Flattening a convex plane bottom

[Matt Chantry]

Hello All,

I have read through the info on flattening hand planes, but I haven't been able to find any ideas re: how to deal with a convex bottom. I have a 60 1/2 block plane that I can't flatten using standard methods. It just rocks and makes the curve worse.

I'm hoping someone has a way to deal with this problem.

Thanks

Matt

[Fred Gross]

I had one like that....I placed it in a vise, started with a flat file to work out the crown and periodically checked my progress with a straight edge to make sure I wasn't going too far the other way. Once I had the crown out, I lapped the sole on various grits of aluminum oxide paper stuck to a piece of glass to remove the file marks and get the sole dead flat.

[Matt Chantry]

Fred,

Did you file perpendicular to the plane's length?

Matt

[Fred Gross]

Matt,

I did it like flattening a wide board with a handplane....sort of a 45 degree across the long axis of the sole and alternating sides every few strokes (I gueses you could think of it as a "X" pattern). Hope that helps.

Fred

[Eddie Darby]

I have a 1" x 42" belt sander, so I would go at the bottom with the plane on it's side, to create a flat middle section. I would use an old and less aggressive belt.

After enough flat has been created, I would then go with the flat plate approach. Stay away from the mouth of the plane, and the ends, with the belt sander, since you do not want these areas to be concave. Leave these areas for the flat plate approach.

All you need is enough flat on the sole to go with your initial approach.