WM Guide Arm

[Steve_M]

I was installing a couple of new guide rollers yesterday and decided it would be a good time to go through the complete adjustment.  Everything was looking good untill I noticed that there was had been a sllght grove cut in the last 2 inches of the guide arm.  It appears that my downset teeth have been rubbing. 

It looks like I only have between 1/16 (with arm all the way in) and 1/8 ( with arm all the way out) of space between the blade and the guide just before it enters the roller guide.

Should the guide arm be parallel to the blade???   When I have the arm all the way in I see a gap of at least 3/4 inch where the blade comes off the idle side wheel down to the 1/16 at the roller.

It looks to me like I need to tilt the arm assembly down and then adjust my blade deflection on the outside roller guide.

Thanks for any thoughts and advice.     

[slowzuki]

It should be parallel to the portion of the blade that is between the rollors, which should be parallel to the bunks.  The part of the blade between the guides and the bandwheels should not be parallel to the guide arm.

[Tom]

Whoa!
Is this on a Wood Mizer?
Are you sure you are using the right nomenclature?   The guide arm is the heavy piece of metal that carries the guide in and out.  It should be adjusted such that the distance of the blade to the bed doesn't change when you run the arm in and out.

There is a sheet metal shield that helps to protect hands from teeth (you shouldn't be there when it is running anyway) and it also helps to keep the sawdust that made the trip all the way to the Idle side from flying out into the open air.  If it is this piece of metal that has the scar, then it is a common malady.  when a blade breaks it can hit this metal.  If adjusted to close to the blade, harmonics may allow the blade to touch it.   It is mounted on an L shaped bracket that can be bent down a little and provide some clearance.

Don't start adjusting the guide arm unless you notice it is out of whack.  This is one instance of "Don't fix what ain't broke" is good advice for sure.   It's a difficult adjustment to get the guide arm parallel to the bed again, through it's entire travel length.     :P

[WH_Conley]

If a WM, go thru the manual COMPLETYLY, defelection should not change at all from all the open to closed.
I set mine just ike the manual says, then put the the down deflection on the rollers, that makes the clearance real close. I have grooves in mine, but I never really noticed them til I started sharpening my  own  blades and had breakage.
Close as you are talking, I don't think I would touch it.

[Steve_M]

Thank guys. 

I will not adjust the guide arm at this point.  Maybe I will slightly decrease my deflection to gain a little clearance.

Steve

[logwalker]

Do you have pictures or drawings of the area you refer to? I am having a tough time understanding your post. But would really like to. ;) LW

[Bibbyman]

Is there a possibility that the grove could have been made by a broken blade that came off and went crazy?  When I look inside the shielding on our LT40,  I can see a good many places where metal has been sawn away by run-away blades.   

[WeeksvilleWoodWorx]

Or maybe engaged the clutch without propery tensioning the blade? Usually after releasing the tension for a canned peas break? Not sure how that could happen, though  ;) ;D