# The Shellac hoax



## ClintSearl (Dec 8, 2011)

Conventional wisdom has it that new wood should be "sealed" with shellac to start the finishing process. That's pure baloney promoted by Zinsser to sell their products. Any kind of resin finish will "seal" itself. For an expose of the shellac hoax, check out Bob Flexner's article in the September issue of *Woodshop News*.


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## NiteWalker (May 7, 2011)

It's not a hoax when using waterborne finishes.

I've done plenty of finishing with zinsser sealcoat and without it before applying my choice finish, crystalac super premium. Much less, if any grain raising with the sealcoat. I realize I could use any number of oil based finishes first, but they take too long to dry for my preference, plus I can tint the sealcoat if necessary with transtint, which I've done before as well. Sealcoat dries in less than 30 minutes.

Even Marc (the wood whisperer) did a recent project (stepping stool) where he sealed the stool first with a coat of sealcoat and then went on to use minwax poly wiped on. He did this because he'd have to put more coats of the poly if he didin't seal the wood first.

I like flexner's book for the most part but I really don't agree with some of his beliefs.

If sealcoat is baloney, why does it work so good?


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## JGM0658 (Aug 16, 2011)

Nor is it a hoax if you are going to stain. Then again any sealer would do, not just shellac.


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## bhog (Jan 13, 2011)

The only hoax I know of that involves shellac is that its not durable,etc.


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## OggieOglethorpe (Aug 15, 2012)

The huge beauty of shellac is that it's a barrier. This is lost on folks who use typical home center products, as they dry too slowly to be used with the barrier.

As NiteWalker mentioned, it can prevent waterborne finishes from raising grain. It can also prevent oil based brush or wipe-on varnishes from moving oil-based stain pigment around.

Also, shellac can act as an "undo" between professional dyes and pigment stains. Dye the wood, coat with shellac, apply dry brushed pigment stain. Don't like the pigment? You can wipe it off with mineral spirits without disturbing the dye! ;^)

Shellac is also a wonderful finish in itself. It dries super fast, wiping to a wicked fast, shiny build, and it wet sands nicely using mineral spirits as a lubricant.


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## shampeon (Jun 3, 2012)

So you're saying that a company is promoting the use of its product to accomplish a necessary task? Horrors!


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## wormil (Nov 19, 2011)

Here is the article:
http://www.woodshopnews.com/columns-blogs/finishing/502292-shellac-as-a-sealer-its-all-just-hype

Basically he makes the wrong argument… that shellac is difficult to use. I don't find it difficult to use. In fact I find it easier than poly or varnish and more durable than wiping varnish unless you build up a lot of coats. A sealer coat of shellac sanded smooth is much faster and easier than a sealer coat of varnish and much easier to sand. Plus I like the amber tint.


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## REK (Aug 30, 2009)

wormill, nice article the guy gave his opinion, good read. I think we all have our own stiles and preferences. 
Quite frankly I love zinsser products.


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## oldnovice (Mar 7, 2009)

I have used Zinsser shellac and it turns out really beautiful on most any wood because it gives it a warm glow, which is desirable in some cases. I also use the wax free variety as a sealer for lacquer.

I use a larger variety of finishes and try to use a finish that enhances the look of the project instead of having a favorite finish …. or perhaps I am reading too much into the responses posted here?


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## wormil (Nov 19, 2011)

Recently I found a can of Zinsser shellac that's probably several years old. 'It's no good,' I thought. Used it on a footstool project anyway and it's as good as the day I bought… so far, hoping it doesn't wrinkle.


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## Loren (May 30, 2008)

Woodshop Newsw is worth reading, but the target readership
is shops with higher-volume spray setups and low-dust 
spray booth setups. I reckon Flexner is advocating for skipping
the changing of finishes (and solvents) in spray equipment.
That's fair, because shellac will gum up in the nozzle if you
aren't spraying it in shorter intervals. If you are spraying 
another finish on top you have to have another gun and
keep the flow-through on the shellac gun going too.

Sounds like multi-guy shop activity to me.

I use shellac a lot. I never spray it. It dries fast. It is compressible
and polishes out well. It seals pitchy woods like pine for painting 
very well.


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## NiteWalker (May 7, 2011)

@wormil: According to zinsser; their shellac products have a 3 year shelf life.


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## bluekingfisher (Mar 30, 2010)

Very interesting topic and useful to know the properties of Shellac


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## Earlextech (Jan 13, 2011)

For me, shellac and/or sealcoat, are the easiest to use and get great results from, out of all other finishes. Sprays great right out of the can, brush, roller or rag it on, it's hard to screw up.
Keep in mind that there are as many different ways to finish as there are finishers. Writing a book about finishing is problemary because once you get past the science, it's all personal opinion and experience.


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## dhazelton (Feb 11, 2012)

Excellent sealer. As a painter I've used BIN and Bulls Eye primer for years on smoke and water damaged ceilings or knotty wood. It's basically white pigmented shellac. Don't bother with Zinsser's latex based stain-blocking ceiling paint - it doesn't and it isn't. Need to go to their shellac or oil-based products to cover. Most wood pieces I refinish are done in clear shellac followed by rubbing with 0000 steel wool and clear paste wax. Wood should invite you to touch it - not look like a piece of plastic.


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## BillWhite (Jul 23, 2007)

The best part of this discussion is that I don't have to quit using shellac.
It is kinda like my old C'man King Seely drill press. It still works very well even though its old school.
Bill


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## RussellAP (Feb 21, 2012)

Nonetheless, shellac is good stuff. The frame for my shop sign was shellac'd and it's outside and still looks brand new. I didn't even use anything beyond shellac.


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## Wildwood (Jul 22, 2012)

"It's not all hype!"

Bob, doesn't tell you there is a time and place for both dewaxed & shellac with wax. Waxed shellac is great for new furniture where shellac going to be final finish. Dewaxed shellac great for pre-staining, end grain, blotchy woods, and woods with high tannin content. Of course up to you to used eith waxed or dewaxed shellac as final finish.

Experienced refinisher and finishers know when to use either waxed or dewaxed shellac to obtain color needed for a piece working on.

It is true many stain/finish manufacturers recommend a pre-stain conditioner product when using their product on softwoods or porous woods. Is that hype check MSDS for the pre-stain conditioner product! Dewaxed shellac might be better option. Some stain manufacturers do recommend you not use shellac with their stains because it distorts color of stain.

Bob did not mention 1lb cut or less spit-wash coat. Difference between spit-wash coat and sealer coat is the cut or shellac to alcohol ratio. Both cuts do same thing!

Before 2 & 3 lb cut cans of shellac arrived at stores refinishers and finishers have been using a spit -wash coat 1lb cut of shellac as a sealer or barrier coat between other finishes or stains for very long time


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## Cosmicsniper (Oct 2, 2009)

Not sure about the hoax? Zinnser can promote its product however it wants and in my opinion it's valid.

For me, dewaxed Sealcoat is the MVP of products. There are simply things I cannot do with out it, particularly if I seek to deliver color to the wood. It's my main vehicle for adding dye colors as a toner and it always gets used to seal the wood before a stain, which I absolutely abhor otherwise.

But yeah, shellac isn't needed always. But the great thing about it is that there's really no place you can't use it. It's so universally compatible with just about any other product you use. When in doubt, bridge your coats with shellac, particularly if you are wiping/brushing on a film finish (like poly) that uses the same solvent as what you are putting it over. I can't tell you how many times I've rubbed off a gel stain because I neglected to bridge my poly coats with some shellac sealer.


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## lumberjoe (Mar 30, 2012)

To clarify a point, shellac was heavily marketed as a sealcoat. It's not really a "hoax". Back when home woodworking became popular, shellac was pretty much all you had to work with as a hard, durable finish coat. Then came along a whole host wiping varnishes like Formby's tung oil finish (contains absolutely no tung oil), Waterlox, etc. which were much easier to work with. To stay relevant in the market, Zinnser pushed the seal coat properties and aspects of shellac. Rather than try to compete with the huge storm of new products people were snatching up, they pushed their product as complementary to varnishes; not an alternative or replacement of - which shellac essentially is.

I was always taught (and just read a book that reinforced this) that the shellac seal coat is not as necessary as people make it out to be. There are a few uses where it excels (I am talking about shellac as a seal coat, not a finish coat):

1 - before waterborne finishes (as mentioned)
2 - To seal off overly oily woods or sappy knots (like in pine)
3 - Odor barrier used when refinishing (pet stains, smoke, etc)

Other than that, your first coat of finish is your seal coat. Shellac is just another finish. It works well as a barrier for the list above, but any other finish will do just as good of a job sealing the wood. I've never seen this happen personally ,only in pictures, but because shellac dries SO HARD it is possible to crack it under your actual finish with some concentrated force.

In addition, dewaxed shellac offers much better moisture resistance than the waxed variety. Since shellac has a short self life, if you use it a lot it is cheaper to cut your own.


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## shampeon (Jun 3, 2012)

The advantage of using shellac, Zinnser or homebrewed, as a seal coat is that shellac is compatible with pretty much any other top coat you might have on hand. It's also great as a barrier coat when using incompatible finishes (waterborne over oil-based, for the classic example).

Yeah, you don't have to use it, especially if you're using a single vendor for all your finishes.


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## ClintSearl (Dec 8, 2011)

Thanks, Guys. It's most amusing to read all the rationalizations for using shellac. I've been woodworking since the mid-60's, and have never used shellac for or on anything. I'd match my finishes to any for looks, durability, and ease of application. One day long ago in a moment of weakness I bought a couple pounds of super blond shellac flakes from Garrett-Wade, Constantine, or Behlen, but came to my senses and never used it. It and BLO (only good for starting fires) will never again cross my shop threshold. Nyuk nyuk.


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## CharlieM1958 (Nov 7, 2006)

This shellac/no shellac debate could be almost as polarizing and contentious as the "BLO is great vs. BLO sucks" argument.


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## lumberjoe (Mar 30, 2012)

Charlie, I agree except there is a lot of misinformation about shellac floating around and people avoid it unnecessarily. There is actually nothing wrong with shellac. I'm not sure where the "shellac sucks!" mentality came from. High end antiques and re-productions of the same are almost always finished with shellac. Also take a look at some french-polished musical instruments and tell me if you've seen a more beautiful finish. Shellac is superior to any oil/varnish blend in terms of protection. There are better choices for kitchen table tops and really high use/wear surfaces.

To contrast, all of the oil/varnish blends (danish oil, "Tung oil finish", "teak oil finish", antique finish etc) offer extremely minimal protection. They are billed as finishes that "protect the wood from within". That is complete crap. For a finish to be effective, you need to build it up. You cannot build up an oil/varnish. The wood will only take so much before you start getting a gummy mess.

In my opinion, shellac looks much nicer than an oil or water based poly and is just as protective in a lot of cases. it is also easier to get a nice looking, even finish with shellac, and it dries A LOT faster, reducing overall finishing time.


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## shampeon (Jun 3, 2012)

So you've never used shellac, but you feel so strongly about it that you're maligning it and people that use it? Ok. Got it.

This is such a waste of time.


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## a1Jim (Aug 9, 2008)

Clint
What would Scott Phillips do without Shellac ? ) It seems that's the only finish he uses at least on the two show of his I've seen. I agree with you on the BLO issue. All said and done I think you are above average on your finishing skills so you may not need Shellac but hit helps others with finishing problems ,like change from one type of finish to another or as a aide to help fight blotch on woods that have the tenancy to blotch, are there ways to prevent those problems YES but shellac can do those jobs too.


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## cutworm (Oct 2, 2010)

Me, I just like the looks of shellac. Nice warm deep look to it. I don't care for poly.


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## bandit571 (Jan 20, 2011)

There was one fellow that claimed one had to use freshly made from flake shellac, or it won't work. Turned out he was SELLING those said flakes in his store. Zinsser was cutting into his "sales". Made a regular Crusade about his Flakes being the ONLY kind to use.

He also started a Crusade against all things in a Yellow can. Minwax was also cutting into his sales of P&L 38 Varnish.


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## bhog (Jan 13, 2011)

Never used it =epic fail.You can send those flakes that you didnt use to me and lumberjoe.


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## OggieOglethorpe (Aug 15, 2012)

"So you've never used shellac, but you feel so strongly about it that you're maligning it and people that use it? Ok. Got it.

This is such a waste of time."

Exactly. A complete troll…

Imagine sharing useful information!


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## ClintSearl (Dec 8, 2011)

A hundred years from now when all you shellacophiles are looking down (or up as the case may be) and see the finishes on your projects cracking and falling away from the decay of the shellac "seal" coats, you'll finally recognize the error of your ways in the shop.

Giving away the flakes I still have would only promote continued error.

Good luck and fly safe.


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## lumberjoe (Mar 30, 2012)

I hear that argument a lot, however I feel a little differently. Unless your piece goes in a climate/humidity controlled curated museum with no UV exposure and minimal human contact, it's safe to say any finish will deteriorate and be in need of repair within it's usable life. I'd like my projects to be used as they should, and wear as they should. When they get handed down to kids, and then grand kids, what better way to pay homage to the creator than to put your personal touch into the piece and restore the finish. I recently did that with a pair of dressers that my great grandfather made in the 1900's. They were passed to my grandfather, then my mother, then on to me. They look amazing now and I thoroughly enjoyed refinishing them (with shellac just as he did originally, 105 years later). He died long before I was born but I am sure would be proud to see his work looking like it did the first time he took that step back to admire it.


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## shipwright (Sep 27, 2010)

Can't French polish with anything else !


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## lumberjoe (Mar 30, 2012)

A french polish is on my list of things to try. I just need to make something worthy of a French polish


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## Ripthorn (Mar 24, 2010)

I've used shellac on a few projects and like it pretty well. I use it to seal over the top of pine, as I have done projects with pine where the sap caused problems with the finish. Sealing with shellac helped that problem. Of course, I use my fair share of lacquer, both waterbase and solvent-based, poly, oil, etc. I think they all have their place. I like shellac for the process as well, as I find it more relaxing, kind of like the hand tools of the finishing world.


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## Milo (Apr 24, 2009)

If your refinishing furniture you save yourself a TON of headaches if you use a barrier coat of shellac. Especially, as Nitewalker says above, if you use WB finishes. Older wood gets all kinds of crap in it, and they can cause havoc with finish.

Now, if your using new wood, it might not be a problem, but if your recycling like I do a lot, shellac if your friend!


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## CharlieM1958 (Nov 7, 2006)

* "I like shellac for the process as well, as I find it more relaxing, kind of like the hand tools of the finishing world."*

I like that analogy, and I agree.


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## wormil (Nov 19, 2011)

Won't use shellac which has been around for centuries because it might crack.
Uses nitrocellulose lacquer instead which is certain to yellow and crack. It's like a terrible meme.


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## NiteWalker (May 7, 2011)

*"A hundred years from now when all you shellacophiles are looking down (or up as the case may be) and see the finishes on your projects cracking and falling away from the decay of the shellac "seal" coats, you'll finally recognize the error of your ways in the shop."*

If I'm still around 100 years from now I'll refinish any of my built projects with whatever space age finish happens to be available.


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## bhog (Jan 13, 2011)

Lumberjoe you dont need to build anything worthy to french polish.Any random piece of walnut is begging.I used alot of scraps learning to polish.Maple is a good one because you dont have to fill the grain.The first time you see it build up to a deep beautiful finish its like a child being born.


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## hObOmOnk (Feb 6, 2007)

*"Then came along a whole host wiping varnishes like Formby's tung oil finish (contains absolutely no tung oil), Waterlox, etc. which were much easier to work with." 
*

1. Formby's Tung Oil Finish has always contained tung oil, despite this persistent "Internet Echo."

2. Waterlox (original formulation) has been marketed for over 100 years. While Waterlox is thin enough to be a so-called "wiping varnish", it also easy to apply with a brush.

Blessings,
Bro. Tenzin


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## wormil (Nov 19, 2011)

Formby's Tung Oil is 70% mineral spirits and an undisclosed amount of tung oil based varnish, according the MSDS. It's not tung oil.


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## lumberjoe (Mar 30, 2012)

Correct. There has also been a debate for as long as the product has been around if it contains ANY Tung oil at all. The general conciseness is no since is makes specific mention to "tung oil finish" and not literally "Tung oil". Which is fine, it's still pretty good as far as oil/varnish blends are concerned.

"Waterlox" has been around since 1930. Before that it was marketed and sold by Empire Varnish company which was established in 1910. Around for over 100 years? Probably. Marketed for over 100 years? Almost.

Maybe you misread ore misinterpreted what I was saying. They aren't bad finishes. I love Waterlox. It's still a wiping varnish though. Mode of application does not change it's chemical composition. What I mean there is a "wiping varnish" is not characterized as to how it is applied. It is a varnish that also contains a considerable amount of solvents. Brushing it vs wiping it does not change the fact that it is a "wiping varnish" In fact, for top coats, I use "wiping varnishes" almost exclusively - whether it be pre-mixed like Arm-R-Seal or Waterlox, or I mix full strength poly with mineral spirits. I also always brush them on, even though they are "wiping varnishes". I get better coverage/control and find it to be less wasteful than using a rag.


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## Cosmicsniper (Oct 2, 2009)

Yeah, the OP has his opinions about things and they always come in an absolute voice…it is really troll worthy stuff. To make statements like, "BLO is only for starting fires" really is insulting to those people who have used it successfully for so many years.

There really aren't any bad finishes (some are worse than others). The problem is that they are so misrepresented that you must understand their best usage…even if the can's instructions says something completely different. Heck, even something like Mixwax Polyshades is workable if you know what it actually is - use it like a stain and you are dead in the water, but as a tinted film finish (especially thinned and sprayed), it's not terrible.

Keep in mind as well that shellac is one of the more easily fixable finishes, much like lacquer in that regard. Varnishes require a complete stripping after a while. Shellac can be spot treated, if you are good.


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## oldnovice (Mar 7, 2009)

*Why are so many of the forums becoming so belligerent ?*

This is the second one I opened today where insults were more prevelant than good discussion! 
Some LJ are acting like little children and/or bullies!


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## livelite (Jun 19, 2010)

Have to get in on this one. I'm fairly new to the finishing world and found that shellac is indeed serves it purpose and does it well. The versatility alone is the reason why it goes on almost all of my projects. Most of the tables made for personal use is always subject to "color" change and as a sealcoat of shellac saves a lot of time in the refinishing process. Also, the application of any dye or stain seems to go on evenly as opposed to not applying it at all. The downside is that it dries really quickly. But any corrections are extremely easy to make. I have doubts that it's a conspiracy by Zinseer. It would be nice to see the flakes sold at the home centers instead of only the cans.


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## lumberjoe (Mar 30, 2012)

Oldnovice, I'm not sure and I agree. Who knew shellac was so polorizing? This may as well be a sawstop thread.

Livelite, i haven't read the actual article, but I did mention this earlier. Zinsser *DID* sort of create a market for shellac as a seal coat. Before that, it was a finish and used as such. Instead of competing with all of the new to the home woodworking market finishes, they decided to market shellac as a seal coat as well as a finish. They made (correct) claims that it is compatible with all of the new finishes that came to market and tried to slip it in as an extra finishing step to boost sales. Also as I mentioned above, shellac shouldn't always be the first choice for a seal coat. Often times it isn't even necessary to use shellac. Your first coat if finish is your seal coat. I only use it when I absolutely have to as a seal coat. It's not the easiest stuff to work with, and it gums up sandpaper really quickly.

So yes, Zinsser did over-hype shellac as a seal coat when in reality it is a finish. But then again every finish makes outrageous claims on the can, many of which are flat out wrong.

Interesting fact I found out in a FWW article brought to my attention this week - Minwax (yes, that is a dirty word around here) wipe on ploy was selected as the best wiping varnish by fine woodworking in an article they did a few years back.


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## NiteWalker (May 7, 2011)

Joe, I remember that article and have use the minwax wipe on poly and it's indeed good stuff for when I don;t want to break out the spray gun.


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## oldnovice (Mar 7, 2009)

For wipe on/brush on poly I liked the old Carver-Tripp water based versions. When I lived in Illinois I refinished three floor with this poly. The standard heavy duty poly could be made more durable for use on floors with an additive. A pouch of the additive really provided a tough finish. 
I also used it, without the hardener, on a number of projects as there was no odor, non flammable, and water clean up.
However, Carver-Tripp was purchased by another company and I have not been able to find out who bought them and/or a substitute with similar characteristics.

I use Min wax rub on poly and General Finishes Arm-R-Seal and have never used their polycrylic which is water based.


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## pintodeluxe (Sep 12, 2010)

While I agree it is not usually needed under topcoats like pre-cat lacquer, I have found a seal coat of shellac useful as a pre-stain conditioner for blotch-prone woods like cherry.


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## vipond33 (Jul 25, 2011)

oldnovice…"Why are so many of the forums becoming so belligerent ?"

That's easy, take away politics and religion and the venting just moves elsewhere. Peoples gotta have their say.

I'll second CharlieM on re-posting ripthorn's "I like shellac for the process as well, as I find it more relaxing, kind of like the hand tools of the finishing world." 
Nice thought, well said.
gene


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## joewilliams (Aug 1, 2012)

So does that Zinsser shellac come from a red state or a blue state?...and that finish on the Sawstop is shellac..right?


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## hObOmOnk (Feb 6, 2007)

*"Formby's Tung Oil is 70% mineral spirits and an undisclosed amount of tung oil based varnish, according the MSDS. It's not tung oil."*

The actual product name is *Formby's Tung Oil Finish* and is does contain Tung Oil.

It's a fully cooked oil varnish made with Tung Oil, Modified Soya Oil and Alkyd Resin.










Blessings,
Bro. Tenzin


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## Purrmaster (Sep 1, 2012)

I find shellac difficult to use, though I am just starting out with it. I was prepared for it to be difficult though. And I'm not using Bulls Eye, I'm mixing my own shellac.

This thread raises a few questions for me:
When using stain is it not preferable to use a pre-stain wood conditioner under the stain, rather than shellac?

You can use mineral spirits to wet sand shellac? Do you mean mineral oil, or mineral spirits? I ask because I tried wet sanding some shellac with mineral oil yesterday and the results were worse than when doing it dry (I went up to 2,000 grit paper).

When sanding shellac, can water be used as the lubricant? I've read in some places that this will turn the shellac white. And I've read in other places that shellac is waterproof and using water as your sanding lubricant is fine.


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## shampeon (Jun 3, 2012)

Mineral spirits are very, very different from mineral oil. I can believe that mineral oil is a terrible medium for wet sanding shellac. I wouldn't use water, either.

I'm curious what you're finishing with shellac that needs wet sanding to 2000 grit. That seems like way overkill.


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## bhog (Jan 13, 2011)

Shampeon some go up into the micron buffing compounds with finishes.I would consider 2000 grit on shellac a semi gloss,but I am not a finishing expert by any means.


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## Purrmaster (Sep 1, 2012)

bhog hit the nail on the head. I am going for a high gloss finish and even at 2,000 grit it is still semi-gloss. I did pick up some FFFF pumice and rottenstone. And I have mineral oil (from the grocery store) and linseed oil. Plus, obviously, water. I'd prefer to use water as when I tried the mineral oil it actually stuck the paper to the surface.


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## wormil (Nov 19, 2011)

The actual product name is Formby's Tung Oil Finish and is does contain Tung Oil.

Claiming it has tung oil in it isn't very useful. It contains a tung oil based alkyd resin. Basically a fat (in this case, tung oil) is added to a polyester resin, magic happens and it becomes a varnish. I'm not an expert on alkyd resins, I don't know if the specific fat has much effect on the final finish but I suspect not. At the end of the day, the tung oil description is a marketing ploy. The important thing is that you don't confuse it with tung oil, it is 70% mineral spirits and ~30 or less % varnish.

When using stain is it not preferable to use a pre-stain wood conditioner under the stain, rather than shellac?

Some woods absorb stain unevenly causing blotching. A conditioner is just a weak finish so that areas of the wood that would absorb the most stain will fill with the conditioner first so the stain goes on more evenly. Shellac works just fine as a conditioner you just need to thin it down with alcohol first. If you don't thin the shellac it will completely seal the wood and won't accept stain.


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## Manitario (Jul 4, 2010)

I like shellac, it is probably the easiest of all finishes to use. Bob Flexner recommends shellac as a seal coat in one of his books…


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## Purrmaster (Sep 1, 2012)

I like shellac for the warm look but I'm having a hell of a time applying without brush or wipe marks. Which then requires lots of sanding which then essentially wastes the shellac.


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## ClintSearl (Dec 8, 2011)

Most of the comments have nothing to do with my original post. Key words: "new wood," "resin finishes," and "self-sealing." The majority of the responses defended the use of shellac for its characteristics in other applications, which may or may not be valid, but it's certainly true that its use as a "sealer" on new wood is unnecessary and superfluous. And in my experience, by choosing the right combination of stain and top coat, its use as a barrier isn't supported.


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## lumberjoe (Mar 30, 2012)

I agree 100% Clint


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## Cosmicsniper (Oct 2, 2009)

That's where I disagree, Clint. Using shellac on new wood is NOT unnecessary or superfluous. It's another option. A good one.

Flexner's point is that you can just use the actual finish to do these things. Yes. But that doesn't make shellac obsolete. Once you are comfortable working with it, it still does everything you need it to do in a safe way.

IMO, Flexner underestimates shellac in new wood applications and he's forgetting his roots a bit. Put down a stain and then rub on some oil-based poly and we can understand the issues and the need for "sealcoating." But we are hobbyists here, for the most part, and that oil-based poly and a can of Gel stain might be all we have. Not many of us are pros who can go out and get the latest in water-borne products and high-tech lacquers and HVLP turbine systems. Just because those technologies exist and do the job very well doesn't mean shellac (or paint brushes) isn't a viable, even terrific alternative.

You might save money in the long run with such technologies in a production environment (which would be a good argument), but I wouldn't be saving any money doing my hobby.

I love Flexner and I learned a ton from him. But I think he's focused too much on ideals there and less on our realities. For guys like me, shellac is the best, most price effective vehicle I have, especially since I use a lot of aniline dyes. And NOTHING is faster…a singular point that is really the ONLY point I need. And if I make a mistake, I put on another, better coat…voila, instant fix. Lacquers have the same properties, but much less bang for the buck. Waterborne finishes, while being fast drying, aren't as forgiving as shellac.

I'd rather use cheap, thinned shellac for my coats (washcoat, stain sealer, toner delivery, seal before top coats) than something that costs twice as much. I'll save my beloved GF Enduro-Var water-borne urethane for the final steps. At $80 a gallon, it's a crime to waste it beforehand.

Moreover, saying shellac is superfluous is an insult to those who still use shellac successfully. It'd be like me saying that you MUST have a 5hp 3ph cabinet saw just to cut wood. That'd really piss off some LJs, wouldn't it?

If there is ONE thing to be learned in woodworking it's that newer technologies do NOT make older technologies unnecessary or superfluous. We aren't dealing with PCs or cameras here. Zinsser isn't Kodak. Film maybe dead, but shellac is not. And someday, a refinisher like Bob is going to wish that people did NOT heed his advice…because his job gets tougher with every film finish you have to scrape off.


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## lumberjoe (Mar 30, 2012)

I have also learned A LOT from Flexner. I do agree that he is heavily focused on theory and real world conditions are somewhat unique to the individual. If you find something that works for you consistently, stick with it. Flexner's literature is amazing, but not a bible. Charles Neil is also an amazing resource, and has some differing opinions, especially around application of wiping varnishes. I have had much better results using Neils' methods than Flexner's in that regard. Woodworking; especially finishing is not an absolute science. I am certified in a lot of IT/Network related fields for example. There is a difference from what you *should* do, and what you *actually* do. A lot of methods only work to pass tests and have almost no validity for real world situations.

To the point of the article, it's correct. Shellac is not the end all and be all of sealers that people (and Zinsser) make it out to be. It's *JUST ANOTHER FINISH*, it's not a magical sealer that is required or even necessary on every piece you work on (as marketing would lead you to believe). It happens to be very versatile as a seal coat in some specific applications. A lot of the time, especially on virgin wood, whatever finish you are applying is just as good as a seal coat.


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## Cosmicsniper (Oct 2, 2009)

BTW, look at Bob's last paragraph in that article…

"But there's rarely a reason to use shellac in a factory or cabinet shop making cabinets and other objects out of new wood."

Remember your audience, guys.


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## Cosmicsniper (Oct 2, 2009)

Yep, Lumberjoe, I agree with you AND with Flexner. Great points. But Clint took that article and began spouting off how us "shellacophiles" will regret the stuff peeling away and flaking and all that nonsense. Clint is definitely too smart to make such declarative statements while using another author's article as a proof text. I do not believe Flexner necessarily is railing on shellac as much as he is praising the new approaches. Clint, however, is railing on shellac.


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## Cosmicsniper (Oct 2, 2009)

One more thought, there are safety issues with most film finishes when spraying that aren't there with shellac. Again, it's something that affects guys like me who either do their spraying outside or turn on every fan we own.


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## JGM0658 (Aug 16, 2011)

but it's certainly true that its use as a "sealer" on new wood is unnecessary and superfluous

You have got to be kidding. Shellac as a sealer in new wood is one of the best vapor barriers available to any wood worker. It prevents the wood from moving too much once it is assembled. Being that it is harder than Lacquer and polyurethane varnishes it is better as a barrier for sealer and it has less toxic effects than those mentioned before. Shellac it is an outstanding sealer and certainly it's use is not superfluous or unnecessary. It is a matter of choice as mentioned above, but certainly a great choice for a sealer, I don't care what Flexner states.


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## lumberjoe (Mar 30, 2012)

Please explain how shellac prevents wood movement once assembled that poly or lacquer will not?


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## JGM0658 (Aug 16, 2011)

Lacquer and poly are more permeable to humidity (also known as vapor transfer) than shellac. While any of these are better than nothing and certain lacquer sealers with high solid content are almost as good as shellac as a vapor barrier, IMO shellac is the best for this.


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## shampeon (Jun 3, 2012)

Using a thin seal coat of shellac on new wood is one of the best use-cases FOR shellac, if you intend on dying or staining the wood. It's not the only thing that works, but I don't hear anyone saying that.


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## Builder_Bob (Jan 9, 2010)

Two coats of wax free shellac allow you to stain cherry without throwing up at the result.


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## ClintSearl (Dec 8, 2011)

To put it bluntly, vapor permeability is a non issue. When, in anybody's experience, has the difference between that of shellac and anything else been a problem? Never? Sounds like a hypothetical advantage of no practical import.

Why would anyone want to stain cherry?

Don't worry, be happy.


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## JGM0658 (Aug 16, 2011)

To put it bluntly, vapor permeability is a non issue.

Really? I guess then, wood movement is not an issue. What do you think makes wood move? CHANGES IN HUMIDITY….so, to put it bluntly….yes it is an issue. This is what happens when post are made with little thought and experience about the subject. Just because Flexner wrote it, it does not make it gospel. His, like yours and mine is only an opinion.


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## NormG (Mar 5, 2010)

Great comments from all, I suppose it depends on how it has worked for your application. I have had no issues


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## lumberjoe (Mar 30, 2012)

Clint, exactly. If I were to stain cherry, dewaxed shellac is not the first product i would reach to for blotch control. There are commercially available products that are FAR simpler to apply, require less or in the case of the Charles Neil stuff, almost no effort to apply and work just as well if not better.

Poly is more permeable to moisture than a shellac finish, but is it more permeable than a shellac seal coat? Remember the strength in a finish is in its build, not necessarily it's chemical composition. With a seal coat, you aren't building any finish at all. A lot of what makes one finish better than another is the ability to build the finish without runs, sags, or gumming of the surface.


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## wormil (Nov 19, 2011)

Poly is more permeable to moisture than a shellac finish

lumberjoe, what is your source for this?


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## Cosmicsniper (Oct 2, 2009)

Didn't think of that, JGM. Good point.

I know that a lot of vapor barriers/retarders are shellac-based because of its natural abilities in that regard. It's actually better than poly, nitro, and most varnishes. In fact, in a related way, it's a key reason why people love Waterlox so much.

Though it does beg the question of how much is enough for us? Even so, it's hard to simply dismiss this fact.

BTW, my favorite fact is that we eat shellac all the time. Things like Skittles and Jelly Beans and Advil are coated in it. Yummy! In fact, more shellac is used in confections and pharmaceuticals than in wood finishing.

Just a few Internet "facts". LOL!


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## lumberjoe (Mar 30, 2012)

The chemical composition and the characteristics of the two finishes. As I stated the protection doesn't come directly from what you are putting on, it's how much you can get down before it looks like crap. Ploy cures really soft - which is a good thing in some cases. But you cannot build it up to get all the protection you can from it like is possible with shellac. Shellac cures really hard. A good real world example of this is "bar top finish", which is really just epoxy. You can build a SUPER thick finish with the right epoxy mix, which is why it is applied to wood that is guaranteed to get a wet a lot.

Another good example is surface tension. On shellac you have a lot of it because it is hard. On ploy there is not as much.
If you stretch a cotton t-******************** as hard as you can and run water over it, the water will bead off for a short time before it starts seeping in. If you don't stretch it at all, the water will just soak right in.


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## ClintSearl (Dec 8, 2011)

*JMG* I think your comment in response to my "vapor permeability is a non issue" post missed the point. I didn't say anything about wood movement, merely posed a question which you failed to address.

*Cosmic* It's my understanding that Waterlox is based on tung oil, and does not contain shellac.


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## JGM0658 (Aug 16, 2011)

merely posed a question which you failed to address.

Jesus! This is a waste of time, I addressed your question. *NO IT IS NOT SUPERFLUOUS OR A HOAX TO USE SHELLAC AS A SEALER FOR NEW WOOD. * For the reasons I stated above, e.i vapor barrier and resistance for the wood to absorb water through the air, got it? Whatever Flexner wrote I don't care, in fact I will go out and state it clearer. He is wrong, period!

I cannot explain it any clearer, if you don't understand it then that is your problem not mine.


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## ssnvet (Jan 10, 2012)

*Interesting fact I found out in a FWW article brought to my attention this week - Minwax (yes, that is a dirty word around here) wipe on ploy was selected as the best wiping varnish by fine woodworking in an article they did a few years back.*

got to keep the advertisers happy you know ;^)


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## JGM0658 (Aug 16, 2011)

Cosmic,

IMO it is the only reason why would any one use shellac as a sealer. When I am working with pine or wood that has not been quarter sawn, once I am finish prepping it and have smooth it, I give it a coat of shellac on both sides.

Anyone who has been doing this for a while has have it happen that you cut a board, you joint it and plane it and then you leave to do something else only to come back and have the very same board cupped or bowed again. Shellac prevents this to an extent. And of course if I plan to stain, there is no better way to prevent blotching.


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## lumberjoe (Mar 30, 2012)

*JGM0658*, I'm really not trying to be difficult or pick a fight. I echo Clint's question. How is a washcoat of shellac a vapor barrier of any significance at all? I honestly do not understand.


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## Cosmicsniper (Oct 2, 2009)

Didn't mean to imply that, Clint. Waterlox isn't a shellac. But it does provide a good barrier against moisture. Even so, bad illustation on my part.


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## ClintSearl (Dec 8, 2011)

*JMG* The question was: "When, in anybody's experience, has the difference between that (the vapor permeability) of shellac and anything else been a problem?" And while we're on the subject, what exactly is the difference in water vapor permeability between a "sealer" coat of shellac and poly or lacquer? Does the white ring that a wet glass leaves on a shellac finish have anything to do with permeability? Inquiring minds want to know.


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## JGM0658 (Aug 16, 2011)

How is a washcoat of shellac a vapor barrier of any significance at all?

A 2 pound coat is not a washcoat, it has a significant concentration of shellac as percentage per weight. One application is enough to soak into the the wood and prevent moisture absorption. In fact if you have ever done french polish you will feel your hand sticky because of the shellac.

Clearly if you use a 1 pound cut, then it is too thin, you might have to do a couple of applications, or spray it a couple of times as this concentration is commonly used for spraying.

It comes down to this, you do not have to believe me. Do your own tests (as I have done) and you will see the difference.

An added advanatge of shellac is that if you like what is happening, you keep applying it by hand and you end up with a beautiful shiny thin surface that people just can't resist to touch. As with everything, it has it's uses and applications, it is not a panacea that should apply to all woods in all circumstances, but for sealing, staining and prepping wood for other finishes it has no equal.


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## Cosmicsniper (Oct 2, 2009)

@Lumberjoe

I do think some clarification is in order. I'm sure you know this, but there is a huge difference between moisture and humidity. Wood moves because of humidty, not moisture. Humidity is a vapor (gas). Moisture is a wet glass. I think what JGM is saying is that shellac works best to prevent wood movement due to humidity, which is what can, in part, cause wood to warp after it's cut - though I think tension in the wood is a bigger factor, IME.

But I think we'd all agree that you don't want to set a wet glass on shellac.

The humidity/movement issue took a while for me to understand, but I think it was really driven home to me a couple of years ago when I read something that Bob Taylor (Taylor Guitars) wrote a couple of years ago. When asked why luthiers don't finish the entire guitar, Bob stated that it really doesn't matter because wood is going to move regardless of the finishes that they use…and, of course, it's not something you'd want to do with a guitar anyway from the standpoint of sound. He drove home the point that his finishes are NOT vapor barriers and will not protect against humidity. From that standpoint, using shellac is probably superior in that regard, but since you don't finish the inside of the guitar, who cares about that, right?

Likewise, it's why finishing an entire project to protect against wood movement is considered a myth by many, simply because most all finishes are gas (vapor is a gas) permeable to some extent. Shellac is widely considered to be tops in that regard, but even it is not a full on barrier to vapor…it's a retarder. So, to what degree this is an advantage over other finishes is a guess. But it's hard to argue with people who have had long success with shellac. Who are we to say otherwise?

However, it's interesting what luthiers do. Even if they don't French polish, guess what most people put on the binding and purflings of guitars during the pore filling stages to protect them from discoloration? Yep, a washcoat of shellac.


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## JGM0658 (Aug 16, 2011)

"When, in anybody's experience, has the difference between that (the vapor permeability) of shellac and anything else been a problem?"

I think you are looking at it the wrong way, it is not a matter of being a problem but a matter of being more protective.

As to the white ring, you guessed correctly, shellac is susceptible to the hydroxide ion (OH) so when you put a wet glass on shellac, the hydroxide ion wants to bind the shellac causing the typical "blush" much in the same manner when you want to spray lacquer on very humid environments.


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## lumberjoe (Mar 30, 2012)

I understand the difference between water liquid and water vapor. I was just not grasping putting a full 2lb coat of shellac down as a seal coat. I have used shellac as a finish and really like it. It's not the best for things that will get wet constantly, but in my opinion, nothing shines like shellac. Even high gloss poly gets to the point where it looks like plastic wrap before you can get it mirror shiny like shellac. I'm not sure I would use a 2lb cut under a wiping varnish though without heavily abrading it first. And that would likely defeat the purpose of a moisture barrier


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## DaleM (Feb 18, 2009)

Although I use a vinyl sanding sealer prior to spraying lacquer, I know I could just spray lacquer without the sealer with good results so the sealer is not necessary. It does, however, make it much easier to sand the wood to a smooth surface before applying the second coat of finish. So as far as a finish "sealing itself", that is not always the best option.

Also, and more to the original point, my finish using shellac as a sealer will be superior to yours without it when finishing pine with knots in it. I don't know of anything else as good at keeping the knots from bleeding through. I use Zinnser B.I.N. primer when painting pine too with good results and it's mostly shellac. On other woods I agree that using shellac is not necessary.


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## ClintSearl (Dec 8, 2011)

*JMG* *"I think you are looking at it the wrong way, it is not a matter of being a problem but a matter of being more protective."*

If there's never been a problem not using shellac, then why use it to solve a problem that doesn't exist?


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## JGM0658 (Aug 16, 2011)

I never said there has not been a problem, I said it is a better sealer. IMO there has been a problem of wood movement which shellac ameliorates, but if you don't care about this then it does not matter if you use it or not. Bottom line, you use shellac if you want the best sealer to prevent immediate wood movement.

I am not one of those guys who think that because the old timers did it a certain way it must be the right way. But in this case I do believe there is an advantage to using shellac as a sealer, just like the old timers did.

Look, do this, seal a board with shellac, one with nitrocellulose lacquer and one with poly, and see which one has movement. I think you and Flexner would be surprised. I have not read the article you mention, but unless it has some testing done, it is nothing more than an empirical opinion based on his experience and not hard data.


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## ClintSearl (Dec 8, 2011)

*JMG* *"IMO there has been a problem of wood movement which shellac ameliorates"*

Could you be more specific? Of the 43 projects I've posted on this site, without a whiff of shellac, there's never been a problem with wood movement, and I live in a climate that varies in humidity from 30 to 90 %, so tell me again why I should use it.

Whatever the difference, if measurable, in vapor permeability between shellac and anything else that I've used seems to be academically moot and practically irrelevant.


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## mountainaxe (Jul 17, 2011)

I've read all the prior postings and it does seem like everyone has their own opinion, for whatever that's worth. I just applied two coats of Zinsser to a large raw pine window-seat that measures 11' x 22" x 21". It did a good job of sealing (especially knots) and gave a great base for final painting. Why be a snob? The best testimonial for shellac as a sealer rests in its results…I'd use it again in heartbeat.


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## JGM0658 (Aug 16, 2011)

there's never been a problem with wood movement, and I live in a climate that varies in humidity from 30 to 90 %, so tell me again why I should use it.

Ah well, you live in a magic place then. That or the rest of us who have seen and experienced wood movement, who have seen cracked table tops, who have seen doors bound shut, and all those people in magazines and books who say there is wood movement with changes in humidity are just a bunch of fools who don't know what we are talking about.

Even so, if you are seeing changes in humidity inside your house from 30 to 90%, I would recommend you move out, there has got to be something wrong with that house.


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## wormil (Nov 19, 2011)

Earlier I asked where this idea came from that shellac was a better barrier and people talked around it but didn't answer directly so I did some research. It appears that shellac is slightly better than some lacquers and polyurethanes at resisting water vapor. The data is hard to read the way it's presented but if I followed it correctly, shellac was better than satin finish products and about the same as glossy. However shellac did degrade slightly faster than some polyurethanes. All in all the differences were so close as to be insignificant. Here is the file if anyone wants to root through it.

http://www.fpl.fs.fed.us/documnts/fplrp/fplrp462.pdf


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## ClintSearl (Dec 8, 2011)

*JGM* On a final note, it occurs to me that on wide glue-ups and panels, the high resistance to vapor transfer of shellac you allege would actually lead to a nasty problem. That is because the backside/inside of the panel is rarely/never finished, the differential vapor absorption occasioned by the shellac being only on the face would cause the piece to cup or warp. Fortunately, never having used shellac, all my glue-ups and panels have remained flat. Nyuk, nyuk.

*wormil* Thanks for the research confirming my conclusion.

Don't worry, be happy


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## wormil (Nov 19, 2011)

Posted here since this is where we talked about it the most but this is a chart from an old issue of Fine Woodworking that summarizes the PDF I linked to earlier. The higher the number, the higher the water resistance.


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## shampeon (Jun 3, 2012)

Yes, Clint. The reason your panels never warped was because you avoided shellac. It's just science.


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## JGM0658 (Aug 16, 2011)

the higher the water resistance.

Sigh,...water resistance and permeability to water vapor are different things.

Well Clint, as the saying goes. It is preferable to be lucky than smart…. ;-)


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## pintodeluxe (Sep 12, 2010)

Wow, it's as if someone said they don't like the Festool brand. This is one heated debate, considering we are talking about bug excrement.


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## wormil (Nov 19, 2011)

*Sigh,...*

Yes, I meant water vapor. No need to be snide.


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## ETwoodworks (Jan 10, 2011)

If you mix equal parts BLO/SealCoat and then apply liberaly to your project. Then throw a match at it. Will it be finished?


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