Return to the Woodworking Forum | Post a Follow-Up

 o
varnish vs. polyurethane question

Posted by newhomeownerco (My Page) on
Sat, Oct 8, 05 at 12:45

Hello! I'm new to this forum. I'm usually on the kitchen forum since we're in the middle of a diy complete remodel. But I have a question about varnish vs. polyurethane and thought this would be the place to ask! First, what is the difference between them? We bought some legs online from a place in vermont and fashioned our own desk end (didn't like the one we bought through the cabinet company). After talking to a guy at a local paint/stain supply place and based on a sample we did on scrap cabinet wood I bought varnish and put three coats on the legs and we installed. Now the counters are in so it's a little too late but it looks basically unfinished! I chose dull finish based on the sample we did in the store (our cabinets finish isn't remotely shiny and the sample matched well) but now I'm afraid I either used the wrong product (i.e. should have used polyurethane) or that my three coats of dull varnish won't sufficiently protect the wood. Any advice or guidance?

Thanks in advance!!!


Follow-Up Postings:

 o
RE: varnish vs. polyurethane question

Technically polyurethane is a kind of varnish. Varnishes are processed mixtures of oil and resin. Polyurethanes use synthetic resins, while what is usually called "varnish" uses natural resin. That aside, I'm not clear on what your problem is. Is it that you've changed your mind and now want a higher gloss? Did you expect a thicker, smoother coating? Three coats is usually plenty.


 o
RE: varnish vs. polyurethane question

I guess I expected a thicker smoother coating. It still looks like raw wood to me...and still feels more like raw wood. I'm not sure what the difference was but in the store when we tried it on a sample of cabinet wood (but on what should have been an unfinished side) it felt smoother and felt "coated" so I was put off by what it feels like now. I just wanted to make sure we hadn't done something wrong I guess. It would be a shame if it got ruined because we didn't finish it properly...

For future reference, is there any advantage to one or the other?


 o
RE: varnish vs. polyurethane question

Three coats is usually sufficient for protection, but won't give you much "build". If you want a thicker, smoother coating, try a rubbing polyurethane like Minwax. Poly is thicker than varnish, so each coat of poly is roughly equivalent to 2-3 coats of varnish, in my experience. You should be able to apply the poly directly over the varnish after a light sanding.


 o
RE: varnish vs. polyurethane question

First question is---Did you use a 'clear' varnish? Oil based finishes generally add an amber tone to whatever is finished.

Water based and 'clear' oil based finishes are rather bland looking.

Wiping finishes by design are thinner than finishes intended to be applied with a brush or roller----necessitating twice the number of coats to achieve the same general protection/color of regular finishes.

In your case, I would get a small can of oil based satin varnish and add one coat to the legs to see if that fixes the color/quality of the finish.

The explanation Jon gave is correct---and three coats of any regular(non-wiping) varnish is the normal recommendation.


 o
RE: varnish vs. polyurethane question

For what you are doing both finishes will work fine, most spray applied finishes are better but oh well. If your coats are rough it is because you aren't sanding between coats, 280 - 400 grit. Or you're getting airborne dust which is common with slow dry finishes such as you are using.


 o
RE: varnish vs. polyurethane question

Regarding varnish vs polyurethane, I don't think you necessarily chose the wrong product. I'm curious about the dull finish you say you selected. I'm also curious to know if you sanded between coats. Varnish takes a while to dry, so it tends to collect bits of airborne dust, making the surface feel slightly rough when it's dry. Also, if it is a dull finish, I suspect it requires thorough and frequent stirring to keep the flattening agents suspended. This can introduce airbubbles that will also contribute to a less than smooth finish. By the description, dull finish would seem to indicate to me that it won't produce a shiny gloss finish, regardless of how many coats you apply. Would you consider a semi-gloss or gloss finish?

I would first do a light sanding of the surface with a fine grit sandpaper. Nothing coarser than 220, higher grit if you have it available. Once the surface feels smooth, make sure it's wiped very clean of all dust and apply a coat of either semi-gloss or gloss varnish. Hopefully this will give you the look and feel you are trying to achieve. Good luck.


 o
RE: varnish vs. polyurethane question

Sanding sealers are typically used with varnish due to the thinness of the coating. This eliminates raising of the grain as new layers of varnish melt a bit of the previous coat raising the grain even after sanding between coats.
Poly does not do this amd does not require sanding sealer but does require scuffing between coats as it does not melt a bit of the previous coat.


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Woodworking Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here