Primitive Archer

Main Discussion Area => Bows => Topic started by: DC on July 25, 2019, 10:12:58 pm

Title: Shellac first coat
Post by: DC on July 25, 2019, 10:12:58 pm
I've read that shellac makes a good first coat for just about any finish. If I apply 'tung" oil according to the instructions it sounds like it soaks into the wood somewhat which seems like a good thing. If I was to put a coat of shellac on first wouldn't it stop the oil from soaking in?
Title: Re: Shellac first coat
Post by: Selfbowman on July 25, 2019, 10:17:11 pm
Don’t know. But I think probably so. Arvin
Title: Re: Shellac first coat
Post by: Pat B on July 25, 2019, 10:29:07 pm
Yes it would. It is a good sealer over crayon drawings on the wall, grease spots, etc. so it will prevent the tung oil from penetrating.
Title: Re: Shellac first coat
Post by: slowbowjoe on July 25, 2019, 11:08:57 pm
What Pat said.
Title: Re: Shellac first coat
Post by: DC on July 26, 2019, 02:11:01 am
Yes it would. It is a good sealer over crayon drawings on the wall, grease spots, etc. so it will prevent the tung oil from penetrating.
Now, is that necessarily a bad thing? Is the tung oil going to peel off, chip or otherwise fail? Is there a good/any reason for putting shellac on first? Unless your kids crayoned it ;D ;D
Title: Re: Shellac first coat
Post by: Eric Krewson on July 26, 2019, 10:19:17 am
Shellac is a poor finish for anything that may be out in the weather, it is not waterproof in the least and will absorb water and turn white.

Why use it in the first place, there are so many much better finishes out there.
Title: Re: Shellac first coat
Post by: Marc St Louis on July 26, 2019, 10:57:58 am
Shellac doesn't  repel water all that well, it takes several hours for water to work it's way through, but apparently it is a fairly good moisture repellent.
Title: Re: Shellac first coat
Post by: Sidmand on July 26, 2019, 12:35:33 pm
I use tung oil for lots of stuff, and it is a really good sealer in and of itself.  I use several thin coats, letting it dry well in between each coat, and on the final coats I use some 0000 steel wool to buff the finish a little before the next.  You can get a glossy glassy finish that way, and it seems to be water repellent after it drys.  Does take a while to dry though, especially in high humidity (central alabama).  I don't think shellac would help it, and if shellac is on there first you don't get the penetrating benefits of the tung oil - I don't know if it would peel but it would not help the wood any which is why I use it.

You can buy food safe tung oil that you can use on wooden bowls and utensils too.
Title: Re: Shellac first coat
Post by: DC on July 26, 2019, 12:43:38 pm
I won't use it then. I use it for sealing staves and it seems great for that but I've often wondered how well I can remove it from the back when I'm ready to oil. I use lacquer thinner and/or alcohol to get it off but I've often thought that I'm just thinning it so it can soak in deeper.
Title: Re: Shellac first coat
Post by: wizardgoat on July 26, 2019, 01:28:54 pm
I like to use homemade  shellac for a first coat on yew bows. I really like how it makes the grain pops, I can see missed tool marks and it dries super fast.
I then use tung oil on top. It takes around 5 coats to get a good shell. Without shellac, it seems to take me around 8 coats or more to get a good shell.
This proves to me shellac does prevent some oil from soaking into the bow, but how much? Whenever I’ve reworked older bows it seems like a couple scrapes and I’m back into fresh wood.
Title: Re: Shellac first coat
Post by: bassman on July 26, 2019, 08:10:11 pm
I use shellac on some bows. Up to 6 coats, and then soft bee,s wax over top .
Title: Re: Shellac first coat
Post by: willie on July 26, 2019, 08:28:38 pm
I like tung better than shellac for a finish, but shellac does have its uses.
shellac is useful as fast drying somewhat non-toxic finish. I would rather have wood alcohol on my skin rather than lacquer thinner or other volatile hydrocarbons.
the shellac itself can often serve as a barrier coat when applying a finish over another finish, when the base finish and the top finish have reaction problems. generally one tries to avoid using reactive finishes, but shellac has saved the day for me when nothing else worked.