Scraper planes

[Derek Cohen (Perth Oz)]

The decision on whether one chooses to take advantage of this conical tip feature on a Stanley type burnisher should be left for every user to decide upon.

So, Stewie, are you recommending it or not?

Phil Lowe is the only person I have seen actually use it. I cannot comment on the surface quality, since this is unseen, but the shavings I obtain appear the same as Phil's. I am very happy with the performance of my cabinet scrapers, which are created sans conical tip.

I believe that the important aspect to achieving this performance is how one creates the hook. There are two aspects of relevance. The first is first drawing the steel out, and the second is a progressive turning of the hook. One or both of these is not done at all by most of the demonstrations I have seen (in videos and at shows). Instead, what is typical is a one-time turning of the hook. That makes it difficult to control the angle, and it ends up variable, not enough in parts and too much in others. Where the hook is turned at too high or too low an angle, it will not cut, and all you get is dust.

Regards from Perth

Derek

 

[swagman]

Derek; the following scraper plane shavings are the result of using the burnishers conical tip to govern the blades hook angle. Note; the Stanley #81 has a fixed bed angle of 115*, and no tension adjuster to camber the blade. As a consequence, this type of Scraper Plane has a very fine tolerance in setting the correct hook angle on the blade. The use of the conical tip of the burnisher to control the turned hooks final angle (as recommended within the Stanley Tools Guide 1941) does offer the user a proactive advantage.

Stewie;

Hardwood;


Softwood;

 

[Derek Cohen (Perth Oz)]

What is the (surface and shaving) difference with and without the use of the burnisher point? That is what it comes down to - not whether one can make shavings, per se.

Regards from Perth

Derek

 

[patrickjchase]

My, there seem to be some rather familiar-sounding arguments on this forum...

Derek; the following scraper plane shavings are the result of using the burnishers conical tip to govern the blades hook angle. Note; the Stanley #81 has a fixed bed angle of 115*, and no tension adjuster to camber the blade. As a consequence, this type of Scraper Plane has a very fine tolerance in setting the correct hook angle on the blade. The use of the conical tip of the burnisher to control the turned hooks final angle (as recommended within the Stanley Tools Guide 1941) does offer the user a proactive advantage.

There is indeed a potential advantage inasmuch as you are ensuring a uniform hook angle by "opening up" the hook to the burnisher's tip angle. I don't think anybody would debate that point.

There are also disadvantages, however. The spring steels used in scrapers are fairly brittle to begin with, made as they are of HCS tempered to Rc50 or so for modern ones from Bahco-Sandvik, LN, LV, etc. Turning the hook on such a scraper further hardens and embrittles the steel due to strain-hardening (a.k.a. work hardening), and then using the burnisher tip to push it back the other way work hardens and embrittles it still more. Imagine bending a coat-hanger back and forth, but keep in mind that scrapers start out from a much more brittle state.

Every additional bit of work potentially causes fractures to form and grow along the burnished edge, compromising the resulting surface finish. All of this of course assumes that your burnisher's point is perfectly hard and conical. If it introduces any defects of its own then the situation goes downhill even more rapidly.

It is inexorably true that "over-burring" the edge and then pushing it back to the desired angle with the point of the burnisher will carry some increased risk of edge damage and surface quality loss, versus just getting it right to begin with. I prefer to try to hit the final angle when initially turning the burr, and don't see the incremental angular consistency and precision that I might get by over-burring and "reversing" as worth the risk of edge damage and surface tracking.

Speaking of tracking, do you think that this sort of edge damage might have something to do with the "torn" feel that you reported a few posts back in your "with burr" results? While I don't have the specific piece you're working, that isn't what I typically observe with "cleanly" burred scrapers.

 

[swagman]

and don't see the incremental angular consistency and precision that I might get by over-burring and "reversing" as worth the risk of edge damage and surface tracking.

Patrick; I think you may be overstating this concern with edge damage to the burr. One stroke with the conical tip of the burnisher is all that's required to reset the burr angle . Out of curiosity since you mentioned coat hangers. Aren't they normally made from a low carbon steel.!!

 

[swagman]

What is the (surface and shaving) difference with and without the use of the burnisher point? That is what it comes down to - not whether one can make shavings, per se.

Regards from Perth

Derek

Derek; the following shows the difference in shavings and surface condition from the use/ and non use of the conical tip of the burnisher on hardwood.

Without the conical tip. Chalk was used to highlight the tear-out that was occurring to the surface of the wood. Type I shavings.


With the conical tip. The surface of the wood shows some spotting of reverse grain but no serious tear-out. Type II shavings.


http://planetuning.infillplane.com/html ... ation.html

 

[Derek Cohen (Perth Oz)]

If you say so Stewie. How long have you been an exponent of the pointed burnisher?

Regards from Perth

Derek

 

[D_W]

Stewie - I don't use a burnisher with a conical tip. You didn't roll the burr properly on the top picture. That is an issue of yours, and not of the burnisher. Learning what the angle is and then repeating it without gadgetry is pretty easy, it's probably about 70 degrees from the length of the blade, and in my experience, it's also not particularly sensitive to pressure (the more pressure, the bigger the burr, but the scraper still works) - at least from what little I recall since I rarely use a scraper. The reason for that is that it's substantially inferior to a double iron unless you're planing veneer, and I'm sure many who use them have pretty ugly edges on the surfaces they finish. The #112 and #212 are better but still far behind a plane for most things.

At any rate, I have no trouble setting it with a round burnishing rod because I figured that I should remember the visual of the angle that rolls a proper burr. So should anyone else - especially given that it's a tool that I sharpen once every several years.

https://www.youtube.com/watch?v=Xu7doUE1caw

Discussion of the burr at 6:00 and resultant shavings around 8:30 or so. I didn't make this video just to make it. Someone else having trouble with the 80 requested it in the comments of another video, so I obliged. These things (tool setup) are simple, and we should share them as such. Just as we should share what's useful and efficient in actual work.

That said, if someone uses a burr with a conical tip because they like the "product", that's fine. It is not, by any means, required kit, though.

(credit again to David C, because he showed this simple process - more or less - in a video, discussing about what the angle should be to roll a burr on a scraper, and he provided a suggestion for the making of a jig of scrap wood for people who cannot master it otherwise, but most will find that a starting point and discard it once they've learned what looks and feels right).

 

[swagman]

Derek; attached are the contact details for Phil Lowe.

Philip C. Lowe, Director and Master Craftsman

The Furniture Institute of Massachusetts
116 Water Street • Beverly, MA 01915
Phone • 1-978-922-0615

Email • [email protected]

 

[D_W]

Oh, good lord - now phil lowe has a version of this burnisher available for purchase at $65. (Hock's lovely polished rod is $16).

Jeez. What a harsh punishment for refusing to learn something simple.

 

[Trafalgar]

Is a pointed burnisher essentially the same as a Veritas Tri-Burnisher?

http://www.leevalley.com/us/Hardware/pa ... 41070&ap=1

I have a Clifton burnisher but it's round. The Veritas burnisher does look like it would be more effective on shaped scrapers.

I have heard of using the tip/near tip of an awl to roll a very delicate burr or to get into a tight spot. A conical tip on an otherwise round burnisher might come in handy from time to time. Don't see it as a big deal one way or the other.

 

[David C]

I was disappointed with mine which was, NOT STRAIGHT.

David

 

[Trafalgar]

I was disappointed with mine which was, NOT STRAIGHT.

David

The Veritas Tri-Burnisher?

 

[David C]

That's the one!

David

 

[Trafalgar]

I'm sure they would replace it...

 

[David C]

It was purchased many years ago, before I realized the customer service was so good.

David

 

[Trafalgar]

They have been around quite a while.

 

[Derek Cohen (Perth Oz)]

For many years I have used a thin carbide rod ..

Happy with the results.

Regards from Perth

Derek

 

[D_W]

Is a pointed burnisher essentially the same as a Veritas Tri-Burnisher?

http://www.leevalley.com/us/Hardware/pa ... 41070&ap=1

I have a Clifton burnisher but it's round. The Veritas burnisher does look like it would be more effective on shaped scrapers.

I have heard of using the tip/near tip of an awl to roll a very delicate burr or to get into a tight spot. A conical tip on an otherwise round burnisher might come in handy from time to time. Don't see it as a big deal one way or the other.

The awl idea sounds nice since it doesn't carry a fat rod below the taper and would roll a burr on a very small scraper angle.

 

[Derek Cohen (Perth Oz)]

I have heard of using the tip/near tip of an awl to roll a very delicate burr or to get into a tight spot. A conical tip on an otherwise round burnisher might come in handy from time to time. Don't see it as a big deal one way or the other.

Charlie, I imagine the application for this is rolling a hook on profile blades for a #66 or similar, since that is what I have done. That is not the same as running the point along the hook on a cabinet scraper.

Regards from Perth

Derek