The Forestry Forum

General Forestry => Chainsaws => Topic started by: Woodhog on February 16, 2006, 05:10:50 PM

Title: Speed of Saw vs size of cuttings...
Post by: Woodhog on February 16, 2006, 05:10:50 PM
If a chainsaw is running to slow would it affect the size of the chips from the cutters or just the speed of the cut???

Thanks
Title: Re: Speed of Saw vs size of cuttings...
Post by: rebocardo on February 16, 2006, 06:56:28 PM
From watching other people, both. Though it looks more like sawdust then chips. Might be from a dull chain too.
Title: Re: Speed of Saw vs size of cuttings...
Post by: Ianab on February 16, 2006, 07:06:30 PM
Size of the chips is usually due to chain sharpness, but if the saw is running 'slow' for some reason it wont be developing full power, so it wont be able to drive the cutters properly, you will have to reduce the pressure on the cut / lift the saw to maintain rpm, and that will give finer chips and even slower cutting.
Chain speed wont have a huge effect, some saws rev at 8,000 rpm, some at 13,000, both cut fine if they are running properly, even though the chain speeds are different.

So if it's an older saw that just revs slower but still has good torque, then it may just cut a bit slower, but should pull out good chips. If it's a sick saw then all bets are off  ;)

Ian
Title: Re: Speed of Saw vs size of cuttings...
Post by: OLD_ JD on February 16, 2006, 08:11:16 PM
the rocker gauge will give you the chip size ......i think :P
Title: Re: Speed of Saw vs size of cuttings...
Post by: Al_Smith on February 16, 2006, 10:04:09 PM
Size and type of cutter have a great effect on chip size.An obvious difference can be seen between say 3/8" low profile and .404 chisel.

I have an old McCulloch 650 geardrive that has a 2 to 1 reduction.While the engine runs at around 9200 rpm,the chain speed is rather slow,by comparison.Due to the fact that it runs 1/2" chipper chain ,it will often pull a long chip ,in maple etc that is several inches long.Much like a wood plane.

I think it could be stated that as a general rule , the larger chains make larger chips .
Title: Re: Speed of Saw vs size of cuttings...
Post by: Deadwood on February 18, 2006, 02:13:43 PM
I think people getting cranked up about chain speeds and chip size when they really shouldn't. If you bring chainsawing down to its simplest form, what you are trying to do is make a cut from point a to point b in the shortest time.

You can do that in two ways. Knock down your rakers and really pull out a heavy chip, but slow down your chain's speed or...

You can take a lighter cut but keep your chain speed up and make more chips per second...

Logging is a matter of balance, from toppling trees to figuring out just how much to harvest on a given acre. Sharpening a chainsaw is the same thing. I use a Stihl chainsaw which tend to have more torque, but less rpm so I lean towards lower rakers and a heavier chip. If you run a Husky, you might lean towards a lighter chip and faster chain speeds as they turn up more than a Stihl.

Ultimately the "balance" you find is up to you. When you find that you have to file a new saw chain right out of the box, that's when you know you have found your sharpening preference and style.