the oil based stain with a water based version, but I need to basically sand down the steps completely back to square one and do it over again. Then, apply the same lacquer (they said it was poly even though it says lacquer on the jug of Aquatec...so I guess it's both!) and see how it goes. Also, they said there was some sort of product that can be added to the poly/lacquer (take your pick I don't know anymore!) to make it not dry as quickly...which I think is part of the problem with applying using a sponge brush..leaving marks, etc. because it dries so quickly.
Long story short, I think I'm done attempting this...especially because I have done this more than once and it's just been a complete waste. I'm going to hire an expert to come in and either fix them, or rip 'em out and put a new set in. Looking back at the time and money spent, I would have been better off having it done right the first time
Thanks everyone for your suggestions along the way. This DIY'er is retiring!

Hate to hear that the job has gotten to that point
While I seldom use a waterbased poly, they've been used successfully over oil stains for years. The main thing is the oil stain must be given more time to dry. Flood's Flotrol and XIM's Extends can be added to latex paint to slow down the drying time, not sure if they are compatible with your poly/lacquer.
There is no need for your stairs to be ripped out and replaced. Most any floor finisher can strip/sand the existing finish, restain and finish. The biggest issue will be finding one that is willing to devote the time to a small job. It's always best to get multiple quotes and check references!






Tags: poly, finish, stair, treads, scratches, very, easily, have been, water based, with fingernail