Really stupid question about hand planes.

[Sawyer]

Re; the 10 shavings = a hump; I think this should only be a problem if the plane is by some sort of machine. In practice, it's counteracted by the fact that the plane is held by a human being . It's just a question of technique, surely?

 

[bugbear]

Well, there's a lot for me to read here. When I asked the question I was explicity thinking of the situation where one is trying to obtain a straight edge for jointing boards, so I was picturing the workpiece being narrower than the blade. However, the replies have probably covered this situation as well as most others.
It'll take me a while to read and digest all of this, but in the meantime, thanks to everyone who has responded.

John

The question of how to make a flat surface using a plane has been (loudly) answered.

No-one has responded your interesting point about "flat soled" hand planes versus "step-soled" machines.

BugBear

 

[David C]

BB,

I thought I had answered it !
Machine planers have the correct geometry to produce flat surfaces, bench planes generally do not. Technique and stop shavings are required.

David Charlesworth

 

[GazPal]

Forgive me for having to ask, but I can't get my head round this.
On a power planer, even a hand-held one, the table, or the sole? in the case of a hand-held electric planer, is at a different height in front of the cuting edge compared to behind the cutting edge. Indeed, if I want to set up my router table for jointing, I have shims that move the outfeed fence relative to the infeed. This makes sense to me.

In the case of a hand plane, with a flat sole?(if I have the terms right) I would have thought that the piece being planed would end up with a slight curve, as the back end of the plane dropped down onto the section that had already been shaved.
Why is this apparently not a problem? Is the effect too small to matter, or am I missing something?

John

The problem encountered with hand planing is/can be avoided via practice at planing straight and true and adopting techniques already described by others. A great deal then becomes second nature and is done without putting much - if any - thought into the process involved (Hence the possible lack of many answers to your question), but you'll tend to find less of a problem planing straight and true when using increasingly minimal blade/iron set and taking fine shavings as the surface being trued is tamed.

 

[Jacob]

BB,

I thought I had answered it !
Machine planers have the correct geometry to produce flat surfaces,.

Hand held power planers cut a trench and could in theory precisely remove parallel trenches to flatten a surface, but only if it's flat to start with :roll: . But they tend not to be, and power planers are really difficult unless just removing stuff quite roughly - a powered scrub plane.

.the bench planes generally do not.

It makes no difference and they are a lot easier to use, but slower!

Technique and stop shavings are required.

David Charlesworth

Technique yes, for both. Any effort to remove high spots is effectively a "stopped" shaving i.e. it starts and/or stops within the length of the workpiece.

 

[Cheshirechappie]

Well, there's a lot for me to read here. When I asked the question I was explicity thinking of the situation where one is trying to obtain a straight edge for jointing boards, so I was picturing the workpiece being narrower than the blade. However, the replies have probably covered this situation as well as most others.
It'll take me a while to read and digest all of this, but in the meantime, thanks to everyone who has responded.

John

The question of how to make a flat surface using a plane has been (loudly) answered.

No-one has responded your interesting point about "flat soled" hand planes versus "step-soled" machines.

BugBear

I can't remember where I saw this, but someone reported checking over an old wooden rebate plane, and finding that the sole ahead of the blade was a hair above the sole behind the blade, though both 'halves' of the sole were flat. Just like a machine planer, or power hand-planer.

I think it's probably fair to say that as either the planemaker or the person who 'adjusted' the sole thusly is more than likely making shavings in the great workshop in the sky, we won't know if this was deliberate or a happy accident, but it would be interesting to know how it affected the plane's performance, if at all.


Just a thought to ponder on - how flat is 'flat'?

 

[Digit]

how flat is 'flat'?

The question I posed earkier. Flatening should be that which is required for the plane to work, beyond that is plain masochism!

Roy.

 

[Alf]

I can't remember where I saw this, but someone reported checking over an old wooden rebate plane, and finding that the sole ahead of the blade was a hair above the sole behind the blade, though both 'halves' of the sole were flat. Just like a machine planer, or power hand-planer.

I think it's probably fair to say that as either the planemaker or the person who 'adjusted' the sole thusly is more than likely making shavings in the great workshop in the sky, we won't know if this was deliberate or a happy accident, but it would be interesting to know how it affected the plane's performance, if at all.

That reminds me - doesn't the #75 bullnose have the nose piece higher than the rest of the sole? Or so I've seen reported (often). Reported even more often is what an utter stinker the #75 is to use. Connection?

I know we've had the flat hand plane/stepped machine bed discussion before, but blessed if I can find it. However, I do seem to recall that someone observed that wouldn't you have to have a range of steps in the plane sole, to cover the range of shaving thicknesses? The discussion should be in the archive somewhere - if you can find it.

 

[Cheshirechappie]

how flat is 'flat'?

The question I posed earkier. Flatening should be that which is required for the plane to work, beyond that is plain masochism!

Roy.

Yes - I agree.

The degree of flatness required is that which is appropriate to the job in hand. A few posts ago, Jacob mentioned that a slightly convex handplane sole would give you more control, and I think he's onto something there (though the convexity would have to be within sensible limits, obviously; otherwise you have a compass plane). We know that concave is undesirable, and a 'truly' flat sole gives an effectively convex plane anyway - the three fixed points of toe, heel and tip of cutter will not be a straight line, because if the sole is flat, the cutter must protrude below it or it wouldn't cut.

Another factor is that both the plane and the workpiece will deflect slightly under cutting forces. Indeed, a plane will deflect slightly under it's own weight, but the deflection is unlikely to be significant compared to the other factors involved in planing a piece of wood to a workable flatness. Also, planing technique has evolved to negate the negative factors.

Actually, there's an interesting parallel from the world of engineering. To file a surface flat, you don't use a file that's flat; a so-called 'Flat File' actually has a very slight belly in it - you can see this if you sight down the length of the file. So if you want to take off a very slight hump to leave a workpiece flat, you use the bellied 'flat file' with a bit of finger pressure on the area that needs attention, and the bellying of the file lifts the rest of the cutting surface very slightly clear of the surface. A 'Hand File' is flat, but won't file flat - the best you can do is to leave the work slightly convex. (If you want something REALLY flat, you can't do it by filing alone. You'll need to follow up by scraping to a surface plate, or resort to some very precise grinding or honing equipment.)

 

[AaronWright]

if i am going to join 2 boards together the first thing I do is sight down the board to get a mental picture of where any high or low bits are. Lets say there was a couple of high bits I would just take few shavings off these bits so they wont cause any problem for when u start to straighten out the board. When straightening I would just take a a continous shaving front to back. Making sure to keep the plane square. then on the next peice i would do the same .Then I would try them together to see what areas needed tweeking Then all i do is make the boards fit each other as long as the fit each other and no gaps youve done it right
At times you can worry about getting it perfect and all you end up doing is going past the place when u had it right and make it worse

 

[AndyT]

That reminds me - doesn't the #75 bullnose have the nose piece higher than the rest of the sole? Or so I've seen reported (often). Reported even more often is what an utter stinker the #75 is to use. Connection?

It's something Patrick Leach says ( http://www.supertool.com/StanleyBG/stan10.htm#num75) -

"The section of the sole ahead of the iron is not co-planar with the sole behind the iron. The plane is purposely made this way to assist it with its cut (you guys what owns the 'lectrical jointahs should know why the plane's sole is the way it is) so there's no need to practice sole lapping on it. "


- but that certainly is not true on my one. Maybe it's his equivalent of the fake streets drawn by map makers to prove that someone has copied their work - he certainly gets quoted on eBay without attribution often enough!

 

[Alf]

I had a feeling I'd seen it elsewhere though, several times - I tend to disregard pretty much all of Blood & Gore as a primary source of anything, 'cos he's so damn rude about the combi planes. :lol:

 

[Jacob]

..........
Actually, there's an interesting parallel from the world of engineering. To file a surface flat, you don't use a file that's flat; a so-called 'Flat File' actually has a very slight belly in it - you can see this if you sight down the length of the file. So if you want to take off a very slight hump to leave a workpiece flat, you use the bellied 'flat file' with a bit of finger pressure on the area that needs attention, and the bellying of the file lifts the rest of the cutting surface very slightly clear of the surface. A 'Hand File' is flat, but won't file flat - the best you can do is to leave the work slightly convex. .......

Interesting. Makes sense.
I often wonder about the weird obsession with flattening chisel faces. Never made sense to me. If you want to pare a flat surface the chisel face has to be convex to some extent.
You can see the problem here http://www.youtube.com/watch?v=cOvkNuwO_YM
Rob Cosman doing a commercial for a very expensive diamond plate burbles on knowingly about flat faces etc but then completely fails to pare the end grain of his sample. He cuts a notch instead. Not that he seems to notice this himself!
Hilarious!

 

[David C]

I fear the joke is on you, Jacob.

 

[jimi43]

On the subject of stepped front sole, I noted that my Mosley rebate plane was like this in this thread (CLICK PHOTO)



Each separate part of the sole is relatively flat but they are stepped as you can see from the photo.

The shavings are the best I have ever had from a woodie so clearly this stepping is intentional and works....

Note also that the edge of the iron is level with the rear sole (only slightly protruding) and has maximum support.

Jim

 

[MickCheese]

..........
Actually, there's an interesting parallel from the world of engineering. To file a surface flat, you don't use a file that's flat; a so-called 'Flat File' actually has a very slight belly in it - you can see this if you sight down the length of the file. So if you want to take off a very slight hump to leave a workpiece flat, you use the bellied 'flat file' with a bit of finger pressure on the area that needs attention, and the bellying of the file lifts the rest of the cutting surface very slightly clear of the surface. A 'Hand File' is flat, but won't file flat - the best you can do is to leave the work slightly convex. .......

Interesting. Makes sense.
I often wonder about the weird obsession with flattening chisel faces. Never made sense to me. If you want to pare a flat surface the chisel face has to be convex to some extent.
You can see the problem here http://www.youtube.com/watch?v=cOvkNuwO_YM
Rob Cosman doing a commercial for a very expensive diamond plate burbles on knowingly about flat faces etc but then completely fails to pare the end grain of his sample. He cuts a notch instead. Not that he seems to notice this himself!
Hilarious!

Jacob

Am I missing something? I am sure he meant to do that, he even mentions cutting downwards. Are you just being deliberately obtuse? [-X

Mick

 

[Digit]

I've just been out to check two of mine Jim and one is like yours and 'tother isn't.
I suspect that it is wear.
This business about flatness is such that I don't even think about it unless my planing goes up the creek.

Roy.

 

[Jacob]

Could be just wear?
In use the pressure is on the front end which could cause it to wear faster. If it was deliberate then the difference would have to be the same as the thickness of the shaving or it'd be rocking about from one bit of sole to the other, just like a worn out plane with a convex sole. Which incidentally can work perfectly well - you are working to the line, not to a depth determined by the kit as you would with a router.

 

[Jacob]

.....

Jacob

Am I missing something? I am sure he meant to do that, he even mentions cutting downwards. Are you just being deliberately obtuse? [-X

Mick

But what is the point of his demo? You could do that notch with any sharp chisel even with a back bevel or a totally convex "belly". Sharp pen-knife for that matter.
He doesn't explain why you need to flatten and polish the whole back. Carvers don't do that even though they need a clean chisel finish and total control.
Being deliberately obtuse? More like RC being inadvertently pointless.

 

[Digit]

I flatten the backs to give me more control, it acts as a register.

Roy.