Bar problems

[SHOS]

Hi,

 

I bought an Alaskan Small Log Mill last year. Although I have managed to mill some very accurate boards (in terms of being of equal depth across the width of the board), I have always suffered from occasional 'wedge-shaped' boards (in my case the depth of the board getting narrower towards the end of the bar).

 

As an fairly inexperienced user, I first put this problem down to not tightening the pinch bolts enough. Now I put it down to the pinch bolts having slightly warped the other side of the bar and affecting the angle that it then projects at.

 

I was wondering if:

*anyone has some tips as to what might cause the wedge-shaped cuts

*how to avoid the pinch bolts affecting the bar

 

I thought the latter point may be caused by reattaching the mill to the bar too frequently.

 

Thoughts and help appreciated!

[Daniël Bos]

Most likely causes would be (in rough order)

bar rails not worn evenly.> check with set-square and dress if and when needed.

 

Chain not sharpened evenly. > measure, use a guide/ tool etc.

 

Bar rails splayed causing chain wobble. > check with a drive link, pinch in vice if needed, dress bar afterwards.

 

Pinch bolts.?

 

Bar bent.> straighten it if its a real good bar, Chuck it if not a sugi/cannon/equivalent.

[Rob D]

As above - you will get the bar wandering in the cut if any of these issues are there.

 

 

This is more accentuated with the small log mill rather than an Alaskan because the end of the bar is not clamped.

 

 

In the Alaskan you tend to get the bar sticking in the cut or the bar pulling down in the middle if things aren't quite right.

 

 

Bear in mind as well bars do not last forever - like a car tyre that can still perform as a tyre to support the car with canvas showing and no tread - a chainsaw bar will still cut through wood a long long way past it's prime.

 

 

It just won't do it well.

[Rob D]

But I'm going to be biased in this respect since I sell bars!

 

 

But it is true as well and milling is harder on a bar than normal cross cutting. Bar,chain and drive sprocket all need replacing when worn.

 

 

[SHOS]

Thanks.

I'll definitely look at replacing the bar.

Is there any way to avoid the small log mill's bolts which 'pinch' the bar causing a bulge on the other side of the bar? Do you think that's a sign of over-tightening or reattaching to many times?

[Daniël Bos]

If you can make a dent in a bar with a pinch bolt, you've either got a chocolate bar or you're more of a man then most, with less mechanical sympathy than Clarkson I'd say. :-)

[Rob D]

If you can make a dent in a bar with a pinch bolt, you've either got a chocolate bar or you're more of a man then most, with less mechanical sympathy than Clarkson I'd say. :-)

 

 

Haha!

 

But actually those pinch bolts are designed to put a small dent in the bar - in order to grip it where it is only clamped in one place.

 

 

[Daniël Bos]

A small dent to grip, but bulging on the other side?

[Rob D]

A small dent to grip, but bulging on the other side?

 

 

Hmmm yep the bulging on the other side should not be happening....

[SHOS]

you're more of a man then most

 

Consoled myself with this bit!

 

Bar is a pro-lite.