sharpener help

[LeeB]

When I sharpen a blade is the whole gullet and back sopposed to be ground. I am only getting a face grind and a small tip of the back. the wheel lifts before it grinds the gullet. Called woodmizer and got hte right cam for the blades I'm using, but that didn't help. It does come a lot closer than the other cams I had though. What am I doing wrong. If I try to set the depth/back grind ot takes out the whole tooth. Not Good LeeB

[Tom]

LeeB
I'm assuming that you are using WM blades.  I have this same thing happen on my sharpener when I use Lenox Woodmaster C's.   Their teeth are quite tall, apparently, and it takes several sharpenings to get the tooth short enough to match the cam.

I have had this problem when the cam and blade match and it usually goes back to dressing the stone.  You can dress the stone thinner and it will allow the sharpener to get down into the gullet better.  Are you reaching the bottom of the tooth on your face grind?  That transition curve at the bottom of the tooth is important even if you aren't gumming out.

I didn't answer your question.  Must be "old-timers".  

It is important to dress the entire profile of the face, gullet and back of the tooth.  However, I usually don't on the first sharpening and maybe even the second when I have a situation like you described above.   I do a minimal face grind...just barely touch it.  I get enough of a back grind to sharpen the tip.

The biggest reason for a face grind that I can determine is to flatten it after setting the tooth.  Setting bends the tooth and causes the face to not be parallel to the direction of travel. A light face grind fixes that.  

I get most of my sharpening on the back grind.

Gumming the gullet is important because the technicians say that it gets rid of the microscopic cracks that begin in the gullet.  If you can't get the stone down in the gullet then I would say that a sharp blade is more important.  If you don't stress or over-use the blade between sharpenings then gumming probably isn't that important for a couple of sharpenings.  That's just a guess though.  I haven't suffered any ill effects from this that I am aware of.

[LeeB]

Tom, I am getting a full face grind or at least i think i am. the grinding wheel lifts before the blade starts to push forward. The wheel follows the profile real nice, just never touches it until it takes a small grind off the top of the back. About what you described. I ordered a cacm from Cooks for the lennox blades and a cam from WM for thier blades. same thing with both for both respective blades. I manage to get them plenty sharp enough, just not "mucking" out the gullet. Thanks for the reply. I'll keep on playing with it. LeeB

[BBTom]

The amount of "corner" that you take off the wheel on the right side (back grind) makes a big difference on the depth. Try playing around with your wheel profile.  You will get it.  I also agree with Tom, and don't worry about it if I don't get the whole gullet first time on a new blade.

[woodmills1]

my woodmizer sharpener has a screw to limit the downward travel of the wheel, if yours has one make sure it is not stopping the wheel from moving all the way down to the gullet.

[solidwoods]

Grind Angle set to match blade?
Bottom stop check?
Wheel not too small dia.?
Cam and blade tooth space same?

You can also set up with a new blade and alter the cam to match the blade perfectly .  It's easy and the changes that you make are minimal.  I mark the cam area that needs to be reduced, angle grinder (if allot has to be removed-gentle hand) smooth and feather with a file.

I have a Solidwoods cam profile that I use allot. It is right between WM and Timberwolf and loves wood fiber.

And yep you need to sharpen the whole profile.  Sharpening the tooth face also remakes a 90deg sharp corner on the entire face, which helps the cutting action.

Those of you that sharpen try this one.
Sharpen/set a blade.
Set to your favorite set for the blade/logs.
Make one cut with the blade (a cant works best) and check the set.
Now Add some set more set, a higher # , like .035, or add ten thousandths to your original set and do another cut/set check.

I've found on 1.25" thin blades- set up to about .025- hold the set pretty well,,increase the set .035 and allot of the set gets pushed out, also the blade seems to not make as much bf till dull.
I haven't tried this on a thick blade. The results would probably be different if it could take the extra set with out breaking teeth.


The reason I've tried this is some customers ask for more and more set.  I think over setting can stress the teeth and shorten it's life (kinda like Mountain Dew).
JIM

[LeeB]

haven't measured the rock. will have to try that. and maybe try tweeking the cam. thanks for all the help. LeeB