Chain Grinding

[Philbert]

The problem with most grinders is that the chain stop isn't wide enough to hold both sides of the chain evenly to be able to hit every tooth in one revolution.

Look at the cheap Oregon stops... They are necked down at the tip.

The Tecomec/Oregon stops are designed to be adjusted side-to-side for R and L cutters. More of an issue when the cutter is well used.



Philbert

 

[Philbert]

I should say that I do not totally ignore the factory spec angles.
I got some Oregon Type 90 (3/8, low profile, narrow kerf) chain that spec'd a 4.5mm file (11/64") - which is a larger diameter than the 5/32" spec'd for Type 91 chain (3/8, low profile).
I tried it - it worked really well! They said that the cutters have different profiles.

Philbert

 

[ChoppyChoppy]

I think these tips of the stop all get ground down when the operator tries to sharpen chains that have almost no cutter left and should have been thrown away. The wheel is then almost on top of what's left of the cutter. That and the wheel is being allowed to drop too far down. Just my observation...

Not "tries" to sharpen, but actually does sharpen. It's worse on .404 harvester chain too.

 

[old guy]

If I were to use my grinder much I would agree with the 55 degree thing, it puts a better hook on the tooth.
I seem to have a better understanding of the 10 deg. down thing too, if you file a tooth at 30 deg. with the file level and then drop the file 10 deg. there is a gap at the outboard end of the top plate, moving the file back to close that gap while maintaining 10 deg. down you can keep the 30 top angle but will be cutting a thinner sharper side plate. my .02 worth.

John

 

[Philbert]

if you file a tooth at 30 deg. with the file level and then drop the file 10 deg. . . . you can keep the 30 top angle but will be cutting a thinner sharper side plate.

The compound angles get complex.

Philbert

 

[old guy]

It's really not that complex, while you're now probably holding the file at 40 deg., the down angle allows the top plate edge to roll over the file at a different angle maintaining the 30 deg. edge.

John

 

[Wood Doctor]

The Tecomec/Oregon stops are designed to be adjusted side-to-side for R and L cutters. More of an issue when the cutter is well used. View attachment 472585

Philbert

Yes, they are. Even the Oregon clones allow a side-to-side adjustment of the stops. That's especially useful when the cutters become small and the chain is thus almost ready for recycling. Many customers have told me, "Edwin, sharpen it if you can, but throw it away if it's a dead puppy. I'd rather just buy another loop from you."