Help w/ my WM band sharpener not putting in any hook angle. Augh!

[Kelvin]

Well i've been noticing a gradual decrease in my cutting speeds and been looking at my bands closer.  I think i have about a 0 degree cutting hook!  I don't understand why this is happening.  I recently put on a new wheel and dressed it properly.  I've set my motor head (i've got an old style woodmizer sharpener w/ small motor) to 9 degrees, why doesn't it come out with an angle?  I've read my manual and it says the lower left hand corner of the stone needs dressing, but i've dressed 1/2" off the stone and still won't put even the slightest hook into blade.  I've tried advancing the blade under the stone more and backing off the face grind, both ways and no luck.  What seems to be happening is that the blade is being pushed along before the stone comes all the way down and so i'm ending up with a totally perpendicular tooth.  If the blade stayed still when the stone came down, it would have to come in on an angle that the head was on.  There is no other way i can see why the tooth face wouldn't have any hook.  my teeth seem to be really quite small as well. (short)  I try to grind evenly from the face to the gullet to the back of the next tooth, w/ a little extra on the back grind as i've heard this is the way you want it.   Any ideas?  Help?  This is a new stone after i've been using an old one for too long, maybe 3 1/2" in dia.  Maybe i just can't get the hook back?  What do you guys think?  Maybe i'm overlooking something.  Thanks for any help!
Kelvin

[LeeB]

I think you found the cause already. The wheel is pushing the blade as it swings down. I had the same problem. Try taking a real light face grind. I can't remember if that helped or not. I have switched to a different brand sharpener. I cant't remember if there is any way to tighten up the clamps the blade slides through or not. Seems like there are some bolts to tighten up the springs that hold the movable side. Also make sure everything isn't all foulded up with residue from the sharpening. I'm sure somebody else will come along and give you better ideas than this.

[Fla._Deadheader]

Have you ever taken that clamp apart and cleaned it ???  Steel grindings will rust together and prevent the clamp from firmly gripping the blade. You would be surprised how much buildup there is.

[WH_Conley]

Too much grind on the left side of the stone, Improper spring tension (how tight is the blade in the clamp), too fast feed rate will not let the stone have time to cut, it will push the blade.

Probably need to touch the right side side of the blade just a touch after every blade or so. Improper stone profile will let the teeth get shorter (takes more from the back of the blade than the gullett).

[Tom]

I've mentioned this several times in the past and Deadheader is square on.

Your problem is a clamp that is not clamping the band.  Usually that comes from dirt (grindings) getting into the clamping surface and preventing the band from being held.  It could also be a mis-adjustment in the pins, but not likely.

Reach below the clamp and you will find a knurled plastic knob.  Turn it counter clockwise until it falls out of the clamp.  The two pieces of the clamp will come off of the sharpener.  You can then unscrew the spring tensioner and remove it .  This lets you separate the clamp into two pieces and clean it good.  Sometimes you even have to scrape the surfaces.  Sometime a wire brushing will do. 

While you are at it, clean off the buildup of grinding material behind the clamp, in the vicinity of the nut that adjusts rake.

When you replace the clamp, make sure that it is tight up against the pins on each side.  That insures that the blade is held directly below the grinding wheel.

That Wood Mizer sharpener is a fine tool.  I don't think you will find anything wrong with it.



some more:
The radius that you put on the left side of the wheel is to create the transition curve at the bottom of the face of the tooth as it goes into the gullet.  It hasn't much to do with the rake.  When you are grinding the tooth, the stone moves straight down and the profile at that point is mirroring the shape of the stone.   If your transistion curve is too squiare, then your stone is dressed too square. 

The cam doesn't come into play until the band begins to move and the gullet is being gummed out.  The height of the tooth and the steepness of the back grind is a combination of the cam and the shape of the right side of the grinding wheel.

[LeeB]

That's what I was trying to say :D

[Kelvin]

Thanks for the input guys.  I've been looking over older blades that i broke when they were fresh and i can see the old pattern.  This is a result of me using the same 6 blades over and over so as not to change the profile.  Once they get in a system they fit the stone well so i don't throw any new ones in till they all wear out.  THis is a case of boiling frogs slowly in a pot of water, apparently they don't jump out.  If you throw them in boiling water they try jump out.  I just kept making the profile worse and worse and never noticed.  I pull my bands quite early when they dull so as to make sharpening easier so they were probably sharpened a dozen times.  I believe it was too much face grind, but the stone wasn't to the right shape either. I don't think i will spend the time to bring them back around as the teeth are about 1/2 the height of my newer blades.  Its amazing how this could happen.  I will try take a picture of the two side by side, its pretty funny.  I can't believe they cut at all.  I'm sure it's zero degree hook and very short teeth.  maybe good for cast iron wood, like dry, dead white oak?  I don't know how they work at all.  Its nice to put a real band back on, and remember what they were suppose to do.  Sheeze!!!  Feel asleep at the wheel there.  I'll make sure and clean the clamp as well.  I tried getting flat metal down in there, but i do want to take apart and clean out.
Thanks all,
kelvin

[WH_Conley]

Just a little trick. When done sharpening, take a screwdriver and put it on the back half of the clamp and push a few times. Do the same thing when you turn it on again, with the water pump running. Be suprised how many times that yoy don't have to take the clamp apart to clean it

[Bodger]

One thing that will eventually come up is the little hardened pin in the push arm...the part that contacts the blade and makes move.  The blade can wear a groove in that pin over time (years) and it will cause the blade to snag every once in a while.  You can take a pair of needle nose and turn it 180degrees for another few years of service.  While we're on sharpening...on my older WM setter the little screw on end of the micrometer, the part that contacts the tip of the blade to read the amount of set, has come loose several times.  The symptom is erractic (is that the way you spell that?) readings.  When the setter starts acting goofy that is the first thing I check.

[woodmills1]

for the older sharpeners there is a clamp upgrade.  I got it and my old clamping problems are gone.

[backwoods sawyer]

on my older WM setter the little screw on end of the micrometer, the part that contacts the tip of the blade to read the amount of set, has come loose several times.  The symptom is erractic (is that the way you spell that?) readings.  When the setter starts acting goofy that is the first thing I check.

I have found that all the little screws on the gauge loosen up, but a little lock-tight will solve the problem.

Just a little trick. When done sharpening, take a screwdriver and put it on the back half of the clamp and push a few times. Do the same thing when you turn it on again, with the water pump running. Be suprised how many times that yoy don't have to take the clamp apart to clean it

This is a good habit to get into.


I have also found that sealing a large magnet out of a speaker in a good quality plastic bag and placing it in the tray under the grinding wheel makes for easier clean up.

I always thoroughly clean the grinder after each day of sharpening and store it with a light coat of oil.

I also oil my saws with a good coat of 90 weight after sharpening so they do not rust. This also allows the saw to start off with a protective coating on the wheel until the water spays on the saw. (I run metal wheels on the mill not rubber)

Note:
I use plenty of oil and grease on my mill as well, just as long as it will not contact the wood.
I find that most people have to much grease in there grease gun.