# Shellac or Poly



## ship (Mar 22, 2009)

Been years since I studied such things in school and with Shellac it would seem now a days, there ain't crushed up bugs involved with the former.

Bought some Shellac recently for a past daisy type "she loves me..." card project for the wifie. Turned out it more melted the pedals than preserved them.


So no given lots of Sellac available for her new dresser, what's the difference between it and Polyurathane in end result?


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## curtg (Mar 23, 2009)

The solvents are different. Shellac is cut with alcohol. Shellac is easier to fix.

Poly is tougher. I have read that a lot of people are using the two together (i.e., Shellac with Poly over it on the high wear surfaces).

Shellac is also used as a separator layer between various stains and toners.

I would go with shellac for my highest quality work, and poly for everyday functional pieces.

There is fine construction and then there is theatre construction.


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## Van (Mar 23, 2009)

ship said:


> Been years since I studied such things in school and with Shellac it would seem now a days, there ain't crushed up bugs involved with the former........
> So no given lots of Sellac available for her new dresser, what's the difference between it and Polyurathane in end result?


 
Yep Ship, Shellac is still made from the carapace of the Lac Beetle. 
No bugs, no Beautiful finishes. After the bugs are euthanized < Humainly, I'm sure.> they are covered in Denature alcohol and the shellac is leeched from there little beetle bodies. Check out this place Shellac.net It's hard to believe these guys are as excited about shellac as they are, but they are. < maybe too many denatured alcohol fumes....> 

Major difference between Poly and shellac is thickness of finish, resistance to nicking/scratching Water resistance, finish times, finishing process.

Shellac can be as thick as you want it, provided you put on enough coats. Poly is going to go on thicker and require fewer coats.
Shellac is more likely to crack, on it's own, when it ages though not as much as a varnish. 
Poly's are designed to not crack.
Shellac is highly water resistant provided you are using a "common" shellac not a "de-waxed" but long term exposure to water can lead to premature discoloration.
Poly is a man made product that inherently Hydrophiliac when setting up and impervious to water when cured.
High quality Poly's need hours to set up and days to cure, cheaper Poly's hours and hours.
Shellacs are absorbed into the wood, usually resulting in a natural staining process. Shellacs can be used on top of any finish and stick to almost anything. Poly's are usually used as a top coat over another staining product but shouldn't be used over certain oil-based stains and won't adhere to most plastics.


And most important 
Polyurethane should never be eaten.
Shellac < all natural> is an FDA approved food coating.


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## jonliles (Mar 23, 2009)

Why don't you try decoupage and then applying poly or even a varnish on tap of that?

If you are interested, here is the wikipedia entry:
Decoupage - Wikipedia, the free encyclopedia


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## ship (Mar 24, 2009)

Hmm, definate warnings on the can about Poly over Shellac. Still though, Varnish, Poly, 
Schellac, Tounge Oil (never found use for it in not drying) etc. Fine woodworking, not that I am above stage construction I would say at this point.. Wondering.


curtg said:


> The solvents are different. Shellac is cut with alcohol. Shellac is easier to fix.
> 
> Poly is tougher. I have read that a lot of people are using the two together (i.e., Shellac with Poly over it on the high wear surfaces).
> 
> ...


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## ship (Mar 24, 2009)

Because that's a project for another day in having personal free time and not in stock finishes. On the other hand, stuff not considered in attempting new finishes.

Hate finishing the stuff - love building the stuff. 

Why do I have it in the back of my head somewher that Shellac is more for smaller scale type special projects such as what melted the daisies in my last project?

In doing finishes, Poly no doubt is easier, but in an artistic sense what's the difference in them in doing the job but really in a some day "Norm" type of way choosing one over another given the above noted thickness and or cracking concept?

Got some oak swing arm planters to finish next, shellac, Varnish, Poly or other? Very curious in finish coatings.



jonliles said:


> Why don't you try decoupage and then applying poly or even a varnish on tap of that?
> 
> If you are interested, here is the wikipedia entry:
> Decoupage - Wikipedia, the free encyclopedia


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