flat soles and straight edges. An Experiment

Re: Very interesting

Sgian Dubh


>I guess there could be Barb, but I suspect others have had a go at it already-- I'm thinking of the sole bending and testing element.

I took a look at the link Bugbear (Paul?) provided to the 1996 online discussion. The thread left me as cold as chilled porridge. Far too nit-picky and the going backwards and forwards over what seems to me to be unimportant and esoteric minutia.

I'm just a plane user. As long as I can get them to do what I want that's good enough for me. I don't know if I'd be very keen to analyse every last ounce of enjoyment out of something that's essentially a skill that develops with practice. I demonstrate basic planing techniques often enough to learners. That's easy enough to do, but I think it would be very hard to get over in written words what can be shown one-on-one or to a smallish group in just a few minutes. Slainte.

Re: mechanical analysis from 1996

Greg Sloop, Portland Oregon


>In my experience, with no scientific approach or measurements, I *DO* believe that the planes will deflect or bend significantly.

I find that a tight mouth doesn't reduce tear-out, at least not by holding the fibers down. What it DOES do is reduce the tendency for the plane to "dive" when the iron digs in.

I can see this clearly when taking a fine shaving on tough to plane woods. If you apply substantial downward force during a pass, the plane will grab and dive.

If the mouth is wide/open, it will dive a LOT more and cause more tear-out.

If the mouth is very small this dive is very much minimized.

Now, very careful application of the down-force will allow both to work equally well and neither will produce tear-out, but that's often easy to screw up and forget on a single pass. A lot of induced tear-out will be the result.

(In my observations, if one uses a wide mouth, and applies down-force right near the center, just enough to hold the plane down firmly, and pushes at the base of the tote, mainly forward, this dive disappears. With a very small mouth, it�s almost impossible to get the plane to dive, even with very serious force on the tote and front knob.)

It's always been my belief that the plane flex was a cause of this, but I have no basis in measurement for believing it - simply from my observations on many different cutting angles on numerous planes.

Both the LV and LN BU jacks have this tendency.

An alternative argument might be, that somehow this impacts blade projection, but I discount that as the case since mouth size appears to cause it to be vastly minimized.

Anyway, I would guess this "flex" could be quite easily, say 5-10 thousandths of an inch, depending on how much force etc. It's substantial, lets just say that - I don't want to give the impression of precision and accuracy in measuring how much deflection is occurring. It's just a WAG, somewhat tempered by first hand observation.

This may be why some believe a �very tight mouth reduces tear-out.� It does, but only, IMO because it mainly reduces the impact of plane flex. (The mechanics of cutting angle vs. cutting the fibers is unchanged, but additional factors that impact overall performance come into play too. [(i.e. more difficult woods do require higher cutting angles for optimal performance, but the narrow physics of the optimal cutting angle isn�t the *only* factor in overall performance � though I think it�s the largest factor.)]

Cheers,

Greg

OK but...

Frank D. in Montreal


>I fond this discussion very interseting, and tend to share the POV that a sole can flex, but, as well as Thom's consideration above, I've come to wonder how the sole of a plane can flex unless the wood underneath it flexes the same amount. If the piece of wood is lying flat on a bench, then that means the wood would have to compress as much as the plane's sole flexes...highly unlikely it seems to me at first thought.

Re: OK but...

Greg Sloop, Portland Oregon


>Why would the wood need to flex? (I'm not sure what post of Thom's you're referring to, and perhaps if I did I might be more enlightened.)

In short, what appears to happen is the wood stays flat. The plane flexes _upward_ at either end (or perhaps only one end - I suspect more force comes from the tote) and the result is the blade sticks farther out/down in relation to the heel and toe of the plane.

Deflection of the wood is of no real consequence, IMO.

However, what I've seen wouldn't have much impact over a long board - say four feet or something - thus not impacting jointing much... But my strong opinion is that it is quite possible to flex the sole of a jack style plane - even a LV or LN - more than a trivial amount.

This doesn't appear to occur nearly as much in the BU smoother, but I have less experience handling this in many dozens of configurations, so it may or may not occur. (i.e. My lack of seeing it doesn't mean it doesn't occur, just that it hasn't been observed. But, IMO, my observations have much lower statistical power for that plane vs. BU Jacks and these kinds of observations, and thus may not have adequte numbers to show a "positive" result.)

Cheers,

Greg

Re: conceptual problem

Greg Sloop, Portland Oregon


>I'd agree that examining a plane in terms of general use, this highly technical, analytical approach often doesn't give much benefit to the user.

However, in trying to examine the factors that go into overall performance may be useful. In short: If you're trying to change something to get a better performance, knowing which factor has the _most_ impact on a particular set of outcomes is really important. If you're fiddling with a very unimportant factor in trying to get better performance for a very particular set of circumstances, then you'll be very frustrated.

As I've said before, at least in the tech world, flipping the right switch is the easy part. Knowing which switch to flip is the hard (and expensive) one. (Most experts really earn their money by saving tons of time by NOT fiddling with unlikely or unimportant factors as they relate to the desired outcome. Narrowing the scope of problems to be examined is vastly important! Many experts are, contrary to what they'd like to tell people, fixing things by trial and error. The difference betwixt the expert and the hack is that the expert only has perhaps a few trials to make, where the hack has millions.)

Also, for those looking to change design - such as LV/LN et al. - this kind of work is, IMO, exceedingly valuable. Again it's knowing what factors impact which outcome and by how much. Otherwise you're fiddling around in the dark just flipping knobs and dials and hoping that something goes right...not a very enviable place to be for success...

I am beginning to say regularly, but still rarely follow through... "Measure, document and track everything. Eventually you'll often notice something that is important, and the result can be really incredible." (Applies to nearly everything...)

Cheers,

Greg

Re: OK but...

Sgian Dubh


>You're all missing the point that I twist the wrists together towards either the top or the bottom when holding the plane handle and knob depending on what bend I want to put in it.

Have a wee re-read of the description of my experiment somewhere further up this thread. The shape of the wood is irrelevant as far as I can make out when it comes to me bending a plane sole on purpose in use. Slainte.

ah so! Got it...thanks

Frank D. in Montreal

Re: conceptual problem

thomd [email protected]


>Both the analytical and the one mind are valuable stances.

If you want to make a point that flexing is doing something, it would be worth knowing:

A) whether flexing occurs

B) whether there is a conceptual framework where it could do what is claimed for it.

On the other hand, performing a task comes from mastering all the sub routines to the point where the individual actions are executed with as few thoughts in mind as possible.

It may be true that the half dozen people on earth who actually engineer new plane designs need an analytical approach, though most of the money is in selling these planes to people unlikely to be able to tell the performance difference. Which is why the plane business looks as it does, and the bicycle business looks quite different.

Re: OK but...

thomd [email protected]


>Man I have enough trouble keeping the handles attached to metal planes as is, I really doubt there is any flexing of the type you are describing happening with most planes, and I wouldn't in any way want to do that as part of my planing routine. The biomechanics of making like Charles Atlas with one of those bending bards, while shooting an edge, don't appeal to me. I'm not even sure I want to measure that for fear of breaking the tote. It took a lot of force to deflect the plane I measured. And doing it via the handles would require a lot more effort. I should measure my Record 7 just in case the LV BU is particularly stiff and that is throwing the whole thing off. So stay tuned, I may be back with a red expression on my face.

I would agree, though, if you can curl the plane bottom without reference to the wood surface, then you could affect your cut, and my earlier objections would fall away (well not the one about how difficult it is to do this). There is however a further problem. My claim has always been that the reason we have longer planes like jointers is in order to limit the amount of inbuilt hollowing ability they have, and allow reasonable amounts of joint spring. DC has made a similar claim relative tot he size of work he does by noting the relationship of plane length to workpiece length as being 1-1. The last thing these planes need is "shorter" bases In fact if anything more concave (profile) would be more useful than convex. If one wants more inbuilt curve, one can simply switch to shorter planes. If one wants infinitely variable curvature for jointing or straightening boards it would seem to be like working with a drawknife; not a bad thing, but a thing for which there is already a tool.

Re: What a load of BS

thomd [email protected]


>OK, back to the bad science.

I happened to walk through the shop and the LV BU jointer was still there in the fixture. I tweaked the front and back handles and easily got 5 thou deflection at the mouth. So much for what I think...

It took moderate force, not as bad as I thought, though still some strain on the handles and the neutral feel I want in the hands.

I still think it would be a bad practice as far as trying to "shoot straight". And I don't see the point in making "shorter planes". But I'm happy to leave that up to the individual.

Re: OK but...

Sgian Dubh


>thom, it takes very little to flex a Bailey No. 7 plane sole. Just twist the wrists towards each other a bit. There's no need for bulging kneck veins and sweat on the brow.

I'm not a big powerful guy. But I discoverd the other day how much flex I can get with quite small effort. I'm not sure I'm able to define the muscle groups used in the exercise but most of the effort seems to come from the shoulders and upper arms using the lower arms and wrists as levers to transmit the force. Maybe I'm stronger than I think? After all, even at my advanced age of over 50 I still enjoy going out and playing rugby which involves gratuitous violence and the cracking of opposition skulls. (Maybe I still play rugby because it's the best excuse there is for getting out of the 'Saturday shopping with the nagging queen hell' and, instead, drinking too much beer in jovial company, ha, ha?)

I can't ever recall a handle or a front knob ripping out. That's not something I've ever been concerned with. Slainte.

Re: What a load of BS

Greg Sloop, Portland OR


>I'm not advocating "using" this flex, just that it exists.

And yes, it seems worse on my Stanley #7C. Not that it's got a lot of use, but just my general feeling - though the thin iron etc probably makes it more pronounced and more difficult to isolate it to just flex of the sole.

It's probably not of a lot of use in "solving" a problem really and especially the jointing one, but something to consider in the grand scheme of things.

I find it most noticable when taking very thin shavings on very tough wood, with the mouth quite open, esp. when using cut angles that are too low, IMO. In those cases, it's very, very easy for the plane to jump in and take too aggressive a cut and produce a wide swath of tear-out.

Just musing...

Cheers,

Greg

Re: conceptual problem

Greg Sloop, Portland OR


>You think most of the blokes on bikes CAN tell a difference? Man, I must be out of touch. I suspected most of the tri-spoke carbon wheels and areo bars, I see, were for looks! :)

'Cause I assumed for most it wasn't how well you rode it was how cool you looked.

(IMO, look on the hills. It makes the cool looking dudes stand for what they are - at least mostly - posers. The guy on the 15 year old bike dropping them left and right and riding on a pillar of fire over the summit is the real man. :) )

Just giving you stick... :)

Cheers,

Greg

Technique and Real Life Planing

Dan Clermont in Burnaby


>I am glad Sgian and ThomD have taken the time to create jigs and fixtures to test the flex in a plane sole along with how a sole can be manipulated by the flip of the wrist and I understand Sgian uses this technique for spring jointing.

However, their have been several times I have wanted to remove tearout from the center of a board (40" long) but not from the ends yet I cannot seem to remove that tearout without planing the ends of the board down to be within the same "plane" as the the existing tearout. Yes, I am supporting the board throughout the length and it sits flat on my bench which is 3" thick and pretty flat from my measurements.

What gives?

TOnight, if I have the time I will try the spring jointing experiment with my LN 8. First I will joint an edge my usual way and get a full length shaving. Then I will try twisitng my wrists and see what happens.

Stand By

Dan Clermont

I will have to try this sometime but I think if one has a "perfectly flat" board on a "perfectly flat" bench flipping the wrists will not allow me to remove 5 thou or so from the center of that board. Then yet again, I will have to find some time to try this.

Re: Technique and Real Life Planing

Greg Sloop, Portland OR


>It may not allow you to remove tear-out, but I believe it can allow you to remove "extra" (depth) of material in the center.

IMO, it's not likely to be very controlled, thus not very able to remove tear-out. (At least that is my experience.) But I certainly believe I can get it to dig in and remove extra material.

Cheers,

Greg

I suppose if you could get it to do this in a controlled and consistant fashion, then perhaps it could help with a sprung joint. I certainly don't believe I could do it, but perhaps others could.

Re: what's .005?

thomd [email protected]


>On a CAD basis it seems as though a .005" projection plane would give you a gap on a 6' board of about .1". If you flex in another 5 thou your gap would appear to be .2" which is a lot. Those numbers don't seem that far off my experience either.

Re: Technique and Real Life Planing

Joel


>To remove tearout in the center of a board just use a shorter plane. That's what smoothers are for. Or is a scraper.

Bending a plane seems to me to be the hard way.

Re: Technique and Real Life Planing

Dan Clermont in Burnaby


>You are right Joel

I wasn't talking about using a Panel plane or a jointer. I was using my 604 and or 604.5 to remove this tearout.

Haven't tried the experiment yet tonight. Been busy playing football with my 2 year old (what an arm!) and kicking the soccer ball with my daughter

Later though

Dan Clermont

Re: Technique and Real Life Planing

Joel


>Actually there's a fairly big difference in size between a 604 and 604-1/2

THe former is a fairly large smoother, the latter to big to be a convient smoother (althought the size seems popular these days for reasons that escape me).

But even the 604 has a pretty large footprint for a smoother - when I have a problem like you describe I use an infill with a 7 1/2" footprint or an even smaller wooden plane.

Re: conceptual problem

thomd [email protected]


>Well go back thirty years no mountain bikes. Aero stuff could go oodles futher if it wasn't perceived as harming the sport. Click on binding; several material revolutions like if you opened the LV catalogue and saw the latest planes were made of carbon not sewer pipe. Cold foged aluminum, surplants stamped steel, now CNC. 10 speeds have 20 speeds; clinchers not sew ups; disc brakes; recumbents. Rapid fir index shifting. LED lights. I can certainly tell the difference with a lot of this stuff and I think anyone can. Like the replacement of steel rims with alloy across the whole range of bikes means one can stop in the rain. I agree there are just as many posers, probably, but as far as technology that actually helps, bikes have really moved.

Re: Technique and Real Life Planing

Pam Niedermayer - Austin, TX


>Yep. Besides, it would have to be a big hunk of tearout to worry about it in a joint. I know, it's not ideal; but I put these things in perspective.

Pam

Re: OK but...

Dan Clermont in Burnaby


>Hi Sgian,

I tried your claimed twist your wrist to manipulate the plane sole.

First I tried a Bedrock 604 with a nice sharp blade. My standard planing technique produced a 5/10000 whispy shaving on some figured easter maple (slightly figured). Twisting the wrist made no difference from what I could tell.

Next I tried my LN 8 thinking the length of the sole may make a difference. I created a hollow in the center of the board just like you would do with a spring joint. Once I created the hollow and was unable to get a shaving I tried your wrist technique and much to my amazement I was able to pull a small shaving (about a thou).

I suspect the Bedrock 604 sole was so short and the shaving so thin it made no difference whereas the length of the 8 allowed more deflection even though it was slight.

Must admit, I wasn't comfortable twisting the wrists and don't think I personally could spring joint a board cause I use my left hand as a fence.

Thanks for your efforts in testing this.

Dan Clermont

Re: OK but...

Sgian Dubh


>Dan, the point is that now you know this sole bending thing is do-able. I've claimed to do it for probably a couple of decades now, and, more recently, having found myself in a teaching role on a regular basis I've been demonstrating it to learners. It's only in the last year or two that I've made mention of employing the bendability of long plane soles in my work in forums.

I can't say if you'll be able to use the ability to bend plane soles to advantage. It may just be an interesting piece of information. I believe I use the knowledge to advantage, but that's just me.

Hand plane use is a very individual thing. What works for me may not be comfortable to you. I often think it's all too easy to get hung up on the mechanics of a job rather than just get on with it. Plane sole flatness I suspect is less of an issue than people make of it.

Another point. Who says, for example that a plane sole has to be flattened and then taken through all the grits to a mirror bright 8,000 grit, or whateever? To me, that's probably the oddest thing I've ever heard. If a plane sole is flattened to only 40 grit or perhaps 80 grit it'll still work perfectly well. Probably it works better even than something that's taken down to 1000 grit. There's a lot less friction to deal with for one, and it usually only takes ten or twenty minutes to achieve in the first place.

If anyone spends more than half an hour flattening a plane sole, then, from my own money making business driven perspective, they're spending far too long on the job. On the other hand, for some people, woodworking, tool collecting, and things like plane tuning and saw resusication(sp?) is a suitable end in itself. Neither end of the spectrum is right or wrong-- they're just parts of the spectrum. Slainte.

Re: OK but...

Dan Clermont in Burnaby


>Hi Sgian

During my teting the sole unsupoorted so the board was hollowed. DOn't know how much flex I would have gotten with the thick sole on a LN 8. Probably would get more flex on a Bailey/Bedrock cause of the thinner casting. I take your word and believe you when you ran your tests with the flatness plate and a Bailey #7.

With the moveable toe plates on the Bevel Down planes I would think twisting the wrists may cause the toe pieces to move. At least it would if I did this with my LN 62 and from what I recall with me tests the LV has a similar adjusting mechanism for the toe piece

Once again, thanks for testing this theory. It was a good experiment

Cheers

Dan Clermont

Re: OK but...

Sgian Dubh


>Don't forget though Dan that my testing wasn't particularly scientific. There were no controls to eliminate error and the like. What little testing I did was done rather crudely, and measurements were a bit rough and ready. On the other hand, as I've said before, I think I tend to use planes quite intuitively-- I don't get too excited about the 'proper' method, whatever that may be.

Even my sharpening technique is probably somewhat hit and miss. No guides, no measurements, nothing fancy with grits. For me it's just a case of find a stone, or anything abrasive really that's handy, and have at it-- although I do admit to liking my ceramic stones.

I have no experience of the other plane type you mentioned. I've never used a bevel up plane apart from block planes, so I can't comment on how the soles or adjustable plates in front of the mouth might bend or twist.

In the end (I think with plane set up and usage) that whatever gets you to the desired end result is all that matters. Slainte.