Cutting speeds of different size chains, .325 vs. 3/8

[bigbluram]

My ms 260 is definitely faster in wood over 4 inches with 3/8 than .325 but is much more grabby in the small stuff . I run 3/8 full skip on a 20" bar and it will pull it buried in white oak with ease,saw just has muff mod and wt 194 carb... 325 just seems to pack up n not clear as well for me in bigger wood.

 

[Philbert]

My ms 260 is definitely faster in wood over 4 inches with 3/8 than .325 but is much more grabby in the small stuff . I run 3/8 full skip on a 20" bar and it will pull it buried in white oak with ease,saw just has muff mod and wt 194 carb... 325 just seems to pack up n not clear as well for me in bigger wood.

Are you comparing skip to skip?

Philbert

 

[memory]

So by the looks of it, 3/8 cuts faster because of being able to clear the chips better. I figured with everything being equal, sprocket, hp, that .325 would cut faster but I guess not. I guess that is why you don't see .325 chain on the bigger saws.

Anybody have any input on if a Husky 460 rancher could pull a 20" bar with a 3/8 chain?

 

[Philbert]

I guess that is why you don't see .325 chain on the bigger saws.

The chain needs to be matched to the powerhead. Smaller 'frame' chains (e.g. 1/4, 3/8 low pro, .325) do not have the physical strength that larger 'frame' (not sure what the correct term is here) chains such as 3/8, .404, etc. The additional torque and length (longer bars) require heavier tie straps and rivets, etc.

The chains would have to be heavier, which would be additional drag on the smaller saws.

I keep going back to the analogy of tires. Just because a pick up truck or sports car runs a specific size/type of tire, does not mean that you should run that on Prius or Civic.

Philbert

 

[rms61moparman]

A similar 3/8ths running on a 7 pin and a .325 on an 8 pin will cut very similar.
A .325 has more cutters per foot but the 7 pin 3/8ths rim is bigger.



Mike

 

[memory]

A similar 3/8ths running on a 7 pin and a .325 on an 8 pin will cut very similar.
A .325 has more cutters per foot but the 7 pin 3/8ths rim is bigger.



Mike

I am talking if everything is equal.

 

[echoshawn]

So by the looks of it, 3/8 cuts faster because of being able to clear the chips better. I figured with everything being equal, sprocket, hp, that .325 would cut faster but I guess not. I guess that is why you don't see .325 chain on the bigger saws.

Anybody have any input on if a Husky 460 rancher could pull a 20" bar with a 3/8 chain?

I've run a couple 460 ranchers, 1 fitted with a 20", the other a 24". Both running 3/8 full comp. The 20" never felt lacking for power. The 24" was working hard, but no real issues, even with the bar buried. The 24" did prefer a skip in big wood, but was more than adequate either way.

 

[groundup]

Yes, but 3/8" chain doesn't have exactly a 3/8" pitch - it is just a "name". :biggrin:

Why is called 3/8's? Just curious

 

[bigbluram]

Are you comparing skip to skip?

Philbert

I personally don't have any .325 skip but find no real difference in 3/8 skip or full comp until its time to sharpen , then 1/3 less teeth is great

 

[memory]

Why is called 3/8's? Just curious

Isn't 3/8's the width of the chain?

 

[echoshawn]

Isn't 3/8's the width of the chain?

No, someone please feel free to correct me if I'm wrong, but if memory serves me right, it's the distance from rivet to rivet.

 

[bigbluram]

No, someone please feel free to correct me if I'm wrong, but if memory serves me right, it's the distance from rivet to rivet.

Divided by 2

 

[shelby bankston]

No, someone please feel free to correct me if I'm wrong, but if memory serves me right, it's the distance from rivet to rivet.

ported 346 16'' bar 3/8 h-47 chain 7 pin sprocket . Just flat out rips hard wood soft wood. ok go ahead burry the bar it still cuts like a banchee . love it just dont take the rakers down to much

 

[lambs]

No, someone please feel free to correct me if I'm wrong, but if memory serves me right, it's the distance from rivet to rivet.

It's the distance across any 3 rivets, divided by 2.

 

[SawTroll]

Isn't 3/8's the width of the chain?

No, it is the pitch = the distance between 3 rivets, devided by two. That is what determines how the sprockets should be.
The width is about the gauge (of the drivers), and determines how wide the bar has to be between the rails.

 

[memory]

Oops, what I meant to say was the cutting width of the chain. Isn't the cutting width of a 3/8 chain also 3/8's?

 

[rms61moparman]

Oops, what I meant to say was the cutting width of the chain. Isn't the cutting width of a 3/8 chain also 3/8's?

No.

That is the kerf.


Mike

 

[Philbert]

I personally don't have any .325 skip but find no real difference in 3/8 skip or full comp until its time to sharpen , then 1/3 less teeth is great

They clog less in bigger wood.

Philbert

 

[SawTroll]

I personally don't have any .325 skip but find no real difference in 3/8 skip or full comp until its time to sharpen , then 1/3 less teeth is great

Not really, as you will have to do it more often, when there are less cutters to do the same job. :msp_wink:

 

[bigbluram]

I personally don't have any .325 skip but find no real difference in 3/8 skip or full comp until its time to sharpen , then 1/3 less teeth is great

Not really, as you will have to do it more often, when there are less cutters to do the same job. :msp_wink:

That may be true in your world where you just cut perfectly clean bark free wood but in my world of working the piss outa my saws dirt in the bark or hitting the ground bucking thru or stumping is a fact of life so it usually needs a stroke or two of the file at least every other tank of gas regardless of skip or full comp.