Thread: The importance of even teeth?

Yes it makes a difference. I find the saw definitely want to cut on a curve if they are different, but will still cut. These days I am doing more hand sharpening, but at the end of the day, still do a proper sharpen with the grinder to even things up.

Thanks big guy
(I hope you know I'm only referencing the "dai" part of your name when I say that and not saying that you're a portly fellow - no idea what you look like - I just like using nicknames of nicknames )

I was always a bit haphazard in my sharpening and more often than not would just give the chains a quick swipe so I could go out and cut something quickly, always intending to fix them up later...but it never happened of course. The intention was always to file by hand with grinds at 1/3 and 2/3 of their life to get things back in line.

I'll give everything a good grind to balance the teeth up, redo the rakers and hopefully be back out cutting huntsmen into little pieces soon

He's a skinny little guy. But cute.

Originally Posted by RedShirtGuy

It looks like when I've been sharpening by hand that I've been doing it unevenly as all the teeth on one side of my chains are visibly shorter than on the other side. I guess it's come from using my dominant arm (left) on one side and using the weaker arm on the other.

If you set your rakers all to the same depth then cutters on one side being longer will definitely cause a problem because the longer cutters will have a higher raker angle (see picture) and so will bite more.

However cutter length alone is not the determining factor at to how much a cutter bites. Chainsaw chain is highly flexible and does not passively sit on the bar like a plane blade does in a plane.
When the cutter bites it lifts the cutter (and a section of chain) off the bar and the extent to which it first bites the wood is actually determined by the raker depth and the cutter hook. The cutter then bites and the raker resists in an alternately seesawing/rocking motion, until the chain tension gets too high and a chip is torn out - this is how chainsaw chain works.

What this means is if the rakers are set to constant angle instead of constant height or depth then the cutters being the same length is far less critical.
This only works if the lengths are sort of randomly distributed - if more cutters are longer on one side than the other then I do give them an extra swipe or two with the file to get them a bit shorter.

If you use something like a filo-o-plate to set your raker depth, it won't matter how sharpened down one set of cutters are, the raker height will be adjusted so that the tooth takes a proportionate amount of material. less tooth, more raker depth, more tooth less raker depth - this has the effect of keeping the chain running straight - check one out

I've only used the Husky filing plate - near enough I guess. Maybe it's the way I'm using it but I have to stop a few times a chain because my hands *REALLY* hurt from holding it, and it tends to rock and slip all over the place.

I had the same problem when sharpening my saw, I got a good tip from an old bloke one day, Once you sharpen one side of the chain( Dominant side) Turn the saw upside down, You are now sharpening the other side of the chain using the same hands, so you shouldn't have this issue.

cheers,
Jon

That right there is pure bloody gold!

Although, are chainies like lawnmowers and when you tip them over does the oil gets to places it shouldn't? I'm assuming it doesn't as (from my understanding) the oil reservoir is purely for the bar and separate from the oily 2str fuel/carby.

I sorted out the teeth and rakers on all my chains today . Gave them a good filin' with vernier calipers in hand, so they're all pretty much the same length now...give or take .Xmm or so.

Originally Posted by BobL

What this means is if the rakers are set to constant angle instead of constant height or depth then the cutters being the same length is far less critical...

Although raker depth more critical agreed, as the teeth are tapered, as the wear down there is less cutting face isn't there?

Originally Posted by dai sensei

Although raker depth more critical agreed, as the teeth are tapered, as the wear down there is less cutting face isn't there?

Correct, and wider or taller teeth will cut a slightly wider kerf. There is also a tendency for the bar to drift in the direction of the widest cut but provided variable length cutters are randomly distributed between LH and RH cutters they should even each other out.

I have a tendency to sharpen more on one side than the other and it definitely encourages the saw to head off in a curve. I attempt to counteract this by sharpening what I call the backhand side first (that is the left hand side of the chain when viewed from the motor). Then I do the RHS (which I suppose is the forehand ). This is because I can exert more pressure on the RHS (this is as a right hander) and I start on my weakest side before I tire a little.

This is not sufficient so I also give an extra stoke of the file on the LHS, but certainly not every sharpening. probably every other. I just gauge it by eye as to when I think the cutters on one side are becoming longer (umm that's really one side getting shorter ).

As the chain wears down through sharpening there is some loss of efficiency. An ex logger I know said he used to discard the chain shortly after the cutters had worn down to half length. Time for him was more valuable than chain. I sharpen until the first tooth falls off .

Regards
Paul

I have this same problem with hand saws & chainsaws. Only with the shape of the teeth it is more pronounced on hand saws.

To get over this I sharpen (Example) 3 strokes when using my dominant hand & 5 strokes when using my less dominant hand.
This works for me anyway & that's all that matters.

Give it a try , you've got nothing to lose.

HTH

Col

Like Bushmiller, I was taught by an old timer to always sharpen with your weak hand / side first. If you start with your good side you inevitably take off more than you do from the other