On planing and convexity

This ia another reason why sharpness ...

HC Sakman


>...is so crucial, as well as perfectly tuned sole and mouth. Finely tuned plane with very sharp blade sure cuts with much less effort, thus decreasing applied downward pressure by the user. That prevents or minimizes the workpiece deflection you're talking about.

Chico...

Well, since were adding ingredients...

Gary B in Central NY


>another factor, as Don McConnell has mentioned, is that the arc (he didn't mention a straight line) that a plane can acheive is a function of the length of the plane combined with the thickness of the shaving. I bring this up because it's something I thought about for a while. consider a power jointer, it has an outfeed table set to the height of the knives so that all three surfaces register in the same plane. a handplane cannot because the back of the plane isn't adjustable. I've always wonder why someone like lee valley didn't come up with an adjustable toe configuration on longer planes so that all three surfaces could register.

Re: Well, since were adding ingredients...

Rob Lee


>Gary -

That would be a nightmare to manufacture in metal (some Japanese planes are made that way in wood)....it's hard enough to make an extended coplanar surface in metal to the tolerances that are held now - I don't want to think about two adjustable parallel surfaces held to those tolerances...

I guess it's also a question of limits - and how far you want to take the precision of tools that work a medium that isn't really capable of remaining stable within those limits...

Awareness of how tools function, is certainly important as it leads to predictable and repeatable results for a given technique. I'd submit that technique has a far greater impact on the results of more people's work than the tools do... woodworking is not machining ....

Cheers -

Rob

Please...Let me complete your last phrase.

HC Sakman


>"Woodworking is not machining METAL."

Chico...

Re: Well, since were adding ingredients...

thomd


>I'm not convinced that an out table that is set at the height of the blades is a better design. It's clearly a necessary design on a rotary cutter, that has pretty unlimited cutting geometry (eats anything that gets near it). There are things you can do with a power jointer, like plane a deep rebate, or a significant taper, either one in a single pass, that just don't figure with hand planes, but require the outfeed height to be adjustable and higher than the infeed. My power jointer has a maximum cut of 1/4", I think. I have certainly used most of it on large tenons, from time to time. The kickback danger is there on those kind of application

What the coplanar infeed outfeed tables design would offer if it could be manufactured (and if it was incredibly necessary it could be made in a fixed format, and it can be made fixed in wood in about 3 seconds) is the possibility of removing a full length shaving of a fixed thickness, like the pictures in the textbook shows happening in the power jointer example. (I have spent a certain amount of time, by the way, teaching people to straighten curved boards on the jointer is not as simple as pushing the board through.)

Such a coplanar hand plane would probably be worse at straightening because it would be less adept at the curved work you mention. When I make a board four square I flatten two sides in relation to each other then scribe, waste, and flatten the remaining side. I don't do a lot of full length shavings. And anyway I can do those fine with the planes we have.

So I'm not sure what such a design would offer. But it would be easy to find out in wood. It might well do something interesting or unexpected. I think I will try it. We probably need a technical forum, because I don't think this is the right place for this kind of stuff, and I know the UK workshop forum isn't either.

I agree

Gary B in Central NY


>that it would be very difficult to manufacture, and is not necessary. but I do find it interesting. it's my theory that only the front half of the plane could be registering after a shaving is being cut. But you know what theories will get you.

Gary