Sharpening bench plane blades

[Travis Unruh]

Hi,

I'm a first time poster and I'm not sure if this is the correct forum.

I have recently gotten into woodworking and purchased a Stanley Bailey #4 plane to restore. I purchased a honing guide, a granite surface stone, and 120 grit sand paper to help me restore the proper angle to the plane blade (following the Video by Paul Sellers on plane restoration). As I have been grinding the blade, the top edge has taken on a slightly rounded shape. When I hold a square up to the blade, there is a 1mm gap on either side. I'm not sure if this is due to something I am doing, or if it is being caused by the tools/materials I am using (I'm assuming it's the former). Any recommendations or advice?

Thank you!

[Mike Kees]

Travis welcome to sawmill creek. Your question would be better addressed by the guys on the neander forum,they love sharpening questions. Good luck.

[Noah Magnuson]

Please provide some additional info, like how specifically you are sharpening, whether you are using the honing guide, which honing guide, was it square when you started ? etc. No wrong answers, just info to help diagnose what is going on.

[Jim Koepke]

Howdy Travis and welcome to the Creek.

Trying to trouble shoot your problem is a bit difficult without being there. If you are in the Portland, OR area I would be happy to try and get together to help. If not there may be a member near you willing to help.

One problem with abrasive sheets is they can move or swell causing problems like what you are experiencing. Adhesive backed sheets can help with this. Some have had better success by only using pull strokes on abrasive sheets.

Working the blade at an angle can also cause the type of problem you are having.

Good luck and let us know what works out for you.

jtk

[Matt Day]

And sometimes uneven pressure can cause the slight radius in the blade. Apply even pressure (not too hard) to the blad and make sure the wheel of the honing guide is solidly contacting the surface, and not rocking.

[Phil Mueller]

Travis, welcome!


Try using a magic marker to diagnose what's going on. Color over the entire bevel of the iron. Sand for a dozen strokes as you normally are doing.

If more marker is gone from the center than from the edges, perhaps the iron was heavily cambered to begin with and just needs more sanding. If the marker is more removed from the edges than the center, or the marker is removed evenly across the front of the iron and it remains rounded then you are likely either putting more pressure on the edges or the guide is tilting left/right while you sand.

Hope this makes sense.

[David Eisenhauer]

Many (most?) users intentionally put a slight camber or radius on the cutting end of the blade so as to eliminate the chance of "tracks" that can be left in the planed wood surface due to the square-edged corners of the blade digging in slightly as the plane is pushed across the surface. The guys above have all asked pertinent questions that can affect the blade end during sharpening, with the most pertinent being was the blade already slightly rounded before you started? As a new plane user (and sharpener), the radius could have been slight enough that you may never have noticed it was there without putting the square to the blade before sharpening. Radius is a good thing, but yeah, you need to know how to put it on there or not put it there if you don't want it. Leaning first on one extreme end of the blade and then the opposite end during sharpening with a single, centered wheel on the sharpening jig is a prime way to introduce the radius and you may have inadvertently done that. Or not.

[Travis Unruh]

Thank you everyone for the input.

The blade was in pretty bad shape to begin with. The curved edge came about after sharpening the blade until I had removed the original edge entirely.

It seems that it may have been the paper swelling as I pushed the blade forward. Taking jims advice, I adhered the paper to the surface stone and was able to get a straight and square top edge.

David - when adding the slight camber to the blade, does that create an arc across the entire blade edge? Or does it just remove the sharp corners?

[Tony Wilkins]

Thank you everyone for the input.

The blade was in pretty bad shape to begin with. The curved edge came about after sharpening the blade until I had removed the original edge entirely.

It seems that it may have been the paper swelling as I pushed the blade forward. Taking jims advice, I adhered the paper to the surface stone and was able to get a straight and square top edge.

David - when adding the slight camber to the blade, does that create an arc across the entire blade edge? Or does it just remove the sharp corners?

Nit David but regarding camber, though some just 'clip' the edge, I would think most camber across the entire blade.

[David Eisenhauer]

Check out some of David Charlesworth's (amongst others) sharpening advise videos/instructions for an exact method. Basically, after sharpening the square ended blade up fully, you then make five strokes concentrating your finger pressure on the back of the blade on one end of the blade, then three strokes with pressure somewhere between the center and end of the blade, two strokes at the center, three strokes at the next end-center midpoint and finally, five strokes at the opposite end. Or something similar. This should result in a radius edge. He also finishes it up (shows off) with a fancy figure eight, swirly motion to completely float out the whole sharpened end into a smooth radius. I believe this is a fairly common method whether a sharpening jig is used or not.

[Andrew Pitonyak]

Travis,

If you live near the middle of Ohio (Columbus, for example), we have a couple of people nearby that can help you....

The amount of camber depends on the intended use. If using as a smoother, you want a very small camber only (not that I usually camber my blades). If you want something to act like a scrub plane, then you want significant camber.

I know not very informative....

[Jim Koepke]

David - when adding the slight camber to the blade, does that create an arc across the entire blade edge? Or does it just remove the sharp corners?

Also not David, for a slight camber it doesn't really mater whether there is a 'true' arc across the entire blade or just a bit of metal removed at the edges. Here is my rambling discussion on sharpening and cambering a blade:

http://www.sawmillcreek.org/showthre...t-Finally-Came

My smoothers tend to work fine without a camber. That may be by the time the smoothers are in use it is only taking the thinest of shavings. If the shaving is 0.001" or less it will not leave much of a noticeable track at the edge of the blade.

As far as camber goes, a scrub plane should have the most. Some folks like to have various amounts of camber on all of their plane's blades. The amount is varied based upon the use of a particular plane. With a scrub plane having the most aggressive camber and jointers having less.

jtk

[Don Jarvie]

The back needs to be flat at least 1/2 inch from the tip. it's hard to explain but you should be able to see a uniform sheen. Then work the bevel. If the back isn't flat you'll never get the bevel razor sharp.