Making Plane Irons for wood planes?

[Karl Krauter]

I've been lurking for a while now, decided to get a user name last fall sometime. Anyway I've done some searching on making irons and haven't come up with much, I did find one thread about making irons for students but it wasn't what I am looking for. I apologize if I am asking something that has been answered.

Ok so here is the question, has anyone made irons and chip breakers for krenov style planes? I'm not to worried about the metalergy portion (read further), mainly looking for design and any pitfalls issues.

I have 2 friends that are blacksmiths, one of which is a machinist and blacksmiths professionally. Both of them are very interested in the project and have dealt with with O1 steel. Actually they really want to make there own planes too. I have not built a plane before, but after reading David Finck's book am not intimidated by the prospect.

One last thing, I'm not a complete newbie to woodworking, I'm maybe an accomplished newbie. Mostly have worked with poplar and pine, and a little with western juniper. I'm just trying to build up my tool collection, since my friend who got me into woodworking and hand tools moved away with all his tools. Hence wanting to build some wood planes.

Again sorry if I am out of line on the question.

Karl

[Brian Kent]

Karl, welcome. I've made a few planes but certainly don't have the tools or skills to make the irons. Good luck on that one and post along the way.

Brian

[David Gendron]

There is a few Creekers that did post about plane making involving irons as well... I f can remenber, they mostly used thick steel and didn't bother with a chip braker. An other option would be to get a set of Hock iron/chip braker assembly and go from there, his stuff work realy well, so I'm sure you could use that as an idea!!

[Larry Williams]

Why a cap iron? They cause more problems than they solve. When those who repeat the mantra about cap irons being an improvement, they always fail to mention the fact that cap iron planes were historically always common pitch planes. Try and find an old double iron plane that isn't common pitch, if you doubt what I'm saying. The only old double iron planes at a steeper pitch I've ever been able to find are a very few Slater infills. Slater made custom planes as well as offering kits and I suspect those I've seen were craftsman made kits. The traditional cutting geometries of York pitch, middle pitch or half pitch are far more effective at dealing with difficult or figured grain than cap irons. The British double iron planes were almost always bedded at 47.5º while American double iron planes are 45º. I consider them both common pitch.

[Michael Faurot]

If you, or your friends, all ready know how to do the metallurgy for O1 tool steel, then making blades is pretty straight forward. As others have mentioned, you don't need a cap iron, just use a thicker piece of steel. This simplifies both the construction of the plane and its use. So now all you're dealing with is a rectangular piece of metal with a bevel on one end.

[Steve knight]

yes chuck the chip breaker. I have made over 3500 planes and never had anyone say they needed one.
but 0-1 irons don't take much to make. cut to length grind the basic bevel get them hot enough so a magnet does not stick dunk in oil and throw in an oven at 300 for a hour or so and your done. use 1/4" for less warpage problems.

[Bob Glenn]

Karl, I made three plane irons from A2 steel, (see A Plane is Born in Neander). If I had to do it again, I would use O1 steel since heat treating A2 requires a special oven. I used 1/4 steel a chip breaker is not needed. One other tip, if you grind the bevel on the tool steel, be careful you don't over heat the steel because you will work harden it and it will get harder and harder to grind. I ended up cutting the section I ground off then milled the bevel. You could also cut the bevel with a hack saw.

[Karl Krauter]

Thank you everyone for the information. Looks like I will be ordering some .25" O1 and ditching the chipbreaker. I was just going from David Finck's book, so that is why I was worried about chipbreakers. I will try to do some photo documentation for the project, at least the metal end of the plane. I'm sure you guys have seen plenty of newbies hack up some wood and call it a plane.

Again I greatly appreciate everyone's input.

Karl

[Sam Takeuchi]

Yes, pictorial will be greatly appreciated. Just be careful when you heat treat your blade. Safety first!

[Karl Krauter]

Yes, pictorial will be greatly appreciated. Just be careful when you heat treat your blade. Safety first!

I'll be watched carefully by the pro's, I'm sure we will do a test run with a couple pieces. Then go into production. Hopeing to make around 20 blades. One of them would like to laminate some blades, as he had watched at a blacksmith conference. We'll see how that works too.

karl

[Karl Krauter]

Are there any preferences for length. For the krenov style plane it looks to be kept short. Any reasons for not doing this?

[Kevin Lucas]

I just checked Wooden Planes and How to Make Them by David G Perch and Robert S Lee and I cannot see any thing for length. From most of the drawings it SEEMS to be body height, plus wedge height and add about 2 inches? That should give enough room for a hammer to tap the iron for left and right alignment.

I have a relative that wants to give me a forge and so tempted to try my own irons. Can't wait to see how yours turn out )

[Andrew Recher]

This is something that I've been wanting to do for a while (planes and plane blades). I've forged a number of knives in the forge I'll describe below but haven't gotten around to the plane blades.

Your doing the right thing by going with purchased O1. There's a lot of scrap carbon steel out there but you can't always tell what you have and it sometimes requires a little experimenting to get it to harden properly. If you can harden it at all. The couple of plane blades I did try to make I used old lawnmower blades for the steel but I couldn't get them to harden. In my opinion it just isn't worth the time using unknown ( though I have had pretty good success using some old rotary hoe tines from old ag. equipment. From my experience, Steve Knight's advice above is pretty much right on the money.

I built a small forge that works really well. It's based on a design by Tim Lively. It uses all readily available parts from the hardware store. The tub is filled (sloping down to the pipe to form a v shape) with a mixture of hardwood ash and clay (soaked kitty litter, unused preferably) and allowed to harden. I used a hair dryer for the air source for a while but I now use a small squirrel cage from a bathroom fan. I usually buy 20 lb. bags of hardwood lump charcoal for fuel (not the presssed briquettes) though when I started out I used wood and just made my charcoal as I worked (it's a lot smokier that way though).

It gets quite hot, too hot in fact, if you blow the air too hard or walk away too long you can burn the steel pretty easily. It does take some practice to get a nice even heat over the entire piece. Some smiths will bury a piece of iron pipe in the coals to place the blade into. That helps to even out the heat.

Hope you'll be able to share some pics, so that those of use without much extra time for our hobbies can be jealous.

Andrew

[Jonathan McCullough]

This may seem too simple, but has anyone tried taking two inexpensive store-bought plane irons, and epoxying them together?

I'm serious. Think about it. What makes a plane iron work is that it uses two surfaces--the back and the bevel--to create a single cutting line. That's true whether the plane iron is 1/32" thick or 5" thick. What makes the thinner plane irons disadvantageous is that their lower mass takes less energy to make them resonate, i.e. vibrate, in other words, "chatter." You can reduce this chatter in one of two ways--add mass, or find a structural way to pre-stress the iron. Using a thicker blade adds mass, and using a chipbreaker not only adds mass but also puts tension on the iron itself.

All things being equal, nothing would beat the mechanical adhesion of o-1 tool steel to itself. But two plane irons epoxied together would add mass, wouldn't interfere with the business end of the cutter, would provide a slot for the chipbreaker screw if you wanted one, and would cost a whole lot less ($6 where I live for two irons) for an experimental wooden plane.

You could silver solder them together using the technique Bob Smalser used for his high-angle smoother, but at those temperatures (700 degrees?) you may be messing with the temper of the steel. So why not epoxy? Why not?

[Sam Takeuchi]

Even before going into epoxy stuff, the main problem with those cheap blades is that they are soft and don't hold edge well. I suppose heat treating them prior to epoxying them together may be necessary. Especially considering the fact cheap store bought replacement blades nowadays are made from suspicious quality steel.

But if heat treating is required, then it's not too much more expensive to buy a bar of O1 to make solid blades, and even have choice over the kind of steel you use.

That aside, I don't know how well epoxied blade would perform. Personally I wouldn't bother with junk quality blade. For $6, you are probably better off buying a tapered laminated blade for wooden planes.