Is this iron salvageable?

[Brian Eaton]

I picked up a type 12 no. 4 yesterday at a flea market for a really good deal. It is cleaning up nicely but the worst pitting is on the back of the iron near the cutting edge.

084D5AAC-7132-44B4-A739-271BB9B071FD.jpg

Is it even worth trying to sand through that or grind past the worst of it?

[Nicholas Lawrence]

As you grind back, you will open new pits. Because it is at the back of the iron you will always have little nicks in the cutting edge where the pits are. You can probably get it to the point where it would work good for roughing, but it will be hard to ever get it to work well as a smoother.

I would look for another iron personally, if you want to use it as a smoother.

[lowell holmes]

Check this site,

https://www.google.com/search?q=plan...hrome&ie=UTF-8

[Brian Eaton]

Thanks for the input. I should have specified that I do have a spare iron I can use - was just curious if this one would be worth the trouble.

[Pete Taran]

I say go for it. I'd first grind back straight across to get on the other side of those pits. Once done, reestablish the bevel and then flatten the back. Once the worst of those pits are gone, you still have plenty of iron length to work with over the years. Just have a container of cold water near your grinder and take your time as that much grinding will generate some heat. I've restored worse. Finally, you might try to start that back flat by using a sander with a disc. Some 120 grit paper on a sander combo with a 6" disc will remove a lot of work and get you in the ball park. It's a worthy project, especially if the rest of the plane is nice. Sounds like this one is and it's early.

[Jim Koepke]

People pay extra for a toothing blade and here you have one made naturally.

jtk

[Scott Winners]

I probably would not try to restore it. You might in person lay a square on it to see if there is any place at all you could put the edge and have no pits, but I don't see one from here.

I have a couple similar irons stashed, I can't bring myself to throw them away, still dodn't know what to do with them.

[Pete Taran]

Check out the attached picture for more understanding about what I'm advocating. Those very tiny pits on the area to the right of the line will lap out. It's worth a try.

iron.jpg

[Brian Eaton]

Thanks, all, for the continued input. Given this is my first Sweetheart era plane I will definitely keep the iron. I think, for the time being, I’ll stash the iron and may at some point in the future try to grind past the worst of the pitting and see if I can get it into workable shape as Peter suggested.

[Tate Harmann]

What Pete said is exactly what I would do.

[Scott Winners]

I think you will have to take off at least as much as the line Pete drew. I am suspicious there would still be some pitting down by the second E in remove down at the lower edge as pictured. If I had it in my hand and was turning it to different angles under strong light I would maybe have a different opinion.

You might try just polishing that side of the iron to see how it looks freshly buffed before you take on all that grinding.

EDIT: If you find a clean line line the back when you get it shiny clean you might talk to a local to you blacksmith. It would save a bunch of time for you if you weren't in a hurry for a smith to anneal that blade for you next time the forge was hot - then you pick it up, take a hack saw to it, clean up the rough edges, take it back to the smith and let him/her re temper it next time they have the forge hot. My local guy would do that for probably 25 bucks or so, I would rather drive out there a few times then spend all that time at the grinder myself.

[Stew Denton]

Brian,

I think you are wise to keep the iron. +1, as Tate also is saying, on what Pete said.

I redid an iron as part of a plane I restored for a Christmas gift. It was pitted at the edge just like yours, but the pitting did not run quite as far into the iron as the pitting does on yours.

I did exactly what Pete is recommending, put some spray paint on the iron, scribed it square with a combination square and scratching tool, and then ground it back to that line. I ground it at approximately 90 degrees to the iron, and really took my time, using water to cool the iron very frequently just as Pete said above.

Once that was done, I ground the bevel back in. I did not grind the bevel to a sharp edge, instead I carefully watched the iron from end on, and ground the bevel until there was thin flat edge, very thin, again cooling with water VERY frequently. If you grind it to a sharp edge you are going to overheat that thin steel and soften it, and it will generally turn blue right at the thin edge indicating the steel becoming soft.

Once I ground it to that point I flattened the back side on the side opposite from the bevel. I started with a diamond stone and rubbed the iron until the scratch pattern covered the entire back. When I started the flattening process, the scratch pattern did not cover the entire back, once it did I went to a fine diamond stone. When the bigger scratches were gone I went to my finest diamond stone and then to a fine water stone and finally to my finest water stone, a King about 35 to 40 years old, 6000 grit.

I then used a similar process on the bevel but only with three stages. I first ground to 25 degrees using the fine diamond stone, and then ground very thin secondary bevel with the 6000 grit water stone until I had a fine bur across the entire edge. I then used the iron flat on the water stone and drew the iron toward myself 3 or 4 times and thus ground off the bur with the 6000 stone. Finally I stropped the iron with about 25 strokes on each side.

The iron cut very well, beautiful curls.

You probably already know all of this, and if so I am not trying to insult your knowledge, and if so, my apology.

Some key thoughts:

1. Once you get the flat back, never use anything on it again except your finest stone and the strop.
2. Never grind the edge to a sharp edge, as you will overheat it unless you have a water type grinder (I don't.)
3. Grind the iron back past the pitting as Pete showed in the picture. You have many years of iron left AFTER grinding off the pitting.
4. After using the plane, clean off any sawdust or shavings, they can help cause rust, which is why the pitting is very common in old plane irons where the chip breaker and iron come together.

Restoring an iron like you have takes me quite a bit of time, but once it is done keeping it sharp is not nearly as much effort.

In my view, you have an excellent iron to restore. You have a lot of iron left after grinding off the pitting as per the photo Pete attached, and the rest of the iron looks extremely good to me. Very much worth the effort.

One of the other guys, like Steven, Jim, or one of the others may chime in and give a faster fix than I did. What I do takes a lot of time, but once the back is flat and extremely smooth, to nearly mirror finish, you never have to flatten the back again. IF....you take care of it by never using it on any stone except your very finest stone and stop. (Some of these times I plan to get either an 8000 or 10000 grit stone.)

Regards,

Stew

[Rob Luter]

If this is to be a user, I would purchase a Hock replacement blade and call it a day. Keep the original for posterity.

[Derek Cohen]

Before you call it quits on the iron, try the Ruler Trick. If that does not take you deep enough, do a full back bevel. The aim is to get under the pitting. The RT will not affect the cutting angle, but a full back bevel will. Decide on what angle you want to add.

Regards from Perth

Derek

[Charles Guest]

I'd replace with a Hock iron and move on. If you do decide to grind away the section that has been identified, spend a little time lapping the whole back first to identify areas that could be a problem even further up the iron. You need to be able to make a really clear assessment before you decide. You can also buy a period correct Stanley replacement iron on EBay and through other sources.