Q about Dunbar's plane article in PWW

theory vs practice

Bill Tindal, E.TN

>Some time ago I had the sole of a #5 surface ground to correct the problems I created trying to do it myself. (Paying to surface grind a sole is very good value. While some of you may be able to do it yourself I'll bet that most won't). The bladeless plane was simply clamped in a vice , the ends supported by jack screws and they ground away. It came out flat to less than0.001".

From this experience I conclude that this #5 Bailey was stiff enough that installation of the blade did not affect the sole flatness. I consulted with Stephen Thomas on this project and he was not surprised that it was irrelevant whether the blade was installed or not in a Bailey frame.

Also remember

Wiley Horne--So. Cal.

>that in a Bailey or a Bedrock type, that the blade, cap iron, moveable frog part,and lever, are a single unit. Those parts are like a sandwich, screwed into (Bailey) or perched (Bedrock) on top of the sole. In other words, tightening the lever screw is not tensioning anything other than the blade/capiron/moveablefrog/lever sandwich. There is no tensioning of the sidewalls or sole.

Now in a wooden plane, or an infill, it would still be good practice to condition the sole with the blade at operating tension.

Wiley

Country boy test

jim reed @ tallahassee

>I clean new (to me) planes and give them a bench test. If it does not rock and I cannot see daylight, it passes #1. After sharpening, I do a cut test on scrap construction lumber. If it pulls a long thin shaving on about pass three, it passes #2. Stanley Bailey planes that have not been abused (heavy rust, drops) have pretty flat soles in my experience. In my opinion, extreme flatness is for metalworking, not woodworking.

Re: Also remember

ThomD

>"In other words, tightening the lever screw is not tensioning anything other than the blade/capiron/moveablefrog/lever sandwich. There is no tensioning of the sidewalls or sole."

That's an important distinction.

I deal with accurate machines from time to time and I would wonder whether it's the whole issue. Absolutely true you won't get that wedging effect you get with... a wedge. But stuff does get loaded up and if every single part isn't bearing evenly, or isn't sufficiently beefy for the job, you probably wiil get a hollow or bend somewhere, it may not be symetrical. I'm not saying it's measureable, I haven't measured it. But if it's the case that the most accurate rifles made on very high tech machines, still need to be completelly disassembled and remachined to ensure absolutely square clean and evenly bearing surfaces, then I find it hard to believe we aren't getting some heave ho out of planes, not made of 4140 but sewer pipe iron. It's the kind of issue that would explain why it's taken a while for the Stanley type of plane to catch up. It's the kind of thing I guess LV knows about, since they are setting up to machine most contact surfaces.

Re: Country boy test

Mark Harrison - Brisbane, Australia

>I would agree with you up to a point. The critical parts are around the mouth, particularly forward of the mouth. If the mouth parts are hollowed relative to the rest of the sole, you get all sorts of 'orneriness. Dipping, catching and general gouging of the work.

I bought an almost unused wooden coffin smoother a while back and I couldn't get this blasted thing to take a shaving worth a damn. I put a straight edge (not a machinist's straight edge) and found the mouth was hollow. I flattened the plane using a jointer plane and it behaves completely differently. I still haven't got it to perform to my complete satisfaction (moving from Sydney to Brisbane has interrupted my woodworking) but it is a whole lot better than when I got it.

Actually when you look how Japanese craftsmen tune their planes, you realise that the whole flat plane fetish can go too far.

Anyway, I know that none of my observations are original but certain truths need to be repeated at least once per generation :-)