The function of pitch

[Bolt]

But the gear ratio would not support this, unless you were purely working on soft woods were the tolerances are greater.

 

I used to run husky 254 on 3/8 pitch but i was working in Corsican / lodge-pole mix however try the same set up on a beech or ash or similar, even a knotty pine could cause problems. Simply buying a 262 would have been a better option.

 

Valid points.

 

But the 254 was using a chain designed for saws from 50 -something CC to oVer 90cc. Its right at the lower limit for that design of chain.

 

As I see it, If 'they' can design a 3/8" pitch chain for a 35cc saw, and a 3/8" pitch chain for a saws between 55cc to 90cc, why not a 3/8" pitch chain (made of all specially designed components) for, say, a 49cc saw.

 

What is so world shatteringly special about 39cc to 55cc?

[High Scale]

Pitch & Gauge Explained

[Bolt]

Pitch & Gauge Explained

 

yes, but it doesn't explain why. Why does it HAVE to be .325?

[3dogs]

Valid points.

 

But the 254 was using a chain designed for saws from 50 -something CC to oVer 90cc. Its right at the lower limit for that design of chain.

 

As I see it, If 'they' can design a 3/8" pitch chain for a 35cc saw, and a 3/8" pitch chain for a saws between 55cc to 90cc, why not a 3/8" pitch chain (made of all specially designed components) for, say, a 49cc saw.

 

What is so world shatteringly special about 39cc to 55cc?

 

 

Its not a case of designing a new 3/8" chain as theres nothing to change 3/8 is 3/8 the only way a 3/8 chain would run on 39 - 55 cc saws would be re- gear the sprocets to suit a 3/8 chain this would be unsuitable for the power output of such saws.

 

What is so world shatteringly special about any cc saw they all have a place. I certainly would'nt want to use the 441 to cut christmas trees all day as i would,nt want to use the 346 to fell large trees:thumbup:

[rowan lee]

thanks to all who have replied. An interesting picture emerging here.

Thought it was a silly question, but cheers Mesterh, would be good to get the definitive answer alright.

 

Interesting points with regards to gear ratio's, general strenght and duribility, and the theory from ben lightfoot.

[Bundle 2]

Nothing to do with gearing...its all relative to the system anyway being a closed loop I reckon.

My theory is this.......

The rivets are larger to allow for increased strength. This could be achieved by increasing guage but we dont want to cut a wide hole, we wanna cut down. Guage is not then the first choice for strength in this application. The rivet diameters are increased so as to improve tensile strength. This is a feature of the design. It requires a corresponding increase in pitch. Simples!

 

Ive never actually measured rivet dimensions on cutting chain. I know motorcycle chain works this way. I also know the pitch of the sprockets must match...hence my assertion that gearing is not an issue of pitch, at least, not in of itself. But one of diameter (OD) of the sprocket. We count this in number of teeth because we can assume a given pitch.....

Here's a little something to crash your grey matter with when you get a spare moment!

Some may find it interesting......?

 

Gearing Commander: Motorcycle Gear Ratio Calculator for Sprockets RPM Speed Chain

[High Scale]

Function of chain pitch?

[TimberCutterDartmoor]

Function of chain pitch?

 

A good read that.

[Bolt]

Function of chain pitch?

 

It's strange how people don't consider things.

 

On that forum, posters instantly state that a low profile 3/8 would be no good on a ms441, and that a 'full' profile would be no good on a 338xp. Well we all think that.

 

.325 is handy for those saws not suitable for either. Well this is also true.

 

 

 

I just wonder why an 'intremediate' profile 3/8 chain hewasn't developed for saws in the a 40 to 55cc range.

[Bundle 2]

It's strange how people don't consider things.

 

On that forum, posters instantly state that a low profile 3/8 would be no good on a ms441, and that a 'full' profile would be no good on a 338xp. Well we all think that.

 

.325 is handy for those saws not suitable for either. Well this is also true.

 

 

 

I just wonder why an 'intremediate' profile 3/8 chain hewasn't developed for saws in the a 40 to 55cc range.

 

Cos its a matter of gearing frankly...And everytime you alter the length of your bar....it must necessarily run past the wood (chips per second!) slower. ( unless you alter power output by changing the saw perhaps) So..get a smaller bar!

When you have bust your balls in the woods for a while you learn....short bar good (light)/ long bar = hit the dirt I gotta to timeout and sharpen it !

oh...And straighten my back awhile......

At the end of the day....you could disappear into the darkness you show the pan everyday in an effort to perfect a system...but why chuck out excellent in pursuit of perfect?