Thread: HNT Gordon video - bevel angles

Hi DW,
This morning I sharpened an O1 blade at 28° just like in my study than plane cherry for 100,200 and 300ft at 0.001" thick (finishing work). I took pictures with my microscope of the bevel and videos for the back.

In normal planing for finishing work I would have resharpen at a max. of 250ft which is quite a lot I think. I have seen chipping many times with this microscope but there is none after this test. Maybe an A2 blade is more prone to chipping? I'll have to look into that and see.

There is no end with this kind of test...type of steel, sharpening angles, type of wood.

The surface finish, no matter how I look at it, is as good as it get.
Bevel side after 300ft.jpg
The videos will eventually be on my website.

Normand

A2 is a lot more likely to chip, you're right.

I tested the irons I referred to at 2 thousandths on hard maple. I do find the same lines on cherry, though. It's uncommon for me to plane much at 1 thousandth.

You're also right that the tests have no end if you want to look at all variables. I think it's more important for people to experiment and use what they see in the context of work rather than rely on things posted on the web (as in, just because I mention that I see chipout below about 33 degrees doesn't mean I expect that I should shout down anyone who doesn't agree - warren says he uses 30 degrees. I still will hone as I've been honing).

Steve Elliot's work agrees with what I've seen. Whose is more reliable, his observations or yours? I don't know. His match mine, thus I'll go that way.

In terms of feet planed, I likely plane more than 250 feet with a vintage stanley iron, but I've never measured it - you're finding out that trying to quantify all of these things is a pain. I quantified the use of the A2 irons I tested and never anything else (other than once I had a bunch of panels to plane and compared hock O1 to A2 and found the A2 went for more panels before it needed to be resharpened - bit surprise there).

As far as finding microchipping and unacceptable surfaces, Brian Holcombe found the same thing with his iron, and he is sharpening by hand including grinding, so stopping to sharpen all the time is more problematic for him than it would be for me. You can see the surface he expects by looking on his blog and at his work. I suggested he stick his iron in a guide and sharpen at 34 degrees, and the problem he referred to was eliminated. You could find his discussion of that on youtube if you have to.

I'd imagine I would see lines in what you're working, but that's just supposition on my part. I don't know what magnification you're looking at, but I wouldn't judge lines on the work by the iron, I'd look at the work.

Context of edge life, now that I know what angles I sharpen to. (about 30 degrees on planes intended to hog and 33/34 on smoothing planes, etc).

Three weeks ago, i refinished a segment of floor in my house. It was carpet butted to carpet. In order to finish the job, I had to strike about 20 feet of mouldings for the floor where it meets carpet as I could no longer rely on carpet to carpet. Doorways where it meets carpet or tile or synthetic rolled floor in the kitchen, etc. Home depot had pre-stained and finished trim that would've sort of worked and looked nice, but the four types I needed would've been somewhere between $200 and $300 which I thought was kind of ridiculous.

For 14 feet of those mouldings, that involved cutting a 1/2 x 1/2 inch rabbet with a moving fillister plane, beveling the back side above that rabbet else your feet would meet a 90 degree corner) and then putting a substantial bevel on the front of the moulding 1/2 inch tall and 1 1/4 inch wide.

The wood is new growth red oak, which is about as hard as hard maple, but porous (oak being one of the woods where new growth is harder than old growth).

The other 6 feet of moulding required a 1" by 3/16th rabbet on the bottom, and beveling in both directions on the top. the stock that I used was 3/4th inch and for the last two it had to be planed down to just under 1/2 inch before the bevels were cut.

I used the following planes:
* moving fillister (I didn't sharpen it, but it was sharp before use)
* house made try plane with a vintage hearnshaw laminated double iron set (I didn't sharpen it, it was probably halfway through a sharpening cycle)
* ulmia double iron rabbet plane (to clean up the fillister work) - wasn't sharpened, but not used heavily so it doesn't matter
* Stanley 4 with an O1 iron that I made and heat treated (its' probably 60 hardness - I didn't sharpen it, but it was early in the sharpening cycle)

I did cut part of one rabbet with a metal moving fillister plane, but gave up on that as it's far more effort than a wooden one for hogging.

I did not resharpen any of these planes. All of the mouldings are 2" wide, and here's my point. I did not resharpen any of these planes when I did this work. I sharpened the moving fillister and the smoother after I was done as a courtesy to myself so that they're sharp the next time I use them.

The smoother had not taken any damage in the work, I didn't look at the iron on the try plane (it was set to cut deep is it is an ideal plane to thickness 2" wide sticking and hog off a bevel). The moving fillister plane took significant fine damage at the edge, but not enough to affect heavy use (it wouldn't have sustained the same damage if it was sharpened at 33/34 degrees, but maybe it would've been less desirable to use as the clearance disappeared, who knows?). by fine damage, I mean small nicks, etc, that cause anything other than a thick shaving to come out segmented and leave pretty pronounced lines in the work.

So as much as we want to argue about all of this stuff, I was able to do several hours worth of work cutting these mouldings, both coarse and fine, without sharpening anything. If people like me dismiss the kinds of single-variable tests that rely on specific conditions, this is why. It's not that hard to figure out what works in a shop and let laziness be your guide. If something doesn't work well, we'll figure it out in sweat and take care of it. I had other nuisance problems with less than perfect wood, but none of those had to do with clearance.

For the rest of the folks who want to rely on a collection of single-variable tests (some of which conflict) so they have something to post about, or something to think about as they're feeding wood through a jointer and avoiding doing anything interesting, like making their own trim or mouldings, I can't really offer much. They can continue to argue in the comments sections of blogs. Until I can outlast my tools' edges (which i cannot do at this point) with stamina, who really cares about that stuff? It doesn't keep oak from bowing when sawn or having grain running different directions at each end.

The rest of you guys, let me know a situation where you have been working on something real, doing more than removing plane chatter marks, and found either the tools were not up to your abilities or the advice of a serious user just really put you in a bind such that your rate of progress was halved.

Its important to bear in mind that when you listen to individual recommendations on preferred bevel angle to maximize edge retention, the type of steel being referred to is clearly outlined. As an example, the properties within A2 steel necessitate a much steeper bevel angle than would normally be recommended for most other types of tool steel.

Stewie;

O1 vs. A2

From what I've read outside of the Forum it seems that one advantage of 'microbevels' is that they allow faster or easier re-sharpening /dressing. If, as Normand and LV both opine, they don't add much to cutting performance then it seems that their major contribution devolves simply to easy resharpening, which is a nice characteristic to exploit.
On the subject of relief angles it appears that there is something going on. I think the questions as to why a particular relief angle are 'better' are interesting. We have some opinions and experiences but those don't really help us understand what's going on. I'd like to know more.

Steve Voigts site; The Black Dog's Woodshop

The irons are O1 high-carbon tool steel, hardened to 58-60 RC. They take and hold a wonderful edge. They come with a 25° primary bevel, then I flatten the backs add a very small 30° secondary bevel. These irons are ready to work, right out of the box.

Rob, far and away the best way to find out what you want to find out is to get a dissection scope (or something else that allows easy clear viewing) and go at it.

The statement about microbevels being for easy sharpening is true. They do not facilitate any additional edge life. The only place where they are advantageous in work is if you have a long gradual bevel to do hogging work but need a bit of extra edge strength. Sometimes a long steep bevel is just additional resistance and wedging in the cut, and other times it's a useful rail to ride (like mortising).

Originally Posted by derekcohen

One of the best blade tests was done by Steve Elliott, who has been mentioned here several times in this thread. Here is a link to his website and the tests he completed: Comparison Tests of Plane Blades

...Regards from Perth

Derek

Thanks for the link Derek. This page: (Sharpening) Using the laser reflections to measure angles is brilliant.

A short history of the 'the rest of the folks who want to rely on a collection of single-variable tests'.

https://en.wikipedia.org/wiki/History_of_science

A discourse on single variable tests.

https://en.wikipedia.org/wiki/Scientific_method

Re David Charlesworth's recommendation for a 35 degree bevel angle. (A2 IRONS)



The Ruler Trick - Page 2 of 2 - Popular Woodworking Magazine

The scientific method article is a good example of an ill formed and ill informed wikipedia article, but neither article has much to do with woodworking.

(youtube video) by DW; talking about micro chipping on A2 irons.

https://www.youtube.com/watch?v=iorPTbHZOVE

Originally Posted by rob streeper

A short history of the 'the rest of the folks who want to rely on a collection of single-variable tests'.

https://en.wikipedia.org/wiki/History_of_science

A discourse on single variable tests.

https://en.wikipedia.org/wiki/Scientific_method

Rob, I'd say that people who want to test something first need to know what problem they're trying to solve, and they also need to know how their solution interacts with other problems, as well as how other variables or conditions will affect the outcome.

In general, someone taking a scientific view of this *after* they have a lot of experience in the subject matter has a far better chance of coming up with something material and meaningful. They also have a much better chance of finding a problem that is in need of analysis. This one only rises to curiosity for beginners with no experience. If you're trying to serve the guy who is pondering sharpening a common pitch plane at 45 degrees, then that guy needs the help. For everyone else, there's nothing really material here.

If you want something meaningful, start 100 guys with 25 board feet of rough wood and the need to get that made into 10 door panels with hand planes. Have each guy do half of the pile with one setup, and half with another setup. Test 10 setups for each if you'd like, make a judgement for surface quality, and put a heart rate monitor and a stop watch on the guys to find out how much work they're actually doing.

That would provide something meaningful - of course, those users would have to be experienced, and so would the person running the test so that they could spot trouble.

We rarely see anything of that quality on woodworking, the single items we see tested usually don't offer anything material for an experienced user, and most people have enough sense from experience that if a beginner came along and proposed something stupid, they could tell them right away.

You can't hide behind "the scientific" method when you don't have depth on the subject.

Originally Posted by coffeefro

The scientific method article is a good example of an ill formed and ill informed wikipedia article, but neither article has much to do with woodworking.

I posted in response to the comment DW made dismissing 'the single variable crowd' and I think that, unfortunately, it has a lot do do with woodworking. In particular the trolling behavior that is far too common on woodworking websites such as this.

As to your criticism of the Wikipedia articles I agree that they could be better but they are nonetheless correct and very important is their easy accessibility. If you're interested in a truly excellent discussion that is quite accessible to the non-specialist have a look atThe Discoverers by Daniel Boorstin. I strongly recommend it and it's old enough now that copies can be had very inexpensively in used book shops. Here's a link to a review of the book: From Experience to Experiment. In the book Boorstin emphasizes the importance of standardized measurements and how the dissemination of those standards was critical in laying the foundation of the modern technological world.