Thread: Chainsaw sharpening, file or grinder?

Yes BobL, you are right, the rakers need to be set at their correct depth and with luck the combination tools I just bought will do that. This being the June long weekend on the mid-north coast the weather should start to clear late this afternoon and Monday it will be fine, by Tuesday the ground will be dry enough to walk on without getting too muddy and I can get back to cleaning up the mess after the fire so that rebuilding can commence. As the rakers wear down I can just round off the leading edges to reduce friction and reduce the chiseling effect a sharp, square edge would present to the timber being cut. As to optimising the raker depth to the timber being cut, well, that's going to be a problem for me as the saw has to cut all sorts of timber. At the moment it's mainly Aust. Hardwoods, Ironbark, Tallowood, Greygum, Turpentine etc. In another month or so it will be Paulownia with a bit of treated Pine mixed in for variety and to be honest I don't really have the confidence to keep increasing the depth of cut for each type of timber. What happens if I go too far of if the depths vary? At this stage I just need to clear up the mess and get on with rebuilding what we lost, perhaps then I can experiment a little.
Thanks for the advice, BobL. I may be in a position to do some experimenting next year.

Originally Posted by Old Hilly

As to optimising the raker depth to the timber being cut, well, that's going to be a problem for me as the saw has to cut all sorts of timber. At the moment it's mainly Aust. Hardwoods, Ironbark, Tallowood, Greygum, Turpentine etc. In another month or so it will be Paulownia with a bit of treated Pine mixed in for variety and to be honest I don't really have the confidence to keep increasing the depth of cut for each type of timber. What happens if I go too far of if the depths vary? .

The saw can stay pretty much constant as it's only the chain (and the drive sprocket)that needs to be varied.

In practice here is how I work.
I keep a couple of loops with higher rakers for harder/wider wood and just one with lower rakers for softer/narrower woods as I don't cut much of this.
It's not an exclusive operation , a chain that cuts harder/wider wood will still cut softer/narrower wood, just a bit slower.
If I know what I'm going to cut I will prep the saw beforehand with the sprocket and chain suited to the wood.
In the field I make a small adjustments e.g. if the wood is soft I'll be using the lower raker chain and if I sense the wood is extra soft I will knock a bit more off the rakers next time I touch up, i.e. after the next tank.
It depends what's and how much is being cut, the lower raker chain will easier cut hard wood if the wood is narrow enough so I won't swap chains/sprockets to do that if there's not much to cut.

I also have the added problem of having 10 saws with about twice that number of bars of different lengths, gauges and pitches.
In practice I use 4 bars mainly on two saws, a 24" and 25" on the 70cc saw, and a 42 and 60" on a 120cc saw. so I usually have ~8 chains and 4 sprockets with me when I go cutting. I carry a fairly extensive tool kit with me.

This is my chain case for the long chains
newcase2.jpg

I had bars hanging up everywhere in the shed until I made this box.
Boxopen2.jpg

Progress report, sort of. It's been raining here on the Mid North Coast but I made it back to the ruins with the Stihl filing gadgets and sharpened a chain that was new one tank of fuel ago. The flat file took a small amount of material off the rakers, just enough that you could see file marks on the top of the tooth. The ground was too soft and slippery to work safely so the saw stayed in the container awaiting some sunshine. I like the Stihl concept, it's a bit pricey but if it does the job and sharpens the chain properly then it's cheap.
And thank you BobL, for your contribution to the discussion, I am in awe of your knowledge and practical experience.

so how does the tooth profile change if filed for a rip cut?

Originally Posted by Sawdust Maker

so how does the tooth profile change if filed for a rip cut?

The primary change is with the top plate filing angle.
For cross cutting this angle is usually between 25 - 35º
For milling it's usually around 10º.
It will actually work at 0º but as it impossible to be sure if it's not slightly less than zero which could lead to a jammed chain its better to stay clearly on the positive side of zero.

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Just a brief update on the Sthil hand filing jig, it certainly seems to work. I have been giving the chain a quick sharpen on each tank of fuel and each time I sharpen there is a slight indication that material has been removed from the rakers. The chain is certainly cutting well, the saw is working moderately hard and the sawdust is mostly chips rather than powder so I am happy.

Originally Posted by Old Hilly

Just a brief update on the Sthil hand filing jig, it certainly seems to work. I have been giving the chain a quick sharpen on each tank of fuel and each time I sharpen there is a slight indication that material has been removed from the rakers. The chain is certainly cutting well, the saw is working moderately hard and the sawdust is mostly chips rather than powder so I am happy.

Its good to hear its working. If you want to, and have nothing better to do, you could post a side-on close up pic of one of your filed cutters (like I did on the previous page) and I will give you a diagnostic. I do this for a lot of folks on the Arborist site.

OTOH if you just want cut wood then go for it!.