OldTools Archive
Recent | Bios | FAQ |
94384 | Kenneth Stagg <kstagg@h... | 2001‑06‑22 | Re: scrub planes - blade radius |
paul womack wrote: > > r = 2.5" > > So that's the radius Stanley ground a #40 1/2 scrub blade to. > Wether it's the best radius is another question Good question. What are the factors that would determine the optimal radius for a scrub blade? Off the top of my head I get: How strong is the person using the plane? What type of wood is it being used on? How wide is the blade (a given for each plane but which plane will you use?) It seems that the tradeoff (assuming that you are trying to remove as much material as possible for the least expenditure of energy) is between shortening the "shear" line of the shaving (where the fibers need to be seperated from one another) and the ability of the chip to bend as it passes through the mouth of the plane. Reducing the radius toward the minimum (1/2 of the width of the blade) allows you to remove a greater volume of material for a given shear line (right?) but leaves you with a thicker/stiffer chip. Of course reducing the radius may also limit the utility of the blade as it reduces the amount of material that you can remove per pass if you are not using the maximum depth that you can handle. -Ken |
|||
94386 | Steve Knight <stevek@k... | 2001‑06‑22 | Re: scrub planes - blade radius |
here is where I have settled http://members.home.net/steve19910/web_temp_pics/scrubplaneiron.jpg Knight-Toolworks & Custom Planes Custom made wooden planes at reasonable prices See http://www.knight-toolworks.com For prices and ordering instructions. To subscribe to my good deals/beta testing/seconds email list send a email to gooddeal-request@k... Subject: subscribe |
|||
94388 | jimbono@w... (Jim Thompson) | 2001‑06‑22 | Re: scrub planes - blade radius |
BugBear calculated the correct ( or original ) radius of a scrub plane blade to be 2 1/2 inches. Thank you, thank you, sir! I have been wanting that piece of information ever since I started using the scrub plane I got from Steve Knight. The plane cuts as well as you could ask for, but I have always thought that the radius was too tight. I just went out and checked it. It is ground to a one inch radius. I did not change the radius because I did not know what to change it to. Now that I know, I will regrind it. Thanks again for a good piece of galoot detective work. Jim Thompson |
|||
94390 | Steve Knight <stevek@k... | 2001‑06‑22 | Re: scrub planes - blade radius |
On Fri, 22 Jun 2001 10:49:36 -0700 (PDT), you wrote: >The plane cuts as well as you could ask for, but I have always thought >that the radius was too tight. I just went out and checked it. It is >ground to a one inch radius. > > I did not change the radius because I did not know what to change it >to. Now that I know, I will regrind it. > >Thanks again for a good piece of galoot detective work. > but remember without a tote you might not have the leverage to make it work as well. I started wit ha less curved iron on the first ones. everyone said add more curve (G) Knight-Toolworks & Custom Planes Custom made wooden planes at reasonable prices See http://www.knight-toolworks.com For prices and ordering instructions. To subscribe to my good deals/beta testing/seconds email list send a email to gooddeal-request@k... Subject: subscribe |
|||
94392 | "Croxton Gordon" <lawyer@e... | 2001‑06‑22 | RE: scrub planes - blade radius |
> BugBear calculated the correct ( or original ) radius of a scrub plane > blade to be 2 1/2 inches. > It seems to me that the optimum curve would have an exposed depth equal to your depth of cut (thickness of shaving), which would depend on the wood species, grain nastiness, and your strength. The other dimension would be the width of the exposed iron (a chord?) which should be a bit less than the blade width on each side, so that the shaving tapers on the edges to nothing and you don't get tearout at the edges. I've found myself wanting a shallower radius than the previous owners of scrub planes. Cheers, Croxton, enjoying the heck out of his new/old 40-1/2. |
|||
94397 | "Shannon Salb" <ssalb@l... | 2001‑06‑22 | Re: scrub planes - blade radius |
> It seems to me that the optimum curve would have an exposed depth equal to > your depth of cut (thickness of shaving), which would depend on the wood > species, grain nastiness, and your strength. Hmm, I don't think so. The depth can be varied by raising and lowering the blade (like all planes). The aggressiveness can also be varied by the amount of skew that you hold the plane relative to your plane's direction. Sure, the amount of curve affects the function of the plane (and I'm no plane scientist). Too sharp and the plane is acting more like a gouge and it will balk more than it needs to when the iron is not razor-sharp. But too shallow and you lose some of the effectiveness. But I don't think you'd want to change the curve depending on your wood, because 99% of the bang could be gotten out of changing the height of the blade or the skew of the cut. (Well, anyway, these are my speculation.) -Shannon |
|||
94412 | jimbono@w... (Jim Thompson) | 2001‑06‑22 | Re: scrub planes - blade radius |
You put a tote on mine. What I object to with the smaller radius is the deep grooves that I have to take down after scrubbing. I dont mind taking a shallower cut with a greater radius. Of course, I am saying this without having actually used a larger radius. I may be back here later saying it is a mistake. But I gotta try it! Jim Thompson |
|||
94380 | paul womack <pwomack@e... | 2001‑06‑22 | scrub planes - blade radius |
Having dipped out on a scrub today, I've been consoling myself with some scrub-related net-surfing. One of the great mysteries seems to be the radius of the blade. So, maths and web time: Obviously, we start we a NOS reference: http://www.mjdtools.com/tools/list_071/20144.htm (thank you Mr. Donnelly) Now we need to calibrate: the page says the blade is 6 inches long, and since we know the blade is for a #40 1/2, (for cryin' out loud Jeff, it's a scrub plane, what were you expecting?!) http://www.supertool.com/StanleyBG/stan5.htm#num40.5 we know that the blade a 1 1/2 inches wide. Pixel counting time. left most pixel 14, rightmost 96, so 82 pixels are 1 1/2 inches, 54.6 pixels to the inch. top pixel is 6, bottom is 334, so 328 pixels are 6 inches, 54.6 pixels to the inch. They match, which makes me happy. corner of blade is 326 pixels, so the "curve" is 334 - 328 = 6 pixels deep, which is .11" (7/64") The radius of this can be calculated: http://www.egroups.com/message/oldtools/58360?source=1 r = h/2 + (l^2)/8h r = .11 / 2 + (1.5^2)/(8 * .11) r = .055 + 2.25/( .88) r = 2.5" So that's the radius Stanley ground a #40 1/2 scrub blade to. Wether it's the best radius is another question BugBear |
|||
94382 | "Nuno Souto" <nsouto@n... | 2001‑06‑23 | Re: scrub planes - blade radius |
----- Original Message ----- From: "paul womack" |
|||
94553 | Larry Poffenberger <lkp@r... | 2001‑06‑26 | Re: scrub planes - blade radius |
At 01:46 PM 6/26/01 +0000, Jaime Metcher wrote: >snippage here >If the grain is at all cranky, the standard radius (2.5") gives you a >choice between backing out the blade and taking a million tiny passes, or >getting tearout that looks like the aftermath of an artillery >bombardment. I keep meaning to regrind mine - in the meantime I use it >only on well-behaved wood. > >Jaime Metcher Hi Y'all, As I've mentioned before, I often use a #3 with a Scary Sharp (tm) blade with a crown (gently curved) for hogging off or preliminary smoothing of burled walnut. It works well with the plane in a 45 degree, gross grain attitude. With attention to grain and a sharp enough blade, I can avoid tearout, a real problem with burled walnut. I think the reason you don't see any modern furniture with figured walnut is there isn't anyway to work it except with hand tools. It's a real shame most people have no idea how extraordinarily beautiful wood furniture can be. Regards, Larry Larry Poffenberger lkp@r... OR rustytool@r... For sale and information at: www.rosewoodandbrass.com |
|||
94556 | paul womack <pwomack@e... | 2001‑06‑26 | Re: scrub planes - blade radius |
Larry Poffenberger wrote: > I think the reason you don't see any modern furniture with figured walnut > is there isn't anyway to work it except with hand tools. It's a real shame > most people have no idea how extraordinarily beautiful wood furniture can be. At the risk of driftin gently OT, you underestimate the "more power" tendancies of those people. There's no wood so gnarly it can't be sawn near to size, and thickness sanded < |
|||
94547 | Jaime Metcher <jmetcher@m... | 2001‑06‑26 | Re: scrub planes - blade radius |
>From: "paul womack" |
|||
Recent | Bios | FAQ |