# Do bevel-up and -down planes work differently if the iron cutting-surface angles are the same?

 Forum topic by Brett posted 03-25-2011 10:39 PM 1334 views 0 times favorited 2 replies
 Brett660 posts in 2831 days 03-25-2011 10:39 PM Let’s say I have two planes, one bevel-down and one bevel-up. I also have a plane iron with a bevel angle of 25 degrees. Let’s assume that this plane iron could fit into either the bevel-down plane (at 45 degrees) or the bevel-up plane (at 20 degrees). In both cases, then, the angles of the the two surfaces that define the irons’ cutting edge are at 45 and 20 degrees to the sole of the plane. If all other things remain equal, will these two planes work equally well, or will the bevel-up or bevel-down position make a difference to the plane’s performance? A secondary question: does the back-side angle of the plane iron affect how it cuts, or is it mainly the front-side angle that matters? -- More tools, fewer machines.

## 2 replies so far

 Loren10477 posts in 3796 days #1 posted 03-26-2011 02:34 AM “A secondary question: does the back-side angle of the plane iron affect how it cuts, or is it mainly the front-side angle that matters?” Yeah – double bevel sharpening. When you raise the pitch of the topsideedge of the cutter above 45 degrees, the cut becomes progressively moreof a scrape. By back beveling a standard pitch bevel-down plane 5 to 10 degrees you effectively make the iron more suited to figured woods asit starts to scrape more. The method is also applicable to block planes and other bevel-up planes.By back-beveling the iron on a standard block plane (20 degree) you canmake it function more like a low-angle block. Almost all high-end bevelup planes made today seem to be low-angle (about 12 degrees), whichis about as low as you can go without making the plane mouth excessivelyfragile. richgreer4541 posts in 3223 days #2 posted 03-26-2011 03:58 AM This is one of those “feel issues”. The 2 planes should cut the same, but the will feel different in the hands of the user. The bevel up will have a lower center of gravity. I’m more accustomed to the bevel down and, for me, the bevel up does not feel quite right. OTOH, the versatility of the bevel up is quite appealing. -- Rich, Cedar Rapids, IA - I'm a woodworker. I don't create beauty, I reveal it.