Replies

1. 
   VeniciaL | Dec 20, 2003 03:23am | #1

   JSCW,

   No, you should not seal rosewood, or any wood before applying an oil finish. Oil finishes need to penetrate the wood and harden (polymerize) within the tiny bit of penetration they achieve. Film finishes such as varnishes or laquers harden on top of the wood with very little penetration.

   It sounds like the finish you applied has not penetrated much, or you have not wiped the excess off the surface as needs to be done with an oil finish. Some tung oil finishes are not adequately heat activated (partially polymerized) as supplied and some linssed oil preparations don't have sufficient metalic driers in them to harden rapidly. These oils will sit on a non pourous surface for weeks still "wet." It sounds like that is happening with your finish.

   All that said, the rosewoods are amoung the most disappointing woods to try and finish with oil. They have a waxy surface that defeats the effort. Especially cocobolo, but I've had problems with other rosewood species as as well. These woods finish beautifully with lacquer - either spraying or wiping.

   Also, sanding to 400 - 600 grit and just applying paste wax works very well.

   Try wiping down your unhardened finish well with a rag damp with mineral spirits or naphtha. Then let it sit for about a week. If it's not hardened by then, sand to fresh wood and try lacquer.

   VL

2. 
   Floss | Dec 20, 2003 07:23am | #2

   Jonathan,

   Usually oily woods, cocobolo/rosewood, are best finished or glued up after they have been stripped of their natural oils. Acetone workes well for this. You can probably remove any applied oil with thinner and then follow with acetone and re-apply the oil with better success. Then you can topcoat with your choice of finish.

   J.P.

1. 
   WorkshopJon | Dec 21, 2003 11:47pm | #3

   "Usually oily woods, cocobolo/rosewood, are best finished or glued up after they have been stripped of their natural oils. Acetone workes well for this."

   JP,

   Good tip.

   Here's another (though not EPA, nor FDNY approved) Instead of wiping down the project with a rag, Fill your spraygun with acetone, jack the PSI's up to ~90 to ~175, and over a tub "pressure wash" your work, then wipe it down.

   Trust me, it work's.

   Jon

3. 
   Paul_Snyder | Dec 22, 2003 07:23am | #4

   Jonathan,

   It won't cure. Strip & start over.

   To seal the chemicals in the rosewood that interfere with the oil-base finish curing, use a coat of shellac before the Daly's ProFin. Since the Daly's is a wiping polyurtehane, make sure the shellac is dewaxed so the poly will adhere well. Zinsser makes a "Seal Coat" shellac that comes dewaxed; their other shellac products (Bullseye) DO contain wax.

   Apply a coat of shellac and let dry. Sand smooth with 320 grit. Apply a second coat after two hours if you want to. Let the shellac dry overnight, sand lightly with 320 grit, and then apply the poly coats.

   Paul

1. 
   JSCW | Dec 22, 2003 10:27am | #5

   Thanks to all for the feedback.  I learned a valuable lesson, to research new woods before finishing.  I'm going to strip and start over. 

   Forunately, only one of the trays I made was made out of the Indian Rosewood, which was the prototype for the other 6.  The rest were made from Quina, which I cannot recommend enough.  A wonderful wood to work with from start to finish.

   Thanks again

   Jonathan