Alternative to Dewaxed shellac?

Tom Baugues

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I have some exotic hardwoods here (bloodwood, purplehart, padauk, redhart) that I want to use on some small projects. I've read that they should be sealed with dewaxed shellac first then can be coated with either water or oil based polyurethane to bring out and try to preserve the color.
The product I'm looking at is Seal Coat by Zinsser. Problem is.....I've been to Menards, Home Depot and Lowes here locally but none of them carry it. Home Depot did have a gallon can of it but I certainly don't need that much. So my question is....what do I use on these woods to seal them so I can apply a clear finish? Is dewaxed shellac the only thing I should use of these woods? I don't want to get into mixing up my own shellac.
 
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I have some exotic hardwoods here (bloodwood, purplehart, padauk, redhart) that I want to use on some small projects. I've read that they should be sealed with dewaxed shellac first then can be coated with either water or oil based polyurethane to bring out and try to preserve the color.
The product I'm looking at is Seal Coat by Zinsser. Problem is.....I've been to Menards, Home Depot and Lowes here locally but none of them carry it. Home Depot did have a gallon can of it but I certainly don't need that much. So my question is....what do I use on these woods to seal them so I can apply a clear finish? Is dewaxed shellac the only thing I should use of these woods? I don't want to get into mixing up my own shellac.

I had good luck finding the seal coat at a local Ace hardware.
 
"I don't want to get into mixing up my own shellac."

Why not? Its not hard. Its cheaper. You make only what you need. It just takes some time and some planning. My friend Micheal Dresdner showed me how years ago but I haven't needed to for years. He allowed lots of time for initial soaking and then ritual shaking until all was in solution. Probably s bunch of guys here who know how. And keep the flakes dry between uses.
 
"I don't want to get into mixing up my own shellac."

Why not? Its not hard. Its cheaper. You make only what you need. It just takes some time and some planning. My friend Micheal Dresdner showed me how years ago but I haven't needed to for years. He allowed lots of time for initial soaking and then ritual shaking until all was in solution. Probably s bunch of guys here who know how. And keep the flakes dry between uses.

So would someone like to explain to me how to mix my own de waxed shellac. I'll have to start searching for it.
 
I feel that the extended shelf life of the Zinsser products make then a good value but, I use a fair amount of shellac. Not a lot but, probably more than many one man Garage-Mahal woodworkers do. If you want to mix your own, here's a place to look. I'm sure there are others that folks will recommend: http://www.shellac.net/dewaxed_shellac.html
 
So would someone like to explain to me how to mix my own de waxed shellac. I'll have to start searching for it.

I am really surprised that there is no Zinsser Sealcoat around there - it may not say shellac in obvious letters but its basically low cut dewaxed shellac with some stabilizers added. The stabilizers actually make it not to bad of a deal for folks who are only intermittent users as it does last a lot better than homemixed stuff (once mixed).

But anyway... don't let all this overwhelm you - basically you take flakes, mix with good quality high proof, mix well and use. The rest is fluff.

Step one acquire shellac:

Step two acquire high proof ethanol
  • DNA from the hardware store works as long as its actually high proof alcohol (85% or better) you can
  • The shellac.net place lists some types known to be good and also sells some (http://www.shellac.net/alcohol.html) - I've seen the Klean Strip stuff local, but Joel at TFWW doesn't like it: https://www.toolsforworkingwood.com...MSDS Sheets and Why You Should Look Them Over.) - personally I think Joels doing a bit of selling there on the over 190 proof bit but his point about methanol in the SLX is reasonably well taken.
  • Everclear or other 190 proof grain alcohol is similar although more expensive but it doesn't have any denaturing agents DNA has (which some people prefer to avoid)
  • I use mostly the heads and tails from a friends purification process that aren't fit for drinking ;) Stephen Sheppard agrees: http://www.fullchisel.com/blog/?p=1401


Step three mix
The mix is in "lbs per gallon" but you will obviously want to scale that down a lot. Make up an ounce or three at a time is usually around the right amount. For most seal coat work a 1/4-1/2lb "cut" (equivalent of 0.25-0.5lb/gallon) is pretty good, I generally find the thinner stuff easier to work with in general and cut back the seal coat stuff even when I use it.

Mix chart here: http://www.shellac.net/PoundCutChart.html

Small glass jars with tight sealing lids work well for this as do small empty paint cans. The container should be just a wee bit bigger than your batch.

Stir/shake vigorously and let the mix sit overnight and then stir/shake vigorously again.

If its not dewaxed you can let it set for a couple of days and then pour the shellac off of most of the wax. Some shellac's aren't very clean so you may also want to pour it through some cheese cloth or even a coffee filter (that can be sloooooow/impractical at higher cuts). Stephen Shepards blog has a nice example of how to make shellac from seed lac - which is uncleaned shellac: http://www.fullchisel.com/blog/?p=232 - he also doesn't worry about the wax: http://www.fullchisel.com/blog/?p=39 but acknowledges that it interferes with a lot of modern finishes.

If the flakes don't dissolve one of two things went wrong: either your alcohol wasn't pure enough (common) or the shellac is to old - air/heat/moisture are all the enemies of shellac in storage so store well sealed in a dry/cool place.

Joel at TFWW has a couple of good articles on the process:
https://www.toolsforworkingwood.com...rove The Shelf Life of Dewaxed Shellac Flakes
https://www.toolsforworkingwood.com...hanol, Isopropal, Water, and French Polishing
https://www.toolsforworkingwood.com/store/blog/363/Shellac Shelf Life -The Followup

Some history:
https://www.toolsforworkingwood.com/store/blog/163/Getting Sh..
https://www.toolsforworkingwood.com/store/blog/165/title/Getting Shellaced - part 2
 
To clarify, I CAN find Zinsser shellac in both clear and amber. What I cannot find is the "Seal Coat" by Zinsser (which is the dewaxed shellac). At least not at the big three stores I went to today. Home depot had a gallon can of it but at $38.00 I passed on it. I'll go to a couple other places tomorrow.
 
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To clarify, I CAN find Zinsser shellac in both clear and amber. What I cannot find is the "Seal Coat" by Zinsser (which is the dewaxed shellac). At least not at the big three stores I went to today. Home depot had a gallon can of it but at $38.00 I passed on it. I'll go a couple other places tomorrow.

Weird!

It would also be worth while to note that the clear in the spray can is dewaxed even though it doesn't actually state it anywhere obvious - this stuff:
http://www.rockler.com/zinsser-clear-spray-shellac

Its not as cost effective but it is fairly easy to apply. In general the thinner the shellac coat the happier you'll be in my experiences, of course I'm doing almost entirely wipe on so YMMV.
 
Now, the spray cans I DID see at the stores. However since I was looking for the "Seal Coat" I didn't consider them.

I looked up the store I got the Seal Coat at last, and it was a True Value, granted it's one of the largest and oldest around here, but they carried it along with a few other brands I couldn't find at the box stores. Lowes used to carry it, but the manager said they just didn't sell enough of it to keep it in stock.
 
Odd, I picked up my last quart can of Seal Coat at Menard's. I'll have to look again when I'm there today. Could it be they were just out of stock when you were there?

Update, I did get to Menard's this morning and they seem to have quit carrying the Seal Coat. Unless Zinnsser stopped making it.
 
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I have found that seal coat is not a commonly stocked item at most stores. I found mine at a dedicated paint store. One thing I will mention is after opening the can the first time is do not close it backup and put on the shelf. The alcohol (or something else) has a detrimental effect on the can and it will begin to spring leaks in short order. Best to pour your remaining seal coat in a glass container or you will find it one day glued to the shelf with the dried shellac (personnel experience).
 
I have found that seal coat is not a commonly stocked item at most stores. I found mine at a dedicated paint store. One thing I will mention is after opening the can the first time is do not close it backup and put on the shelf. The alcohol (or something else) has a detrimental effect on the can and it will begin to spring leaks in short order. Best to pour your remaining seal coat in a glass container or you will find it one day glued to the shelf with the dried shellac (personnel experience).

Robert is correct about the water in the DNA but, you don't have to open the cans ;-). Zinsser has replaced a couple of cans for me that I stored for too long even unopened. Now I just transfer the material to plastic or glass without issue.
 
Zinsser shellac is normally 3 pound cut. The blonde shellac is often dewaxed or at least low wax. But it means when you buy a quart you are getting close to a gallon after dilution with alcohol.

Zinsser seal coat is a 2 pound cut of blonde dewaxed shellac. Less alcohol required. Even though you only get 2/3 as much actual shellac, it is often more expensive.

For the last couple years Zinsser has been adding a little acid to the shellac and seal coat to extend the shelf life. However, the acid interferes with water base finishes. I use very thin coats of Zinsser and haven't had a problem (yet), but some of my friends (pros) have had enough problem that they have gone to mixing their own shellac.

Shellac is very good at popping the color of exotic wood (including Walnut). Target EM1000 sanding sealer does an identical job of popping the color (in my tests), so I usually just use the Target sealer.
 
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