Thursday, August 20, 2015

Rainy day projects.....a good day for rust.



This is getting to be a common theme I know,'s raining again.


The rain comes down here, nearly every day, but the last few hours have been heavier than the daily norm. It must be due to the tropical storm that just curved around to the south of us and though this isn't a direct hit, it still is dumping out.


The ever present humidity here on the east side of Hawaii is a killer on tools. I am continually presented with reminders to take better care of my tools, ironic, as so many of them came to me in somewhat neglected and rusty condition. The tools that see regular use aren't much problem. After use, they get a quick trip to the stones for a brief hone, then a good wipe with the macadamia nut oil that I've been using for rust prevention. The problem is storage. Put the tools in a box for a week and.....


I might as well put this humidity to good use. A good thick film of oil is the best prevention that I've got right now and a rust blackened finish is ideal for holding oil. Rather than watching stuff rust for all the wrong reasons, I might take advantage of the situation instead.



A little bit ago, Sebastian sent me a wonderful tsuki-nomi, knowing how valuable it would be for my impending journey into timber frame construction. The big 48mm nomi that he sent is the uppermost big guy, right under the iPhone.


The tsuki-nomi is great....really, really nice, but it wants to rust at the drop of a hat. The original forged black finish has worn away through the years, most notably in the areas where you anchor the blade using your left hand as a pivot.

I've written about rust blackening steel tools before, but repetition is something I'm good at (just ask my family, haha). Mostly, I just want to show off Sebastian's giant chisel!



Before I begin, I try to do something to protect any edges or surfaces that I don't want to rust. I used some good Tyvek tape to cover the bevel and back of the blade. Make no mistake, this is REAL rusting here, although it is shallow and doesn't cause pitting or anything.


I put a spoonful of regular salt in a glass or plastic container, then add some hydrogen peroxide.


Mix it up, wipe it on and let it rust.....Then boil to convert the red rust into black iron oxide. It's simple, satisfying magic. Or basic chemistry, take your pick.


The exact measures don't matter. The hydrogen peroxide will only dissolve so much (unless you use heat...then you can form a supersaturated solution, but I find its not worth the extra work), but the extra salt wont cause any trouble.



The only real rule for rust blackening steel is....cleanliness. Wash, degrease, wash again, and then maybe degrease again, it isn't too much work. I sometimes get better adhesion of the rust film if I first give the tools a short soak in a phosphoric acid wash. This gets into the tiniest pockets of rust and also seems to "activate" the surface of the metal.

This chisel was a bit of a bear and didn't want to hold the blackening very well along the upper ridges on the blade, nor along the shaft. When that happens, I wash some more, using good dish soap and some steel wool to micro abrade the surface. Then......the trick. I use the cheap chemical blackening agent, Birchwood-casey Super-blue. If you've ever used the stuff, you know that it might make the steel black, but it will also INSTANTLY rust. The combo of rust-bluing and Super-blue, a match made in heaven. I forgot to take a picture....sorry.


So Birchwood-casey, then more rusting/boiling will eventually build up a nice even coat of black oxide, so much so that the salt/peroxide solution stops rusting the metal. Then, with the metal still hot from the pot, dry it off and wipe on as much oil as it will take.



The cycles of caustic chemicals and boiling water are tough on the tape. It's better than nothing though. Now I need to sharpen this beast and put it to work.



Ellie is already busy today, sharpening stuff.

She just came in from the rain, looking all surly and mean, and figured it was time to put a good edge on the arrow that Brandon sent her. She's working on a chunk of Boiler Bay sandstone that we brought over from Oregon. Good girl.....she favors the natural stones.



Earlier that morning (it was sunny and hot until noon), I took this picture of a little canal that we drive over every day. Usually it is completely dry, but it's been raining a lot recently.




Later in the day, after only two hours of heavy rain.....




They issue flash flood warnings for this part of the island, when it rains heavy like this. Only 4 miles away, it hadn't rained at all. It is the deterioration of this exact drainage channel (and loads of irresponsible development) off of South Kulani road, that leads to notable occasions like this one in 2008, a few miles away, at the intersection of 39th and Pohaku.



We sure are glad that our realtor steered us away from that particular property, haha. See the guys in kayaks?





These rainy days are also good for other ongoing projects. I'm still working on a couple of different saws, slowly learning the art of "hizumi", which I understand as the straightening or massaging of tired and bent saw blades. This particular saw feels like a lost cause however, the rusty little ripsaw kataba/Hawaiian find.



The frustration of this is that at a number of different points I've gotten the blade very close to being good, but then I go a little too far and....damn. The mess really started after I got the blade straightened on the anvil, but then tried some light adjustment on a wooden block.


It's amazing how different it can be, the same steel, but using two different work surfaces. In a series of saw sharpening videos I watched, the presenter talks of preferring a mild steel block for certain procedures, as it "gives" more than the anvil. I would like to try that myself. I also need to polish up a nice block of this hard Ohia. It should make an excellent wooden anvil.




As I've been working this blade, I've been treating it as very much the learning experience, making the blade remarkably distorted, then bringing it back to (nearly) normal. These pictures show a couple different potato chip iterations.


The difficulty with this particular blade lies in the softness of the steel. The temper is just too soft, and the blade grows ever more distorted as I work on it. The steel is just too soft to make a good saw and when I bend the blade into an arc shape, on release it still retains some of the bend. That's not good.




I've learned some, but there is still a lifetimes worth of experience to be gained, many in fact. One of the greatest difficulties lies in finding someone to teach this stuff. Mark Grable has been very, very helpful in sharing his experience, but he's half a world away. I need something to to compare my efforts to.


Two weeks ago, this lot of dozuki and kataba saws came up on Yahoo Japan auction.



The detail photos showed that the saws looked to be old, but high quality. Some of them are missing a few teeth, but that's not my focus here. What really interested me was that there is ample evidence of the saws having seen the attention of a metate, some of the blades being dimpled as the surface of a pond. My thought is that if I examine these saws carefully, I might actually be able to learn something myself.






They arrived a few days ago.



I got a big saw, too.


  1. I guess I'm sending you the small slick for some magic blackening. I love the way it looks, and when I tried was a great great failure. Didn't stick as you say. I'm getting steel blue next month and try again. The air here seems very salty here, or so my tools tell me, I need to learn it.

    I need a video of that saw in use, looks like twice the size of mine and mine cuts fast already, I guess this is a fat wood eating monster.

  2. It's raining a ton here, as well. One of my uncles, who came to America from Ireland, said he wants to move from Denver to Rochester, as the constant grey skies and greenery from all the rain reminds him of Ireland.

    Alright, I think it's time to bite the bullet and look at Buyee for myself: I really want to start making shoji, and get a nice dozuki...or five. Tell me where you can find a file big enough for that saw, I can't find a 200mm one for my rip saw!

  3. Ahh! Big saw, very nice. Perfect for a man that has some trees to cut. I'm really excited now to see how it works for you, the plate looks like its seen some recent use, have you tried it yet?

  4. I have had some good luck after blueing/rusting steel, heating it up and melting candle wax on the surface. The metal has to be hot enough for the wax to soak into the surface of the metal. Once it cools, it forms a durable rust barrier. It's ok to add some oil after that too but the hot wax seems to work pretty well.

    1. Hi Greg!

      As a matter of course, I use Johnson paste wax for nearly everything, and it has worked well enough in the past. I didn't bring any with us when we moved here, and it's just been plain foolishness that's kept me from buying more, but.....that ends today!

      But using candle wax would be even better! And we already have some candles right here. I'm definitely trying this as well.

      Thanks for your idea!


Like all of us, I am figuring this out as I go, so when you see something that is incorrect or flat out wrong (and you will!), let me know. This is a learning process. Real people and names, please. Constructive comments and questions are very welcome, but hate speak/politics are not! Life (get one!) is too short.

Thanks, Jason