Bent plane iron

[Daniel Guilderson]

I'm just beginning with woodworking and I'm trying to sharpen an old Stanley Bailey plane iron. I wanted to polish the face before working on the bevel. It was difficult to get down to the edge. I checked the iron and it was clearly bent with a gentle convex curve on the face. I checked the cap and it is slightly out of flat at the point closeest to the cutting edge but that would have caused the iron to bend in the opposite direction. So I d understand what's happening. Any suggestions?

[Jim Koepke]

Howdy Daniel and welcome to the Creek. Your profile doesn't indicate a location. I am always curious as to where people call home. Often they tell me and then a month or two later my memory fades...

As to your particular plane blade there is no telling what has happened to cause it to become curved. Most likely a previous owner added a little tension to the chip breaker in an attempt to make the blade and chip breaker mate up better.

Here is an old post of mine showing one of my planes with a similar problem:

http://www.sawmillcreek.org/showthre...86#post1158886

jtk

[Bob Woodburn]

I would say it is hardened steel and thus wasn't bent by any bending force. I have plenty of Stanley irons that are warped to one degree or the other. At least that is my conclusion from putting together the fact of convex on one side and concave on the opposite. To the extent the convex side is out of proportion to the concave side, I'd imagine that extra amount is due to the unintended or intended process of repeated round-over. Round-over is easily produced by whetting or 'sharpening' the flat side with a concave or 'dished' whetstone (or it's many replacements like belt sanders and so forth), generally to try to "get the burr off" an already rounded-over flat side. Certainly, I've seen a couple blades that were obviously ground on both sides (by an impatient carpenter?).

All this leads to the often repeated received wisdom that once the flat is flat don't return.

Of course, we (you) have the popular option of the "ruler trick" or "micro-bevel" on the flat side. This is legitimate to speed things up, to save you from the agony of trying to flatten the face, or sending it off to be surface ground back to flat. It is also a dandy way to save an old Stanley blade that is otherwise useless due to pitting and "micro-pitting" far up the flat face edge. So my advice would be read up on Charlesworth's suggestion.

PS: After posting, then reading Jim's interpretation, I see I'm confused about your description of the problem.

[Daniel Guilderson]

I fixed my profile. I'm from the Boston area.

Sorry about the brevity of the description of the problem. I was trying to write that up on a small smart phone. Maybe a diagram might help:

Face side
------------------/
-----------------/ cutting edge
Bevel side

The iron has a cup on the bevel side and a round-over on the face side. It is most pronounced in the direction of the end to the cutting edge direction and most likely it is also somewhat curved from side to side as well. So I guess you could say that the bevel side is like a shallow bowl and the face side is corresponds to the bowl shape as well. If I lay the iron face side down on a granite plate (I bought one from Woodcraft) it rocks slightly. This makes it really hard to polish the face. I spent around 5 hours on it already and I still have about 1/16" on each corner to go. The middle is all the way to the edge. I started out trying to polish 2 inches from the cutting edge but I gave up and now I'm focusing on 1 inch from the cutting edge. I'm concerned that there is something seriously wrong with my frog or cap iron that is going to cause me headaches down the road. But I couldn't figure out what might have caused it. If it is something that is not out of the ordinary then I will just accept it and do my best to polish the face all the way to the edge. But if there is a serious problem, I want to address it now rather than later. The funny thing is that I also have a Buck Brothers #4 and I found it was also cupped the same way. But I didn't check it until after I had tried to see if it would fit my Stanley. I clamped it tight to the Stanley cap iron and then put it into the plane and since the lever cap was a little tight I loosened the screw so that the lever could be snapped down without too much difficulty. When I realized that both irons are now cupped the same way I started getting worried. Thanks for kind advice!

* edit: when I say clamped the iron to the cap iron, I just mean I screwed the cap screw tight to mate the cap iron to the plane iron in the usual way.

[Bob Woodburn]

Daniel, I think your problem is as I first understood it. If you have the iron face flat to within 1/16" of the edge-corners, you are there now, in my opinion. You could simply chamfer the corners, as many do anyway, and fit up the chipbreaker as necessary. All this warping and rounding-over of plane iron faces is a very common problem. There is nothing unusual about it. Your plane's ability to function is not impaired given how you are fixing the problem. You are doing a great job, though 5 hours on the flattening puts you in the very meticulous, nearly perfectionist category. I say that with admiration and warmth.

That the bevel side of the iron is concave a bit (or a lot) side to side (or to and fro), will mean the iron will not rock side to side on the frog, as it would if the bevel side was convex side to side. I say that assuming you have an old, laminated, thin Stanley iron that should allow the full length of the iron to bend enough that the iron's corners touch down close to the throat (bottom of the frog). Otherwise, it could dive under wood resistance. You can check this when things are tightened up by seeing if you can slip cigarette paper (or a 0.001 shim) up the mouth from the bottom between the frog and the iron. Chatter and variable chip thickness would be the tip off in use.

Pay attention to how the lever cap comes down on the hump of the chipbreaker when you put it together. The hump of the chipbreaker is unlikely to be a precision stamping. If your frog surface is flat, and your bevel side of the iron is concave side to side, it won't rock or dive from varying resistance from the wood. If the lever cap mostly comes down in the middle of the hump (side to side), you can see that the load from the tight lever will balance the chipbreak/iron rigidly on the frog. The problem is when the frog or iron touch as a curve to flat or curve to curve. You're a smart guy. This is obvious to you.

There are ways, easier and quicker than 5 hours on a hone/sandpaper, to get the hump out of the iron face and put in a slight dish up to but not through the cutting edge (sort of like the Japanese blades). You'll want to think about this before your next 5 hour romance with a crooked iron. I spent some of this past winter trying out freehand bench grinder and Tormek methods to do this. Using the sides of the wheels doesn't work. Period. Nor does using the grinding wheel face alone. But that's for another time.

[Mike Henderson]

Rather than put a lot of time into that blade, I'd buy a modern blade. A modern blade will be flat and will be thicker than the old Stanley blades. In my opinion, the greatest improvement you can make to an older plane is to put a modern blade in it.

Mike

[Chuck Hart]

+1 on what Mike said. Modern blades are not that expensive period. Save yourself for the final test to all woodworkers...sharpening. 90% of a planes performance is in the sharpening

[Jim Koepke]

Home Depot has a $3 blade for a #4/5 plane. It is a decent blade.

jtk

[Robert Engel]

Once again, Mike is right on the money.
I've been very happy with the Veritas blade/cap iron combos.
You can also buy replacement Stanley type blades.

I would get both a blade and a cap iron.

I wouldn't waste $3 for a HD plane blade.

But I keep a couple old plane blades around they are handy and make great glue scrapers.

[Jim Koepke]

Once again, Mike is right on the money.
I've been very happy with the Veritas blade/cap iron combos.
You can also buy replacement Stanley type blades.

I would get both a blade and a cap iron.

I wouldn't waste $3 for a HD plane blade.

But I keep a couple old plane blades around they are handy and make great glue scrapers.

Often times a replacement blade and cap iron will cost more than what was paid for the plane in the first place.

The HD blades are actually a decent blade. One of my #4s has one of these and it has performed surprisingly well.

The Stanley cap iron seems to work fine on my Hock blades. As is so often the case:

YMMV!!!.jpg

Glue scrapers, marking knives and many other uses.

jtk