Flattening Plane Irons

[Steve H Graham]

I have bought 4 planes in the last month, if spokeshaves count. I am getting very familiar with flattening the backs of plane irons.

Yesterday I put in about two hours on a new Stanley spokeshave iron. I was not too happy about it. I used a DMT extra-coarse stone part of the time, but I eventually put 100 grit paper over the stone and used that. Still pretty slow. I am not really content with the results. I believe there is a small area I should continue to work on.

Is there something faster out there, that either stays flat like a diamond stone or is easily trued up?

[Pete Taran]

The easiest way to flatten this kind of stuff is on the side of a wet water wheel. I have 2 tormek grinders. One has the stock 220 grit stone in it, the other the 6000 grit waterstone. You just hold the iron on the side of the stone for 15 to 20 seconds at a time, and it's flat in no time. When done with the 220 grit, switch to the 6000 grit. The whole process takes 5 minutes. It's crazy fast and takes ALL the grunt work out of the process. it cuts fast because the water is constantly removing the debris from the wheel. Short of a surface grinder, this is your fastest route.

I was always skeptical about the utility of those Tormek grinders. They cost a lot and the gizmosity factor is off the charts. However, after buying one, it is the Dog Diggity of sharpening contraptions. Anyone who loves to work wood but hates to sharpen should own one. I was so impressed, I bought another one just so I didn't have to change wheels.

[Steve H Graham]

It's weird that big companies that could do this job for their customers so easily and cheaply shoot their irons out the door with big dips in them.

[Archie England]

Pete T: Please explain a little more about how you hold the blade to the Tormek wheel's side. I've done that a few times to hasten the grinding process but sometimes I get less than satisfactory results.

Steve G: (Don't we all love sharpening threads!!!) I get inconsistent results with sandpaper but still consider the lower grits a great way to remove metal on dished blade backs. However, for consistent results I use very coarse water stones (Cerax 320 and Sigma 400). For me, synthetic water stones, being significantly faster than oil stones, are adequate and somewhat equal to sandpaper in speed (though that's not always true when compared to 80 grit or less sandpaper). I've used up diamond plates a little to quickly, so I'm less willing to use that medium on blade backs now.

However, in watching a Paul Sellers video on rehabbing an old plane, he significantly shortened my sharpening time when he gave a convex blade back a single blow on a flat surface. This actually worked for me because it removed the belly back that would have taken forever to grind down. However, to all those who do this differently, I intend no offense to the numerous other good ways of arriving at the goal. If it works; it must be good.

[Allen Jordan]

The hammering technique is interesting, sounds like it would work well. I sometimes purposefully grind a hollow into older blades to make lapping easier.

[Robert Hazelwood]

The best thing I have found is to get a flat granite plate and stick on some 60 or 80 grit PSA sandpaper. Woodcraft sells a 4"x 18" granite plate for pretty cheap, which makes a nice long sanding block.

I've tried coarse waterstones, diamond stones, oil stones, etc. but nothing cuts faster than a fresh sheet of coarse sandpaper. Just remember to keep the paper fresh, as it seems to remove as much material in the first minute or two of use as it does in the next 10.

Once the back is even on the 80 grit, I can bring it over to the coarse DMT and then the Shapton 1000 to finish the flattening, which doesn't take too long. Then it is ready to move onto the normal sharpening routine.

[Andrew Hughes]

Here's a method that I use when I need to remove a lot of steel.Thats a Finck blade under my right hand A2 steel.I can really bear down with a stick across the back.

[Steve H Graham]

I am going to look into the hammering thing. I don't think it will help me with the iron I'm working now, because it's nearly done. I assume that straightening an iron with one side which has already been partially flattened will make things worse.

Someone just suggested putting a small bevel on the flat side of the iron.

[Allen Jordan]

I am going to look into the hammering thing. I don't think it will help me with the iron I'm working now, because it's nearly done. I assume that straightening an iron with one side which has already been partially flattened will make things worse.

Someone just suggested putting a small bevel on the flat side of the iron.

The ruler trick will pretty much always work, though it's less traditional.

[Steve H Graham]

You know what? I'm going to get some coarse sandpaper. I am seeing some interesting ideas which I may try later, but I feel like getting the two irons I have in front of me fixed today.

The Tormek idea sounds foolproof, but I think an even better idea is to make a friend who has a Tormek and save money.

[Patrick Chase]

I have bought 4 planes in the last month, if spokeshaves count. I am getting very familiar with flattening the backs of plane irons.

Yesterday I put in about two hours on a new Stanley spokeshave iron. I was not too happy about it. I used a DMT extra-coarse stone part of the time, but I eventually put 100 grit paper over the stone and used that. Still pretty slow. I am not really content with the results. I believe there is a small area I should continue to work on.

Is there something faster out there, that either stays flat like a diamond stone or is easily trued up?

I use diamond paste starting at 60 um grit size on cast iron and/or mild steel plates. I have a set of 8" by 4" precision-ground 1018 plates that are particularly nice for flattening. They stay pretty flat, and in my experience it's by far the fastest hand-powered flattening method. It isn't cheap, but neither are sandpaper or DMT plates.

I also have a Tormek, and as Pete says that's a very efficient option with some practice. You have to be very careful not to "rock" the iron on the side of the wheel, but other than that it isn't very demanding.

[Allen Jordan]

Wouldn't the tormek wheel side distort with use? Seems like a flat grinder like a worksharp might work better.

[Pete Taran]

Foley used to make a scissors sharpener which had a cast iron plate and you used grinding compound on it. It worked pretty well, but I sold it when the Tormek came along. A lot faster and less mess. You have to be smart about how you do it. Keep the blade moving along the side of the wheel and press it dead flat. The stone is pretty hard, so it can take the abuse. I haven't noticed any dishing in quite a bit of plane iron work. Works for chisels or whatever else you have that needs sharpened.

[Pat Barry]

I have bought 4 planes in the last month, if spokeshaves count. I am getting very familiar with flattening the backs of plane irons.

Yesterday I put in about two hours on a new Stanley spokeshave iron. I was not too happy about it. I used a DMT extra-coarse stone part of the time, but I eventually put 100 grit paper over the stone and used that. Still pretty slow. I am not really content with the results. I believe there is a small area I should continue to work on.

Is there something faster out there, that either stays flat like a diamond stone or is easily trued up?
When you say back side, which side do you mean exactly? Is that the cap iron side?
How much if the are you trying to flatten? The whole thing or just a portion?

[Martin Shupe]

Here's a method that I use when I need to remove a lot of steel.Thats a Finck blade under my right hand A2 steel.I can really bear down with a stick across the back.

What is the brand of the flattening plate you are using?

[Andrew Hughes]

That would be a Shapton DLRP.Its very expensive but it does have too sides one for stones and one for steel.Its also bronze and very solid.
The stone side looks like this.

[steven c newman]

I will start out with the hammer, IF needed. I will then use the side of my grinder's wheel. Does not take much time at all. While I am using an upside-down beltsander and a MK1 honing guide to work on a new bevel....I will hold the back onto the belt.

At each stage after that ( oil stones, W&D Paper) I will work the back a few times as well.
Water? I do keep a large cup of water nearby.....

[Archie England]

I also have a Tormek, and as Pete says that's a very efficient option with some practice. You have to be very careful not to "rock" the iron on the side of the wheel, but other than that it isn't very demanding.

Okay, that's what I was asking Pete about in an earlier post. Any slight lift of the blade tend to score the blade (or the stone), and it's a little tricky (well, the way I've done it).

[Patrick Chase]

That would be a Shapton DLRP.Its very expensive but it does have too sides one for stones and one for steel.Its also bronze and very solid.
The stone side looks like this.

You do not want to use the diamond ("stones") side for anything but fairly fine waterstones. Shapton's diamond plates are incredibly flat and uniform (none of the "rogue diamonds" that plague DMT), but they're made by resin-bonding the diamonds to the substrate instead of nickel electroplating. If you take steel or a very coarse stone to them you'll strip the diamonds.

Also, when Andrew says "very expensive" he means $550. If you have to ask, you can't afford it.

This is basically the same idea but less exorbitant: http://www.leevalley.com/us/wood/page.aspx?p=59752&cat=1,43072

I use commodity precision-ground 1018 plate from McMaster-Carr, which is cheaper still.

[Steve H Graham]

When you say back side, which side do you mean exactly? Is that the cap iron side?
How much if the are you trying to flatten? The whole thing or just a portion?

I am trying to flatten the cap iron side. Just a little strip near the cutting edge.

[Andrew Hughes]

What stones or steel did you use that stripped off the diamonds?
I do remember Stanley mentioning not to try and flatin a Hard Arkansas because it wouldn't be good for the stone side.
I also have the diamond on glass and I like it better because it's light.
Thanks for the heads up.

[Matthew Hutchinson477]

I feel your pain, Steve. I too have no suitable power tools for flattening metal. I've restored more than a few hand planes and chisels using only non-powered hand tools. For plane blades, a diamond stone worked better for me than sandpaper. I tried silicon carbide grit before, too, but that requires a suitable surface like a dead flat piece of steel or a piece of plate glass you don't mind destroying. I tried using a beltsander once to at least get a couple blades close while getting rid of the pitting but the blades always ended up slightly convex rather than flat, which is about the worst shape you can have. Once a plane blade is rounded like that getting it flat is very difficult no matter what method you use.

So, onto the hammer method. I can attest to it and honestly it's been the fastest, easiest method I've found short of power tools. I think I saw it originally in a Paul Sellers video. It does work but make sure you use a hammer with a big, slightly convex face. A lot of metalworking hammers, like planishing hammers, have faces that are slightly rounded like this. If the face is completely flat you'll either have to hit the blade dead on (which is very difficult to do) or you'll end up putting a dent in it with the edge of the hammer face. Though I think a good metalworking hammer would be ideal, I've done it with a plastic faced hammer before and it worked well enough. If you don't have a dead flat metal surface like an anvil, a dead flat piece of hard wood can work but make sure you hit the blade far enough back from the cutting edge because you will likely end up with a hollow. That was my experience using a hard piece of wood rather than an anvil, at least.

[Steve H Graham]

The 60-grit paper I bought today definitely works faster than the 100-grit I was using yesterday, but on the whole, I wish I had a surface grinder.

I have to check out that Sellers video.

[Patrick Chase]

What stones or steel did you use that stripped off the diamonds?
I do remember Stanley mentioning not to try and flatin a Hard Arkansas because it wouldn't be good for the stone side.
I also have the diamond on glass and I like it better because it's light.
Thanks for the heads up.

There are many acciynts of worn out Shapton plates out there, for example from Chris Schwarz (http://www.popularwoodworking.com/woodworking-blogs/chris-schwarz-blog/dmts-dia-flat-takes-a-crazy-beating). I have the single-sided version (https://www.amazon.com/Shapton-Diamond-Glass-Lapping-Plate/dp/B0034YT5VO) and haven't yet managed to strip any significant # of diamonds, though. I've also never disobeyed the instructions, which say:


Never use it on steel
Never use it on any waterstone more coarse than the 500# Glass stone.

Inspection under a microscope revealed that the diamonds are bonded instead of nickel-electroplated, and my experience as an engineer leads me to believe that that's why Shapton imposes the constraints they do. Shapton offers to strip and recoat the plate if you wear it out, but it isn't cheap (a couple/few hundred IIRC).

Even the "best" nickel-based plates are no guarantee BTW. I once stripped most of the diamonds from a Dia-Flat (the plate whose durability Schwarz proclaims) by "enthusiastically" flattening a Sigma Select II #240 with it.

[Patrick Chase]

So, onto the hammer method. I can attest to it and honestly it's been the fastest, easiest method I've found short of power tools. I think I saw it originally in a Paul Sellers video. It does work but make sure you use a hammer with a big, slightly convex face. A lot of metalworking hammers, like planishing hammers, have faces that are slightly rounded like this. If the face is completely flat you'll either have to hit the blade dead on (which is very difficult to do) or you'll end up putting a dent in it with the edge of the hammer face. Though I think a good metalworking hammer would be ideal, I've done it with a plastic faced hammer before and it worked well enough. If you don't have a dead flat metal surface like an anvil, a dead flat piece of hard wood can work but make sure you hit the blade far enough back from the cutting edge because you will likely end up with a hollow. That was my experience using a hard piece of wood rather than an anvil, at least.

I'd be careful about doing that with any really hard plane iron. It's pretty easy to do damage that way. Hardened steel sometimes doesn't take very well to being beaten on with a metalworking hammer.

[Matthew Hutchinson477]

I'd be careful about doing that with any really hard plane iron. It's pretty easy to do damage that way. Hardened steel sometimes doesn't take very well to being beaten on with a metalworking hammer.

Ah, yes, I forgot to mention the importance of tapping gently. With the plastic faced hammer I gave the blades a solid hit but with the planishing hammer it was a lot more light taps. I'm no expert on the subject by any means so please correct me if the metalworking hammer is just a bad idea entirely. It did, however, work for me when I tried it.

[Patrick Chase]

Ah, yes, I forgot to mention the importance of tapping gently. With the plastic faced hammer I gave the blades a solid hit but with the planishing hammer it was a lot more light taps. I'm no expert on the subject by any means so please correct me if the metalworking hammer is just a bad idea entirely. It did, however, work for me when I tried it.

Depends how hard the piece your hammering on is. For typical plane irons at, say, Rc60 light tapping should be fine.

Be sure to wear goggles if you ever do that to a fully-hardened tool like some files though :-)

[steven c newman]

I seem to get a few irons through the Dungeon Rehab Center ....not only do I have to flatten the back, I also have to straighten the bowed iron along it's length...

Ball pean Hammer, and set the bad spot right over the leg of my bench. Same goes for a few chipbreakers. Rather than trying to sandpaper a cb flat enough to mate the iron's back, I wind up using than same ball pean hammer. Then it doesn't take so much removal of metalto fettle the chipbreaker.

2+ hours to flatten an iron's back? You have got to be joking. Takes me MAYBE ten minutes. haven't time to waste on such things. 2 hours? I am glad I am not paying that person by the hour....used to call that kind of worker a Milkman, because he was "milking" the job.

[Archie England]

2+ hours to flatten an iron's back? You have got to be joking. Takes me MAYBE ten minutes.

Steven, I've had a few rehabs that took over an hour for back flattening (and a few more that I just gave up on and used the ruler trick). I've got one Sigma stone that I will no longer put on chisel or plane back because it leaves such deep scratches. This stone is a metal hogger and is fine for cutting and reshaping bevels; but it's way to coarse for a blade back that needs to get relatively flat and free of grooves.

[Patrick Chase]

Steven, I've had a few rehabs that took over an hour for back flattening (and a few more that I just gave up on and used the ruler trick). I've got one Sigma stone that I will no longer put on chisel or plane back because it leaves such deep scratches. This stone is a metal hogger and is fine for cutting and reshaping bevels; but it's way to coarse for a blade back that needs to get relatively flat and free of grooves.

Sounds like the Power #120? In addition to being coarse that stone is also made up of SiC, which adds to its aggressiveness.

With that said it all depends on how far out of flat the tool is. #120 is ~1/10 mm particle size, so if the tool is out of flat by more than a few times that then it can still be faster overall to start with that stone. Put another way, you'll spend much less time on the next stone up to remove 1/10 mm deep scratches than you would flattening a tool that's a few tenths out. A good straightedge and some shim stock are helpful to figure out where to start.

[Dennis Yamamoto]

I use commodity precision-ground 1018 plate from McMaster-Carr, which is cheaper still.

Patrick,

Can you let us know the part number for the McMaster Carr 1018 precision steel. Also, where do you get the diamond paste?

I have a few wide chisels and gave up after a few hours of trying to flatten the backs.

Thanks,

Dennis

[Charles Bjorgen]

Hi Steve -- I picked up this tip from David Weaver in one of his wood plane making videos. It just makes use of a chunk of 2x4 that allows you to bear down hard on whatever medium you're using to flatten. I use anything from diamond plates to 80 grit self stick sandpaper on a granite block. It really saves wear and tear on your fingers.

[Bruce Haugen]

I use diamond paste starting at 60 um grit size on cast iron and/or mild steel plates. I have a set of 8" by 4" precision-ground 1018 plates that are particularly nice for flattening. They stay pretty flat, and in my experience it's by far the fastest hand-powered flattening method. It isn't cheap, but neither are sandpaper or DMT plates.
SNIP


I was lucky enough to come across a chunk of cast iron 1" X 3" X 12". The local community college machine tools course students flattened it for free. So far the only cost is for the diamond paste, about $12. Even 15 micron past made child's play out of a 2" chisel.

[Archie England]

Patrick, yep, it's the Sigma 120. And i will use it on stones that are bunged up badly, but not on new ones. It's nearly as fast as a grinder on bevels, especially since there's no chance of drawing the temper of a blade.

[Steven Mikes]

Hi Steve -- I picked up this tip from David Weaver in one of his wood plane making videos. It just makes use of a chunk of 2x4 that allows you to bear down hard on whatever medium you're using to flatten. I use anything from diamond plates to 80 grit self stick sandpaper on a granite block. It really saves wear and tear on your fingers.

This is brilliant! I guess you'd have to keep your sharpening medium on the edge of your bench though since the screw heads protrude. Steve Graham I feel your pain though, I just went through the exact same thing. 60 grit sandpaper helped some but it still takes forever.

[Charles Bjorgen]

You're correct, Steven. Actually I use a holder for the diamond stones that elevates the nuts and bolts enough so they don't contact the bench surface. When using sandpaper on the granite block it's off the edge of the bench. Most vintage plane irons I've acquired have needed a lot of work. This basic little jig has has really saved my hands.

[Patrick Chase]

Patrick,

Can you let us know the part number for the McMaster Carr 1018 precision steel. Also, where do you get the diamond paste?

I have a few wide chisels and gave up after a few hours of trying to flatten the backs.

Thanks,

Dennis

9517K496 (http://www.mcmaster.com/nav/enter.asp?partnum=9517K496) for the steel. It's a 4x24 piece that I cut into 3 8x4 plates.

I get my diamond paste from a mix of McMaster-Carr (Sandvik/Hyperion), PSI, and Norton. McMaster is probably the most cost-effective source for quality monocrystalline compound.

[Pat Barry]

Hi Steve -- I picked up this tip from David Weaver in one of his wood plane making videos. It just makes use of a chunk of 2x4 that allows you to bear down hard on whatever medium you're using to flatten. I use anything from diamond plates to 80 grit self stick sandpaper on a granite block. It really saves wear and tear on your fingers.
It seems to me that bolting the blade down like that might just straighten the blade a bit if it were convex. OK, but then it will spring back a bit when unbolted. No doubt it makes a good blade holder though.

[Charles Bjorgen]

As it turns out David Weaver, perhaps inspired by this thread, just uploaded a video to YouTube that shows his jig that inspired me. Do a search for " The best way to flatten a plane iron." David's jig has longer handles but he explains that one needs to hold the jig firmly on the center of the back in order not to rock it on the medium.

[Patrick Chase]

It seems to me that bolting the blade down like that might just straighten the blade a bit if it were convex. OK, but then it will spring back a bit when unbolted. No doubt it makes a good blade holder though.

Curve along the lengthwise/longitudinal axis is mostly harmless and need not be flattened out. It's not like that iron is going to be longitudinally flat after you attach a cap iron to it, after all.

[steven c newman]

Unless the chipbreaker is also bent....BTDT.

A LOT of these old vintage planes have just sat around on a shelf..for YEARS. Left with everything cranked down type, and half the time put together backwards. Lever cap slowly over time (Decades?) will bend things out of shape, simply because someone had cranked that bolt down as far as they could. Have seen many an old plane come through my shop with this sort of "treatment". Can't move the lever cap, without having to turn the bolt completely around four or five times. Chipbreakers mated to the bevel side of the iron, with enough junk under them to build a decent sized No. 2 pencil. Then, they leave it where a waterline can drip on it, or near an open window. Then just forgotten about until a yard sale day comes up.

Seen too many of these things. Then I get to clean up the mess...

[Pat Barry]

Curve along the lengthwise/longitudinal axis is mostly harmless and need not be flattened out. It's not like that iron is going to be longitudinally flat after you attach a cap iron to it, after all.

I agree - I was talking about the clamping causing the bow along the blade edge to be straightened a bit.

[Robert Engel]

Hi Steve -- I picked up this tip from David Weaver in one of his wood plane making videos. It just makes use of a chunk of 2x4 that allows you to bear down hard on whatever medium you're using to flatten. I use anything from diamond plates to 80 grit self stick sandpaper on a granite block. It really saves wear and tear on your fingers.I wouldn't recommend doing this especially on thinner irons like Stanley. I'll bet he is using fairly thick irons.

[Patrick Chase]

I agree - I was talking about the clamping causing the bow along the blade edge to be straightened a bit.

It takes a fair bit of force to flatten out bow along that axis. Just don't whale on it and everything should be ok IMO...

[Steve H Graham]

The irons I am fooling with right now are for a Stanley 57R and a 151. They are pretty thin. I like that jig thing. May try it.

I have a big block (4" square and over a foot long) of 1018 sitting around doing nothing. I should flatten one end side on the mill and see if it works for lapping.

[Steve H Graham]

Couple of interesting notes. To me, anyway.

The Harbor Freight iron I flattened a few days back wasn't concave. It was S-shaped. Had two curves in it, across the iron. Nice work, Harbor Freight. That is a hard act to follow.

Second thing: when I tried flattening the HF iron on the belt grinder, it seemed like there was some danger of abrading the sides more than the middle, just because belt grinders tend to do that. Yesterday I tried the belt grinder on a Stanley iron, and it seemed to work okay. I didn't push it, though. I went very slow, and I didn't have water beside me, so I didn't grind much.

[Patrick Chase]

Couple of interesting notes. To me, anyway.

The Harbor Freight iron I flattened a few days back wasn't concave. It was S-shaped. Had two curves in it, across the iron. Nice work, Harbor Freight. That is a hard act to follow.

Second thing: when I tried flattening the HF iron on the belt grinder, it seemed like there was some danger of abrading the sides more than the middle, just because belt grinders tend to do that. Yesterday I tried the belt grinder on a Stanley iron, and it seemed to work okay. I didn't push it, though. I went very slow, and I didn't have water beside me, so I didn't grind much.

I've also seen notably S-Curved or twisted plane irons from modern Stanley (a friend's plane iron that I volunteered to sharpen) and Qiangshang/WoodRiver. The QS/WR wasn't as bad as the Stanley.

Flattening on power tools requires a steady and controlled hand. If you rock or shift pressure at all you'll tend to grind a convex profile as you describe. Don't practice on your "good" irons, etc.

[lowell holmes]

Power tools work well, but I would use sandpaper on glass. Lay it flat on the bench with sandpaper up and hone away.
When you get through, the surface will be evenly flat. I imagine 120 grit will do the job.

[Mike Baker 2]

Flattening plane irons or chisel backs, I don't mess around. I use 60 grit, and just move up through the progression after I get to flat.
I don't own a grinder or belt sander, and I spent a lot of time with 120 grit doing this. My hands are less capable now, due to nerve damage and arthritis, so I don't fool with it. Lowest grit I can find to get to flat fastest.

[Steve H Graham]

Last night I put 60-grit on a diamond stone and worked my 151 iron while I watched Youtube. Barely accomplished anything! When you get close to being finished, you're cutting such a big area, it takes forever. You better believe I am going to start out with the hammer next time.

[Steve H Graham]

May God forgive me for not memorizing everything Paul Sellers says. The iron on my 151 is still not perfect. My new thing is to set a timer for 15 minutes, work on the iron, and then move on to something else. If I had known about the hammer trick, maybe this would not have been necessary.

I don't think it should be called "the hammer trick." Apparently, it's just the right way to fix plane irons, and people call it a trick because they don't know about it.

[Brian Holcombe]

Pretty sure he does that with a laminated iron, not a full steel iron.

[steven c newman]

I have....


IF you keep at it until it finally is flat, it may be a LOT thinner than it already was.....

[Patrick Chase]

Pretty sure he does that with a laminated iron, not a full steel iron.

I was wondering about that. Attempting Ura-Dashi on a single-piece hardened steel iron seems... risky to me.

[steven c newman]

Not really. BTDT.

[Steve H Graham]

Pretty sure he does that with a laminated iron, not a full steel iron.

A reader suggested he would have a problem if he tried to flatten a laminated plane, and here is how Sellers responded:


It is doubtful that anyone will actually come across a laminated Stanley blade though. I only came across one in my 50 years, so I doubt generally it is likely, but thanks for your input there.

https://paulsellers.com/2015/10/plane-questions-answered-bent-plane-irons/

[Patrick Chase]

A reader suggested he would have a problem if he tried to flatten a laminated plane, and here is how Sellers responded:

https://paulsellers.com/2015/10/plane-questions-answered-bent-plane-irons/

It's the other way around. You can do that more easily with a laminated blade because the "body" of the blade is unhardened and fairly tough (though obviously you have to avoid doing things that put too much stress on the weld. I think Brian has an article on the topic on his page).

[Warren Mickley]

It takes me a long time to prepare a plane iron for use, but I spend little time at it. The reason is I hardly ever do it. I use up a plane iron before moving on to the next. I have only ever owned five bench planes; only used nine irons. Amortized over the life of an iron, the time spent in preparation is trivial. The big waste of time is the constant desire to have a large fleet of planes with many irons.

Two of my planes are Stanley planes; both currently use laminated irons. Of my previous irons for those planes, one was laminated , one not.

Paul Sellers planes like someone without much experience. Might be more of a thickness planer and sandpaper kind of guy. I don't think he has learned to plane nearly as well as Brian Holcombe, who might be half his age, or David Weaver, who is a hobbyist.

[Brian Holcombe]

I am confused by the photo that says 'laminated' on the iron. Is he doing this to full steel irons?

Thanks Warren! I very much appreciate your comment!

[Chris Parks]

I had a plane iron and chip breaker that were really bent and using no hammer it took about five minutes to straighten them in a vice. Support the concave side with two parallels down each edge and put another down the centre of the blade on the convex side. Apply careful pressure along with guess work to the supports and the blade will come straight very quickly and no violence is needed. I used short pieces of 1/2" hexagon bar as the parallels for what it is worth. I tried Paul Sellers method and it didn't seem to get the results I wanted. If you have trouble positioning all the bits use a bit of hot glue to glue the supports to the blade or chip breaker.

[Michael J Evans]

Not to hijack the thread.
But since I've begun using hand planes 6 months or so, everything I've read says you have to flatten and polish the back and that it's a once in a lifetime thing.

If that is the case then why have all 5 of my vintage planes been out of flat, and needed major time to being back to a polished edge? A couple of the woodies are real old and a couple of the Stanley early 1900's and a blue one.

Was the knowledge or equipment just not there a 100 years ago (or more) to flatten the back? And even if it was how come the the iron has went out of flat?

I'm not trying to go against the grain on this one and have flattened all of my irons. It's just bugged me everytime I spend an hour doing it. All I can wonder if why was this back good enough for the old craftsman.

[Warren Mickley]

Not to hijack the thread.
But since I've begun using hand planes 6 months or so, everything I've read says you have to flatten and polish the back and that it's a once in a lifetime thing.

If that is the case then why have all 5 of my vintage planes been out of flat, and needed major time to being back to a polished edge? A couple of the woodies are real old and a couple of the Stanley early 1900's and a blue one.

Was the knowledge or equipment just not there a 100 years ago (or more) to flatten the back? And even if it was how come the the iron has went out of flat?

I'm not trying to go against the grain on this one and have flattened all of my irons. It's just bugged me everytime I spend an hour doing it. All I can wonder if why was this back good enough for the old craftsman.

The "old craftsman" who knew his way about a plane was dying off in the 1840's not the 1940's. I used to talk to old craftsmen forty and fifty years ago; it wasn't hard to surpass their knowledge of planes. The plane you buy at the flea market was more likely purchased by home owner, handyman or carpenter than someone who wanted a fine surface on figured walnut.

We flatten the back so that we have a flat section near the edge for polishing the back side and finishing off the edge. We like enough flattened so that we get a good purchase on the stone for repeatability. Although when sharpening we do the bulk of abrasion on the bevel, the back needs some small amount of abrasion to take care of small scratches as they occur.

Because we abrade the back near the edge, it gradually gets out of flat with the rest of the iron around the slot. This is of no consequence. We just need it flat in the area near the edge.

[Steve H Graham]

The only thing that seems clear is that I have done it the hard way.

[Malcolm Schweizer]

When I finally get around to building it, I will post a thread, but I have designed and have all the parts for a 12" lapping wheel using a 1/4hp Baldor motor and a wheel from a disc sander with a diamond wheel mounted to it. I have to finish my never-ending workbench project and build a life-sized dinosaur for a children's museum first. Seriously.

[Steve H Graham]

I am confused. Shouldn't a children's museum display life-sized children?

[steven c newman]

363010
This iron from an Ohio Tool Co. 0-7.....was bowed badly in length...followed someone else's "advice" to use a vise to bend it straight...
363011
Did NOT turn out nicely....had a friend with a good wire welder, and the shop tools needed, set it up, weld it back up, clean it up. I honed, flattened and have been using the repaired iron ever since. No, it is not a laminated iron, nor a tapered one..
363012
However, these two 0-35s use the laminated, and tapered irons.
363015
YMMV...

[Jim Koepke]

Gosh it has been eight years since posting "Fettling a Plane, From Junker to Jointer":

http://www.sawmillcreek.org/showthread.php?114373-Fettling-A-Plane-from-Junker-to-Jointer

Post #28 in the thread has an image of a cap iron being worked on a Veritas Mk.11 Power Sharpening System:

363016

This is also a great way to quickly work the back of a blade. Most of the time taken is letting the blade cool. In my days of fettling a bunch of planes it was quicker to work with a few at a time so one blade could be worked as others cooled.

Johnny Kleso built his own with instructions on his web site:

http://www.rexmill.com/sharpening/MKIII/MKIII.html

Besides this my best back flattening strategy is a four foot hunk of granite purchased from a monument maker (gravestone carver) with a long strip of abrasive adhered to it. Here it is without abrasive:

363017

Dang it has been awhile since the shop was that clean.

jtk

[Chris Parks]

363010
This iron from an Ohio Tool Co. 0-7.....was bowed badly in length...followed someone else's "advice" to use a vise to bend it straight...
363011
Did NOT turn out nicely....had a friend with a good wire welder, and the shop tools needed, set it up, weld it back up, clean it up. I honed, flattened and have been using the repaired iron ever since. No, it is not a laminated iron, nor a tapered one..
363012
However, these two 0-35s use the laminated, and tapered irons.
363015
YMMV...


Mine turned out OK. I have aslo used a Worksharp with diamond plates but when I go back to the stone from the WS it shows a different grind pattern which I find puzzling.