What is that stuff, japanning?
One of the great things about collecting is finding ways to fund it. If you've hung around this site much you know that I will frequently re-commission and resell old derelict planes previously destined for parting out, scrap, or landfill. It gives me a great deal of personal satisfaction to have developed a bit of skill at doing this as I've never really been good at producing things with my very own hands and have always envied those who can sit back at the end of the day and actually see the fruits of their labors. Restoring and selling them to craftsmen/craftswomen also gets these wonderful old relics back into the hands of people who appreciate the value and history associated with a 100 year old tool that can and will go on to produce a whole lot more cool things.
There are a lot of folks that do this and more than a few sell on eBay or elsewhere and each has their own practice and philosophy of restoration. As I've written in previous articles, I like to maintain the integrity, history and feel of the original plane, at least as much as possible, given its condition when I get it. I'll fix a broken tote and though rusty or pitted, will try to use the original parts. If I can't save the part I make every attempt to replace it with one of similar type or at least time period. It's just the way I do it and I think most of my buyers like it that way.
Sometimes I will encounter a real challenge. A plane that's been sitting in an open barn or shed, neglected and unprotected can have some real problems, most of which can be resolved with some Evaporust,, electrolysis, steel wool and WD40 or a great product called KanoKroil. Any of the process used to remove rust has a tendency to remove the crud under the old japan varnish or, on the later planes, the enamel. If the plane is sound otherwise it's always feasible to repaint using modern enamels and I've had good success with that process. Sometimes though the plane is an old classic early type, not necessarily valuable, but could be a good user, just pretty ugly.
While learning about restorations I became curious about the stuff that Stanley and others used on the finished surfaces of the main casting and frog, ie japan varnish. I discovered that it's mostly an artist application but is also used to protect metal surfaces or any surface from the deleterious affects of moisture and chemicals. In fact Ford Motor Company used it as a finish on their automobiles in the early 20th Century. At the basic level it is a mixture of linseed oil, turpentine, and a powdered or crystaline form of a specific type of asphalt product called Gilsonite. There are as many recipes for japanning as there are for Grama's choklit chip cookies but those three ingredients are included in most of them and those alone will work, if you have the time. I got my Gilsonite on eBay for about a 20 bucks a pound, it's a lot but it never goes bad as long as you keep it in an air tight container. Here's the eBay link: www.ebay.com/itm/Gilsonite-Asphaltum-200-Mesh-Powder-One-Pound-/311672376313?hash=item48911f0bf9:m:mHBsiwpGNk8kNK8mQJDDj_Q . You can also google it and see what pops up.
Recipes vary but generally follow this ratio:
Cold Mix Japanning Recipe: Add 2 parts linseed oil, 4 parts turpentine, and 4 parts asphaltum powder to your glass jar jar. ... Stir the mixture a bit and cover. Dissolve for 1-3 days. ... You may still have a bit of asphaltum on the jar's bottom that doesn't dissolve. ... Test the mixture's thickness. I've found that the longer the stuff sits, the smoother it becomes to a point, as the asphaltum dissolves in the mixture.
There is also a premixed product called "Old Pontypool" produced and sold by a small manufacturer, (Liberty on the Hudson). I've never used the product myself but understand from others that it is the real deal and works well. The product is rather expensive and the smallest size you can get is a quart, more than you'll use in a lifetime of refinishing planes ( unless your name is Stanley) and it does have a shelf life. Here is the link: http://libertyonthehudson.com/pontypool.html)
Some folks like to bake the finish after each coat and I've tried that too. I use an old roaster, you know, the kind that's big, white, with a removable top, like they used at the cafeteria in junior high. Don't grab your spouse's favorite toaster oven or that big one in the kitchen unless you like to eat your japanning with cast iron garnish. It smells a bit and I doubt that it will do your kitchen much good or your guests at the next dinner party. I got mine for 20 bucks at the local thrift store. Put the plane in a cool oven and let it heat up as well as cool down with the oven...usually about 300-350 degrees for an hour and a half or so. As the stuff dries it creates a noxious smell and some smoke. Probably not too much of a health hazard if done properly in a WELL VENTILATED AREA, like outside. Use common sense when doing this, like don't use too much heat, don't touch hot iron with a bare hand, be careful and turn your head away when removing the top from the oven as the fumes may obnox you.
Some folks reheat a second time, at a higher/lower temperature to help the stuff cure. I have recently had better luck just cooking it once after each coat. It speeds up the process a quite bit and Ive used it more of late. Honestly, I had poor results early on with the japan bubbling up when it cooled but lately, it has been working well and the finish is quite smooth, almost "buttery" looking. I used to go low heat, like 250 -275 degrees F. and the change occurred when I started going with the higher 350 temperature. Not sure if it's the temperature or mixture age that has improved my results, but yours may vary.
My results have been mixed and I've modified the ratios and experimented on a number of projects, with limited satisfaction early on. Cold curing takes weeks, even months and the surface remains tacky for a very long time afterward. Fingerprints and smudges can also be a problem on the glossy finish.
I recently stumbled on a much easier and more efficient process that doesn't seem to have the same pitfalls as mixing your own from scratch. I found that marine grade spar varnish mixed with the asphaltum powder to a consistency of cake batter, sealed in an airtight container and left overnight, provides a much better outcome with shorter drying times and full cure at less than 30 days. You can also control the amount of the batch and the spar varnish has multiple other uses and a long shelf life. I've used this process on a number of items and have had good results. Plus, you don't have to mess with the turpentine and linseed oil. Reports from other folks who have used this recipe have been mixed. Some say it leaves a mottled finish with a lot of undissolved particles of asphaltum about the size of a grain of sand, in the finish. I too experienced this on occasion but have never heated this mixture which may make a difference. I wonder too if results may improve with the aging of the liquid mixture.
All of the products described are applied with a small brush, like an artist's brush and it's usually a good idea to paint on one surface at a time. I do the sides first: 1 lay the plane down on its side and paint it on, let it set for a half hour or so, 2. flip it over and repeat on the other side, 3, then lay it on the bottom and do the inside bottom. You can repeat it as many times as you like but remember it gets thicker and thicker and too many coats will obliterate the lettering on the casting. Stanley planes were japanned on the back edge but not the front edge so watch that if you are looking for an authentic look. Now it does dry quite glossy and I'm not sure if that was the way ol Leonard Bailey did his, but it's certainly an option for classic restorations of antique iron bottom bench planes or other tools that have a japan finish.
Here is a great article written by a fellow who has done extensive testing of different recipes, processes and applications of "...that stuff, japanning" . Definitely worth the time to read it as you will get first hand knowledge of his experiences. Japanning or The Art of Embracing the Arcane. The author, Greg Ricketts, has spent a lot of time and put forth some exceptional effort on this process and you should read the article as part of your learning curve.
Bottom line is that you will likely never develop a process that duplicates Stanley's but you can come pretty close to what your plane looked like when it came out of the box 100 years ago. You'll also be adding to this plane's life so someone else can enjoy it 100 years from now.