Chain sharpening

[Ollie]

I was milling a big thuja butt today and the chain seemed to be dulling really quickly. I'm sharpening using the granberg precision grinder which I've been using for a while and generally just tickling a bit off the chain to keep it sharp. The chain cuts well in hardwoods so I think I'm getting the angles right just can't work out why it was cutting so badly today. I did forget to take the burrs off the cutters after sharpening I've never really thought it makes much difference but I can't think of another reason for the chain going blunt as the wood was pretty clean. :what:

[wisewood]

Clutching at straws but have you taken the depth gauges down?

You could try a few strokes with a new file on the cutters, I find you get a better finish than just the precision grinder.

 

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[CJM]

If you don't remove the burrs it'll peel the chrome off ever so slightly resulting in a dull chain after a few cuts. Depth gauges is also a good shout

[Ollie]

Took the rakers down to correct depth. I'll try again and make sure I take the burrs off next time. It was painfully slow today and chain/bar getting hot cutting at full width with 36" b+c

[bobh]

I had this a while back, got a new granberg chain off of RobD and milled some ash in the morning all was well.

Went out in the afternoon to mill a few sticks on the local estate, was told they were Scots pine and had nothing but trouble, having to sharpen every cut at least. Tried removing the bark but it was still the same. In the end I pulled out of the job till I could work out what was wrong.

Used the same chain, sharpened exactly the same way, to mill a big burry elm last week and all was well. Came to the conclusion it was the timber, quite what it was in the timber I don't know but it certainly caused me to doubt my sharpening for a bit.

[agg221]

I have had this problem too, in my case with spruce and some sycamore for Se7entdevil. No idea why - both cut fine with the bandsaw; the chain was fine straight after on some oak and elm respectively.

 

Alec

[mrstumpy]

I had the same with the granberg precision grinder. Perhaps look at your depth gauges and only sharpen with a file. I only keep my grinder with the hope I may save a really blunt chain in the future.

[Ollie]

I did wonder if it was something to do with the bark I thought I was gonna rip through it fairly quick. I milled a thuja a few weeks ago and had no problem with it

[morten]

I have experienced similar trouble on an occasion, milling with an Alaskan mill.

It turned out that the bar clamps on the mill were not evenly tightened, causing the bar to be slightly tilted. I had to push very hard to make any progress at all, and was only producing very fine dust, and the bar/chain was getting very hot. Loosening the bar clamps, and re-tightening (checking that the bar was flat on the bar clamp solved the problem.

 

But it took about an hour before discovering the real cause of the problem.

[agrimog]

for some strange reason, a chain will blunt a lot quicker in soft woods than it does in hardwoods, something to do with the way the longer fibres tear, rather than shear during the cutting action. I found that an angle of between 5 and 7 degrees seems to last a bit longer on soft coniferous species, and down to almost 0 degrees on sitka gives a ready to use finish off the saw