How to keep steel temper while sharpening?

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City Slicker

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I've read many posts on using a chain grinder and have considered buying the Maxx from Bailey's.

It seems like whenever my saw dealer sharpens a chain for me it comes back with blued teeth.

How do ya prevent losing the temper while sharpening?


One tree service guy told me, he does'nt care because he's making $800-1500 per job and can afford to buy a roll of chain.
 
I've read many posts on using a chain grinder and have considered buying the Maxx from Bailey's.

It seems like whenever my saw dealer sharpens a chain for me it comes back with blued teeth.

How do ya prevent losing the temper while sharpening?


One tree service guy told me, he does'nt care because he's making $800-1500 per job and can afford to buy a roll of chain.

You don't get blued teeth if you do repetitive short grinding intervals so the teeth have time to cool down again. Further if you do correct adjustments before grinding so you don't take away to much of the tooth.

Sounds like your dealer is just being a little liberal in the measurements as to how much should I take away so he comes and buys a new chain in the shortest amount of time.

No bluing with the file though and really easy to learn. There are many fileguides on the market.

7
 
?

Do ya tap the tooth with the grinder and move to the next tooth until all are sharpened evenly on that side?
 
if you take a little at a time with a grinder or tap on the tooth, you will keep it cool. the dealer is just impatient.

That's the key. The dealer is gouging out way too much material. You want too just barely skim the tooth or like MR said hone it. When I'm setting up my grinder, I set it to move past the top plate (into the gullet) set the depth, and then turn the tooth in till it just starts too throw a spark. The rest of the teeth on that side will then be skimmed. Reset when doing the other sides. :cheers:
 
I've read many posts on using a chain grinder and have considered buying the Maxx from Bailey's.

It seems like whenever my saw dealer sharpens a chain for me it comes back with blued teeth.

How do ya prevent losing the temper while sharpening?


One tree service guy told me, he does'nt care because he's making $800-1500 per job and can afford to buy a roll of chain.

You probably don't end up with softer teeth but with much harder teeth. Saw chain saw when heated seems to air harden to the point where I can barely hand file it the next time. Use a grinding compound and a very light touch. I still prefer hand filing.
 
A mag lite - like in the style below is a handy tool to have around.
It will greatly help in seeing any of the color changes going on in the tooth, and with a slight side pressure or adjustment - aid in feathering/chasing any color out.
Also if you pay attention to the angles-- after the first slight tap to the tooth, in will help to make you a better hand filer quicker.

http://cgi.ebay.com/CRAFT-SWING-ARM...oryZ3099QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
 
You probably don't end up with softer teeth but with much harder teeth. Saw chain saw when heated seems to air harden to the point where I can barely hand file it the next time. Use a grinding compound and a very light touch. I still prefer hand filing.


I could've swarn the opposite...but I only gave the shop $10 for 2 chains ONCE and was pretty new to hand filing back then.


Either way it really jerks my chain (yep, I'm corny) knowing they didn't want to take an extra 3 minutes when it has to work out to well over $30/hr to sharpen chains at $5 bucks a pop. I've never used a grinder but surely it takes 10minutes or less? Heck, it takes me less than 10 minutes for my 24" by hand when I'm "bored" and I'm being extra careful/picky/deliberate.

If it's less than 5 mins. its up to $60/hr to keep $10/hr help busy.
 
You probably don't end up with softer teeth but with much harder teeth. Saw chain saw when heated seems to air harden to the point where I can barely hand file it the next time. Use a grinding compound and a very light touch. I still prefer hand filing.

That's interesting because heating carbon steels to a blue colour typically knocks between 5 and 10 Rc Hardness points off their full hardeness. The steel in chain is typically around Rc58 - 59 and should drop to 51-52 when blued. Fortunately in most chain grinding situations this happens so quickly the whole cutter is not affected and a few sharpenings later the harder stuff is able to be accessed. The quicker and the more is ground off in one grinder stroke the more of the cutter will be affected.
 
You probably don't end up with softer teeth but with much harder teeth. Saw chain saw when heated seems to air harden to the point where I can barely hand file it the next time. Use a grinding compound and a very light touch. I still prefer hand filing.

I agree 100% If you get them too hot they are hard as :censored:!! I just take a little at a time and use a file when ever I can!
 
You probably don't end up with softer teeth but with much harder teeth. Saw chain saw when heated seems to air harden to the point where I can barely hand file it the next time. Use a grinding compound and a very light touch. I still prefer hand filing.

I like your term 'air harden' :cheers:
As we know that heat and time draws back the temper or hardness. Hot steel can take on the nitrogen in the air and give us an extremely hard (harder then files) cutter!

Stands to reason, because we do find that once though the 'hard spot, it files easier then before it was changed from the factory.
 
I thought it was the chrome on a tooth which did the cutting and the steel just directed the cut material at an optimum angle for shearing and removal.
 
I thought it was the chrome on a tooth which did the cutting and the steel just directed the cut material at an optimum angle for shearing and removal.

There are a lot of ideas to this....

Ever notice that a chain dose not have to hit much in the way of dirty bark or anything and its finely chipped away right at the business edge?

If the steel backing the chrome were not hard enough, or did not resist ware well enough, just ramping the chips away would leave to steep an angle on the chrome left on the cutter.

We know that by how far we need to dress the cutters sometime to bring it all back to sharp.

The chain needs both
 
Steel grinding and sharpening

Has any one tried diamond wheels on their chain grinders? Here is a link: Diamond wheels

As you know, a dull chain creates heat and takes longer to cut. A sharper wheel should cut faster and cooler.

You cannot use diamond to sharpen steel.. you need to use CBN. Diamond is for carbide. The carbon from the steel messes with the diamond structure and destroys it.

yes, CBN wheels work great.
 
:confused:

I use diamond impregnated stones/hones (DMT) to sharpen my knives all the time. Some hit 62rHc!!!

Although it IS the softer metals that give the stones fit because the softer steel "gums up" too much...a simple scrub with water and a toothbrush clean right out and it's ready to go.

Diamonds give a more uniform surface so that you can actually "get away" with using a slightly coarser grit. (This sounds stupid...but it's conventional wisdom on a few boards I use to visit. Something about how the diamond "crystals" themselves are more consistent and you don't have those pesky outside-of-the-average-size particles to contend with.)

Coarser grits generate less heat than finer grits.

Diamond wheels, if they are appropriately made of a slightly coarser grit, would run cooler.

If the diamond wheels are no good for regular chains (and certainly wouldn't know since I don't even own a grinder) it is because of the manufacturer/bonding process and material...not because they are diamonds.
 
I know only enough to be dangerous, so...

Is the concern with using diamonds to sharpen steel only a problem at the high speeds of a grinding wheel? There are plenty of diamond sharpening stones for steel wood working tools, but they are for hand sharpening speeds. Maybe that is the difference?

I'd really like to know more about the metalurgy of a chain saw chain. So...

When a chains is "rocked out", and the cutters are hard to sharpen, is it because the cutting edge becomes "cold work hardened"? I hear this is done with some wood working tools to enhance the hardness of the cutting edge.

What kind of steel is used in chain saw chain? A2 steel is used in high end wood working tools - very long lasting edges, harder to sharpen, but not quite the finest edge possible. A series steels harden by heating and cooling in Air (twice if memory serves).

O1 steel is heated, then cooled in Oil to harden it. W1 Steel is heated and cooled in Water to harden it. O, W and High Carbon series steels are tempered by heating to 450 degrees (or so depending on the level of tempering desired) and cooling slowly in air.

I could see a chain tooth hardening if it is an A series steel and over heated with a grinder, but only getting softer if it is another series steel.

So, is there a metalurgist amongst us that can set us straight about what is really happening, and what sort of steel we have on our chains?

Thanks
 
You cannot use diamond to sharpen steel.. you need to use CBN. Diamond is for carbide. The carbon from the steel messes with the diamond structure and destroys it. yes, CBN wheels work great.

That's really interesting. I knew I would have to spend big bucks for a diamond wheel to sharpen carbide, but it never occurred to me that it wouldn't work on 'mortal' chains.

M.R. said:
Or: Think of it like doing jumping jacks and being lite on your feet.

The old Boy Scout in me thinks of it more as Morse Code; only send 'dits'; never send 'dahs'. Use a light touch. Might take 3 or 4 taps to take a tooth to the gullet. If it needs more taken off, I do the whole side, then reset and do it again. If you see bluing (happens right away), you know you are being too aggressive and need to lighten up.

Would like to try one of those CBN wheels sometime. But the ones that came with my Oregon grinder will probably outlast me!

Also important to keep the cutters on both sides the same length - harder to do when you have to take a lot off.

Philbert
 
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Yes, it' the heat that take out the diamond when used on carbon Steel. It's not for Chainsaw chain grinding.... ABN/CBN is. You "could" use diamond but it would have to be done very slowly... There is a lot of hand powered solution for knives, chisels etc. I have several.

I HIDE my diamond tool grinder wheels so I (or a helper...) don't use them on HSS tooling. it can be ruined in seconds. The CBN wheel is permanently mounted, but I still need to be careful to not use it on Carbide.

To help with the burning/burring of chains when using stone wheels, use "cool grind" and "peck"... We don't use stone wheels any more... just CBN.
 
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