When I bring the grinding wheel down

[millbilly]

I've hand filed for over 35 years and Im sick of sharpening chains that employees dull. I found an oregon sharpener on craigs list with a stand and looked new for $50 bucks and had to buy.

Ive experimented with angles and have found what works best, I personally think the scales on the machine might be off, 54 degrees on there scale gives a much better edge instead as the suggested 60 degrees.

This is my question should I lower the grinding wheel slowly or hit it rather sharply? The reason I ask is that I don't seem to blue the chain as often if I hit it quick and firm.

What are your guys suggestion?

 

[Philbert]

Grinding wheels are brittle. Chain cutters are hard. So I would not recommend bringing them in contact quickly or sharply.

The cutters get blued by heat, which is a function of contact time. If you hold the grinding wheel in contact with the cutter for an extended period, you will blue the tooth. Same thing if you try to hog off a bunch of metal at once.

I use a series of short, light taps to reduce contact time. Think Morse Code - all 'dots', no 'dashes'. If I have to remove a lot of metal, I may do it in a couple of passes around the loop.

Larger diameter wheels help to dissipate the heat: 8-3/16" wheels are better than 5-3/4", 5-3/4" are better than the smaller wheels (4-1/8").

The type of grinding wheel also makes a difference. We usually don't have a lot of choices for chain saw grinders, compared to wheels used on bench grinders, but I would stay away from the cheap wheels. I buy the Molemab wheels sold by Baileys, which some people say is softer (heat up less, but get used up faster) than the Oregon wheels. Several guys on A.S. use the coated (ABN or CBN) grinding wheels, which they report to heat up and burn the cutters much less, but are quite a bit more expensive.

Philbert