# Hand Planes...a Design Limitation?



## 33706 (Mar 5, 2008)

*Something is inherently wrong with the design of the typical handplane!* It just occurred to me, as I set up a new set of cutters on my antique jointer, that the bed of a hand plane should be "stepped" as is the table of a jointer! Think about it! Assuming that a plane shaving is approximately .005 inch thick, this means that the toe of a handplane is mostly elevated above the surface of the board. The only two areas of contact between the sole and the board is that area just ahead of the mouth, and the far back end of the heel. (This also explains why experts often say that flatness is over-rated). This explains why it's hard to keep a #3 or #4 exactly square to the sides, with that bump-out for the rear tote making it unstable. 
So… what if somebody milled a plane so that the toe, the leading edge, was .005 HIGHER than the aft section behind the blade? Imagine, the cutter FLUSH with the sole behind it. This way, the entire sole would contact the board, ahead of the cut, AND behind it.
Any thoughts? Could somebody do a Sketchup or CAD thing to illustrate the deficiencies in a typical handplane and post it here?


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## donwilwol (May 16, 2011)

Then you'd always have to start the plane off the board or the cutter would never touch. ( like you do a jointer) think what a pain that would be.

Easiest way to test your theory that I don't think will work: modify a transitional.


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## 33706 (Mar 5, 2008)

good idea, Don! To have 100% contact with a recessed toe ahead of the cutter is the concept I'm thinking of.


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## rance (Sep 30, 2009)

In my unprofessional opinion, the shavings are supposed to be nearer to 0.001", not 0.005". I'm not a hand plane guy though.

What Don said, stick some of that UHMW tape behind the blade on the sole and adjust your blade to the thickness of that tape.


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## lab7654 (Mar 31, 2012)

Glad I'm not the only one this bothers. I don't personally use hand planes but the design they have often bugs me…


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## donwilwol (May 16, 2011)

If you guys are going to make my Stanley's obsolete after a couple hundred years, I'll need to know ahead of time.

;-)


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## Mosquito (Feb 15, 2012)

The other issue, is that theoretically you'd have to use a Rabbet plane… because otherwise the width of the blade would be less than the width of the plane. Unless you only did this adjustment to the center of the sole…


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## 33706 (Mar 5, 2008)

Wow, thanks, *Rance!! *That's an absolutely perfect rendition of what I meant! I just took some random curls off the floor and trash can, each one I meaasured was between .004-.006. Heh, I don't do 'money shots' so I go as deep with the cutter as I can. *Mosquito*: Oh yeah, true! If the sides of the mouth were milled to the same height as the nose, it shouldn't be a problem. *Lab*: Thanks for the words of encouragement!
To put this all another way, visualize a bullnose plane with the cutter edge front and center…then visualize adding a toe set to the height of the unplaned board.
*Don…*don't worry, your planes will be safe for another thousand years. Though they might be found buried under a Pompeii-like excavated civilization, LOL!


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## renners (Apr 9, 2010)

I agree with the theory, take a look at the depth adjustment of any electric hand planer, the depth of cut is adjusted by raising or lowering the part of the base in front of the cutters. 
But in the real world, hand planes work, have worked well for centuries, so if it ain't broke…


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## Mosquito (Feb 15, 2012)

You would have to go beyond just the the mouth. You'd have to go down the entire length of both sides, to bring it in just narrower than the blade. Otherwise the blade wouldn't clear the wood in front of the rear section of the plane body.


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## Mosquito (Feb 15, 2012)

This would also eliminate the ability to angle the plane to effectively cut with a skew… Interesting concept for something to only use as a jointer, though.


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## Rob_G (Mar 25, 2011)

The sides of the plane sole are wider than the blade, so the back side of the sole doesn't "fall" into the new groove as it's cut because the back section oft the sole is wider than the cut. Having a raised area on the back hald of the plane sole would prevent using the plane at an angle.


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## vipond33 (Jul 25, 2011)

I actually tried this out on a No.5 about 30 yrs. ago with a machinist friend. He put it on a milling machine and took it down .002. For the reasons given above it did not work. We could have anticipated the result if we were thinking straight but I think the idea came after too many brewski's. The next day we soberly milled off the rest of the plane. 
BTW, just out of curiosity Rance, lately you seem to know a lot about hand planes. Is it time for you to come out of the backer board closet?
gene


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## 33706 (Mar 5, 2008)

*Mosquito:* Ah, very astute!! Now I get the rabbet plane idea mentioned above too. Yes, a prototype would have left two jet trails of original height left behind it! I'm grateful for everyone's participation here.

I had been visualizing a 3/4" board in a vise, not even considered machining a wide board, wider than the plane body! Thanks, all!


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## Mosquito (Feb 15, 2012)

Gave me an idea though… not sure it would work, but it's an idea none the less…

Instead of just a straight recess on both sides, what if you tapered the recess into a V that was blade width at the mouth, and tapered down. That would allow you to skew the plane a little still, if it was to be used for face planing… Just thinking out loud here lol


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## Mosquito (Feb 15, 2012)

This is what I was talking about… exaggerated for easier viewing


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## rance (Sep 30, 2009)

You're welcome PK.

Obviously for a wide board it would not work, but for an edge, why not?

Gene, I only know one thing about hand planes. I just play a handplane know it all here on LJ.  And I like it here in my closet. It makes me feel safe.


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## mochoa (Oct 9, 2009)

Interesting convo, you know japanese planes take the opposite approach from what I understand, the sole behind the blade is recessed and doesn't actually touch the wood.


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## Loren (May 30, 2008)

Operator error would negate the advantage of a stepped sole. If 
the operator lets up on pressure at any point I suspect the next
cut would be problematic and then compound errors would ensue.

Some chamfering hand planes have stepped soles I think. I've
never used one or examined them closely.

That said, I have never used a super-surfacer (fixed blade
planer) and I don't know if they have adjustable tables.


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## Sylvain (Jul 23, 2011)

I have read the same thing as Mauricio about Japanese planes.
http://giantcypress.net/tagged/plane/page/5
http://giantcypress.net/post/3874908014/japanese-jointer-plane-sole-configuration

Hand planes and planers are not supposed to deliver a flat surface (in the mathematical meaning of it); at least not in a single pass. 
How could they? They are relying on the rough or unfinished surface of the board for guidance.

To have a flat surface, the movement of the blade relative to the board must be guided by a flat reference surface not by the board itself.
The solution is 
a milling machine like :
http://lumberjocks.com/projects/71687 (the last one of its kind posted here but there are others);
or attaching the rough board on a flat sled and put it through a thicknesser.

But then do we need mathematically-perfect flat boards?


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## donwilwol (May 16, 2011)

I've only been serous about hand planes for a few years now and would have been considered a power tool guy, so I've tried every possible angle to flatten the top of large pieces. Belt sanders, router jigs and the like. They all work, but unless you make a permanent solid router jig that takes up a lot of room, there is nothing that works better than a good set of hand plane.

On paper the process looks long and tenuous, but in practice, I think it's quicker and easier than all the others.

FWIW, David Moore has a pretty decent article in this months fine woodworking on how to do it.


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## Sylvain (Jul 23, 2011)

Thinking about it,
the handplane is cutting the crest of the waves.
The longer the sole of the plane the longer the distance between two crest.
The setting must not be that agressive that the crest would be replaced by trough.
The fact that the blade is not in the middle of the sole probably participate to the progressive damping of the waves.
You will note that on Japanese planes the blade is not in the middle either.
Would anybody experiment a handplane with the blade exactly in the middle of the sole?


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## rance (Sep 30, 2009)

>"stick some of that UHMW tape behind the blade on the sole and adjust your blade to the thickness of that tape."

I've got one for you PK. Instead of the UHMW tape, just use 220 grit sandpaper. That way you do your planing and sanding operation in one fale swoop. 










See, I told you I didn't know anything about handplanes.


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## Smile_n_Nod (Jan 20, 2011)

The book "The Essential Woodworker" by Robert Wearing discusses this topic. He only mentions that the cost to build such a plane would be prohibitive-he says nothing about any deficiencies in the concept itself.


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