How to lap the sole of a large plane?

[Bob Jones]

I recently acquired a Millers Falls No 22 (like a Stanley 7) from my Grandfather-in-law and I am refinishing it. I have read Garret Hack's book and read alot on this website. The one thing i can not figure out is how to flatten this 22" long sole... Do I need a 4 ft long piece of glass and several sheets of sandpaper glued end-to-end?

I am in the porcess of buying some more old planes from ebay, so I was just going to re-hab all at once (as time permits). I would rather not buy online, but I can not find a good source for old planes in the Memphis area. Antique shops are no good and I don't have years of patience to check garage and estate sales....
Thanks for the help.

[Brad Olson]

Unless you kow the sole is out of flat or in really bad shape, there really shouldn't be a reason to lap it. In fact, I wouls suggest attending to other refurbishment items first and then seeing if you need to lap the sole.

If you do need to lap the sole, I have used a 3" wide piece of AlOx sandpaper that was from a belt sander. You can either glue this to a piece of MDF or glass. 220 grit is good for most lapping tasks. If you are going for a show piece you can go higher in grit, but isn't neccessary and difficult to find paper in this size above 320 grit. Klingspor would be a good source for oversized sandpaper.

[Clinton Findlay]

http://www.cianperez.com/Wood/WoodDocs/Wood_How_To/INDEX_How_To.htm

If the Hack book doesn't cover enough detail, I'm sure the above will have it for you.

My shed is packed up, in order to allow machines to get access to the rear of my house, through the shed. Therefor, I can't use my bench at the moment. I fettled a plane the other day and used the dining table, which is flat. If it wasn't flat I'd have put a piece of MDF board on the table.

I have granite pieces, ranging from a 14" square to a 6" wide piece 5" long. Usually I use them.
I prefer them as I bought them for the same price of float glass, from a demolition yard. I'm Australian, so I'm not sure what you call these places over your way???
I was originally looking for some more glass, when I found the granite. I don't like using glass as I worry that I will drop it. The granite is dead flat from the polishing process. Scout around and see if you can find the granite as you look for float glass from your building demolition 'resellers'. Do you call them 'junk yards'?

I start and work on 80 grit, and when flat I use 120 grit to finish. Some go higher for a nice look.

I can buy sandpaper by the length (removed from rolls) in my local hardware store. The rolls are usually 50 meters in length, I buy it in 4 or 5 meter lengths as I need. My local has 4 and 6" widths in most grits, up to 2000 grit. I'm sure you can find the same in your country, if you have trouble, look in a small, local, paint store.

I'll post a pic of the set up I used on the table.

[Tyler Howell]

In class our neander instructor used PSA sandpaper on a DJ20 jointer to lap planes. Worked great.
I used a tempered glass door from an old EC .

[Ben Rafael]

You can use the cast iron surface on a TS or jointer to do it. Just make sure that those surfaces are flat.
But, I agree with Brad, tune up everything else first and see how the plane works after that, it might not need the sole flattened. Unless you are going to use that plane for smoothing, it probably wont need the sole flattened.

[JayStPeter]

I went to a glass supplier and asked for some scrap, they gave me a 12"x42" piece. McFeelys sells rolled PSA paper. I buy it in 220 grit and have used that to flatten a couple of soles. You have to be careful while flattening. My experience is if you grab the handles and do like you're planing you'll do the opposite of flattening. I put the glass on the floor and kneel over the plane grabbing it from above. I prefer smaller quick movements to large sweeping movements. I only use about 6" longer than the plane sole at a time.

[Tom Saurer]

I flatten my #8 on my tablesaw top using sheets 8.5 by 11 sandpaper taped together. Worked fine and I didn't have to go out and buy something specifically for the task.

[Bob Jones]

Thanks for the advice, I'm glad to have a souce of help!

[Ben Grunow]

most tile suppliers have stock polished marble saddles in 30-36" lengths for not too much $. Might work and not too much space taken.

[Gary Curtis]

I made the sad mistake of flattening 8 or 9 planes at a time. After wholly exhausting myself, and burning through $35 in sandpaper, I started asking here on this forum.

Folks told me not to bother with my No. 6, No. 7 and No. 8 planes. Apparently jointing planes are so long, sole flatness doesn't affect the job they do. My No. 3,4, 4 1/2 and 5 were so far out of being flat it was beyond anything short of a belt sander. I asked my neighbor, a machinist, and for $50, he subjected my planes to a precision surface grinder. His company manufactures MRI scanners, if you can believe that. He brought the soles to within .0005" of true.

If a sole is only .002" out, try the hand method. More than, use the Conan the Barbarian strategy.

Gary Curtis