Here’s some sketches of a modified Norris-style adjuster (either banjo or pin) that should be easy to make with simple tools. I haven’t tried yet, but have the materials and will do some experimenting over the next week or so.
One design weakness might need thinking about – when extended, the banjo/pin will be leveraged by a relatively short length of threaded rod!
The goal is to design an adjuster that can be fabricated in most shops, functions well, and is scaleable for both full-size planes and smaller block and mitre planes.
Malcolm
Edited 4/16/2006 6:35 pm ET by Malcolm2
Replies
I had a thought a few years ago that I put in the memory banks of my mind, (yes I know, a dark and seldom used space) for a plane adjuster. Since your playing a lot with that sort of thing at the moment I'll bounce it off you to see what you think.
Micrometers have very fine threads that are adjustable for wear. (40 tpi for imperial mics). So I think that it may be possible to modify one to serve as an adjuster for a plane. They even have graduations to boot! If the frame were cut to remove the "C" the remaining piece could be the basis for an adjuster. An old one could be used but there are a lot of the Chinese made ones available ($10 to $15 Canadian here) that they could serve as cheap parts.
I know they are never going to be regarded as something for a high end tool, but should be fine for a user. Well maybe if it was a new Mitutoyo digital one.....no the mechanical first to prove the concept out.
Hey! That might be a brill idea! They are cheap, and very nicely made. I've got one ... I can feel a '1mm cut-off wheel' session with my angle grinder coming on.
Malcolmhttp://www.macpherson.co.nz
"Do I get one of your planes for free if it works?" He asked with a big grin on his face.
Develop a design that beats the standard Norris style adjuster, make me 10, and it's a deal!
Malcolm
Edit - without destroying one, hard to tell how adaptable a micrometer screw would be. The form factor may be problematic too - long and bulky. But I do like the idea of being able to dial-in shaving thickness!
http://www.macpherson.co.nz
Edited 4/17/2006 5:07 am ET by Malcolm
"without destroying one, hard to tell how adaptable a micrometer screw would be"They actually come apart quite easily to clean, repair, adjust, and calibrate. If your mic is a basic mechanical one you can spin out the thimble assembly to look inside at the threaded bits and put it back in without affecting the settings. With everything else that's on the web there must be some diagrams / pictures of a complete breakdown if you're inclined to pursue the idea further."I do like the idea of being able to dial-in shaving thickness!"Nit picking moment.;-) The graduations won't give the true depth of cut because the movement is on an incline. So screwing in .002 would actually cut a thinner shaving. But you knew that already.;-)
Thinking about this in passing last night while casting about for more information it occurred to me that micrometer parts might be too fragile - even the conventional Norris style are subject to wear and distortion, and micrometer threads are not intended to push or pull!
M http://www.macpherson.co.nz
Not to imply that I know more than you, but remember the threads are cut in hard steel, and the "nut" is split with a second nut having a tapered thread on the outside to account for wear,(looks a bit like a router collet). The reason I put forth the idea in the first place was to stimulate some dialogue and thinking that might advance the "science", which has happened. I think the micrometer's method for accounting for thread wear, even in a modified form, might still have possibilities for controlling the backlash in a planes adjuster mechanism. (Stubborn aren't I?)
No question, you know more than me!
I do think this is an idea worth chasing down.
Do you know anyone with some engineering or fabrication insights, who might be able to point to similar applications or a parallel technology?
I'll do some more research as well.
Malcolm
Bought a couple of mircrometer heads on the Bay last night. About $US 20 for the two. Will experiment when they arrive.
Malcolmhttp://www.macpherson.co.nz
Malcolm,Can I just buy you ten adjuster sets and get a free plane? I use a brass hammer I made (about 6 oz.) and a five ounce Stanley dead blow. While I'm not real fond of the day-glow orange color of the Stanley, it's just the right size.A depth of cut indicator or micrometer type readout just really isn't practical. A plane set to take a very fine shaving in a hard dense wood won't even take a cut in a less dense wood. It'll even remove different amounts depending on if you're cutting with or against the grain on the same board. Think of all the compensating read-outs you'd need.How do you adjust the vise on you're milling machine when you're tramming it in? Do you have some adjuster to do that? It's some of the most critical and accurate hand work machinists do and, even on the most expensive milling machine they still use light taps--probably with the palm of their hand but maybe with a small mallet. Why don't you invent a tramming adjuster? Being off a thousandth isn't a big deal with a plane iron but would you want your milling machine's head or vise to be off by a thousandth?I know, you could start with a perfectly flat bench and attach a CNC stylus to the plane. The stylus could reference off the bench and vise faces, read the wood, and automatically adjust depth of cut for what's needed. How about a self-propelled plane? You wouldn't have to do anything but admire shavings and polish brass when you're done. Think of the mass you could add with motors, servos, a CPU and a DRO. I'm thinking my little hammer and mallet is looking better all the time.This post didn't start out to be so sarcastic but it sure got there, didn't it. Sorry about that, I just don't see the problem with all the designs that are out there. If you're still with me, experience tells me the biggest problem with adjusters isn't the adjuster. It's getting the proper tension on the lever cap, screw cap, wedge or what ever holds the blade in place. Once people learn the relatively light pressure required to hold the blade, issues with adjusters seem to pretty much go away. Well except for weird adjusters like the side-wheel adjuster on Stanley's early #113.
> I'm thinking my little hammer and mallet is looking better all the time <
Actually, I hate hammering planes! With a lever cap, you don't need to. My technique with my little Bristol Design BU thumb plane is to sight down the throat from the top, and judge the position of the iron by the width of the gap visible in the mouth. As said elsewhere, I can get the depth of cut right first time almost all the time. No hammering. I've never hit that plane!
My new Mack Truck design will be adjusted that was as well. It's quick, reliable, and doesn't harm the tool.
Back to adjusters. I know many practitioners say that you don't need an adjuster in an infill or wooden/wedged plane, or even that you're actually better off without one. I think it is perfectly possible to make that case, but I still like the Norris-style (and the variations, LV's pivot adjuster for example), and well set up, used properly, it is a superior way to set up a plane for fine work ... in my view.
The diversion onto micrometer-like mecahisms is interesting (I WAS just joking about dialing-in the cut), but likely to be fruitless. Simolicity is the answer, and my variation on a Norris is something I'll pursue, The machining is not that challenging.
Keep up the sceptic's role ... someone has to!
Cheers
Malcolm
> Can I just buy you ten adjuster sets and get a free plane?
If they're by Karl Holtey, the answer is yes. At the usual cost to me of a Norris-style adjuster (supplied by Classic Planes in the UK, for example, something like $NZ120) even that wouldn't be a bad deal!
Malcolm
Edited 4/18/2006 1:18 am ET by Malcolm2
Well, 2 Moore and Wright Sheffield-made micrometer mechanisms turned up today. They look promising. I am going to play around to see if I can modify one to raise and lower an HNT Gordon iron!
Malcolmhttp://www.macpherson.co.nz
Malcolm, is there anything you can do to the drawing- I can hardly see it on my screen-or should I be twiddling knobs on this computer?
For simple adjusters mine couldn't be much simpler: stem, dowel, peg, knob- thread 1/4" 28tpi, although the trick is to assemble the thing so that there is minimal backlash(if one has an allergy for backlash).Some of these finer threads are available in both taps and (adjustable) dies in left hand, so by combining suitable pairs of l/h and r/h one can get fine movements.
Personally I like to have a medium fine single thread and rely on the cap's sensitivity to tightness when adjusting the cut.Why get complicated?
> Personally I like to have a medium fine single thread and rely on the cap's sensitivity to tightness when adjusting the cut. Why get complicated? <
Exactly - simple is best, and there's no need to complicate! I will spend a little time researching fine thread tooling, but I'm guessing it will be fruitless. Leaving some pressure on the cap screw not the best idea though?
I'll email you a copy of the adjuster JPEG, if that's what you're after (from work, some time tomorrow) and happy to to the same for anyone else.
Malcolm http://www.macpherson.co.nz
Philip,If you're using a Windows machine right click on the image icon and select view in a new window. You should then see the drawing okay or you can also just click on it to enlarge it to a huge size.
Thanks Larry-don't know why I didn't do that in the first place.Philip Marcou
The idea of backlash is a little overrated to me. Sure, if you're dropping $4000 or $5000 on a plane then you really want it to be as perfect as possible and, hence, no backlash in the adjuster. But I'd have to say that a little backlash otherwise doesn't bother me at all. A LOT does, but a little doesn't.The Norris style adjuster is brilliant in its design, I feel, but it does suffer from backlash problems that annoy a lot of people. Its important to keep in mind though that, with a lot of use, virtually any system of blade adjustment is going to break down somewhat and become a bit sloppy over time. Sure, they'll be great for the first few years of heavy use, but after 100 years it might be a very different matter.Then again should makers nowadays be concerned with their planes 100 years down the track? Probably not. After all they basically have just the one customer per plane - the first one.
Handplane Central
Yes, there's backlash and backlash! With a nice clean thread, and plenty of it, a few degrees of turn between going down and coming back up is not a problem, because you can tell when the movement egages and the iron starts to move.
If it's tight, or the thread is a bit 'muddy', and you can't tell when the backlash stops and the movement begins, then backlash is a real bear!
Malcolmhttp://www.macpherson.co.nz
DANG! Can you make the Type Face a bit bigger? Hard to read here...
Hard to read everywhere Will.
Do you want me to email you a printable version? Same to anyone else. Click on the email link on my web page and send me a message!
Malcolmhttp://www.macpherson.co.nz
Malcolm.. Geee I was just 'funnin' you..What I saw here was type at about 72 Points! That is about 24.5mm or one Inch in plain English... Sorry...EDIT: Or is that 25.4mm?
Edited 4/20/2006 10:56 am by WillGeorge
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