Chain Sharpening issue...driving me nuts!

[altair]

Hi guys, been having an issue whilst sharpening chains recently, was out before sharpening the 661 and GS650 and its driving me crazy!
First up I'm cutting Pine only, which is a relatively soft wood, even dry. I keep my chains pretty sharp, and the saws/chains/bars always get a good clean after each full days use.
Trees are clean, I avoid cutting too close to the ground too. generally chains last me quite a while, even though I'm not afraid to get stuck in when sharpening.
But lately (last year or do) sometimes when I'm hand filing the file just skips straight across the tooth without cutting, as though I'm using a damned nail to file with.
What the hell causes this? My files are either Oregon or Vallorbe (my fave), crappy Stihl files don't get a look in here..may as well file with a Banana.
This happens with brand new files too, in fact brand new or pretty worn, often they will skip straight over the tooth and not do a thing.
So what am I doing wrong? Or, what causes this? 661 has Stihl chain, GS650 has "Longer" brand (Chinese, but damned good chain which holds its edge well, respected brand in NZ with the guys I know).
Hopefully someone on here has a simple answer..when this happens I have to use a little Diamond bit on a 12V sharpener to do it..and I've always been a hand filing guy so would rather not use this sharpener.
To give you an idea of Pine wood here in NZ, and how soft it is, this video is of an MS660 I put together for a mate and this is it's maiden run, in Pine. (Saw has been tuned properly now). Crappy sound but its just my phone.



Thanks all.

 

[HarleyT]

Does this problem crop up after you have sharpened the chain with your 12volt grinder?

 

[HarleyT]

Can you put up some pics of your cutters?

 

[Andyshine77]

You could be overheating the teeth when you grind them. Stihl branded files work just fine for myself.

 

[altair]

Not a good pic..looks like it has no Gullet!

 

[altair]

Yeah I'm gentle with the diamond bit..don't think I'd be overheating them..I've had no joy with Stihl files, even on chains with their first sharpen..must be just something I'm doing wrong. As for doing it after they have been sharpened with the grinder no, it was happening before I bought that. Here in NZ things are expensive, it was over $120 for the 12v sharpener and one diamond bit..a pack of 3 Oregon stones costs $30! But i have the grinder for when I'm out all day and lazy..plus sharpen friends saws with it as well. I've been hand sharpening for many years, always get big chips and a saw that pulls itself through the wood. Hardest part I find is keeping angles the same both sides, and occasionally taking a raker too low..

 

[Andyshine77]

Not a good pic..looks like it has no Gullet!

Is this after grinding? To me it looks like the tooth doesn't have enough hook, and the top plate edge looks pretty dull. Can't really tell how the corner looks.

 

[pa firewood cutter]

I believe your teeth are hardened by grinding, I hand file a lot, (enough to have a jig to speed things up ) I will not sharpen chains that have been ground for that reason, not say your doing something wrong it’s just that from my experience grinding chains makes them hard.

 

[altair]

Is this after grinding? To me it looks like the tooth doesn't have enough hook, and the top plate edge looks pretty dull. Can't really tell how the corner looks.

No this was one that the file skipped across as I was trying to sharpen it, so did it later with the grinder. It does have hook but the photo does not show it. Its a 3/8 and I use 7/32 files which should be correct?

 

[altair]

I believe your teeth are hardened by grinding, I hand file a lot, (enough to have a jig to speed things up ) I will not sharpen chains that have been ground for that reason, not say your doing something wrong it’s just that from my experience grinding chains makes them hard.

Thanks, it does sound like it could be the grinder then, I wonder if the diamond bit heats more than the stones do?

 

[altair]

Actually come to think of it now I never use the grinder on the small saws..and they file just fine..maybe this damned grinder can be banished to a drawer somewhere....

 

[Andyshine77]

No this was one that the file skipped across as I was trying to sharpen it, so did it later with the grinder. It does have hook but the photo does not show it. Its a 3/8 and I use 7/32 files which should be correct?

Ok it looks like it was ground with one of those little rotary stones. I also think the teeth are bring hardened from grinding.

 

[pa firewood cutter]

I believe the grinder to be the problem, try pferd files, made in Europe, very high quality and last a long time. To me it’s hard to beat a good hand filed chain.

 

[Andyshine77]

No this was one that the file skipped across as I was trying to sharpen it, so did it later with the grinder. It does have hook but the photo does not show it. Its a 3/8 and I use 7/32 files which should be correct?

Try a Stihl 13/64 file it's a hair smaller. This makes it a little easier to get under the tooth, this will give it more hook, it also makes filing a bit easier too. Don't worry about getting the top plate angles on each side perfect for now.

 

[altair]

Ok it looks like it was ground with one of those little rotary stones. I also think the teeth are bring hardened from grinding.

Probably the squirt of brakeclean to wash the crud off so i could get a pic...yeah I'm thinking grinder now. Maybe I'll have to use it the rest of this chains life, and then file only. Out of interest what size file do you use for a 3/8 chain? Looking on the net there are two sizes, maybe I could try the other size and see, but the 7/32 usually gets the point sharp, sharp enough to cut me easily when I put the bar cover on and slip..

 

[altair]

Try a Stihl 13/64 file it's a hair smaller. This makes it a little easier to get under the tooth, this will give it more hook, it also makes filing a bit easier too. Don't worry about getting the top plate angles on each side perfect for now.

Answered my question, thanks

 

[jackjcc]

I’ve had teeth harden like that and rakers too. I work with monkeys who forces their way through wood with dull chains. But even when the teeth have harden I just put a little more pressure and go much slower across the tooth. One pass usually breaks through the hard top layer and then it files as normal. So give that a try next time round and see how it flies.

Edit for spelling.


Sent from my iPhone using Tapatalk

 

[altair]

I believe the grinder to be the problem, try pferd files, made in Europe, very high quality and last a long time. To me it’s hard to beat a good hand filed chain.

I agree, something about a hand filed chain, maybe I'm behind the times but my chains seem to last a little longer than some mates who use the electric chain sharpeners, don't seem to stay sharp any longer either..and they don't get to enjoy the painful cuts on their fingers either from a hand sharpened chain!

 

[altair]

I’ve had teeth harden like that and rakers too. I work with monkeys who forces their way through wood with dull chains. But even when the teeth have harden I just put a little more pressure and go much slower across the tooth. One pass usually breaks through the hard top layer and then it files as normal. So give that a try next time round and see how it flies.

Edit for spelling.


Sent from my iPhone using Tapatalk

thanks for that, yep no need to push so damned hard..these are the same type of people that rev the saw when its running out of gas...like its magically going to refuel......

 

[Andyshine77]

I agree, something about a hand filed chain, maybe I'm behind the times but my chains seem to last a little longer than some mates who use the electric chain sharpeners, don't seem to stay sharp any longer either..and they don't get to enjoy the painful cuts on their fingers either from a hand sharpened chain!

A lot of it has to do with setup, if the grinder isn't setup right the chains will have all sorts of issues. That said unless you have a square grinder, hand filling is where it's at.