Hand plane sole flatness?

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If you make an infill, you'll find you wish you had a file. The mild steel just doesn't yield much to the paper.

If you get an old infill that's horribly out of flat, the same. They'll be steel and hand lapping won't do much. Common wisdom would suspect either the old ones aren't very flat, or they're all very flat. I found most of them to be very flat, but I did get one norris that was for some reason horribly out of flat. Fortunately, it was a smoother, so I lapped it, anyway, but it took a while and ate paper. If I'd have figured out the filing ahead of time, it would've taken a lot less work.

Why is this flatness important? At some point in the future, I'd like to sell a few infills (way in the future), but I'm not going to sell an infill that is less flat than a lie nielsen plane. It doesn't really have much to do with function, but the video I put up a couple of weeks ago continuing to joint an edge without putting a hump in it does rely on a plane bottom to be flat or reasonably close to it (lapping by hand has always been good enough for me).

What we're left with, though, that the above method would be useful for is spot removal with a file (the file type is important, you have to be able to use the end and flex the file a little bit) and lapping, as an iterative process. I have a lot of old planes and not a single one of them is square. I do have planes that are square, but none of them are old bench planes. My perception from actual use is that if they're reasonably close, you can still use them to shoot without any issue, but I'm sure there are some folks who won't believe that.

There are a lot of things that we do that we don't *have* to. I'm not going to build infills to sell for $300, so this is something that I'm going to have to take care of, and I have zero interest in buying metalworking machinery and then having subsequent plane designs that look like they were made to fit my metalworking machinery.

Not at all advocating any of this for someone who wants to buy a bailey pattern smoother of some brand and use it. Lapping the plane sole is just fine for that, and a given plane may not even need anything at all, even for smoothing (and very finely).

there was also a rash here of people sending off their old planes to be surface ground by a guy and paying at least one way shipping, so they were out of the use of their planes and out of something like $100, and putting that into a plane where they'll never get their money back. If they got their plane back and the machinist doing the work left the toe and heel two thousandths proud of the mouth, they'll never be able to do what I did in the video that I showed, and it will materialize in facing lumber, too - that's a real pain.
 
OK making them is another problem. Most of us (and the OP) are just talking about remedies for a supposedly finished plane.
 
If you have a perfectly square sided plane and you remove the iron for honing and replace it slightly out of square it doesn't matter that the actual plane is perfect - conversely you can allow for a slight deviation from a right angled side by skewing the iron very slightly. I was taught at school (50 years ago) when shooting to always check the work and not presume the plane was perfect. I think people put too much importance on dead 90 degree sides.
 
phil.p":1uss89jt said:
If you have a perfectly square sided plane and you remove the iron for honing and replace it slightly out of square it doesn't matter that the actual plane is perfect - conversely you can allow for a slight deviation from a right angled side by skewing the iron very slightly. I was taught at school (50 years ago) when shooting to always check the work and not presume the plane was perfect. I think people put too much importance on dead 90 degree sides.
Yep. The forgotten art of looking at stuff rather than relying on tools and gadgets.
 
Jacob":2rg0lcin said:
Yep 80 grit wet n dry. Flooded wet with white spirit. Cheapest paper backed wet n dry will lie very flat in a pool of white spirit (or water) on a suitable base (I use my planer bed) and not need sticking down or anything.
When you have nearly finished do it to and fro against a bit of a fence (lath clamped on ) so you get straight lines parallel to sides
...

Not sure what 'lapping' is exactly
As woodworkers use the term, it's exactly what you just described. You're lapping. Well done.

BugBear
 
D_W":3k5yprkd said:
there was also a rash here of people sending off their old planes to be surface ground by a guy and paying at least one way shipping, so they were out of the use of their planes and out of something like $100, and putting that into a plane where they'll never get their money back. If they got their plane back and the machinist doing the work left the toe and heel two thousandths proud of the mouth, they'll never be able to do what I did in the video that I showed, and it will materialize in facing lumber, too - that's a real pain.

I got my local tool works/saw doctors, North London Saws (5 minutes walk from my house) to grind my plane soles and square one side, £25 to set up the machine and do one, £5 each for the others (I think they did 5, can't remember it was a few years ago). It's not a service they normally provide but I know them quite well and thought I'd ask and they obliged. My thinnest feeler is 0.05mm (roughly 2 thou) and I can't fit it under my engineers straight edge on any of the planes and a couple were totally bananas. I agree that squareness is not necessary, but for £5 why not? I agree that $100 a plane would not be worth it.
 
I think at that price, I'd have them do all of mine.
 
Paddy Roxburgh":3erthm4z said:
..... I agree that squareness is not necessary, but for £5 why not? .....
Because the Stanley Bailey design has a very efficient lateral adjuster to square the blade for a shooting board. Having a square side makes no difference - you still have to square the blade.
 
Jacob":164q54wt said:
Paddy Roxburgh":164q54wt said:
..... I agree that squareness is not necessary, but for £5 why not? .....
Because the Stanley Bailey design has a very efficient lateral adjuster to square the blade for a shooting board. Having a square side makes no difference - you still have to square the blade.
Interesting idea.
If the side isn't square to the sole, you can EITHER have the blade parallel to the sole, giving a cut of uniform thickness, OR you can have the blade square to the side, but you obviously can't have both.

Tapered shavings are not helpful to good shooting. Better to set the blade parallel to the sole in the normal way, using the lateral adjuster, and bung a shim (bit of cardboard!) under the workpiece to correct squareness.

BugBear
 
Jacob":7ed846yr said:
phil.p":7ed846yr said:
If you have a perfectly square sided plane and you remove the iron for honing and replace it slightly out of square it doesn't matter that the actual plane is perfect - conversely you can allow for a slight deviation from a right angled side by skewing the iron very slightly. I was taught at school (50 years ago) when shooting to always check the work and not presume the plane was perfect. I think people put too much importance on dead 90 degree sides.
Yep. The forgotten art of looking at stuff rather than relying on tools and gadgets.

That's why I don't get too hung up about having planes and such like prepared to spaceflight engineering standards. The tool, however perfect, will be in the hands of a human being, who will then need to correct his own user-imparted imperfections by the time honoured methods.
 
Sawyer":341lssbk said:
Jacob":341lssbk said:
phil.p":341lssbk said:
If you have a perfectly square sided plane and you remove the iron for honing and replace it slightly out of square it doesn't matter that the actual plane is perfect - conversely you can allow for a slight deviation from a right angled side by skewing the iron very slightly. I was taught at school (50 years ago) when shooting to always check the work and not presume the plane was perfect. I think people put too much importance on dead 90 degree sides.
Yep. The forgotten art of looking at stuff rather than relying on tools and gadgets.

That's why I don't get too hung up about having planes and such like prepared to spaceflight engineering standards. The tool, however perfect, will be in the hands of a human being, who will then need to correct his own user-imparted imperfections by the time honoured methods.

I'd agree that it's rather pointless taking things too far, but many of us have found ourselves with planes having warped castings, rendering them somewhat less than effective at what they're supposed to do. We then have the choice of either replacing the plane altogether, or rectifying the fault to the point where the plane will actually do what it's supposed to. (Sides square to sole is nice, but not essential, within reason; sole flat enough to work properly is essential, though.)
 
Jacob":2enyw8g8 said:
Paddy Roxburgh":2enyw8g8 said:
..... I agree that squareness is not necessary, but for £5 why not? .....
Because the Stanley Bailey design has a very efficient lateral adjuster to square the blade for a shooting board. Having a square side makes no difference - you still have to square the blade.

That's true, but it works a little better if the blade is projected evenly from left to right. It's not "dire", to use the word above, it just works a little easier if it's dead on.
 
The worst kind of sides are the ones that curved in their height.

These will not sit stable on a surface.

I suspect that many of these were reasonably flat in the beginning, but dressing on abrasive paper makes them round.

The best policy for a flat side is to use a small block , aiming for even coverage.

David Charlesworth
 
David C":3gq1djd9 said:
...
... dressing on abrasive paper makes them round.....
Not if you use thin paper backed wet n dry in a pool of white spirit on a flat surface. I use a planer bed. Once well soaked the paper stays stuck down very flat under capillary action alone. You can put two A4 size pieces end to end - with a gap if you wanted to just do the ends of a long one. Helps if you store the paper flat between boards when not in use.
Cloth backed wet n dry no good for flattening, nor stuck-down paper-backed, neither will be as flat as the method described above.
NB wet cuts loads faster and lasts much longer than dry, so its win, win!
 
stuck down paper backed is superb for flattening. PSA roll, it's hard, and I personally like the heavier paper weight a little better, but lately it costs 3 times as much here.

A PSA porter cable roll (80 grit) of 4 inches by 10 yards is about $12 right now. My favorite Mirka gold is up closer to $30 with shipping. I don't know what the weight is in rolls, but if it's comparable to papers, the porter cable roll is like b weight and the mirka is like F. Either one yields about the same flatness with the same user (I measure - I don't need to, but I am putting away skills to make planes by hand at some point in the future).

The user pretty much determines how much damage the lap will do to a plane that should've been close to flat. A good user will have toe proud of the mouth by half a hundredth maybe on a plane that needed heavy work. A bad one, much worse (I have received planes that have been overcooked). A good user will also avoid lapping more off the top of a plane cheek than near the sole, but a bad user will not and will not notice that depth is removed fastest at the top of the cheek. A bad user will make a rocker like david describes, but it's not dependent on paper - only the very ends of the plane will show evidence of loose abrasives that dub - the center majority of a plane will be unharmed by a poor choice of paper and affixing methods.
 
D_W":1ub5xanu said:
stuck down paper backed is superb for flattening. PSA roll, it's hard, and I personally like the heavier paper weight a little better, but lately it costs 3 times as much here. ....
But it's never going to be as flat as thin paper wetted on a flat surface, which is also cheapest. Wet also cuts faster and is easier to keep clear of swarf (rare earth magnet) which means it lasts longer.
Summary; it's flattest, fastest, cheapest and last longest. :lol:
 
The standards people are aiming at also vary; I saw a plane sold on eBay a while back, where the seller claimed to have flattened the sole. There were helpful photographs.
flat.jpg

:D

BugBear
 

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If I was in the process of flattening that sole I'd think I was very close. Just a touch more to get the front of the mouth right and I'd leave it at that.
 
G S Haydon":j8yv4b4b said:
If I was in the process of flattening that sole I'd think I was very close. Just a touch more to get the front of the mouth right and I'd leave it at that.
The nasty thing about lapping is that as the flat area grows, the process slows.

When you start, you think "GREAT; this is going really well; the little flat spots are growing really fast, I should have done this ages ago"

An hour later, the sole is mainly flat, with (probably) a dip in front of the mouth. And that little dip just refuses to come out. Because you don't get to raise the dip, you have to lower the whole sole (obviously). And you think "that's near enough ..."

It's frustrating.

BugBear

N.B. - the dip in front of mouth in the photo is fairly small, but we don't know how deep it is...
 
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