Sole flatness for a #7

[John Densmore]

HI All,
I have a number 7 that has a concave sole. Near the mouth the gap is 1/32", maybe slightly more. The largest gap is a few inches behind the mouth and might be 3/64". I have sanded my #4. and 5's down so that the bottoms are dead flat. Should I do the same for the #7? If I do need to lap it, I think it is going to take a good amount of time with the amount of material that needs to be removed.

Thanks

[Jim Koepke]

You have a few options.

One would be to send it off to Table Saw Tom, aka Tom Bussey, and have him do it on his set up.

You could lap it like was done with your other planes.

Another method, if you can mark and remove the high spots before lapping it might save time and effort.

The problem with this kind of concavity is there can be a slight flex to the sole and it will be near impossible to do good work with it.

jtk

[Joe Bailey]

The first question is: Does it work as is?

[Paul Sidener]

That is a lot of material to remove, how thick is the sole of the plane? How old is the plane and what is it worth to you? If it has a lot of sentimental value, I would probably leave it alone. If it was something I picked up off of ebay for around $30, I might try and lap it.

[Reinis Kanders]

Has anyone ever tried to lap planes using disc sander?

[Keith Mathewson]

I took mine to a machine shop which has a surface grinder. Flat sole and flat sides which are now 90 degrees to the sole. All for around $50.

[Jim Koepke]

The first question is: Does it work as is?

Very good question. If it works, don't try to fix it.

Has anyone ever tried to lap planes using disc sander?

Yes a belt sander has also tasted the belly of some of my planes. Both require attention to what is going on. Both can do as much damage as careless hand lapping, only faster.

With a slight concavity in the middle of a long plane, it could be caused by a belt sander.

Lately I have also read of some who like a jointer to have a concave sole. The theory is one doesn't plane the ends of a piece until the plane stops cutting in the middle. Then take full passes until the plane takes a full length shaving. Maybe next time a long plane with a concave sole comes my way this method might get a trial run. Who knows, there is a #8 waiting for me to get a round tuit. I don't think I have looked a the sole on that one yet.

jtk

[Stew Denton]

Hi Reinis,

I used to use a disc sander quite a bit for various things. Based on that experience, I would say that it shouldn't be used to try to flatten the bottom of a plane. A disc sander is not a type of sander that gives fine control, and to flatten a plane bottom is a precision type of job. Secondly, metal is tough to remove without some pretty aggressive stuff. So, if you have a disc sander that is aggressive enough to remove much metal in a reasonable time, the control issue will become a problem, and my fear is that you can dish a spot, or create some other type of problem just as quickly as you can fix the original issue.

That is why folks use dead flat plates to try to flatten the sole of the plane. You can use fairly aggressive stuff, and still only try to remove material from the correct spots where it needs to come off, not where you accidentally go.

Tom Bussey has mentioned that he has flattened a number of plane bottoms where someone had previously tried to do it by hand, and their efforts had actually made the plane worse. Tom uses very good equipment to flatten the bottom of planes, and he did one for me, and he is recognized on this board as one who does extremely good work. He is extremely knowledgeable about such matters. I know that there are points of disagreement about this subject, among more than one on this board, who all have forgotten more about this subject than I will ever know.

That said, I don't think I would touch the bottom of one of my good planes with a disc sander in the effort to flatten it.

Stew

[Judson Green]

I think you'd be surprised how quickly a file will work.

[Kent A Bathurst]

One would be to send it off to Table Saw Tom, aka Tom Bussey, and have him do it on his set up.

My perspective: This is not a lifestyle for me [fettling planes]. It is an annoyance. Life is too short.

Tom does fantastic work, at prices I cannot comprehend. He is happy, so I am happy, but still..........

I have a stunning K7C I bought from him.........

[steven c newman]

Hmmm...that supposed concavity is from all those years of wear, from the plane doing it's job,

A #7 is not usually a "shooting" plane. 90 degree sides aren't a real requirement for use as a Jointer plane.

Question: lay a sraight edge along the sole ( with the iron retracted, but still clamped up like it is in use) Toe, mouth, and heel should be coplannar. Behind the mouth? not really needed to be. As long as the sole isn't bowed up on the ends like a banana, should be able to do it's job.

I've have a couple wood bodied jointers that had a high spot right behind the mouth...not good. A few swipes with a try plane, a check with a straightedge.....good to go.

Fingertip on oppisite corners, see IF the plane will rock, then switch cormers and try again. Plane doesn't rock? Means no twist. Finger tips on each end, try to rock the plane....no movement? sole is ready to work.

Be advised, a sole clamped by itself in a machine type grinder will flex. hard to make it flat when the sole flexes everytime the grinder wheel moves back and forth.

A jointer plane works because it is a long bodied plane. It is not a smoother. It is for making an edge straight. Allow the plane to do the job it was designed to do, and not force into something it isn't.

Is my Stanley Type 10 #6 perfectly flat along the entire length? Doubt it, but it does a very good job at what it was designed for. Like the faces of a glued up panel. Makes the panel flat as can be.

IF the OP wants to throw some cash towards Tom, hey it is his money. I'd save it for those smoother planes that would bennefit more from the grinder wheels...

[Reinis Kanders]

Thanks for the info. I have a nice No.7 that has a quite convex sole thus the question. I tried a wooden block with 80 grit to remove the belly near the mouth, but it was taking me forever. I have a lot of other planes so I put it on hold, but it is a Millers Falls plane in nice shape with great iron, but it hollows the edges if I am not careful.

[Brian Holcombe]

I shoot with a #7 pretty regularly. Not on a shooting board, but on my bench with the material held via holdfasts and jigged up 1/4"~ over the surface.

[steven c newman]

And...is that what the #7 was designed to do????

[John Densmore]

This is a plane I picked up last year. It came with a group of tools, and I'm just now getting around to fixing it up and using it. Over all is was in pretty good shape. It looks like the previous owner gave it a paint job.

It just seems that the blade would have to protrude a large distance to be able to cut.