BU Plane Iron camber

[Petey83]

Just wondering if people have any recent thoughts on the best way to camber 25, 38 and 50 degree Veritas BU Irons. I have seen one very comprehensive guide but this seems dependent on having a linisher / fixed belt sander (I don').

I have a slight camber on 1 of my 25 degree irons but it took an absolute eternity on the 300 grit diamond plate to get it.
My thinking is to grind the camber on the bench grinders with iron parallel to the wheel and then regrind the primary bevel after getting the camber.

 

[Andy Kev.]

Derek Cohen went into that in some depth on here. It might be on his In The Woodshed website.

 

[Petey83]

Derek Cohen went into that in some depth on here. It might be on his In The Woodshed website.

it was Dereks guide i read but it seemed reliant on a linisher / belt sander. I am thinking I could try and replicate using a card template on a grinding wheel but wondered what others do now days.

 

[D_W]

Just wondering if people have any recent thoughts on the best way to camber 25, 38 and 50 degree Veritas BU Irons. I have seen one very comprehensive guide but this seems dependent on having a linisher / fixed belt sander (I don').

I have a slight camber on 1 of my 25 degree irons but it took an absolute eternity on the 300 grit diamond plate to get it.
My thinking is to grind the camber on the bench grinders with iron parallel to the wheel and then regrind the primary bevel after getting the camber.

Do you mean perpendicular to the wheel? that is how I grind irons like that, including irons when I make a jack and send it to someone (I don't leave it flat). Color your corners if need be, or just take some flat facets off the iron and then once you've got them even, round them off, then put the iron on the rest and grid at the bevel angle until the blunt edge is gone. From that point on, you should be able to maintain the camber honing, and hollow grind as needed.

I had a BU plane, but I hate the way they operate in a deep cut with a cambered iron. The iron has to protrude so far out of the mouth they just have a bad feel. I'd suggest tracking down a record 5 or something if you want to do camber work, you'll like it a lot more, and you guys seem to have planes like that aplenty.

There is no virtue in that kind of work to having a dead flat plane (actually, the premium planes have more friction) or having a really hard iron, as hardness buys you time before clearance decreases - but that critical clearance is only quick to dull softer irons with the thinnest of shavings. Those softer irons are preferable for coarse and medium work.

 

[Petey83]

Just wondering if people have any recent thoughts on the best way to camber 25, 38 and 50 degree Veritas BU Irons. I have seen one very comprehensive guide but this seems dependent on having a linisher / fixed belt sander (I don').

I have a slight camber on 1 of my 25 degree irons but it took an absolute eternity on the 300 grit diamond plate to get it.
My thinking is to grind the camber on the bench grinders with iron parallel to the wheel and then regrind the primary bevel after getting the camber.

Do you mean perpendicular to the wheel? that is how I grind irons like that, including irons when I make a jack and send it to someone (I don't leave it flat). Color your corners if need be, or just take some flat facets off the iron and then once you've got them even, round them off, then put the iron on the rest and grid at the bevel angle until the blunt edge is gone. From that point on, you should be able to maintain the camber honing, and hollow grind as needed.

I had a BU plane, but I hate the way they operate in a deep cut with a cambered iron. The iron has to protrude so far out of the mouth they just have a bad feel. I'd suggest tracking down a record 5 or something if you want to do camber work, you'll like it a lot more, and you guys seem to have planes like that aplenty.

There is no virtue in that kind of work to having a dead flat plane (actually, the premium planes have more friction) or having a really hard iron, as hardness buys you time before clearance decreases - but that critical clearance is only quick to dull softer irons with the thinnest of shavings. Those softer irons are preferable for coarse and medium work.

I already have a Quangshen no5 that is used for knocking stock down but a while back I got myself a Veritas BU jointer and then got the BU Jack for an anniversary gift so want to get them working for me. I don't need heavy camber on the irons - just enough to prevent track marks and allow me to use effectively as a jointer on edges.

 

[Petey83]

The way I did it is I cambered my blades on the bench grinder. Once you've done that it's very easy to maintain the camber by sharpening side ways on a slightly hollow stone. You need more camber on a bevel up plane because of the low angle so I also make a small rocking motion to maintain the larger camber.

i use the veritas honing guide with the camber roller so hoping that will suffice for maintaining the bevel once ground

 

[Derek Cohen (Perth Oz)]

The most important factor when cambering a BU blade is that you start with a 25 degree primary bevel. It does not matter how you get there. In the article I wrote 10 years ago, I was then using a belt sander. Shortly after this I began hollow grinding, and this is what I still do today. Just start with a 25 degree primary bevel.

The next step is to add the desired bevel angle as a secondary microbevel. The "secondary" indicates the angle (e.g. 38- or 50 degrees), and the "micro" indicates that the bevel is tiny. The easiest way to do this is with a honing guide. Any honing guide works: Veritas, LN, Eclipse. Set the desired angle and and hone away. Use the coarse stone (say 1000 grit waterstone) to create the secondary and add in the camber at the same time. I then move through the other grits (in my case, 6000 and 13000). Flip the blade and polish the back. Done.

The reason for this process is that high angle bevels have too much steel to remove when cambering. Reducing the steel to a manageable amount is the reason for the 25 degree primary bevel. Don't even try grinding a 50 degree angle into a camber - I freehand all my BD plane blades and chisels, but give up when attempting this on a 50 degree bevel. It is just too awkward. The 25 degree primary makes cambering easy - it becomes no different from a BD plane blade. The use of a honing guide just makes it easier to just about 50 degrees. BU does require a more accurate angle than BD.

Here is a link to the original article: http://www.inthewoodshop.com/WoodworkTe ... lades.html

Regards from Perth

Derek

 

[Derek Cohen (Perth Oz)]

The most important factor when cambering a BU blade is that you start with a 25 degree primary bevel.

I have a 30 degree cambered bevel on all my bevel up blades. I don't do micro bevels. This is how my dad taught me to do it and it works well for me so I see no need to change it.

Which BU plane and what do you use it for?

The cutting angle with a 30 degree bevel (and no secondary bevel) and a 12 degree bed is 42 degrees. This is lower than a BD Bailey design plane. Since the BU plane lacks the chipbreaker on a Bailey design to control tear out, and relies on a high cutting angle instead (generally between 50 - 60 degrees, the higher end being better for interlocked grain), I do not see how you could successfully use this bevel angle - unless you were either planing very straight grained wood, or using the blade in a block plane for end grain.

Are you referring to a BU plane or a BD plane? (I also use 30 degrees on BD planes).

Regards from Perth

Derek

 

[ED65]

..a while back I got myself a Veritas BU jointer and then got the BU Jack for an anniversary gift so want to get them working for me. I don't need heavy camber on the irons - just enough to prevent track marks and allow me to use effectively as a jointer on edges.

If that's all you need then may I suggest you simplify your task (and all future honings) and simply round the corners off?

Except at high skew angles rounding the corners works well to prevent track marks.

You can actually round them as described in older guides to prepping plane irons or relieve them in the way that Paul Sellers demonstrates, although the latter leaves you with ever so slightly less working width.

 

[Andy Kev.]

..a while back I got myself a Veritas BU jointer and then got the BU Jack for an anniversary gift so want to get them working for me. I don't need heavy camber on the irons - just enough to prevent track marks and allow me to use effectively as a jointer on edges.

If that's all you need then may I suggest you simplify your task (and all future honings) and simply round the corners off?

Except at high skew angles rounding the corners works well to prevent track marks.

You can actually round them as described in older guides to prepping plane irons or relieve them in the way that Paul Sellers demonstrates, although the latter leaves you with ever so slightly less working width.

That's what I've done with my Veritas BU Jack: just enough of the corners to eliminate the track marks and it works well.

 

[Derek Cohen (Perth Oz)]

I already have a Quangshen no5 that is used for knocking stock down but a while back I got myself a Veritas BU jointer and then got the BU Jack for an anniversary gift so want to get them working for me. I don't need heavy camber on the irons - just enough to prevent track marks and allow me to use effectively as a jointer on edges.

Petey, I have a 10" radius on my #5, as it is used for roughing out. The Veritas BU Jointer has a straight blade, since it is used for match planing as well as jointing individual edges. These are narrow, so you can get away without a camber. My LA Jack has a very fine cambered blade at 25 degrees, since it is used to plane across grain. It would have a straight blade if used to shoot.

Regardless of whether you want a fine or heavy camber, starting with a 25 degree primary bevel makes it easier. I'm not saying that you cannot do it another way, but those ways are not efficient methods. My preference is for BD planes, partly because the blades may be more easily honed freehand. I lack the patience for setting up a honing guide, but I do it for BU planes, because it is the best way. I learned that the hard way.

Rounding corners does not work as well as cambering - it relies on the plane blade being set perfectly parallel to the work, and limits how deep you can take a shaving.

Regards from Perth

Derek

 

[Derek Cohen (Perth Oz)]

Thanks for the reply, Beuker. I thought that you may have been referring to a block plane. That is a different matter to the high angle blades that the OP asked about (which is for a bench plane). Cambering 30 degrees is as easy BU or BD. Using 30 degrees is common place in a low angle block plane. I keep one with a 35 degree angle for chamfers.

Regards from Perth

Derek

 

[Petey83]

so spent a few hours on Sunday working on one of the 25 egree irons and ended up grinding a reasonable campre on it with the bench crinder before sharpening on the stones. The hollow grind made sharpening a lot easier and quicker and i am pretty happy with the results even though i lost half an inch of iron in the process and the camber is not dead even (i'm leaning).

I have decided to just easy the corners on my other BU irons and slowly apply camber with the veritas honing guides - this only gives the very slightes of camber but with the corners eased it works ok.

my original QS number 5 now has a heavily cambered iron and is more akin to a scrub plane now.

 

[Bedrock]

FWIW Axminster now sell a thin flexible diamond plate in grits from 400 up to 1000. Not at home at the moment, but I think they are about 4" X 9", and self adhesive. c. £18.50p.

I stuck mine to a flat piece of MDF and it works very well. I also like the larger surface. I seem to recall that the instructions (which I quickly threw away), talked about sticking it to a hollow base to achieve repeatable cambers.

Might be a cheap quiet solution.

Mike