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View Full Version : What can't a bevel up plane do as well?



Kenny King
06-25-2008, 10:10 AM
I'm looking for a 4 1/2 smoother plane. When compared to say a bailey 4 1/2 or a bedrock 604 1/2, i understand that i BU plane with a high angle, say 50 deg. is good on difficult wood. Is the converse true? Could I use a BU plane as a regular smoother for non-difficult wood? This assumes i use the bevel angle as on the bailey but fitted to a BU plane. (not sure what the angle is off hand).

Anyhow, to get to the question... is there and advantage that the bailey or bedrock would have with it's standard angle over the BU plane for general smoothing in non-difficult wood?

Thanks.
Ken

Derek Cohen
06-25-2008, 12:47 PM
Hi Ken

There are pros and cons.

With regard to planing performance, the BU planes can do all the BD planes can do and much more. If you want to compare BU to a LN #4 1/2, then the range of the latter is between 45 degrees to 55 degrees, depending on the frog you use. Of course, with gthe aid of a backbevel the BD plane can get higher than 55 degrees, but this does make sharpening more complicated (I shall come back to this point).

The BU plane not only can go higher than 55 degrees (I routinely use 62 degrees), which does make a significant difference when planing difficult grain, but the BU plane can go lower than 45 degrees. For example, when used on end grain in a shooting board, the LA Jack or LA Smoother will typicaly have a 37 degree cutting angle, which is an advantage over higher angles.

Further, both planes can be used with cambered blades. What was a complaint levelled at BU planes about the difficulty in cambering blades, was one I dismisssed (see my website for the article) with the evidence that BU blades simply require a different strategy.

So where is the down side? It depends if you are a freehander or a honing guide user.

BU planes achieve their cutting angles from the bevel angle added to the bed angle. The angle of the bevel is, thus, very important. Blades are best prepared with a microbevel on a lower primary bevel. This requires the use of a honing guide. Personally, I dislike the intrusiveness of a honing guide into my WIP, and only put up with it because the BU planes have such terrific performance.

I like hollow grinding my BD plane blades. This allows me to freehand the blades and makes stropping between honing an easy process. BD blades achieve their cutting angle from the angle of the bed/frog, and the blade, itself, plays no part in this. So it matters little what angle the blade is ground.

The other criticism levelled at BU planes is that the blades acquire a larger wear bevel than the blade on a BD plane, and thus do not hold an edge as long. This is true (it is documented), but I will argue that it is not a significant issue if you strop the back as you work, or that you hone the back a little more. In practice it has not been an issue for me. Further, there is a similar criticism that might be thrown back at BD planes - in the timbers I work the backs of the BD blades "gunk up" with resin and degrades performance equally.

As soon as you have to resort to a backbevel on a BD plane to increase the cutting angle, then the same criticisms of using a honing guide apply to BD planes as well.

I have some fine BD planes, such as an Anniversary LN #4 1/2, a refurbished Spier, and a bunch of HNT Gordons, among others. They all perform very well. However, when it comes to particularly hard and interlinked timber, only the BU planes can produce that extra by virtue of their high cutting angles. Similarly, I prefer the lower angles on a shooting board as this produces a smoother surface. If you are not going to work with exotics or difficult timbers, then these differences, and all associated pros and cons, will not be experienced.

Regards from Perth

Derek

Johnny Kleso
06-25-2008, 5:36 PM
I have very few BU planes and if I run into a tricky grain I bust out my $5.00 card scraper ....

Yes all you need is another blade to change the angle of cut on a BU plane but in most of thse cases you will be taking a very light cut that you could use a 212 scraper plane or card scraper, as woodworkers have done for the last 150+ years...

There are some pluses to BU planes.. I just think buying old Stanleys with a retro fitted blade is eaiser on my pocket..

Tim Put
06-25-2008, 8:12 PM
BU planes is that the blades acquire a larger wear bevel than the blade on a BD plane, and thus do not hold an edge as long. This is true (it is documented)

Where is this documented? I would like to see the details the test (both the methods of testing and the exact method of sharpening applied).

Wilbur Pan
06-25-2008, 8:51 PM
The BU plane not only can go higher than 55 degrees (I routinely use 62 degrees), which does make a significant difference when planing difficult grain, but the BU plane can go lower than 45 degrees. For example, when used on end grain in a shooting board, the LA Jack or LA Smoother will typically have a 37 degree cutting angle, which is an advantage over higher angles.

You can always skew a BD plane, and Presto! Instant low angle plane!

Derek Cohen
06-25-2008, 9:23 PM
Where is this documented? I would like to see the details the test (both the methods of testing and the exact method of sharpening applied).

Hi Tim

Brent Beach has done some testing and displays the process and results on his website. Here is a link, but you will need to search for more yourself:

http://www3.telus.net/BrentBeach/Sharpen/bladetest.html

Regards from Perth

Derek

lowell holmes
06-25-2008, 9:54 PM
I have a LN 4 1/2 (standard pitch) and a LV BU Jack. I have all of the irons for the LV. The 4 1/2 could not handle the grain on a curly maple rocking chair I recently made. The LV BU with the 50 degree bevel handled it quite well. I use the LV BU on the shooting board. It will also smooth, but not quite as well as the 4 1/2.
If I could only have one, it would be the BU plane.

Derek Cohen
06-25-2008, 11:39 PM
I have very few BU planes and if I run into a tricky grain I bust out my $5.00 card scraper ....

Yes all you need is another blade to change the angle of cut on a BU plane but in most of thse cases you will be taking a very light cut that you could use a 212 scraper plane or card scraper, as woodworkers have done for the last 150+ years...

There are some pluses to BU planes.. I just think buying old Stanleys with a retro fitted blade is eaiser on my pocket..

Hi Johnny

I, too, use cabinet scrapers and a #112 scraper plane. These definitely have a place. Mostly they come out for small sections of tearout that are difficult to plane owing to pockets of reversing grain (You should see some of the stuff I have at this time - pretty ... awful :) ).

The downside of scrapers is that they do not leave a smooth finish like a plane does. So I would rather use a plane. A high cutting angle can produce a far better finish than a cabinet scraper or even a scraper plane - even when the shavings from the scraper blade look like plane shavings ...

http://i13.photobucket.com/albums/a262/Derek50/Planes/Scraper%20planes/112LNTasOakshaving1.jpg

I have one of those "old Stanleys", a #62, and it has a LN blade. It is one of my favourite planes. Light and great feel. But I use it less and less as the grey cast iron is fragile compared to the ductile iron of LV and LN, and the sole is thin (in the BU design) and has a reputation for cracking. Better use a modern plane in this instance.

http://i13.photobucket.com/albums/a262/Derek50/Restoration/Stanley%2062/Stanley62completed.jpg

Regards from Perth

Derek

Tim Put
06-25-2008, 11:53 PM
Hi Tim

Brent Beach has done some testing and displays the process and results on his website. Here is a link, but you will need to search for more yourself:

http://www3.telus.net/BrentBeach/Sharpen/bladetest.html

Regards from Perth

Derek

Yes, I've seen and read that, it's a great resource.

I have to disagree with your interpretation of his results. The wear bevel on a BU blade is identical to the wear bevel on a BD blade with the same clearance angle. The two types of blade orientation dull at exactly the same rate given identical edge geometry. What is, at least superficially, different is sharpening. In both cases it is the side of the blades in sliding contact with the wood that wears the most and requires the most honing, in the case of a BD plane it is the bevel that most requires honing, in the case of a BU plane it is the back that requires the most honing.

Imagine a blade only as long as the bevel honed without micro or back bevels(triangular in cross section) and some sort of magic plane that could securely hold such a tiny blade. Is it a BU plane or a BD plane? If you flip the blade over does it change?

I unquestionably agree that since it is the back that requires the most material removal in a BU plane microbevels are near necessity, but I don't think that is necessarily a disadvantage.

Simply put, the wood sees the edge, if the edge is the same shape presented at the same angle it will act the same, the wood doesn't care which surface extends back 1/4" and which one extends 6".

Derek Cohen
06-26-2008, 1:13 AM
Hi Tim

I was not necessarily citing Brent's results, just pointing you to research on BU blades and wear bevels.

But I agree with you that a wear bevel is just a wear bevel, regardless of BU or BD. The actual argument against BU blades in this instance is that one naturally hones away the wear bevel when preparing a BD blade, but that a BU blade (since it wears on the opposite side) requires extra attention and, further, will fail to cut effectively if the wear bevel is not removed.

That is why I made two points (but clearly - very clearly!) - failed to explain these ..

In favour of BU ... I strop the back of a BU blade between honings and this minimises the effect of a wear bevel.
Against BU .. I would like to strop the front of the bevel as well but this is difficult (impossible) if you want to maintain the secondary bevel angle without a honing guide.

The point about microbevels on BU blades - I'd rather have a hollow grind that I can freehand on a stone (as with a BD blade). Secondary bevels are a necessity on a BU plane if you want to camber the blade. They are not necessary if you use a straight edge. In the case of the latter set up, you can hollow grind a 50 degree bevel and freehand it. Just don't try to camber it as well :( Lastly, this issue I have with secondary bevels is not relevant to those that use honing guides all the time. Only for those that wish to freehand hone cambered BU blades with high secondary bevel angles. Unfortunately, this is the area of their greatest strength among users of timber with serious interlinked grain.

Regards from Perth

Derek

Eddie Darby
06-26-2008, 7:43 AM
BD planes tend to be heavier than their BU counter-parts. Ug heavy is guud!:D

BD planes adjust easier on the fly, since the adjuster is right at the index finger ready to be tweaked a little to zero-in on that ideal shaving that you are trying to get. BU are not as user friendly in this mode.

Who says that you can only have multiple blades for BU planes. You can own more than one blade for a BD if you want to play with back bevels to attack difficult grain.

Most people train for BD sharpening, so if you are going to use a BU you need to make sure that you have a sharpening system/method that will accommodate the difference. Not a real show stopper!:rolleyes:

Derek Cohen
06-26-2008, 8:05 AM
BD planes tend to be heavier than their BU counter-parts. Ug heavy is guud!

Then you have not used a Marcou S15! :)

http://i13.photobucket.com/albums/a262/Derek50/Planes/Marcou%20S15/MarcouRockMapleshavings1a.jpg .... against the grain!

Regards from Perth

Derek

Alex Yeilding
06-26-2008, 11:50 AM
Where is this documented? I would like to see the details the test (both the methods of testing and the exact method of sharpening applied).
Tim, I share your apparent skepticism here, but wonder if it's how he problem is expressed. It is obvious to me (which I will admit sometimes translates to "I have missed something") that the wood doesn't "care" whether the underside of the wedge of metal cutting it is the first few .001"s of a bevel or of a flat back. So I don't see how the wear bevel could be different. I think the difference is in removing the wear bevel. Here's my thousand words' worth. The irons are identical, both ground at 30 degrees and bedded to present a 45-degree angle to the wood. The wear bevel illustrated is parallel to the wood, and is identical in each case, although its orientation w.r.t. the iron's geometry is of course different. Note the amount of honing needed to get back to the original line in each case (the blue line).

91405

Alex Yeilding
06-26-2008, 12:00 PM
You can always skew a BD plane, and Presto! Instant low angle plane!

True for freehand planing, but without some kind of sled to hold your plane at an angle relative to its direction of travel, this solution won't work with a shooting board. (Despite what is often written, a ramped shooting board does NOT result in a skew cut--the plane still moves at 90 degrees to the edge of the iron.)

Alex Yeilding
06-26-2008, 12:16 PM
Who says that you can only have multiple blades for BU planes. You can own more than one blade for a BD if you want to play with back bevels to attack difficult grain.
Very true. However, at the same time, you are widening the mouth, which is probably not what you want to do. Most BU planes have mouth adjustments that are CONSIDERABLY easier than adjusting the frog. In fact, it is very easy to adjust the mouth as you fine-tune depth of cut, even with the same iron.

One more difference--BD is MUCH more suitable for wedged planes, since component of force along the blade (pushing it out of position) is much less with BD.

Eddie Darby
06-27-2008, 4:14 PM
BD planes tend to be heavier than their BU counter-parts. Ug heavy is guud!

Then you have not used a Marcou S15! :)

http://i13.photobucket.com/albums/a262/Derek50/Planes/Marcou%20S15/MarcouRockMapleshavings1a.jpg .... against the grain!

Regards from Perth

Derek

I guess you now know why I used the word 'tend' as opposed to the word 'are'.:D
Thanks for the nice pic!!!! I have not used a Marcou but I sure wish I had!!!!