LumberJocks

Plane iron sharpening

  • Advertise with us

« back to Hand Tools forum

Forum topic by mbs posted 01-12-2013 04:21 PM 763 views 0 times favorited 7 replies Add to Favorites Watch
View mbs's profile

mbs

1476 posts in 1658 days


01-12-2013 04:21 PM

After reading some threads on sharpening I decided to tune up my #62 bevel-up and #5 bevel-down planes (not my favorite task). I want to see if I’m thinking about the functionality correctly.

I latched on to one of Don’s comments that the back is more important than the front. Yet, most of the time is spent on polishing the bevel side of the plane which makes sense on the bevel-up planes. But, in the bevel down configuration, why is it really important to have a mirror finish across most of the bevel (other than pride)? It’s really the back side that does the work. And, if you sharpen the bevel edge such that a fresh EDGE continues all the way through to the flat back side then that as good as it get from a functionality point of view, That’s really the strategy for people that like micro-bevels, right?

-- Sorry the reply is so long. I didn't have time to write a short reply.


7 replies so far

View Francisco Luna's profile

Francisco Luna

936 posts in 2111 days


#1 posted 01-12-2013 09:40 PM

any edge is the intersection of two faces at a certain angle, in most of the planes, 25 degrees. BOTH faces are important, and BOTH do the work at BOTH plane types, standard frog and bevel up planes.
Now. one of the faces “rest” evenly on the entire frog surface (bebel up planes), that’s why manufacturers lap them all the way down until mirror finish…........The “beveled” side only needs a sixteen of an inch in the same fininish, because it’s exposed. Standard planes blades do not need the entire back side lapped down, but just a section.

If you look with a microscope a blade that has been sharpened with a 1200 grit stone, you’ll notice a lot of steel fibers teared apart…..thats why sometimes the edge looks sharp enough, but once planing, it does’t last. A mirror finish is reached with a 8000 grit stone, and if you look again through the microscope, the steel iis way more “flat”, so the edge will last longer, of course the steel hardness also play a great part on all this.

-- Nature is my manifestation of God. I go to nature every day for inspiration in the day's work. I follow in building the principles which nature has used in its domain" Frank Lloyd Wright

View mbs's profile

mbs

1476 posts in 1658 days


#2 posted 01-12-2013 09:57 PM

Francisco, just curious, other than being the intersection of two planes, what work does the bevel do on the bevel down side iron?

I know what you mean by looking at the edges under a microscope. I did some work on improving machine cutters and reviewed edges under a SEM. At high power even an 8000 grit the edge looks like a the Colorado Rockies.

-- Sorry the reply is so long. I didn't have time to write a short reply.

View Francisco Luna's profile

Francisco Luna

936 posts in 2111 days


#3 posted 01-13-2013 01:06 AM

I think it is just making the edge to happen, since i is not resting on any surface.

I remember looking at a great book about sharpening, I found it at the local public library…...

-- Nature is my manifestation of God. I go to nature every day for inspiration in the day's work. I follow in building the principles which nature has used in its domain" Frank Lloyd Wright

View StumpyNubs's profile

StumpyNubs

6259 posts in 1518 days


#4 posted 01-13-2013 01:13 AM

Your are correct that when you say “if you sharpen the bevel edge such that a fresh EDGE continues all the way through to the flat back side then that as good as it get from a functionality point of view”. But the back has to be polished for that to work. Doesn’t matter if it’s a bevel up or a bevel down plane, the first thing you do is polish that back to a mirror finish. Then you should never have to do it again. Each time you sharpen the bevel in the future it will make a new plane between the bevel and that back side.

Take the time to polish the back once and you should be good for a long time.

-- It's the best woodworking show since the invention of wood... New episodes at: http://www.stumpynubs.com

View mbs's profile

mbs

1476 posts in 1658 days


#5 posted 01-13-2013 01:21 AM

I get decent shavings but i think they could be better. I’ve flattened the back but haven’t put a mirror finish on it. It’s around a 4000 finish. I think I will put a mirror finish on it and see it it’s any better.

-- Sorry the reply is so long. I didn't have time to write a short reply.

View davidroberts's profile

davidroberts

1003 posts in 2204 days


#6 posted 01-13-2013 02:50 AM

Bottom line – You want to finish the face side with the same level of polish as the bevel, or microbevel if you put one on. If you go to 6000 grit on the face and stop, then go to 6000 grit on the microbevel and stop. Any more work you do on one side and not the other is a waste. That is why you do not want to take the wire off of either side on a coarser stone than the one you finish with.

Honing with finer and finer grits will reduce (not eliminate) the ridges off the edge, bringing it closer to the theoretical infinite point – Rockies, to Smokeys, to Coastal Plain, so to speak. The quality of the steel not only determines how long the edge will hold, but just how close you can get to the infinite point.

-- God is great, wood is good. Let us thank Him for wood......and old hand tools.

View mbs's profile

mbs

1476 posts in 1658 days


#7 posted 01-14-2013 07:47 PM

I went down to mirror finish on the bevel side and the back. I had real good shavings before and now I have great shavings with a less effort. I can hear the difference on the #5. It’s a higher pitched sound as the iron passes over the wood. i don’t know if it’s because the iron is sharper or that I’m possibly taking a lighter cut, or both. Regardless, I like it.

I bought a Veritas Jointer Plane that should be arriving tomorrow. I’ll use the lessons learned on that plane too.

-- Sorry the reply is so long. I didn't have time to write a short reply.

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com

Latest Projects | Latest Blog Entries | Latest Forum Topics

GardenTenders.com :: gardening showcase