French Polish Tutorial Part 1.
Ok, so French Polish is a technique for applying finish. While there are a few options for finishes that can be applied that way, I'm using shellac.
Materials:
Danish oil
Shellac flake
Ethanol
Olive oil
Ground pumice stone
Cotton balls
Cotton fabric (old t-shirts)
400 and 800 grit wet/dry sandpaper
I mixed up a 2lb cut of very light blonde shellac. This means 2 lbs of shellac flake dissolved in 1 gallon of alcohol. I mixed up only 16 oz/0.5 L so I used only 53 g of shellac flake for this.
First I applied Danish oil. I did this as one flood coat and a second where I used 400 grit wet/dry sandpaper to wet sand the surface. While this made the surface smoother, part of the idea was to partially fill the pores. I don't believe this really did much if anything to fill the pores.
I then let this dry for 72 hours as per Watco's directions. At this point I applied a flood coat of shellac. The purpose of this coat is to lay down enough shellac for pore filling. I just applied it with some folded cotton fabric.
Pore filling is done by using a fresh pad made up of cotton balls inside of a cotton fabric pouch made with a piece of fabric and held into a ball with an elastic band. Only alcohol is applied to the pad along with a very small amount of pumice. This is rubbed on the shellac and causes the shellac to partially dissolve and then this along with the sanding action of the pumice stone creates a wood fibre/pumice/shellac slurry that fills the pores. This process is done over the open pored wood - in this case it is the walnut, Bloodwood and mahogany. Three sessions over the entire surface got me to where I was happy with the filling of the pores.
Here's a couple of shots of pore filling:
Open pores in walnut:
Surface after one of the sessions:
Trying to show the change to the surface:
I think this shows pores being filled:
Once this is done I move on to the "bodying" sessions. This is building up the shellac finish and hopefully doing it while keeping it level. For this a new pad is made the same as before but the cotton ball centre is soaked with 2lb cut shellac. About 6 drops of alcohol are added to this followed by one drop of olive oil. I tap this on the back of my hand to spread the oil over the pad. This is then rubbed on the surface in small circles and quickly enough to keep the pad from sticking. You can see the finish get cloudy where the fresh shellac is being applied and it dries back to clear rather quickly. I do one surface entirely before moving on to the next (back, sides and top). As the pad dries/runs out of finish, I add more shellac, alcohol and oil to the pad and keep going. I do this three times before "stiffing". Stiffing is applying only alcohol to the pad and running it in long strokes over the finish. This does two things - removes the olive oil and levels the finish a little bit. Once this is done I let the finish dry 2-3 hours before another session.
This is where I'm at now - 2 bodying sessions complete. I'll do a few more before I wet sand the shellac flat and continue building up the finish prior to the final polishing.