hard chains

[Stubby]

43 minutes ago, Khriss said:

Doesn't seem to  ? air quenching is enuff. Tiny parts cool faster . Gentle with yr grinder is best, I use cutting grade discs as they softer / larger grit and remove more metal without cooking the tooth. The pink honing disc is harder / finer grit which IS best ( in the right hands ) k

If you can use a coolant whilst grinding even better . Engineering tool room slurry   made with water and soluble  oil is best .

[Rough Hewn]

If you can use a coolant whilst grinding even better . Engineering tool room slurry   made with water and soluble  oil is best .

What!!!!

How long to clean the chain after sharpening???

Oil and water emulsion with grinding filings in it won't do your bar any good.

If you just touch the tooth with a grinder until it sparks then lift 5mm

For half a second the air flow cools the tooth.

I get about 5-8 hits per slight worn tooth, or about 10-12 to change the top plate angle from 15-0 degrees.

Yes it takes a long time, but very good results.

I have to regularly sharpen 50"+ chains free hand so I do this a lot.

Nice shotgun btw stubs [emoji106]

[openspaceman]

2 hours ago, Khriss said:

Doesn't seem to  ? air quenching is enuff. Tiny parts cool faster . Gentle with yr grinder is best, I use cutting grade discs as they softer / larger grit and remove more metal without cooking the tooth. The pink honing disc is harder / finer grit which IS best ( in the right hands ) k

Yes what happens is the piece the grinding wheel touches gets heated to red heat but then the steel in the rest of the tooth rapidly quenches it so it chills quickly and the crystals thus formed are harder.

 

You can see this on the modern cheap (but good) hand saws where just the teeth look blue, they have been quickly passed through and induction process that has heated the sawtooth tip and then the surrounding air and steel behind the tip have rapidly cooled it again, hence the line of blue teeth.

[Stubby]

1 hour ago, Rough Hewn said:

What!!!!

How long to clean the chain after sharpening???

Oil and water emulsion with grinding filings in it won't do your bar any good.

If you just touch the tooth with a grinder until it sparks then lift 5mm

For half a second the air flow cools the tooth.

I get about 5-8 hits per slight worn tooth, or about 10-12 to change the top plate angle from 15-0 degrees.

Yes it takes a long time, but very good results.

I have to regularly sharpen 50"+ chains free hand so I do this a lot.

Nice shotgun btw stubs

What a wanker I turned out to be ! ?

[Rough Hewn]

What a wanker I turned out to be ! [emoji16]

Ahhhh, love you stubby [emoji106]

[difflock]

Gosh, ah actually went back and read the first part of this thread/post?.

An ye know whut?

Did I not read somewhere on here,  a good while ago mind, about cheapo chains from China, that were whilst "merely" carbon steel, were well overhard, like as hard as the carbon steel file usually used to sharpen such non-carbide saw chain.

And indeed, possibly/likely advertised or sold as "extra hard/stay sharp longer" aimed at the hobby market? 

Marcus

[Macpherson]

5 hours ago, Stere said:

Anyone try round dimond files

Hi, I use diamond files all the time, both hand and rotary...I'm an engineering fitter to trade and I've done a shit load of filing in my life, I've said it before... but saw chain is the softest cutting tool I use.....The harder the better imo, It takes a better edge that lasts longer and is more resistant to wear, simples.

 

So you can't sharpen it with a shitty file from your dealer... well, if I could sharpen any of my other cutting tools [ drills, router bits, saws, lathe tools, milling cutters, etc ] with a normal engineers metal file I'd consider them made of toffee and totally useless.

 

In any cutting situation, assuming that the power source works, the only important thing is the sharpness and angle of the cutting edge....And as Stubby said some kind of lube helps to maintain this....but each to their own

[Sam0207]

Thank you all for your help and advice, greatly appreciated!

[neiln]

I had a chain, i think it was one of the northern arb supplies/piranha chains, where just a couple of links had rakers that the file would not touch, far too hard, file just skated over.  chain was never on a grinder, hand filed until dead, never managed to take those 2 or 3 rakers down, the cutters filed ok though

Edited March 19, 2020 by neiln