# How different is shellac from flakes compared to Seal Coat in rattle can?



## Quickstep (Apr 10, 2012)

I have a project where I plan to apply a seal coat of shellac under the topcoat. I conducted a test last night using a rattle can of Zinsser Seal Coat, followed by a couple of coats of the top coat. I sprayed a quick and light coat of Seal Coat on a sample piece. It dried almost instantly and the resulting film seemed, for lack of a better term, brittle; very hard. As it turns out though, I don't want to spray the actual project, I need to wipe it, so this morning I mixed up a 1.25pound cut of Super Blonde from flakes. Once it dissolved, I wiped on a quick coat on a test piece; It took longer to dry and seems less brittle than the shellac from the rattle can. My flakes have been around for a while, so I want to make sure I'm not taking a chance, but also wondering about the properties of flakes versus rattle can.


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## mako1 (Jan 25, 2014)

I don't have much of an answer for you.Just a few thoughts as I always mix my own from flake.
The shellac in the rattle can may have been mixed thinner to allow it to atomize better from the can.
The propellant used is chemical and may have some effect on the product.
The shelf life of the can is unknown.
The can may have some additives other than shellac and alcohol.


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## Steve Neul (Sep 2, 2011)

I don't use a lot of shellac. Most shellac flakes have a natural wax which isn't suited for some finishes especially polyurethane. You can get de-waxed shellac flakes which is the same product as sealcoat. Shellac has a short shelf like once mixed so folks that use shellac normally use the flakes so they can mix it as they use it so it is fresh. I'm not sure if there is an expiration date on rattle can sealcoat or not so you just don't know how fresh it is. When shellac gets old it dries slower and just doesn't make as good of a finish as if it were fresh. If you did a project with old shellac as the final finish it would age faster and be more prone to water spot than if it were fresh. In flake form it doesn't really age. It's exposure to alcohol that screws it up.


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## HowardAcheson (Nov 25, 2011)

I'm not quite sure how to answer you on this. First, the shellac in an aerosol can is the same as flake shellac that has been mixed with denatured alcohol. The aerosol shellac is thinner (more alcohol) so that it sprays under the low pressure of a spray can. The spray can shellac is about a 1/2# cut while the shellac you mix from flakes can be any cut depending on the ratio of shellac flakes to alcohol. The aerosol can shellac is 100% dewaxed and the Zinsser Sealcoat product is a 2# cut and 100% dewaxed. Shellac is shellac. The only differences between shellacs is whether it has been dewaxed or the amount of alcohol. Of course, the alcohol quickly and completely evaporates and has not affect on the shellac itself.


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## Quickstep (Apr 10, 2012)

Wow! I didn't realize the shellac in the rattle can was such a light cut. No wonder it dries quicker than my 1.25# cut. Also see from looking at the can that is contains acetone.


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## HowardAcheson (Nov 25, 2011)

Acetone is a common thinner/solvent for shellac. The is no reason not to substitute acetone for denatured alcohol.

Sprayed shellac will appear to dry (evaporate) faster than brushed or wipe shellac. The spray process produces a very fine mist which will evaporate faster. The movement of the atomized shellac will also tend to evaporate faster.


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## epicfail48 (Mar 27, 2014)

The acetone in the spray stuff probably doesn't hurt dry time either


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## Steve Neul (Sep 2, 2011)

I bet acetone hurts the shelf life though.


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## Rick Mosher (Feb 26, 2009)

The quality of the alcohol you use is very important with the flakes. All alcohols are not the same quality. A site like Shellac.net sells a high quality alcohol as well as dewaxed flakes.


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## RandyReed (Jul 30, 2014)

I dont think there is much of a difference between the 2 *If* the cut is the same. The can uses acetone and other propellants under pressure so it can be sprayed out of a can. 

Ive never understood why so many people like using shellac. The only time I would use shellac is when I want to replace an original 19th century finish with the same thing, but there’s rarely a reason to use shellac in a factory or cabinet shop making cabinets and other objects out of new wood.

Even in doubt when refinishing old furniture and I need to use a barrier coat, I would always use a dewaxed shellac, but it is more expensive. Otherwise, a high build sealer is my go to.


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## epicfail48 (Mar 27, 2014)

RandyReed said:


> I dont think there is much of a difference between the 2 *If* the cut is the same. The can uses acetone and other propellants under pressure so it can be sprayed out of a can.
> 
> Ive never understood why so many people like using shellac. The only time I would use shellac is when I want to replace an original 19th century finish with the same thing, but there’s rarely a reason to use shellac in a factory or cabinet shop making cabinets and other objects out of new wood.
> 
> Even in doubt when refinishing old furniture and I need to use a barrier coat, I would always use a dewaxed shellac, but it is more expensive. Otherwise, a high build sealer is my go to.



Its relatively cheap, easy to use, comes in a variety of colors, dries quick, cleans easy and looks great. What's not to like? In a factory, sure, it doesn't make much sense to use it, but a factory is probably also set up to use something stronger, like a conversion varnish. For a home shop, however, shellac is awesome.

Oh, and its food safe. Kids toys and stuff like that


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## RandyReed (Jul 30, 2014)

epicfail48 said:


> Its relatively cheap, easy to use, comes in a variety of colors, dries quick, cleans easy and looks great. What's not to like? In a factory, sure, it doesn't make much sense to use it, but a factory is probably also set up to use something stronger, like a conversion varnish. For a home shop, however, shellac is awesome.
> 
> Oh, and its food safe. Kids toys and stuff like that


A can of shellac might be slightly cheaper, but you will get more build out of 1 can of sealer over 1 can of shellac. Even for a homemade shop, I would use a high build sealer over shellac any day......especially if Im gonna spray it. Unless I'm replicating an old piece, give me a nitrocellulose sealer. 

Even though shellac and wax are the only finishes I know that are "edible", all finishes are non-toxic when fully cured, despite what you may have read or heard. Once the solvents are evaporated, the cured film is safe enough for contact with food. This does not mean that the finish itself is safe to gobble up. It means that additives such as driers or plasticizers are encapsulated enough so that they do not migrate to what you’re eating. 

Most finishes are considered kid safe now a days.


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## Al B Thayer (Dec 10, 2011)

epicfail48 said:


> Its relatively cheap, easy to use, comes in a variety of colors, dries quick, cleans easy and looks great. What's not to like? In a factory, sure, it doesn't make much sense to use it, but a factory is probably also set up to use something stronger, like a conversion varnish. For a home shop, however, shellac is awesome.
> 
> Oh, and its food safe. Kids toys and stuff like that


Reese's Pieces are coated with shellac. 

Al


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## epicfail48 (Mar 27, 2014)

RandyReed said:


> A can of shellac might be slightly cheaper, but you will get more build out of 1 can of sealer over 1 can of shellac. Even for a homemade shop, I would use a high build sealer over shellac any day......especially if Im gonna spray it. Unless I'm replicating an old piece, give me a nitrocellulose sealer.
> 
> Even though shellac and wax are the only finishes I know that are "edible", all finishes are non-toxic when fully cured, despite what you may have read or heard. Once the solvents are evaporated, the cured film is safe enough for contact with food. This does not mean that the finish itself is safe to gobble up. It means that additives such as driers or plasticizers are encapsulated enough so that they do not migrate to what you’re eating.
> 
> Most finishes are considered kid safe now a days.


Safe once cured, unless you happen to swallow a chip. Im also no debating the use of shellac as a sealer, i have no doubt a uni-purpose sealer would probably work better. My argument is for shellac as a finish


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## RandyReed (Jul 30, 2014)

epicfail48 said:


> Safe once cured, unless you happen to swallow a chip. Im also no debating the use of shellac as a sealer, i have no doubt a uni-purpose sealer would probably work better. My argument is for shellac as a finish


No debate from me either, I was just wondering why people would use shellac instead of a sealer if they are not reproducing an older piece. 

I also hope no one is eating wood chips no matter what finish is on it! HAHA.


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## Al B Thayer (Dec 10, 2011)

RandyReed said:


> No debate from me either, I was just wondering why people would use shellac instead of a sealer if they are not reproducing an older piece.
> 
> I also hope no one is eating wood chips no matter what finish is on it! HAHA.


I use Mohawk finishes when spraying. I use there sealer.

If I'm building furniture, 99% of my work, I use "wipe on anything except poly". I own one paint brush and almost never use it. I use shellac when I French polish. It's an absolute pleasure. On coffee tables, end tables, glove tables, and any fine furniture. It's very easy to repair and recoat if needed. Always get great results. That's why I use it.

Al


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## Quickstep (Apr 10, 2012)

My case for shellac:

To my eye, shellac, when used as a sealer or topcoat makes for a warmer color than lacquer. I'm not sure, but I don't think you can (easily) wipe or brush lacquer. As an added bonus, brushes used for shellac don't need to be cleaned; just let them harden and re-dissolve before the next use. Shellac made with good alcohol and good flakes is more durable than you think. I have a handrail and a banjo done in shellac and they still look good. My favorite finish is a couple of coats of shellac followed by wax applied with 0000 steel wool. Not incredible protection, but it looks awesome and _feels_ even better. My last thought is really my first reason for using shellac. Nitro Lacquer is nasty, nasty stuff; shellac - ..........no so much.


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## RandyReed (Jul 30, 2014)

Quickstep said:


> My case for shellac:
> 
> To my eye, shellac, when used as a sealer or topcoat makes for a warmer color than lacquer. I'm not sure, but I don't think you can (easily) wipe or brush lacquer. As an added bonus, brushes used for shellac don't need to be cleaned; just let them harden and re-dissolve before the next use. Shellac made with good alcohol and good flakes is more durable than you think. I have a handrail and a banjo done in shellac and they still look good. My favorite finish is a couple of coats of shellac followed by wax applied with 0000 steel wool. Not incredible protection, but it looks awesome and _feels_ even better. My last thought is really my first reason for using shellac. Nitro Lacquer is nasty, nasty stuff; shellac - ..........no so much.


I understand Quickstep.

I guess I just trained myself over time to find the easiest way to finish pieces. Even now when I do older pieces, I came up with an amber tinted lacquer that I can use in certain instances under my final coat of lacquer in place of shellac to replicate older pieces. I spray everything I can and try to stay away from brushing and wiping unless I absolutely have too. Over the years I have got real good at matching colors with dyes and wipe stains, I dont need to use shellac anymore. I have even come up with my own fumed formulas for oak, so no need to use ammonia anymore for me either, LOL. I guess it just boils down to what I am trying to reproduce as to what technique I will use.

Al, I am also against "anything poly".


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## Al B Thayer (Dec 10, 2011)

Easy Warm Foolproof. 









I know, it's not Tung oil. But it's a beautiful finish and tough enough for anything but a bowling ally.











Don't know if they make this anymore but I like this one too. On furniture I do 5 to 6 coats and never follow the directions on the can.

Al


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## Quickstep (Apr 10, 2012)

Al,

If you like that, you might want to try Waterlox. The oil in Waterlox _is_ tung oil. I use Waterlox original which has the lowest resin content. The resin content really is just a function of how quickly it builds gloss. I actually like that because you can build gloss gradually and stop when you like what you see. One or two coats for matte, two or three or four for semi gloss and four or five for gloss.


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## Al B Thayer (Dec 10, 2011)

Quickstep said:


> Al,
> 
> If you like that, you might want to try Waterlox. The oil in Waterlox is tung oil. I use Waterlox original which has the lowest resin content. The resin content really is just a function of how quickly it builds gloss. I actually like that because you can build gloss gradually and stop when you like what you see. One or two coats for matte, two or three or four for semi gloss and four or five for gloss.


You know I've never heard a bad word about Waterlox finishes. I've put it on my list of gota try it finishes. Thanks for the thumbs up your one of many that back the product.

Al


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