Cutting angle for Veritas BU planes

[Mike Holbrook]

I have a BUS, LA Jack and the BU Jointer. These planes conveniently use the same plane iron, which is one of the reasons I have them. I read and reread all Derek's sharpening advice, at http://www.inthewoodshop.com. I have adopted most of Derek's sharpening techniques. I hollow grind just about everything at this point. I am a great fan of being able to easily resharpen by hand from the hollow grinds.

In the case of BU planes Derek's pages suggest grinding all BU blades at 25 and adjusting the final bevel angles as needed with micro bevels. I have two A2 and two PM-V11 blades that will fit all three planes. I ground one A2 blade at 25 and the other at 30 on my CBN wheel just to see how difficult it would be. I did not find the work very difficult and I am thinking about grinding both my PM-V11 blades at the final angles I plan to use them at. My thinking is that with 4 blades I should be able to cover most my needs without having to use micro bevels. I probably should add here that most of the work I do does not require a perfectly flat/polished surface. I am also trying to avoid having to get out a Veritas sharpening jig to precisely form micro bevels.

So with that background, I am interested in what cutting angles people find useful with these planes? Right, what work do I do...I am making chairs, tables, cabinets.....from typical southern soft & hard woods. I do work green wood but not typically with hand planes. The furniture I plan to build will be "rustic" and relatively simple to match the wood in a timber framed & log home that the wife and I are planing. I might also add that I have old Stanley planes that I do most of my coarse work with. I currently use the Veritas planes more as medium planes, which in my case may become more final finishes. I am still working out what type of final finish I want to use on this furniture, but I know I want get too precise with it. My Stuart Batty angle setting gauge has 20,25,30, 40 & 50. For some reason it skips 35. I think there is another one that has 35 though. 25+12=37, 30+12=42, so I have both of those in A2 blades. 40+12 would give me a 52 PM-V11 which might be helpful for twisted grains...I have been thinking about grinding the other PM-V11 at 30, for a final angle of 42 as I think that may be the best angle for me for general work. Before I grind those PM-V11 blades I thought I would solicit opinions.

[Prashun Patel]

You'll get better advice from more seasoned users, but I'll throw mine in for kicks:

I also own the LA Jack and BU Jointer and have several blades for them. I ordered them at different angles thinking it would make them versatile.

Like you, I tend to work with domestic (albeit northeast) hardwoods. I have found that I prefer ALL of the blades at 25p/30u. I only do the microbevel to speed resharpening. I much prefer the ease with which the shallower angles push through vs the higher angles. If I worked with trickier woods more regularly, I might consider going higher. Having them all standard makes remembering, and resharpening less stressful for me too.

[Mike Holbrook]

I was hoping to hear from you Prashun. I have been grinding all my Stanley planes at 30 and I was considering just doing the same with my BU plane blades before I started second guessing myself. I will end up regrinding the bevels anyway as I like hollow grinds, which I find even simpler to maintain than micro bevels, once they are ground. One of my BU planes came with a 38, which I did not realize was the standard blade for that plane, so I was planing to regrind it anyway.

Good to hear that my original idea is working for you.

[Prashun Patel]

I'd wait for the others to chime in. I honestly am squarely in the middle of my journey and am experimenting just as much as you are.

I will say that each year as my sharpening skills improve, my planing results work better and better without too much tweaking. I have also gotten much better at using a cabinet scraper (again because I am learning how to sharpen it better and better) so my need for specialty blades for tear-out has diminished.

Cabinet scrapers are cheap and wonderful tools, BTW.

[Patrick Chase]

I have a BUS, LA Jack and the BU Jointer. These planes conveniently use the same plane iron, which is one of the reasons I have them. I read and reread all Derek's sharpening advice, at http://www.inthewoodshop.com. I have adopted most of Derek's sharpening techniques. I hollow grind just about everything at this point. I am a great fan of being able to easily resharpen by hand from the hollow grinds.

In the case of BU planes Derek's pages suggest grinding all BU blades at 25 and adjusting the final bevel angles as needed with micro bevels. I have two A2 and two PM-V11 blades that will fit all three planes. I ground one A2 blade at 25 and the other at 30 on my CBN wheel just to see how difficult it would be. I did not find the work very difficult and I am thinking about grinding both my PM-V11 blades at the final angles I plan to use them at. My thinking is that with 4 blades I should be able to cover most my needs without having to use micro bevels. I probably should add here that most of the work I do does not require a perfectly flat/polished surface. I am also trying to avoid having to get out a Veritas sharpening jig to precisely form micro bevels.

Derek's approach of using 25-deg blades with high secondary bevels is related to camber. There are a couple things that make it hard to camber a high-angle blade for a BU plane:

1. Low-bed-angle planes need more camber (tighter radius) than high-bed-angle ones. For example, if you want the center of a 2" blade to cut 30 mils deeper than the corners, you would use a 16" radius on a plane with a 45-deg bed, but you would need to use a 5" radius on a plane with a 12-deg bed. This is so because depth_of_cut = depth_of_camber*sin(bed_angle).

2. The blades for BU planes are physically thicker than those for BD ones, so you have to grind more material away at any given radius.

Taking both (1) and (2) together, achieving any given depth of camber requires many times more work on a low-angle BU plane than on a BD one.

That's where Derek's trick helps: If you want to camber a high-angle blade for a BU plane the easiest way to do so is to start with a low primary bevel (he recommends 25 deg) and only camber the high-angle secondary bevel. I've been doing this with my bevel-up Jack all along (it's a fairly obvious optimization once you understand the problem), and it works beautifully.

[Chris Hachet]

I'd wait for the others to chime in. I honestly am squarely in the middle of my journey and am experimenting just as much as you are.

I will say that each year as my sharpening skills improve, my planing results work better and better without too much tweaking. I have also gotten much better at using a cabinet scraper (again because I am learning how to sharpen it better and better) so my need for specialty blades for tear-out has diminished.

Cabinet scrapers are cheap and wonderful tools, BTW.

Cabinet scrapers are fantastic...and I am with Prashun.....Sharp and 30 degrees seems to work well with most north American hardwoods for me regardless of the bevel orientation.

[Patrick Chase]

Cabinet scrapers are fantastic...and I am with Prashun.....Sharp and 30 degrees seems to work well with most north American hardwoods for me regardless of the bevel orientation.

Maybe it's just me but I find that even the best-tuned scraper leaves a somewhat "fuzzier" surface than does a 45-deg plane, with or without close-set cap iron. Others whose opinions I trust have described the same thing, but we could all be missing something.

FWIW I hone my scraper corners to #4000 or higher. I burnish the faces with medium pressure, and then turn the hook with fairly light pressure, starting perpendicular to the face and increasing over several strokes to ~5 deg of inclination. For good surface quality I find that small hook at relatively low angle is best. I do not "recycle" hooks - I re-joint and polish the surface and turn a new hook.

[Mike Holbrook]

Patrick I think I get the reasons for grinding BU bevels at 25 and doing micro bevels. The thing is I do not find grinding bevels in thicker BU plane blades objectionable with my current CBN wheel grinding set up. I ground one of my A2 blades at 25 and another at 30, using my current CBN set up, just to see what it was like, takes maybe 15-20 minuets I guess. Both blades needed to be ground anyway as they had weird bevels from me experimenting with other sharpening methods on them for years.

I believe Derek mentions somewhere that he prefers to hand sharpen, as do I. The issue with doing micro bevels via Derek's method is he suggests that a jig is needed to get those micro bevels just right. I am not too concerned with getting perfectly flat surfaces for most of the work I do, so my thought is I may be able to hand grind slightly cambered bevels and not have to employ a jig to do those micro bevels. With four blades, even if I grind a couple at a little higher angle, I am thinking I might be able to avoid needing micro bevels. Derek obviously deals with some exceptionally difficult wood that I probably will mange to avoid. I am also thinking that if need be I could add a micro bevel to my hollow ground blades. I asked Derek, who has also adopted CBN wheels, if he had tried hand grinding BU blades. His answer was that he has been working with and testing Veritas Custom BD planes and has not taken the time to try that yet.

Given the fact that I plan to regrind the bevels on the other two PM-V11 blades anyway, my question simply becomes whether or not to grind them all at 25,30 or not. I experimented with one at 30, because like Prashun mentions above, I thought it would be nice to just grind everything at 30. I grind all my Stanley's at 30, as I believe many people do.

Yes, I have scrapers but I do not usually work to that fine a finish. I tend to finish with: planes, spokeshaves, rasps, drawknives instead.

[Derek Cohen]

Mike, as Patrick notes, the "low primary bevel/high secondary bevel" strategy is aimed at creating camber. One could use a high primary only bevel, as per the blades sold by LV, if you planned not to use camber. The strategy I outlined a good many years ago now is to reduce the effort in honing the camber by reducing the amount of steel that needs to be wasted.

One can use other methods to create a camber, but they will require more effort. I have BU smoother I built, an infill with a 25 degree bed (the LV and LN planes have a 12 degree bed). With freehanded sharpening on a 35 degree hollow grind, I can put a great edge on the blade and achieve a 60 degree cutting angle. Honing this blade does take more effort. Nevertheless it is doable.

The camber on a BU smoother is still very fine, and the reason I do not attempt to grind this in is that it is impossible (for myself) to achieve something like this on a grinder, CBN or not. I use a honing guide for BU blades because it is extremely difficult to judge the difference in a secondary micro bevel between 35- and 50 degrees. In practice they make a very big difference on the woods I work.

Regards from Perth

Derek

[Mike Holbrook]

Hi Derek thanks for the input. I missed it at first and just found it.

So far my confidence level with the Veritas MK.11Honing Guide System I have is very low and oddly enough after spending a good deal of time working on my CBN wheels my confidence level them it is very high. The SB tool rest I have been using is very steady and I seem to be able to do much more accurate work with it on the CBN wheels than I have ever been able to achieve in the past. I also have the LV grinder tool rest that has the guide system for locking a plane blade in place and moving the blade back and forth across the wheel at a consistent 90 degrees.

I am still trying to figure out how to make very small cambers in smoothing plane blades. The videos I have seen, done by Schwarz and I think a couple others on YouTube, show the smoothing plane blade held up against a 4" square. The idea being that one should be able to see just a little light, hopefully for equally small distances, on either side of the blade, with the center of the blade just touching the arm of the square. This is the only system I have been able to use to see the results of my efforts, regardless of how I am trying to make the camber.

I believe Derek and some others have mentioned leaning on one side of a guide or the other and counting strokes as a method that may work. Thus far I have not been able to achieve a perceptible consistent camber in a blade using this method. So thus far, I seem to be able to produce the most accurate repeatable results on my CBN wheel. I fully realize that this does not mean this is the best system. It, so far, is the system that has produced the most accurate results for my admittedly lame but growing skill set.

Actually though, I was honestly just trying to figure out what actual bevel, regardless of whether the bevel is a micro bevel or primary bevel works well for smoothing planes, particularly BU smoothing planes. I have both BU & BD smooth planes but there is more information around on the BD planes with chip breakers and how to set these up.

I am not sure if the thicker blades on BU planes, without chip breakers, might, largely due to the lack of a chip breaker, benefit more from a little higher bevel? I think Schwarz talks about setting a Veritas Custom #4 at 50 degrees, primary. Derek mentions, above, 60 degrees as the bevel he set up on the infill he made.

I know that chip breakers and higher bevels are two methods for handling difficult grain. I may be reading between the lines here but, it seems like those who use BU planes for smoothing, tend to use a little higher bevel. I am guessing that these higher bevels may be to help with difficult grain with planes that by design have no chip breaker? I am trying to figure out what degree bevel might work for me on my BU smoothing plane blade. Maybe an additional 5-10 degrees would be advisable, simply because it is a BU plane?

[Mike Holbrook]

I know that there are quite a few other posters out there using BU planes. It seems that most posts about smooth planes end up in a discussion of chip breakers and how to set them. As BU planes have no chip breaker this information does not apply. I have probably over referred to Derek's sharpening advice in regard to BU planes. The reason I keep doing this, and reading and re reading his work is it seems to be about the only information available on methodologies for sharpening BU planes. It seems that all posts about sharpening BU planes get referred back to Derek's method of using micro bevels as a work around to grinding the extra thick BU blades. I myself habitually refer new BU plane users to Derek's information. As Derek mentions above he has been using and testing the new Custom Veritas BD planes for some time now, which I believe means that is where his focus and interest lies. He mentions above that his article on grinding BU plane blades to 25 degrees and adjusting final bevel angles with micro bevels is several years old now.

I suspect there is a reason LV/Veritas delivers their BUS smooth plane with a blade with a 38 degree bevel, while they deliver their SBUS, LA smoother, LA Jack and BU Jointer with 25 degree bevels typically. I know we can order blades with different angled bevels with these planes, still the BUS smoother seems to be the one that, unless the orderer specifies a different blade, comes with a 38. My guess is that LV sees the BUS as a heavy duty smoother that, due to its weight and low center of gravity, can power through tougher grains at higher bevel angles. My BUS was delivered with a 38 degree PM-V11 blade. I am trying to figure out how, if, I should grind a different bevel in that blade.

The missing piece for me in all this is when Derek wrote his article on sharpening BU plane blades I think he was grinding bevels on a Tormek. Now I believe Derek grinds most of his bevels on a CBN wheel. I fully understand why Derek might want to minimize the amount of grinding on a Tormek. I would rather take a beating than try to regrind another BU plane blade on a Tormek. I should add that after years of struggling with it I found a unique issue with my Tormek that I believe to be the cause of most of my problems grinding bevels, still....

On the other hand, I do not seem to have any trouble grinding fairly accurate bevels in A2 BU blades with my current CBN wheels and rests. I don't think Derek has tried grinding BU plane blades on his CBN wheels yet. Even if he has, would he take a PM-V11 BU blade that came at 38 degrees, regrind it to 25 with his CBN wheel and then use his Veritas jig to establish a 38 degree micro bevel? Because that is the question I am asking myself. Of course a 38 degree blade in a 12 degree BU plane yields a 50 degree, York pitch, bevel. I suspect that a York pitch in that plane may be a great way to set it up, which would be why Veritas typically delivers that plane with that blade.

I also know Derek routinely works wood that is much more challenging in terms of grain direction and hardness than what I will probably be working. Derek mentions making a "semi, 25 degree bed" BU plane with a combined bevel of 60 degrees. My guess is a woodworker like me or the "normal" SVC poster might not need quite as much bed angle as Derek finds useful. From what I have read over the years the average poster on this forum is more likely to use a 45 degree frog on a BD plane or a 37 degree, combined bed & plane blade bevel, on a BU plane. Many SMC posters seldom, if ever, vary their working angle on their individual planes. Derek, on the other hand, might very well regrind a 38 degree BU plane blade to 25 then make a 38 degree micro bevel, just so he can vary the micro bevel easily for the greater variety of woods he works. Another words, Derek may have reasons to grind blades the way he does that might not apply to everyone.

I have the greatest respect for all the work Derek does and the time he takes to post his suggestions for the benefit of those of us with far less experience. I was hoping to hear from other SMC posters, particularly those who use Veritas BU planes like the BUS, who may be working woods more similar to the woods I plan to work with. My guess is many SMC posters leave plane blade bevels the way they come, particularly those blades made by premium plane manufacturers like LV & LN. Using blades as they arrive would greatly reduce their need to grind bevels. I do suspect many have specific planes, like the BUS, set up to handle difficult grains.

I am guessing my OCD thing with grinding bevels is even more unique than I am assuming it is. I suspect my collection of weirdly beveled plane blades is fairly unique among SMC posters. I have finally come up with tools and a skill set I can successfully employ to rectify my backlog of strangely beveled plane blades. At the same time I am trying to come up with a consistent as possible system for all my plane blades. Although I am still open to suggestion, I find hollow grinding to offer substantial time savings, largely due to the fact I can quickly re hone (not grind) for long periods of time after making the original bevel.

I fully realize that my grinding system may be fairly unique and I am not trying to press that system on others. I am simply interested in hearing what all those other BU plane users out there in SMC land use in terms of combined (bed + bevel angle) cutting angles as I am in the process of regrinding lots of different BD & BU plane blades. The BU planes are the ones I am a little puzzled with and it seems to be hard to discuss this topic with out getting off topic on: chip breakers, grinding techniques for BU planes, scrapers.....