Chainsaw chain speed calculations

[romad10]

Did the math for most applications. Just thought I would share. UPDATED to include additional requests.






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[Finnlogger]

Nice information! Now if only the manufacturers used same standards to calculate their numbers...husqvarna uses chain speed at 133% of maximum engine power speed, some others at 100% of max power, some at max rpm.

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[romad10]

With this chart and an rpm gauge you would know exactly what you have...

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[Ted Jenkins]

From my experience too much chain speed becomes less efficient at top RPM. The older saws created less speed. The newer saws are much faster. It appears that manufactures understand that a smaller engine that is ported for higher RPM can produce more HP thus a smaller saw can compete with larger displacement saws. Probably there exists a balance from speed torque weight and displacement. The chains seem to stay sharper longer with a slower chain speed, but maybe under some conditions do not get as much wood cut. Just my take. Thanks

 

[happysaws]

It all depends upon how you sharpen your chain. An old saw running 9,000rpm with a wicked sharp chain will outcut a ported saw that runs 15,000rpm using a dull chain.
[emoji3]

 

[Definitive Dave]

Thanks for the chart you provided, it is fascinating.
Any chance you could run that chart up to include:
9-14 pin sprockets for the 3/8
6, 9-12 pin sprockets for pico
9, 10 pin for .404
9,10 pin for .325
those are all sizes guys do actually use on this forum (somewhat sparingly) and it would be cool to compare

I will say that actual chain speed at work (or play) is a delicate balance of the power of the saw, the wood being cut, the cutters style, the sprocket, the bar type and size, the chain length, type, gauge and sharpening style.

We did a shootout over the summer with 5 ported 064/066 models by different builders with a brand new stock chain vs a bone stock 064 with a great chain for the pine cant we were testing in and it wasn't close, the good chain smoked the ported saws.
thanks
Dave

 

[romad10]

Dave, ill chrck it out tomorrow..

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[happysaws]

......We did a shootout over the summer with 5 ported 064/066 models by different builders with a brand new stock chain vs a bone stock 064 with a great chain for the pine cant we were testing in and it wasn't close, the good chain smoked the ported saws...
Dave

[emoji106][emoji41]

 

[happysaws]

To the OP,
Thanks for adding more info to your charts!

 

[romad10]

Np

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[Definitive Dave]

wow many thanks, so my 372 3/8" chain is turning @125 feet per second and the 084 is going @135 fps

your chart shows picco and standard 3/8 as the same "size" but I think they are actually different size circles at least they are on all of them I have ever checked
in general you can run either chain on either sprocket in standard 7 pin size but as you get bigger it makes a real difference and even cut times with 7 pin standard and 7 pin pico on the same saw/chain/bar are different.
I'm not biotching, your chart is badass, just wondering why there is a discrepancy
thanks for your work I am saving this for reference.
there are also 11 and 13 pin sprockets for standard 3/8" available
My 084 ran fastest with an 11 pin sprocket but when actually racing my cutting style was more aggressive and the larger sprocket actually cost me speed in the cut.
@SquareFile told me to drop to 10 pin and when I finally followed his advice it made a huge difference.
Dave

 

[romad10]

your chart shows picco and standard 3/8 as the same "size" but I think they are actually different size circles at least they are on all of them I have ever checked
in general you can run either chain on either sprocket in standard 7 pin size but as you get bigger it makes a real difference and even cut times with 7 pin standard and 7 pin pico on the same saw/chain/bar are different.

3/8 low profile chain (also known as 3/8 Picco) is similar to standard 3/8" chain, but it has a shorter cutter profile and thinner chassis. This chain is popular with small consumer chainsaws, arborist chainsaws, and pole pruners, as well as specialty cutting systems. Much of this chain is designed for novice chain users, so it cuts fairly slow, but as safe as possible. Some varieties are designed for higher performance situations.

Hope that helps.

 

[DPO777]

Did the math for most applications. Just thought I would share. UPDATED to include additional requests.

View attachment 572308 View attachment 572309 View attachment 572310




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Nice Chart and good work. Can you upload the excel file so we can customize to or actual saw? My saw maxes out below 9000 RPM, more like 8,000-8,500

 

[DPO777]

Nice Chart and good work. Can you upload the excel file so we can customize to or actual saw? My saw maxes out below 9000 RPM, more like 8,000-8,500

Stihl MS170 with 16" bar (8600 RPM), crappy Poulan with 18" bar (9000 RPM), Stihl 041 farm boss with 20" bar (7000-7500 RPM), Stihl 090 with big bad bar (6500-8500 RPM)

 

[WI_Hedgehog]

I'm not even on the chart! Need 8,000 and 8,500 RPM.

 

[atpchas]

I'm not even on the chart! Need 8,000 and 8,500 RPM.

You could get the 8k speed by taking half of the 16k chart numbers. The 8.5k will be 1.0625 times the 8k values.

 

[WI_Hedgehog]

So I could make an addition to the chart in pencil and tape it on you're saying...

Or you could attach the XLS file and I could add it to MY chart and remove all you freaky speed freak numbers.

(of course giving credit to the original author in the footer)

 

[Philbert]

. . . you could attach the XLS file and I could add it to MY chart and remove all you freaky speed freak numbers.

I did a lot of this manually (OK, with a calculator).

Not hard for 1 or 2 saws. But not as extensive of a reference as @romad10 has provided.

https://www.arboristsite.com/threads/chain-saw-math.107300/
Philbert

 

[undee70ss]