Unicorn takes first loss- feet planed

Re: Unicorn takes first loss- feet planed

Andy in China

For bevel down planes did you consider the option of unicorning on the back instead than the bevel ?

yes, but...

David Weaver

that can be done and should work fine, but I haven't done it yet because I like the low cutting angle (because the bulk of the planing that I do is rough).

I think it may be a good option for other people, though.

I'd love to be able to see the burnishing of the surface, etc, and then superior edge life in smoothing, but it makes sense that I got the results that I did and I'll continue to "unicorn" for smoothing because it's protective of the edge.

as far as other planes, though - bevel up? it works great. really great.

For people who don't want to use a cap iron, they may find that the unicorn used somewhat sparingly on the face may make for a huge improvement in their work with smoothers.

There is one area where I tried it that I shouldn't forget - beading planes. I figured it would leave a polished front edge but take away some of the lifting of shavings in less than perfect wood and that's exactly what it did.

I don't regularly use any block planes or bevel ups, but I have a cheese iron stanley 18 that I tried it on, and it really makes that plane work far better (same issues with edge protection -without it, the blades soon take some kind of damage - the one I have is unusually soft, and for some reason, I thought a pack of vintage spare irons looked neat and bought them, too. They're all like that. super soft).

For abrasive or rough work, though, no contest, the edge protection wins both in appearance and edge durability.

(Bill and others are experimenting with buffing both sides of the iron at this point - maybe he'll make a comment. It could very well be a good thing for a plane that's used with mostly power-tool use behind it - especially for planing joints flush where there may be glue present. All of my blades take a beating planing anything flush on a cabinet, but XHP/v11's contrast between clean wood and less than perfect is really stark).

correction and elaboration of back buffing

Bill Tindall, E.Tn.

I am not experimenting with buffing both sides of a plane blade, just the back side and lightly at that, following normal sharpening. I can report it made the edge feel prickly sharp. And with the crude observational powers of a 10X lens it looked like it removed some burr that had not been removed by routine sharpening( saw what appeared to be a fragment or two of burr dangling from the edge.)

My planing needs are best described as pedestrian. As such I find it difficult to communicate with those that plane for higher purposes. David and I have been talking past one another since I first brought the issue of buffing the back up. If I push a plane, it bites into the wood, a shaving thickness goes away and no divots are torn out. I have succeeded in my planing goals. The wood in now thinner than before and the surface not worse than off my machines. Repeated as needed the piece of wood becomes level, fits a space, etc. Goal met.

I think a quick buff of the back could accomplish two things, neither of which are important to David or others planing for perfection, hence my lack of success in kindling any interest in exploring these pedestrian needs. I have found the buffer so useful for my work that it now sits on the bench as others might have their honing stone at hand. So in my situation there is no convenience barrier to using the buff. If you plane to make something fit or level a joint, read on.

First, light back buffing (0.001" +/- profile) could be a way to ensure a sharp as it can get edge with a 1-2 second operation. Think of buffing the back as a 1 second cost insurance policy to sharp. Admitting my modest goals for planing, so far I have seen no disadvantage to employ the buff the back to ensure sharp.

Second, we think this tiny profile wedges the chip in chiseling, thereby reducing the stress on the delicate tool tip. If true, this tiny profile will wedge the shaving when planing and could mitigate tear-out, with no price to pay for my needs for this benefit. Given its tiny size it would add to the cap iron effect and not detract from it. It could make setting the cap iron less critical, not an insignificant benefit for those of us that plane occasionally as a situation demands.

I hope the members of Pedestrian Planners Anonymous will explore back buffing.

I can do a duration and feel ...

David Weaver

test of this. More or less laying out the flat bevel at 32, then giving the back side only a light buff instead of removing the wire edge another way, and see how it goes.

If it makes very little difference in resistance, I'll be able to report it. If I don't feel anything signifcant, nobody will.

When I don't do these things A/B one right after another, I don't notice most of the differences I suggest, either, which is why a lot of people say they don't feel things other people do feel.

The planing resistance of V11/XHP for example - it's stark enough that I thought the variance from one blade to another was due to poor sharpening, which was really odd because all were sharpened on cast 1 micron diamonds and checked under the scope and showed not even the slightest remnant of a wire from one end to another.

But I'd never have noticed such a stark difference without alternating back and forth.

Factors PPA cares about

Bill Tindall, E.Tn.

That's Pedestrian Planers Anonymous (PPA).

1. Is Unicorning Lite on the back a quick way to reliably sharp? Improvement in speed or reliability. An insurance policy to the goal of sharp with no significant disadvantage.

2. Does Unicorn Lite on the back result in any disadvantage significant to PPA? Feel is not a concern to PPA, and anything short of a 2X difference neither is edge life.

3. Does Unicorn Lite on the back make setting the cap iron for optimum tear-out mitigation any less fiddly (more tolerance for shaving thickness and other cap iron variables?

Re: Factors PPA cares about

William Duffield

Have you ever considered unicorning the chip breaker cap iron? Some considerations: You would only want to buff the top surface, because any round over of the bottom surface might resulting in chip jamming. A smoother top surface might lead to more consistent chip production, but also might require a higher or steeper front angle for the same results. I don't remember seeing any reports of chip… cap iron wear or edge failure patterns here, probably because the edge of the ch… cap iron, if properly ground, should be completely supported by the blade, and therefore subject to minimal wear.

hate to pee on the campfire..

David Weaver

.but this is what I do to my cap irons. Just on a slightly larger scale. I've prepped them with deburring wheel and buffer for quite some time. They seem to do much better with a rounded profile where they meet the chip than they do with a flat bevel.

more secrets....

Bill Tindall, E.Tn.

So far we have learned you buff your chisels, buff the plane blades, now we learn you buff the cap iron..... what other secrets have you been keeping from us? Buffing the planed surfaces before showing them?

polishing

Warren in Lancaster, PA

On Sunday night, after giving some suggestions,

I remembered experimenting with the cap

iron angle back in the 1970's. Monday morning in the

shop I got out a magnifying glass to look at the

juncture of the two irons on my planes, but in the

meantime you solved the problem. I think my angles are

about 105 degrees [75 degrees in today's terminology] between the cutting iron and the capiron, and polishing this surface also helps.

Written in an email to Bill Tindall July 19, 2007

buffing cap irons...

David Weaver

..before I started building planes, I bought about 12 try planes, 5 jointers, and some smoothers and then a bunch of used double iron sets (so that I could sell the planes that I'd bought instead of parting them out).

It took little time to learn in testing the cap iron that I liked the rounded profile. It felt better. I could spot the people who watched the K&K people and pronounced themselves experts because they ran around telling everyone to set their cap irons at 80 degrees in a flat wall and then set it 8 thousandths from the edge. Neither of these are hard to do, but they make for a miserable working plane.

I like total angles a little less than warren (I guess I'm lazy) and when I come across a stanley cap iron that is bent more steeply than typical, I don't like the extra resistance that it presents.

Regardless of all of that - I found out what I like in the front profile of the cap (which one might do if they are thinking they'll start dimensioning all of their wood by hand - finding little things that make the work easier, putting them all together and suddenly something thats "not possible", as working entirely by hand was described as on SMC at the time, including people like bob smalser who said if anyone ever worked completely by hand, their work would screech to a near halt - anyway, getting the little details right makes the hand work pleasant and speeds it up by a factor of a zillion, and draws you to do more of it).

Once I found out what i like on the cap then I had to do it to the caps. which meant rounding over the front edge of all of them on a coarse stone, and the first few, I ran through a progression of stones.

That's a pain if you're doing five. One, maybe not so bad. I got a deburring wheel for something else at the same time and realized how well the deburring wheel and buffer worked after filing the front edge of a cap iron rounded, or stoning it, and they did something that's always trouble on mild or not fully hardened steel - they blasted the wire edge right off. The wire edge on a reprofiled cap iron is super persistent. It pretty much goes away with the buffer if the deburring wheel has refined it and it's not quite so thick.

I told someone else this a while ago, won't say who

Most of my yarns probably sound like back filling, but they are either on video or in my email history. laziness drives me to look for short cuts that are as good or nearly as good. In some cases (like buffing the cap iron front), they end up just actually being dominant (better in every way).

Re: polishing

Rafael

One of the recommendations of the chip breaker study was to set the chip breaker bevel at around 50 to 80 degrees. Polishing it with a buffer or strop seems the natural thing to do.

While we are on cap iron angles

Bill Tindall, E.Tn.

I have all the Kato and Kawia papers, as well as several from other authors, dealing with investigations of the cap iron employed on planing machines. When studying variables, cap iron angles were varied 50 degrees +/-. When cap iron angle was not a variable it was set at 50 degrees. At least for the planing machine it seems fair to say that 50 degrees was found to be optimum.

Re: polishing

Warren in Lancaster, PA

I have been polishing the cap irons since 1976. In 1977 I had some troublesome wood and found that a rounded cap iron meeting the cutting iron at 75-80 degrees was very helpful; it just really shut down the tear out problems.

reasonable, and...

David Weaver

..at the time I was just picking up what's what with the cap, I was also trying to understand how double iron wooden planes fed.

It seemed reasonable to both get the shaving to slide over the cap iron smoothly, but also to get uniform feeding so that it didn't aid clogging. The height/shoulder on the cap iron above where the shaving actually touches has much more influence on encouraging clogging, though.

cap iron polishing

Bill Tindall, E.Tn.

Without friction the cap iron would not work. Seems that reducing friction by polishing is going the wrong direction. Of course in use the wood is going to leave what ever finish wood leaves by sliding on steel.

friction may not be the right term...

David Weaver

..inconsistent grabbing is more like what I was thinking, or hoping for sliding friction and getting something to be braked to a halt where that's undesirable.

that would be bad, consistent friction good