Official Luthiers Forum!

I got a gift certificate for Japan Woodworker for Christmas and I was thinking about getting a 50 degree frog for my LN no 4. Does the 50 degree frog make much of a differance?

Thanks for the info, Todd. I think I'll give the 50 degree frog a try.

John

I have a LN 4 1/2 with the 50 degree frog. Huge difference planing curly maple.

It's a positive if your problem is highly figured woods, softer woods, and woods with good grain, can prefer lower angles. And there is another approach to highly figured woods that involves going very low, though obviously not with a LN. It's nice to have a bunch of options to move easily between.

I was thinking figured hardwood for the 50 degree frog. I've been putting together a low angle wood plane that I'm going to try out on soft wood.

How low is very low for highly figured woods?

John

Todd, what difference did the A2 blade make? The O1 is supposed to take a better edge with less work, but not hold it as long. Is that your experience?

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Short: definitely 50.

Long: my main plane is a Veritas low angle Jack with 2 blades, giving 37 and 50 degrees. The 35 is great for jointing, and thinning any plates with little runout or no interlocking grain or figure. As soon as you hit an area against the grain you get some really nasty tearout. It still works for runout tops as long as you avoid the joint and rotate the plate before planing each half separately.

The 50 deg blade works much much better with the problem plates, resulting in very limited tearout that can be scraped or sanded with not much effort. Recently I bought a 60 deg wooden smoother too which works great in between the 50 and the scraper, as any tearout is reduced to a minimum.

_________________
Build log

Shaptons specifically, or any high end stones?

Another option might be setting up a second iron for the frog you already have. You could hone a micro bevel on the top surface of this second iron, thus giving you a 50 degree angle of attack. You would save this iron for figured woods only.
I have never personally tried this, but I've seen it recommended many times in journals such as FINE WOODWORKING, and also on other builder's forums. It might be less expensive. In any event, it's an option you could consider.

That's what I do now. Although it's not exactly and apples to apples comparison because I have a back bevel on my older Stanley plane that has it's original blade. Still, sometimes it seems to cut better.

I guess one advantage of the the 50 degree frog is ease of sharpening (no back bevel). Does the frog have other advantages over the back bevel?

John

I became intrigued about back bevels after reading an article on the Fine Woodworking web site a couple of years back - mainly to justify my plane collecting habit:

http://www.finewoodworking.com/FWNPDF/011186096.pdf (you will need a subscription to view it of find someone with a subscription who can download it and send it to you - not that I condone that kind of behavior )

The article reinforces the advice you've already been given, in that the harder or more figured the wood is, the steeper the cutting angle should be. Remember the standard 45 degree angle was a compromise cutting angle for plane makers to produce their planes at, but it wasn't always the standard. Garrett Hack covers bevel/cutting angles on page 46 of "The Handplane Book":

45 degrees = common pitch
50 degrees = york pitch
55 degrees = middle pitch
60 degrees = half pitch

so, I messed around with back bevels and found it helped a ton. I did some side by side comparisons with pine, cherry, and quilted maple. As expected, the common pitch did the best on the pine, the york pitch did the best on the cherry, and the half pitch did the best on the quilted maple. It felt like once you got beyond 65 degrees, you would achieve the same results with a scraper or scraper plane.

I think the issue is that sharpening an iron with a back bevel may take an extra step every so often to keep up with it. Also, trying to hone a 5 degree back bevel can be a little challenging - even the Veritas MKII honing guide only does back bevels as shallow as 10 degrees, so you have to make your own jig to get that low of a bevel. And, hopefully your stone is long enough Ultimately, it's easier to have a 50 degree frog and just hone your iron normally. The other option is a bevel up plane with multiple irons honed at different cutting angles. Lee Valley offers this for their bevel up, low angle planes. The problem with that approach is that you can't hone a micro secondary bevel for easier honing. Otherwise it's a good system too.

I think one advantage to lutherie is that you typically use quarter sawn stock. Not that I have much experience with lutherie, but I have found quarter sawn wood planes with less tear out for me that flat sawn. On the other hand, a friend went to a woodworking show recently and was telling me he saw a plane demo that really impressed him. The instructor taught them that that if you keep the plane mouth tight, the iron sharp, and the cap iron well tuned and 1/64th from the iron's edge, than you can plane any wood in any direction without tear out. I remain skeptical, of course, because that would mean you only need one smoothing plane, and where's the fun in that

again, I'm a brand spankin' new newbie when it comes to Lutherie so I'm sure there's some particulars about this that I know nothing about, so take my advice for what it's worth. with reading Cupiano's book, I've just been excited over the prospect that I need to set up another plane with a toothing blade. ebay here I come!!!!

hope this helps,

Mike

Monster sharpness minimizes tearout, of course, but it does not last for long. And before doing final smoothing, one needs to scrub off the bulk using a deep cut and a more open mouth, resulting in large tearouts again. So imho a higher angle is our better friend, for the nasty hardwoods at least. On softwood nothing beats the smooth feel of using an ultra sharp low pitch plane.

_________________
Build log

Why couldnt you hone a secondary bevel on a number of different angle bevel up plane blades ??? all it does is change the angle by one degree -

I have 3 LV bevel up planes - block, smoother, and jack ..I hone them all at 45/46 micro secondary, so I get a cutting edge sitting at 58 .. I use them this way for everything.

_________________
Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

" The other option is a bevel up plane with multiple irons honed at different cutting angles. Lee Valley offers this for their bevel up, low angle planes. The problem with that approach is that you can't hone a micro secondary bevel for easier honing. Otherwise it's a good system too."

Why is this? I use larger format bevel-up planes and you just account for the secondary bevel in the total angle you are shooting for...

From my perspective, the bevel-up planes should be given a look at if one is considering buying a plane with a steeper angle frog. They are a different feeling animal when you're using them (center of gravity, weight, etc..) compared to a bench plane, and some people just won't like the feel of them, but I have found that I really like them and the fact that you can easily make the cutting angle whatever you want is pretty cool - a couple blades and you're ready for just about anything. I replaced my Stanley #605 and #607 with a Stanley #62 and a Lie Nielsen Low Angle Jointer and wouldn't go back. My smaller block planes (#65, #60, LN102, #101) have the bevels ground to varying angles and a reach for them for things other than what they were originally intended. Offers a lot of possibilities for varying the cutting angles for different planing scenarios.

Just my $.02

Regards, Peter Z

Sorry, I realized after I typed that line that I should've clarified my point. Absolutely, you can hone a micro bevel on a bevel up iron and the change in cutting angle is typically insignificant. My only point to make a distinction between the two styles is because a micro bevel on a bevel down plane will not change the cutting angle. It will, however, on the bevel up iron. If you are trying to achieve a specific cutting angle, then you will in fact increase it by putting a secondary bevel on a bevel up iron, albeit only slightly.

I have quite a few smoothers because I like buying antique planes and tuning them up. It makes more sense for me to hone back bevels on bevel down planes because that's most of what I have on hand and it is a sick, twisted way to justify all of them to my wife. I do have a Veritas bevel up smoother among my arsenal and love it also.

You can go back bevels, high angle frog, or bevel up all with good results. The point really is that harder and more figured woods plane much better with higher cutting angles. You might still find that your softer woods will do better with common pitch or lower so you might find it helpful to keep some of both around.

Mike

Mike - people are talking about putting a micro bevel on the back (which becomes the top) of the blade in a typical bench plane - in order to change the cutting angle (of course you could micro bevel the bottom too, but it changes nothing as you note) - so back bevel the blade 5 or 10 degrees changes the plane from 45 to 50 or 55 degrees cutting angle

_________________
Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Tony, I was talking about back bevels (on a bevel down plane) as opposed to secondary bevels (on a bevel up plane) in response to some comments about my first post in this thread.

Filippo - good question. I've never used a plane with a high angle frog, just common pitch planes with back bevels or a bevel up plane. In theory it shouldn't make a difference but you know how these things go - I'm certain someone would find it feels better. There are so many variables when it comes to fine tuning a bench plane and the preferences can become very individual. Ultimately the cutting angle is the cutting angle however way you achieve it, and if all other variables are equal (iron hardness and sharpness, well tuned cap iron, etc.) then there shouldn't be a difference, aside from the added expense of buying a separate frog.

The feel of the plane with a high angle frog is different; harder to push/pull and more demanding of good technique to avoid chatter. The difference can be pretty subtle with a very sharp iron taking wispy shavings but is it very obvious when hogging off thick spills with a dull blade.
For heavy work, you can compensate somewhat by adding more camber on the blade.

-jd

Filippo,
There might be a difference . Two planes, Plane A : 45° ramp with a 30° honing angle and a 10° back bevel = 55° cutting angle

Plane B : 55° ramp with 30° honing angle and no back bevel = 55° cutting angle.

If you draw it out it seems as if the back bevel iron (plane A) has more steel behind the cutting/scraping forces. Things get so thin right where the cutting happens it might be moot but it looks like the blade would be more supported.

OTOH I have thought about grinding and honing my irons at 40° on my bevel down wood planes. Cutting angle would be the same, what ever my ramp is, but I have wondered if the blade would hold up better. Especially with scraper planes. Thing is my tools work well and any problems are me not the tools so only so much time and energy for tweaking.
Link

_________________
Cut to size.....Beat to fit.....Paint to match.

I got the 50 degree frog and finally got around to installing it on No 5 plane. I've tried it out on some wild grain koa and it seems to work well. I tried to do a A/B comarison with my no 4 plane that has a 45 degree frog using the same blade but I couldn't really come to any conclussions that I trusted. I think I need more time with it in more situations to really get a feel for the difference.

Thanks for all the advice.

John