# More coats poly = more scratch resistance?



## LiveEdge (Dec 18, 2013)

I'm nearing the finished stage for an alder table I'm building. I've finished the base and non-essential parts with water-based poly, but I'm planning on switching to an oil-based poly for the table top to add heat resistance. I wondered if more coats will also provide more scratch resistance? Seven coats better than three? Or does it not work that way. Alder is fairly soft, so if I could add a little protection, that would be great. However, my wife does not want a "shiny" look so I think other finishes are less of an option.


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## bbc557ci (Sep 20, 2012)

I would think the more layers of finish applied, the deeper the scratch can be before ya hit wood.


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## LiveEdge (Dec 18, 2013)

Maybe I should use a different word. How about "ding" resistance? In other words, does poly actually add to the "hardness" of the surface?


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## Dal300 (Aug 4, 2011)

In my opinion probably not, but you are not limited to Poly.

Poly will mark pretty easily. Have you thought about using a lacquer finish and when it needs a repair here and there you can dab on a bit and it will melt the old finish and then blend in?


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## LiveEdge (Dec 18, 2013)

I have not thought of lacquer due to the "shiny factor". As mentioned, my wife wants to keep the shiny to a minimum.


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## tefinn (Sep 23, 2011)

The "shiney" factor only depends on what sheen of finish you use. If you use a satin poly or lacquer you won't have much of anything in the way of "shine".


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## woodbutcherbynight (Oct 21, 2011)

*+1 tefinn*, a lot to be said about satin or semigloss even.

If you want hard poly is on the softer side, try lacquer. Just a thought.


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## ClintSearl (Dec 8, 2011)

Waterborne poly floor finish will offer as much protection as anything else. I like Bona Mega or Varathane.


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## LiveEdge (Dec 18, 2013)

Hmm. I didn't know lacquer comes in a satin. Can I apply it without specialized tools like a sprayer?

As far as the floor poly, I've heard water based poly isn't very


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## tefinn (Sep 23, 2011)

+1 on what Clint said. Floor finishes are harder wearing. They have to be.


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## mojapitt (Dec 31, 2011)

I don't think any normal finish makes it scratch resistant.


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## LiveEdge (Dec 18, 2013)

I'm not expecting it to turn to steel, but I wondered if I should figure this into the equation. If it doesn't matter, then I'll probably go with the poly since I at least have experience with that on other projects I have done.


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## LiveEdge (Dec 18, 2013)

So I put on the first coat of oil-based poly last night. 12 hours later it is still mildly tacky. The can says I could reapply in 3-4 hours (which surprised me, I thought oil based takes a long time to dry). Should I just continue to let it dry until it isn't tacky before sanding and a new coat? The can said to apply a THIN coat (they actually used all caps), but it's hard to know what's thin and what isn't.


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## ClintSearl (Dec 8, 2011)

Why did you ask for advice if you weren't gonna take it, anyway?


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## Mahdeew (Jul 24, 2013)

LiveEdge,
You ploy will dry when it wants too. With the cold weather it takes a lot longer, humidity does the same thing. Home you used Cabot, not minwax. You can change the gloss of both poly and lacquer by sanding. You have to allow the poly to fully dry before putting additional coats or you will have a big mess on your hand. And yes, the more coats the better because you can eliminate future scratches by sanding and buffing. Most everything I have posted here as a project is poly finished and brought to a gloss and mirror shine using poly. If your wife doesn't like gloss, don't go past 1500 with your sand paper.


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## LiveEdge (Dec 18, 2013)

Clint, I definitely took this thread into account. It seemed like there was a varying opinion and I weighed the possible pros of the lacquer against the cons of never having tried to apply it before.

I will wait until it's fully dry before adding another coat. Thanks for the help.


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## BLarge (Aug 29, 2011)

Oil based poly will be your hardest, least fussy finish IMO. I use water based poly on a lot of projects because I do a lot of Milk Paint. WB is less resistant to scratches and nicks in the finish. But here's the thing, if you wet sand flat and rub out your tabletops, which you should, you can always go back later and renew the perfect top by resanding to get the deeper scratches and re rubbing the finish to the sheen of your choice. So I would go thicker on the table top with this process in mind. You can load up nice thick poly coats with a brush, no concern about brush marks because you'll sand them out in the end. I'd say 8-10 is not unresonable. A good 5 sprayed is ideal, with less flattening effort when wet sanding. The think I don't like about Water Base is it does wash out the beauty of the wood if it is darker…. If you are dying it darkens, I'd go Oil based and think about the slight darkening it will give you before you apply.

Go all Water Based or all Oil… Don't mix IMO… But in the end, experiment, have fun, learn


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## Fuzzy (Jun 25, 2007)

You can apply 10 coats of finish, and that is exactly what you will have … 10 coats of the same thing as the first. I like to use a good grade of poly, but I do it a bit differently than most folks. I thin my finish approx. 30/70 POLY/VM&P NAPTHA. Wipe it on in very thin coats … it applies without brush marks … dries quickly … loses that plastic look & feel that poly is so famous for. You can apply 3-4 coats in a day in normal weather, and it only takes a few seconds to do.


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## LiveEdge (Dec 18, 2013)

Here's a sneak peek at it. I'm excited with how it is turning out. I promise to post as a project when it's really done and I'll include some more detailed pictures.


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## Mahdeew (Jul 24, 2013)

Beautiful, excellent job.


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## Grandpa (Jan 28, 2011)

back to the question. The more particles of plastic it has the harder the surface. Use several coats of Verathane high gloss because it has the most poly then use a coat of satin to take the shiney off. The more shiney the more plastic. If it didn't dry you probably didn't stir it well. Stir it for 10 minutes and time it with a watch or clock. Then it will cure as the can says.


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## LiveEdge (Dec 18, 2013)

10 minutes?!? What sort of sadist are you?


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## Grampa_Doodie (Feb 9, 2012)

Very nice table!!

I built a similar table a couple years ago. I used all oil-based products. A few brushed-on layers, but mostly wipe-on poly. (I'm hooked on wipe-on.) I kept track of every single layer I laid down so that I could replicate it on the table leaves. (leafs??)

Once I completed the table top finish, I counted 28 coats. People ask me, "Why did you put down 28 coats?"

My reply, "Because I just couldn't go 29." 

The table has just a couple dings in it. I dropped a bottle of wine on it the very first day I brought it up from my shop. Some people call that ding "character". To me, it's still just a "ding".

Can't wait to see more photos of your project!!

Gramps.


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## Gene01 (Jan 5, 2009)

Since I almost always apply a coat of wax on my stuff, I apply it with 0000 Liberon wool. It does break the sheen and leaves a nice silky smooth surface. But, I'm definitely going to try Fuzzy's formula!


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## lumberjoe (Mar 30, 2012)

Fuzzy is also right about scratch resistance. It's a film building finish. The more coats on there are not going to help you in the scratch department. If you scratch it, you scratch it. That's it. More coats may help protect the actual wood from scratches, but if that's the goal, stop taking knives to your table top.

Poly is actually a bit better than lacquer in that regard. Lacquer (and shellac) dry really hard. The harder something is, the easier it is to scratch (more surface tension). Poly is pretty soft as far as finishes are concerned.

Thinning is the only way I apply poly and it's pretty fool proof. On this table top below, I broke all the "rules" of a poly finish:

1 - I shook the hell out of the can. Stirring is for suckers
2 - I thinned it 60/40
3 - I used a crappy foam brush
4 - No sanding between any coat at all

Your penalty for thinning is you have to apply more coats.

The finish on this POS table perfect. Not a single brush mark, run. or sag to be found.










After a full week of cure time I rubbed it out with #0000 Steel wool and paste wax


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## Grandpa (Jan 28, 2011)

Yes 10 minutes stir time. There is a hardening agent or catalyst that is your varnish. It settles to the bottom and it takes forever for the varnish to cure and harden. If you stir it back into solution it will harden. You can spend 10 minutes now or 3 days later. Your choice. I find that most people give it what we call a lick and a promise and apply the varnish with about a minute stir so I just watch the clock and get the good stir for the good cure.


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## spcbike (Dec 30, 2012)

I have been cutting my poly with mineral spirits. Fuzzy say's he uses VM&P NAPTHA. have I been doing this wrong?


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## Gene01 (Jan 5, 2009)

Just a supposition, but I'd guess the Naptha as a thinner will cause the finish to dry faster.


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## Fuzzy (Jun 25, 2007)

YEP … plus VM&P NAPTHA has to abide by certain standards whereas mineral spirits have a lot more latitude as to their composition & distillation. NAPTHA will tend to be a lot more stable across brands & lots of product. A plus is that it also dries faster, making the surface more quickly available for another coat. If you add a coat within a few hours, it is not necessary to do any kind of scuff sanding … longer than that, and it is recommended to wait several hours and lightly sand for a better mechanical bond. Being retired with plenty of time on my hands, I can sometimes get 6-7 coats on a project in a day. That makes it easy to be completely finished (pun intended) in 3-5 days … about the time you'll spend waiting for a thickly applied finish to dry + the time you will spend sanding & rubbing out all of the little dust nibs. I wipe on my ultra-thin finish, and never have a brush to clean … I use some folded up paper towel wrapped inside a chunk of old tee shirt … using latex gloves, I simply wipe on the finish … pull the gloves over the applicator … toss the whole shebang in the stainless steel sink or a fireproof can. It really isn't much of a fire hazard though, because with two latex gloves tightly encapsulating it, the oxygen can't get to it fast enough to cause spontaneous combustion. They DO however make great firestarters when winter kicks in and I need to light up my wood burning furnace.


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## BKSLDR7 (Jan 21, 2011)

I almost always use poly for furniture finishes. Usually I like satin rather than gloss and oil based rather than
water based. I like the slight amber color of oil based poly. That said, I did use oil based poly on an oily goncolo alves croquet mallet set once that was a disaster. I had to strip it all off and switch to water based as the oily wood prevented the oil based poly from ever drying.

You might want to try putting on the poly with a lintless cloth pad. I was always afraid to try it, using a brush instead. When I refinished a cherry coffee table recently, I took the plunge. I'm glad that I did. One has to put on more coats(4-6 vs 2-3) that way because they are thinner than those put on with a brush but the quality of the finish is superior, especially for table tops. There are virtually no bubbles or imperfections. Thin the poly as others have mentioned. Just wear nitrile gloves(the blue ones-latex gloves are more permeable to many of the hydrocarbon toxins-latex is more suited to physicians' exams than working with chemicals) and submerge a lintless cloth(I used a piece of old, white, cotton sock that had been washed many, many times) in the poly, squeezing out any large excess. Wipe the finish on, limiting the passes to just one or two to spread out any puddles. It sets sooner since the coat is thinner but there is adequate time to complete the coat. Make sure that you use fresh poly that hasn't been sitting around in the can for a year or more. Old poly develops little gritty particles of partially dried material that can mess up an otherwise nice finishing job.

Cold, humid conditions will definitely delay drying of polyurethane by a number of days sometimes, especially thicker brush coats. After most of the solvent has evaporated(24 hours or so) I sometimes move the piece into a heated area if the shop is cold or damp. Oh, shaking the can doesn't hurt when applying with a pad as someone else mentioned but I prefer to stir to mix and stir again often to keep everything suspended.


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