So I've been starting to mill with lopro chain for the past month or two, and thought I'd share some of my experiences. I started with adding an open ended small log mill to my arsenal for the purpose of resawing 2"+ hardwood slabs to single piece cutting/charcuterie board thicknesses. I got a 20" bar, lopro sprocket from Chainsawbars in England because lopro gear isn't sold in the US except for chain and got Stihl PMX from Baileys because they were out of Woodland Pro (just as well, I later bought some WP that I returned because the teeth were irregularly ground in the most haphazard fashion imaginable). I paired it with my 64cc Makita. I get about a 17" cut with the small log mill. Found you have to be careful not to put the inside post too close to the powerhead or it will butt up against it and force the bar out of level. Worked fantastic for resawing short pieces, super light rig I could work on a table top with. Ultra smooth finish, the best I've gotten out of milling yet. Even went through a lead slug from a bullet embedded in mesquite without any harm at all to the chain and minimal dulling.
I started on some mesquite logs I had but due to crooked lumpiness of mesquite had to go to a wider setup after a couple of cuts. I bought a 36" setup as well which I meant for a larger saw but ran it with the Makita on my regular Alaskan mill doing seven slabs out of a six foot long, 15-18" mesquite log (for the Aussies, the hardness of mesquite is roughly comparable to blue gum). Though I would have done better touching up the chain after three slabs or so, I did seven slabs without sharpening or retensioning the chain. Noticeable loss of speed in the latter slabs, but still acceptable. Now the common wisdom of why lopro is not good to mill with is chain stretch and breakage in larger saws. No evidence of that, and if anything the chain stretched less than some of my 3/8 and .404 chains do breaking them in. I think the lesser resistance from much smaller teeth combined with not pushing hard at all and letting it self feed means much less force applied to the chain when cutting, so stretch not an issue.
I finally got my 87cc 045 Super running okay after a long and problematic top to bottom rebuild, and tried it with the 36" setup on some short 25" ash slabs yesterday. I thought I broke the chain after a bit only to find one of my bar mount bolts had vibrated loose and the bar had popped off the tensioner and thrown the chain. Resharpened the chain and second cut started well but then thought it was a bit slower than hoped through the rest. Took that slab off the log to find I'd gone right through a nail. Now conventional wisdom again on lopro is nails will destroy it. It continued to cut amazingly well after going through that nail and no obvious chain damage. Sharpened again and did one more slab which went quite well though still maybe not as fast as hoped for, but might have been more to do with my sharpening. Have been using a Pferd 2 in 1 file with good results but doesn't take down the rakers as much as I'd like, particularly when the teeth get filed back a fair bit as they've been already (I think the one I'm using was a Stihl PMX used chain I got as a bonus in a demo package) and the rakers need to come down to .040-.060 how BobL likes them. I think the Pferd raker file in the 2 in 1 is non-adjustable and set for only .025.
My thoughts have been that lopro may have diminishing returns in cuts over 30" which is why I only got a 36" bar (plus greater chance of bar flex). It may be over 24" or so that its advantages become less noticeable. Someone on another forum doing a 30" spruce thought maybe it was a little slower than his old 3/8 setup but liked the finish a lot more. For dimensional lumbermaking with a CSM I think it's hands down the way to go, and for resawing to thinner stock, but will likely depend on the 880 for larger full sized logs. Mainly got it for mesquite which I mill a lot of and rarely gets over 24" and is the third hardest wood in North America. Smaller logs are usually milled for thinner boards which means you want the narrowest kerf you can outside of a bandsaw to get the least waste.
I started on some mesquite logs I had but due to crooked lumpiness of mesquite had to go to a wider setup after a couple of cuts. I bought a 36" setup as well which I meant for a larger saw but ran it with the Makita on my regular Alaskan mill doing seven slabs out of a six foot long, 15-18" mesquite log (for the Aussies, the hardness of mesquite is roughly comparable to blue gum). Though I would have done better touching up the chain after three slabs or so, I did seven slabs without sharpening or retensioning the chain. Noticeable loss of speed in the latter slabs, but still acceptable. Now the common wisdom of why lopro is not good to mill with is chain stretch and breakage in larger saws. No evidence of that, and if anything the chain stretched less than some of my 3/8 and .404 chains do breaking them in. I think the lesser resistance from much smaller teeth combined with not pushing hard at all and letting it self feed means much less force applied to the chain when cutting, so stretch not an issue.
I finally got my 87cc 045 Super running okay after a long and problematic top to bottom rebuild, and tried it with the 36" setup on some short 25" ash slabs yesterday. I thought I broke the chain after a bit only to find one of my bar mount bolts had vibrated loose and the bar had popped off the tensioner and thrown the chain. Resharpened the chain and second cut started well but then thought it was a bit slower than hoped through the rest. Took that slab off the log to find I'd gone right through a nail. Now conventional wisdom again on lopro is nails will destroy it. It continued to cut amazingly well after going through that nail and no obvious chain damage. Sharpened again and did one more slab which went quite well though still maybe not as fast as hoped for, but might have been more to do with my sharpening. Have been using a Pferd 2 in 1 file with good results but doesn't take down the rakers as much as I'd like, particularly when the teeth get filed back a fair bit as they've been already (I think the one I'm using was a Stihl PMX used chain I got as a bonus in a demo package) and the rakers need to come down to .040-.060 how BobL likes them. I think the Pferd raker file in the 2 in 1 is non-adjustable and set for only .025.
My thoughts have been that lopro may have diminishing returns in cuts over 30" which is why I only got a 36" bar (plus greater chance of bar flex). It may be over 24" or so that its advantages become less noticeable. Someone on another forum doing a 30" spruce thought maybe it was a little slower than his old 3/8 setup but liked the finish a lot more. For dimensional lumbermaking with a CSM I think it's hands down the way to go, and for resawing to thinner stock, but will likely depend on the 880 for larger full sized logs. Mainly got it for mesquite which I mill a lot of and rarely gets over 24" and is the third hardest wood in North America. Smaller logs are usually milled for thinner boards which means you want the narrowest kerf you can outside of a bandsaw to get the least waste.