Thread: CSMing with Lopro chain

Thanks!

That’s very helpful, I’m really glad to hear that Low Profile is limited to shorter bars.

I don't own a mill, but have to say that is thinking laterally. I have used 3/8 lo pro in smaller saws, but thought that Pico was a different type of 3/8 lo pro again, used mainly for pole pruners and tiny homeowner saws. ?
In my experience LoPro breaks very easily when it gets hot, or someone over tightens the chain, especially on hardwoods, so am surprised that you can use it for such as demanding application, but understand the rationale, as why make more sawdust than you need. Having said that, I have almost never broken a 3/8 regular chain.
Was there a reason that you didnt use .325? I would have thought that would be a good compromise of smaller kerf, but still enough structural guts to handle the demands of milling.

Originally Posted by quercus

I don't own a mill, but have to say that is thinking laterally. I have used 3/8 lo pro in smaller saws, but thought that Pico was a different type of 3/8 lo pro again, used mainly for pole pruners and tiny homeowner saws. ?

Stihl's Pico cutter type (assigned label P), with a micro cutter shape (assigned label M), with "3/8 extended" pitch (assigned number is 6) and 0.050" gauge drive links (assigned number 3) has an all up designation of PM63 has the same specifications as Lopro.
It is indeed used in some smaller saws ( i.e. less than 50 cc) although they usually use PMM3.
PM63 is the standard chain used on Logosol CSMs

In my experience LoPro breaks very easily when it gets hot, or someone over tightens the chain, especially on hardwoods, so am surprised that you can use it for such as demanding application, but understand the rationale, as why make more sawdust than you need. Having said that, I have almost never broken a 3/8 regular chain.
Was there a reason that you didnt use .325? I would have thought that would be a good compromise of smaller kerf, but still enough structural guts to handle the demands of milling.

I'm using Carlton chain Lopro on my 441 with a 25" 0.050 bar and have never broken a chain but several loops have come off the bar before the bar nose wore in enough to hold it on the bar.
When I bought the Lopro I was essentially following what some CSMillers were experimenting with in North America.
We thought it would fit all our existing 3/8 sprockets and didn't realise the complications.
Fortunately a turned down 404 7 pin fits the Lopro pitch.
If .325 was the go I would have thought that the North Americans would have gone for it.
Now that I have gone this way I will just stay with it as the last thing I need is yet another set of chains, bars and sprockets.

In north american softwoods there are CSM'ers using Lopro on 660's and even 880's on up to 36" bars.
As the cutters get shorter the risk of losing cutters increases much more than regular 3/8 chain.
One CSMer says he loses too many cutters and has to dispose of these chain before the cutters are used up.

Hi Bob and co.

I just wanted to add a few comments.

First... A disclosure in case it's not clear by my signature, my company Ideal Tools is the distributor of Logosol Swedish chainsaw mills in Australia.

I agree with Bob that the 3/8th low profile chains may not run on some bars properly because the nose sprocket is not suitable. His image of the sprocket tip not riding down properly is a good example. On bars we have specifically made for 3/8th Low Profile chains there is a small amount of rise of the chain on the bar at the nose, but not that much as in Bob's example. Watch out for that. I've never had a 3/8th low profile chain come off a bar that is suitable designed for it. Would not want to, yuck.

I do disagree with some about the length of bar that is suitable for 3/8th low profile chains. I regularly use 50cm, 63cm and 90cm bars and only when I step up to a 120cm bar do I switch to a standard 3/8th chain. This is for ripping only, and ripping Aussie hardwoods with both smaller 60cc and larger 90cc saws and these bars is no problem in my experience. One thing to note though, I/Logosol use chains with the teeth ground to 10 degrees specifically for ripping, which is a lot less stress on the chain and saw than cross cutting chains 30-35 degrees.

One last comment, if chainsaw milling, a thin kerf chain at 10 degrees does create a little less sawdust and give a better yield, but the main reason we do it because you need a little less chainsaw power and you get a nicer finish on the boards.

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Originally Posted by nt900

I agree with Bob that the 3/8th low profile chains may not run on some bars properly because the nose sprocket is not suitable. His image of the sprocket tip not riding down properly is a good example. On bars we have specifically made for 3/8th Low Profile chains there is a small amount of rise of the chain on the bar at the nose, but not that much as in Bob's example. Watch out for that. I've never had a 3/8th low profile chain come off a bar that is suitable designed for it. Would not want to, yuck.

I do disagree with some about the length of bar that is suitable for 3/8th low profile chains. I regularly use 50cm, 63cm and 90cm bars and only when I step up to a 120cm bar do I switch to a standard 3/8th chain. This is for ripping only, and ripping Aussie hardwoods with both smaller 60cc and larger 90cc saws and these bars is no problem in my experience. One thing to note though, I/Logosol use chains with the teeth ground to 10 degrees specifically for ripping, which is a lot less stress on the chain and saw than cross cutting chains 30-35 degrees.

One last comment, if chainsaw milling, a thin kerf chain at 10 degrees does create a little less sawdust and give a better yield, but the main reason we do it because you need a little less chainsaw power and you get a nicer finish on the boards.

Most chains saw millers would use are filed/ground to a 10º top plate filing angles - it is after all a standard ripping chain profile.

I too believed that a higher top plate fining angle would produce a bigger kerf and have measured the kerf generated by various chains, including Lopro, with different top plate filing angles.

I have done this many times in a couple of different ways and reported some of these these on the arborist site. My measurements show that on new chains the 10º versus 25º or 30º top plate filing angle (on any chains) makes little difference in terms of kerf size with any differences in the thousands of an inch and all within measurement tolerance.

There may be an more noticeable effect on older chains as the worn chain means it is able to tilt more in the bar groove.

What the lower (10º) TPFA does do is produce is less vibe and is capable (if the operator is not too rough) of a better finish.

I have also not observed any differences in engine temperature between low or higher angle top plate filing angle chains which suggests the load is not that different.

I've been using .325 chain for milling since I got my farmers logosol around 1.5yrs ago. Thats running a 9 or 10 tooth sprocket (10 tooth custom made) on big saws (3120xp,dolmar 166 etc). 10 tooth chain speed is very close to 8 tooth .404. for a bar it was a simple matter off swapping a sprocket nose on a gb bar. This is fast for chainsaw milling, very fast.

Have recently tried .325 on a 44" hardnose bar, stretched quickly on the 166 settled down after 30mins and has been stable since. quick pic off an alaskan milled 2m sheoak piece.

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Originally Posted by Iron.and.Bark

I've been using .325 chain for milling since I got my farmers logosol around 1.5yrs ago. Thats running a 9 or 10 tooth sprocket (10 tooth custom made) on big saws (3120xp,dolmar 166 etc). 10 tooth chain speed is very close to 8 tooth .404. for a bar it was a simple matter off swapping a sprocket nose on a gb bar. This is fast for chainsaw milling, very fast.

Have recently tried .325 on a 44" hardnose bar, stretched quickly on the 166 settled down after 30mins and has been stable since. quick pic off an alaskan milled 2m sheoak piece.

20161123_174345.jpg20161123_174345.jpg

Sounds interesting. It would be great to see some video some time if at all possible.

Happy to, but will be a few weeks till I mill again.

Milling speed varies depend apon the saw and chain brand used. Currently using a roll of archer chain .325, while seems to hold it"s edge adequately it has an overly large kerf and is slower than a name brand chain. Though as I cut alot of dirty craft wood, I tend to use semi chisel ground to 10°, cuts slower but holds an edge longer.