LumberJocks

Sanding Sealer... To Use or Not to Use

  • Advertise with us

« back to Finishing forum

Forum topic by jasonallen posted 11-11-2014 01:23 AM 1601 views 0 times favorited 10 replies Add to Favorites Watch
View jasonallen's profile

jasonallen

175 posts in 1086 days


11-11-2014 01:23 AM

Topic tags/keywords: finishing lacquer sanding sealer

So, I’ve always used Minwax sanding sealer after staining a project and before using Minwax brushable lacquer. I’m not sure why… I guess because long ago I was told to do it. I’m not sure exactly what it does that lacquer doesn’t do. I know of some people who just go straight from stain to lacquer. I’ve been told it’s just lacquer that has been thinned a bit with lacquer thinner. My question is, is it really necessary or am I just wasting time?

-- Skill and confidence are an unconquered army.


10 replies so far

View AandCstyle's profile

AandCstyle

2572 posts in 1722 days


#1 posted 11-11-2014 02:21 AM

Jason, I can’t really answer your question, but I will tell you what I do and you can decide if it makes any sense to you or not.

I use mostly qswo and like to pop the grain so I spray Target’s WR40xx (I use the clear). It is a linseed oil water based emulsion. The oil pops the grain. Then I spray Target’s EM1000 to give the finish a little extra depth. Finally I topcoat with EM6000.

I have used some variation of this basic process on my more recent projects (excluding boxes and cutting boards) and have been very happy with the results. HTH

-- Art

View pintodeluxe's profile

pintodeluxe

4858 posts in 2278 days


#2 posted 11-11-2014 04:34 AM

Nope. The only reason to use sanding sealer is it supposedly sands easier. I find lacquer sands out easily, and I have never had any adhesion problems. That way I only need to stock one product. I use Rudd satin lacquer and spray it. Two coats and you are done inside of a day.
Good luck

-- Willie, Washington "If You Choose Not To Decide, You Still Have Made a Choice" - Rush

View Fred Hargis's profile

Fred Hargis

3945 posts in 1958 days


#3 posted 11-11-2014 05:02 PM

I agree with not using it. You’re just wasting your time and money; maybe you were told to do by someone at Min-wax?

-- Our village hasn't lost it's idiot, he was elected to congress.

View buildingmonkey's profile

buildingmonkey

242 posts in 1013 days


#4 posted 11-11-2014 07:20 PM

As long as you are using a lacquer sanding sealer it is ok. Sherwin williams had easy sand, which you could just barely touch with a sanding sponge and it was ready to coat with lacquer. If you are using varnish for a final finish, you can also use lacquer sanding sealer, as the thinner in the final finish will not loosen the sanding sealer. You just can NOT use lacquer over a varnish sanding sealer, as the lacquer thinner will loosen the varnish sanding sealer.

-- Jim from Kansas

View Jim Finn's profile

Jim Finn

2413 posts in 2387 days


#5 posted 11-12-2014 12:26 AM

Try using just lacquer as a sanding sealer and find out for yourself. I started doing it that way but found out I preferred using lacquer sanding sealer and then brushing lacquer. I now use shellac as a sanding sealer and then I wipe on poly. I am finishing cedar and oak mostly.

-- "You may have your PHD but I have my GED and my DD 214"

View NoThanks's profile

NoThanks

798 posts in 994 days


#6 posted 11-12-2014 12:46 AM

I always figured the sanding sealer was cheaper than the lacquer so I would do all my build up coats with the sealer, (besides it sands to a powder better than the lacquer), then do my last final couple of coats with the lacquer.
But now I’m using pre-cat and using it as a self sealer.

-- Because I'm gone, that's why!

View jasonallen's profile

jasonallen

175 posts in 1086 days


#7 posted 11-12-2014 12:53 AM

Thanks for all the input. I always hate to “experiment” on a project without asking for some opinions first, especially with finish.

-- Skill and confidence are an unconquered army.

View ,'s profile

,

2387 posts in 3012 days


#8 posted 11-12-2014 02:10 AM

I think some lesser quality lacquers worked better with a sand sealer step, but we use a higher quality pre cat ML Campbell product that does not require any use of a sand and sealer. So we just use the top coat pre cat as its own sealer. It is true that sand sealermis a bit cheaper in cost and building with this product could achieve some cost savings, but overall savings is too small to justify having to deal with 2 separate products. It is also advisable to never use a softer product as a sealer than your top coat. So if using a sanding sealer, it better be comparable to your top coat.

My recommendation is to go with a high quality pre cat product and not use any separate sealer.

-- .

View Rick M's profile

Rick M

7923 posts in 1845 days


#9 posted 11-12-2014 06:43 AM

The only time I use sanding sealer is occasionally I get a piece of wood that just won’t sand smooth, usually just in one or two spots. I slap on a coat of sanding sealer or thinned shellac and that hardens the fibers enough to get it smooth.

-- http://thewoodknack.blogspot.com/

View AlaskaGuy's profile

AlaskaGuy

2406 posts in 1774 days


#10 posted 11-12-2014 05:45 PM

A. Michael Dresdner: “Sanding sealer is never mandatory—it is an option that saves time and material in some situations, and is unnecessary in others. Some woods, like cedar, spruce, and poplar, are so porous that they tend to suck up the first few coats of sprayed lacquer as if nothing were applied. Other woods, such as walnut and mahogany, require a good bit of sanding to level the pores even when pore filler is used. In both cases, the material of choice would be something that builds up quickly and is very easy to sand. Enter sanding sealer.

“Sanding sealer is lacquer, or some other basic coating, with zinc stearate added. The stearate, which is a soft, fluffy soap, adds loft to the lacquer, making it build up and fill in pores much faster. It also makes the lacquer softer, and acts as a lubricant when sanding, so that sanding sealer powders off quickly and easily. These characteristics make it ideal for trimming both the number of coats and the amount of time spent sanding them. This is especially helpful when you are trying to build a perfectly flat, pore-free finish. It is useless, in fact, counterproductive, for the open pore “natural” look finishes more popular today.

“A word of warning is in order. The stearates make sanding sealer rather soft. If you put a hard, brittle finish, like lacquer, over a thick, soft one, like sanding sealer, it is much more likely to chip and crack. For that reason, if you use sanding sealer, stick to one or two coats at the most, and plan to sand most of it back off. For the same reason, and because it tends to shrink as it cures, it is not advisable to use sanding sealer instead of pore filler.”

From the Woodworker’s Journal eZine archives


It’s important to recognize that the term “sanding sealer” means different things to different wood finishers. Many people use nothing but a coat of dewaxed shellac as a sanding sealer. Zinsser SealCoat, a pre-mixed 2 lb. cut of crystal-clear dewaxed shellac, is one of the most lauded products in this category. It works great for sealing raw wood and as a barrier coat between two possibly incompatible finishes – like an oil-based stain and a waterborne top coat. It dries super-fast and sands very well.

What SealCoat doesn’t do is offer lots of fast surface build. If you want a sealer that will help you stop up thirsty pores and smooth out the surface of the wood, you’re better off with the stearated variety of sanding sealer mentioned above. General Finishes EF Sanding Sealer is a high quality acrylic waterborne sanding sealer that builds fast and makes sanding smooth and easy. For wood with large, open grain, such as walnut or mahogany, sanding sealer is especially handy as a final fill after most of the grain has been evened out with grain filler. Now, what is “grain filler” and what’s it good for? See “Using Wood Grain Filler” here on the Rockler Blog.

-- Alaskan's for Global warming!

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com