Tom LaRussa
02-19-2005, 11:54 PM
I use a variant of the old-fashioned recipe that floats around all the boards.
Basically, it's a mixture of
BLO
Turpentine
Powdered Asphaltum
Powdered Rosin
Damar Gum
I got the asphaltum from http://www.rembrandtgraphicarts.com (http://www.rembrandtgraphicarts.com/)
The rosin & Damar gum are from http://www.dickblick.com (http://www.dickblick.com/)
Making the Japan
The exact proportions really don't matter much, in my experience, but I'd say that the dry ingredients are proportioned roughly like so:
5 asphaltum
3 rosin
1 Damar
The wet ingredients are probably about 60% BLO & 40% turpentine.
I mix wet and dry to about the consistency of 50 wt motor oil.
I heat it in a double boiler until the mixture no longer feels grainy between my fingers.
Note that I do this outdoors on my propane-fired turkey fryer. If there is no breeze I set up a fan to blow across the fryer to keep the fumes from accumulating near it or ME. I always wear safety goggles and welder's gloves when doing this, and keep a fire extinguisher handy.
I use a three pound coffee can filled with water as a pot and a smaller can for the insert. I use a spring clamp to hold the small can against the side of the large one.
Painting:
I paint it on in very thin layers -- thin enough so that the metal shows through most of the first one.
Preheating the part until it is almost too hot to touch seems to speed things up a bit -- I think by causing the turpentine to evaporate as the Japan is going on the part.
I bake each layer at 450F for an hour or two. You know it's ready to come out when it no longer leaves residue when rubbed with a scrap of wood. I like to put the successive layers on while it's still hot, but it's not a necessity.
The only bummer to this method is that it discolors the metal, so I have to rebuff the exposed parts of the entire plane.
Note regarding bench planes.
Having to rebuff the exposed iron was really driving me nuts with bench planes because I'd try to rebuff the froggie seat with a roto-tool, and invariably I'd touch the tool to some Japanned part, ruining the entire thing.
Now I just hit the frog with a 3M pad, by hand. It doesn't get rid of all the discoloration but it's better than spending the rest of my life perpetually japanning the same piece.
Basically, it's a mixture of
BLO
Turpentine
Powdered Asphaltum
Powdered Rosin
Damar Gum
I got the asphaltum from http://www.rembrandtgraphicarts.com (http://www.rembrandtgraphicarts.com/)
The rosin & Damar gum are from http://www.dickblick.com (http://www.dickblick.com/)
Making the Japan
The exact proportions really don't matter much, in my experience, but I'd say that the dry ingredients are proportioned roughly like so:
5 asphaltum
3 rosin
1 Damar
The wet ingredients are probably about 60% BLO & 40% turpentine.
I mix wet and dry to about the consistency of 50 wt motor oil.
I heat it in a double boiler until the mixture no longer feels grainy between my fingers.
Note that I do this outdoors on my propane-fired turkey fryer. If there is no breeze I set up a fan to blow across the fryer to keep the fumes from accumulating near it or ME. I always wear safety goggles and welder's gloves when doing this, and keep a fire extinguisher handy.
I use a three pound coffee can filled with water as a pot and a smaller can for the insert. I use a spring clamp to hold the small can against the side of the large one.
Painting:
I paint it on in very thin layers -- thin enough so that the metal shows through most of the first one.
Preheating the part until it is almost too hot to touch seems to speed things up a bit -- I think by causing the turpentine to evaporate as the Japan is going on the part.
I bake each layer at 450F for an hour or two. You know it's ready to come out when it no longer leaves residue when rubbed with a scrap of wood. I like to put the successive layers on while it's still hot, but it's not a necessity.
The only bummer to this method is that it discolors the metal, so I have to rebuff the exposed parts of the entire plane.
Note regarding bench planes.
Having to rebuff the exposed iron was really driving me nuts with bench planes because I'd try to rebuff the froggie seat with a roto-tool, and invariably I'd touch the tool to some Japanned part, ruining the entire thing.
Now I just hit the frog with a 3M pad, by hand. It doesn't get rid of all the discoloration but it's better than spending the rest of my life perpetually japanning the same piece.