Replies

1. 
   saschafer | Apr 04, 2008 07:42pm | #1

   Yes, shellac over a drying oil (as opposed to, say, mineral oil) works fine, and is a standard technique.

   But test it first to make sure it looks the way you want it to!

   -Steve

    

1. 
   clutions | Apr 04, 2008 07:54pm | #2

   Thanks Steve!  I thought someone would say that ... "make sure it looks the way you want it to" ...

   Not 10 seconds after I made the post I opened an old FWW that had an article on finishes and (guess what) they were using Boiled Linseed under an amber Shellac ... go figure.

   Hope I didn't waste your time.

1. 
   Glaucon | Apr 04, 2008 09:15pm | #3

   As you point out, shellac is often applied over BLO. In fact, this is one component of French polishing.Glaucon

   If you don't think too good, then don't think too much...

1. 
   BG | Apr 05, 2008 06:15pm | #7

   Glaucon,
   Okay, without stealing the original message too much, I just finished doing a French Polish on a piece of mahogany and would now like to do it on a table top (card table). I re-finished the card table about 25 years ago with tung oil...took about 10 years to dry. If i clean it well, do you think the shellac will behave over tung oil the same way as
   BLO? thanks

1. 
   Rich14 | Apr 05, 2008 06:32pm | #8

   BG,Shellac will be fine over tung oil.Tung oil can take very, very long to polymerize if it hasn't been heat-activated before use. I've seen some that took even longer than 10 years.The same general advice applies - scrub the surface well with mineral spirits. After scrubbing you may want to "freshen" the oiled look with either a new tung oil application (use the heat activated or partially polymerized variety) or BLO. After cleaning, shellac will adhere without a problem to either the cleaned wood or a new oil application.Rich

2. 
   chaim | Apr 05, 2008 09:45pm | #9

   What is heat activated tung oil? and what do you say to walnut oil? as a few years ago I finished a piece with it and have yet to apply a top coat. the piece just collects dust in a corner for now but I'm finally willing to do something about closure as I have too many pieces half finished!

   ChaimMake your own mistakes not someone elses, this is a good way to be original !

3. 
   Rich14 | Apr 06, 2008 03:42pm | #12

   chaim,Tung oil cures by polymerization. It will do that on exposure to air but it takes a VERY long time for a thin wiped-on finish (years). Tung oil meant for wood finishing is heated to initiate the polymerization process. Heat activated tung oil completes polymerizing on the wood in weeks or months.There are various brands which advertise several different levels of heat treatment. Just Google tung oil and you'll get all the info you need.http://www.mazzonetruevalue.com/why.php?gclid=CICa8a-4xpICFQtFgQodam-quA Linseed oil and varnishes respond to metallic "driers" which catalyze their hardening (polymerization). Tung oil does not respond metallic compounds. But since many commercial preparations claiming to be tung oil actually have some linseed in them (or have nothing but linseed!) they are accelerated by driers.As for the walnut oiled piece, just wipe it clean with mineral spirits and apply shellac. Should be no problem at all.Rich

   Edited 4/6/2008 8:45 am ET by Rich14

4. 
   chaim | Apr 06, 2008 08:16pm | #15

   Thankyou for all the good info I'm sure I'll put it to good use!

   ChaimMake your own mistakes not someone elses, this is a good way to be original !

2. 
   HowardAcheson | Apr 04, 2008 11:31pm | #4

   Let's back up a second. While shellac can be applied over BLO, it shouldn't be assumed that it will work perfectly over old BLO that may have had lots of other things done to it over the years.

   Shellac sticks to almost everything--even peanut butter an old time finisher used to claim. But, I would still clean the surface before applying the shellac. Wipe it down with a rag wetted with mineral spirits and then wipe it dry with lots of paper towels. If the gunk is heavy use a gray Scotch Brite pad wetted with the mineral spirits.

   When you have it clean, then apply the shellac.

   Howie.........
1. 
   clutions | Apr 04, 2008 11:44pm | #5

   Thanks Howie ...

   I've already done that ... (I love MS.) ... When I want to get an idea of how the 'finished product' will look I put some MS on the piece. Gives a good 'picture' of how it will look after a coat of shellac is applied.

   But, thanks a lot for the heads up!

1. 
   Rich14 | Apr 05, 2008 04:08pm | #6

   And, since you like the look of the oiled wood - after thoroughly scrubbing down that old BLO surface with mineral spirits - give the piece a fresh application of BLO before finishing with shellac.Rich

1. 
   clutions | Apr 06, 2008 04:09am | #10

   How long before I can Shellac the piece after a new coat of BLO?

1. 
   saschafer | Apr 06, 2008 04:34am | #11

   How long does it take you to open the can? Traditionally, you would wait a day or more, but you can get away with applying the shellac as soon as you've wiped off the excess oil.

   -Steve

    

2. 
   Rich14 | Apr 06, 2008 03:46pm | #13

   What Steve said.Rich

3. 
   clutions | Apr 06, 2008 07:15pm | #14

   Actually, to ALL!

   Thanks for all the input ... I guess you'd probably call me a 'newbie' since I've really only been doing this wood thing since I be came retarded ... errr retired ... about 4 years.  I've really relied on FWW for alot of fine (no pun intended) information.  My skills are developing as well as my shop ... but I'm sure I still have a long way to go.

   Thanks again!!!

   Francis  aka-clutions