Some interesting facts about 3/8" lo pro chain and milling....

[Rob D]

It often comes up in chainsaw milling - what about using a lo pro chain that takes a smaller kerf and therefore is less wasteful and faster?

 

 

I was looking into getting some bars produced similar to the logosol bars that run the Stihl picco ripping chain.

 

 

But then came across this thread here http://www.arboristsite.com/milling-saw-mills/137465.htm

 

So in summary an idea of the kerfs taken by different chains:

 

.404 takes a kerf of 8.6mm

 

3/8" takes a kerf of 8.3mm

 

3/8" lo pro takes a kerf of 7.2mm

 

 

In my mind I was thinking 3/8" lo pro would take half the kerf of .404 chain when in fact it is only 20% larger.... So in a big log over 10 cuts this is saving 14mm or just over 1/2" - not exactly that much more wasteful on a log that would otherwise have been firewood anyway.

 

.404 compared to standard 3/8 only takes .3mm more! A tiny difference. I used to run a 3/8 standard ripping chain on a cannon 36" bar with MS880 and it always felt slower than .404.....

 

Also in terms of speed and stay sharp I've always found .404 faster and stays sharp longer.

 

So it does imply that if you have the torque and power in a saw to run .404 chain for most scenarios this is the best option for efficiency when chainsaw milling.

 

 

 

 

 

[MikeTM150]

That is interesting, in the small addictive amount i've done so far has been with .404" chain and i'm well impressed with its cutting speed and not too bad at staying sharp seeing as it's ripping!

[agrimog]

the pico ripping chain that I use on my logosol bar takes a little over 1/4", even my local stihl dealer cant get it, it comes direct from sweden through logosol, on specimen trees cut for boards, its a big saving on a large dia tree

[offgridchris]

interesting stuff. i did a similar test on some wood a while ago. also i mocked up a series of logs on google sketch up and calculated the difference in kerf when cutting thin boards for roofing shingles, and the difference in the number of boards produced. the difference between the bandsaw blade and a .404 wasn't as much as you would think, around 1 or 2 boards per small diameter log. i can dig out the file if anybody really wants it. this is why i stayed with a chainsaw rather than buy an old bandsaw mill.

 

rob i tried to phone you on this very topic last week. i'll try again on monday. what im after to cut all these boards is speed. and i suppose the time to sharpen chain has to be included in the speed of milling. may be its a .404 ??

[Rob D]

the pico ripping chain that I use on my logosol bar takes a little over 1/4", even my local stihl dealer cant get it, it comes direct from sweden through logosol, on specimen trees cut for boards, its a big saving on a large dia tree

 

 

I know you can't get the stihl picco ripping chain here - but this is what I was trying to illustrate - your chain takes just over 1/4" (which makes sense as what I think this other guy measured around 7.2mm).

 

But .404 chain was measured at 8.6mm...

 

So for every cut you save 1.6mm

 

So if on a large diameter tree you did 15 cuts = a saving of 1".

 

I wouldn't describe this as a big saving at all....

 

 

 

So what I'm getting at is there is a myth that lo pro picco chain means you save a lot of kerf - this post seems to indicate that this is not true - savings are very small.

[Rob D]

what im after to cut all these boards is speed. and i suppose the time to sharpen chain has to be included in the speed of milling. may be its a .404 ??

 

 

Sorry out and about a lot at the mo but I'd say for pure speed you'd be looking at playing with setups that use a large powerhead, .404 chain and then a shorter bar....

 

So perhaps an MS880 with 20" or 21" bar running .404.... then try varying the chains (i.e. try a granberg vs oregon vs stihl) and/or also try lowering the depth guages a fraction more (but not too much or you'll just get huge vibration and a faster dulling chain).

[offgridchris]

fitted the new bar chain and sproket ( 8 tooth). the cut was quicker than the 3/8 chain and should stay sharper longer. kerf sizes personaly ii think the difference between lo pro and .404 is more like an 1/8th but the small chain does dull quicker. more tests to follow in regard to speed and water cooling.

 

as i mill more it seems to come down to feel. and out of all the setups ive tried the .404 feels nicer more glide and pull to the cut. it just feels right.