Veritas (and others) plane blade question

[Greg Parrish]

When looking at the alternate blades for my Veritas BU Jointer, and my recently acquired BU smoother, is the angle they reference referring to the primary angle of the blade, or is that the secondary bevel?

In other words, on the BU jointer, is the 50 degree blade really a 25 degree blade with the secondary bevel set at 50? Or is the primary bevel actually ground to 50? I can't find anything that actually clarifies on their website documentation and I don't want to make the wrong assumption.

Thanks.

Greg

[Rob Luter]

When I had a LV Low Angle Jack the blade grind angle referred to the primary bevel. I believe these two planes use the same blades. The 50 degree blade was ground at 50 degrees. It was great for reversing grain. A 25 degree blade with a 50 degree secondary would do the same thing and be quicker to sharpen That’s the setup I have now with my LN 62.

[Greg Parrish]

When I had a LV Low Angle Jack the blade grind angle referred to the primary bevel. The 50 degree blade was ground at 50 degrees. It was great for reversing grain. A 25 degree blade with a 50 degree secondary would do the same thing and be quicker to sharpen That’s the setup I have now with my LN 62.


Thanks Rob. That's what I wanted to confirm. Was planning to follow Derek Cohen's advice using a 25 deg primary bevel, but wanted to make sure I was interpreting correctly that they were advertising primary bevel. In this case, I would buy a 25 degree then and put my own 50 degree second bevel on. Didn't want to do this to my primary blade, which I have a 30 deg 2nd bevel on, but wanted to try Derek's approach for really tough grain. His info is found in this link.

http://inthewoodshop.com/WoodworkTechniques/TheSecretToCamberinBUPlaneBlades.html (http://inthewoodshop.com/WoodworkTechniques/TheSecretToCamberinBUPlaneBlades.html)

[Thomas Crawford]

Its the primary. I think they have an intermediate angle that bought (38?) and used that one to put a secondary 50 degree on. But the 25 is fine for that too.

[Derek Cohen]

All bench plane blades, whether BU or BD, need to have some camber. Smoothers have the least camber, but still require camber to avoid tracks. A BU smoother needs more camber than a BD smoother owing to the lower bed angle.

So try cambering a 50 degree bevel. Too much steel to remove. 38 degrees is almost as bad. Answer: stick to blades with a 25 degree primary bevel, and add the high secondary bevel to this. At the same time hone the camber. This will be relatively easy to do now as the amount of steel involved is small.

Regards from Perth

Derek