this from leevalley.com. it was a pop up window so I couldn't give you
the exact link:
"
Sharpening the scraping blade is the most critical and difficult part of
learning to use a scraping plane. Understanding how a scraper cuts (see
above) and knowing what a properly burnished cutting edge looks and
feels like are the key concerns when learning how to sharpen the blade.
The bevel angle on the blade is ground at 45, rather than square as
found on card (cabinet) scrapers. This makes it easy to burnish or
deform the metal of the bevel into a relatively aggressive burr or hook.
The burnishing angle should be about 15. An angle of 20 or more will
result in too much scraping and not enough cutting (producing dust, not
shavings). The higher angle also increases the likelihood of blade
chatter. Smaller angles (closer to horizontal) may not cut at all as no
cutting edge is introduced to the wood, or there may be no relief angle
and the blade will just slide along the surface of the workpiece.
Step 1 Preparation: This step is not necessary with a new blade. Before
you start honing, the blade should be shaped to maintain a straight
cutting edge and a 45 bevel. Hold the blade in a vise and use a 6" or 8"
******* cut mill file to prepare the blade. Check the bevel periodically
with a straightedge and a protractor (or sliding bevel set to 45) as you
work. The Veritas Jointer/Edger (05M07.01) is ideal for this process. A
bench-top belt sander with an 80x or 120x abrasive belt may also be used
for this step.
Step 2 Honing: Start with an 800x or 1000x stone to remove the marks
from filing. Either an oil stone or water stone is suitable. Hold the
blade as shown in Figure 3 with the bevel flat against the stone. Stroke
it back and forth, covering the whole stone. Check the bevel often to
evaluate your progress. Continue until all file marks are gone. As shown
in Figure 4, lap the face of the blade near the cutting edge to achieve
the same finish as on the bevel. A sharp edge can only be achieved by
creating two intersecting surfaces honed to the same degree. Using the
same technique, transfer to a 4000x water stone or hard Arkansas oil
stone to finish honing. The Veritas Power Sharpener or a bench-top belt
sander with 320x (40) followed by 1200x (9) abrasive will provide the
same results a bit faster.
Figure 3: Honing.
Figure 4: Lapping.
When sharpening a thick blade, we recommend that you round the corners
of the blade to ensure they do not leave corner digs in the workpiece.
(You may also do so on a thin blade, but it is unnecessary if you are
going to bow the blade; see Bow Adjustment below). This is best
accomplished by creating a small round at each end of the cutting edge
as shown in Figure 5 when first preparing the bevel with a file or belt
sander. Work the rounded corners as well as the cutting edge at each
successive stage of honing.
Figure 5: Rounding the corners of the blade.
Step 3 Burnishing: With the blade held firmly in a vise, use a burnisher
(the Veritas Tri-Burnisher 05K32.01 is well suited) to create a hook as
shown in Figure 6. Use three or four even firm strokes across the entire
edge of the blade at the same angle as the bevel. Raise the burnisher
handle slightly and take three or four more strokes. Finish by taking
three or four strokes with the burnisher 15 from horizontal as shown in
Figure 6. The first few times you do this, sight against a reference
tool such as a sliding bevel or engineers protractor set to the desired
angle.
Note: Before burnishing, touch your fingertip to the side of your nose
or behind your ear (two natural oil sources) and transfer that minute
amount of oil to the blade. It reduces friction and avoids galling.
Toothed Blade Note: Sharpen and hone only the 45 bevel. DO NOT hone the
face of the toothed blade, or you will damage the sharp points that
actually do the cutting.
Figure 6: Burnishing.
Blade Adjustment
With the blade prepared you are now ready to set up the plane. A blade
burnished with a 15 angle will require setting the adjustable frog to
about 5 forward of vertical using the frog adjustment wheels (see Figure
7). However, if your burnishing technique produces an angle other than
15, you will have to determine the ideal frog setting. Use the scraping
plane blade like a hand scraper to find the angle that produces the
smoothest scraping action. Set the frog angle to approximately the same
angle you established with hand scraping. Ensure that the blade bow
thumbscrew is backed off such that it does not protrude beyond the frog
face. Set the scraping plane on a smooth, flat and clean work surface.
Insert the blade with the bevel facing the rear of the plane and the
cutting edge resting on the work surface. Lightly hold the blade in
place against the frog and tighten the lever cap knob (a quarter turn
should be ample do not overtighten) to secure the blade. The blade will
now be flush with the sole.
To advance the blade, pick up the plane and pivot the frog forward 1/2
or so. Just loosening the rear adjustment wheel and retightening the
front wheel may provide enough movement. As the blade pivots forward,
the cutting edge drops below the sole. Another technique you can use to
set the initial blade projection is to place a single sheet of paper
under the toe of the plane and set the cutting edge of the blade so that
it is just resting on the work surface. You should not have to adjust
the frog forward if you use this technique. Either way, the scraping
plane is now ready for use. Take a few quick test cuts and fine tune the
cut as required.
As the hook on the blade wears, you can continue to pivot the blade
forward to re-establish the cutting action. Again, a shift of only 1/2
or so may be all that is required. When making larger changes to the
blade angle, be sure to reset the blade flush with the bottom to avoid
moving the cutting edge too far below the sole of the plane. You may
continue to adjust the blade forward to about 25 or so. At this point,
if the plane is no longer producing shavings, the blade must be
resharpened and the frog adjusted back to the 5 starting point. "
I think the 600 grit is WAAAY to low a grit. You might have to adjust
some of the parameters for use with a Stanley, but I found that if I
deviate a few degrees from the instructions I get a lot of chatter.
Dave
B_Lerner wrote:
I recently acquired a Stanley #12. To make a long story short, I
proceeded to butcher the scraper edge, and will need to burnish a new
burr from scratch.
Here's what I THINK I should do (via google and books). Please let me
know where I've gone astray.
1. Flatten the back side w/ sand paper, from 60 - 600 grit.
[There currently is no burr.]
2. Sharpen the bevel side, as above, w/a homemade jig at 45 degrees.
[How sharp? Scary sharp like a plane iron?]
3. Lay the scraper blade flat, burnish the back side with a piece of
round tool steel (I'll use the side of a hole punch).
4. Put the blade in a vise and turn the burr with progressively
increasing angles to about 75 degrees.
[How much burr should I expect when I'm done? 1/64"? 1/16"?]
When the scraper goes dull, do I need to repear all of these steps
(assuming they're correct), or is there a way to resharpen the edge once
or twice before the full-blown re-working?
Thanks for any and all help!
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