What the heck is LP chain for?

[noyb72]

OK, first time ever in a real saw shop today, very enjoyable experience. Nice couple a guys who are going to take care of all my saw woes.

So one of my woes is a pinched bar on my PP 260. What makes it a real woe is the BRAND NEW chain for that bar (NO ONE MAKES A 62 drive link bar that I can find.) They agreed to take my new chain in on trade for a new chain that fits a used bar they have that fits my saw. All good so far. So the guy goes back to put it all together for me (nice of him,) and then comes out and asks "why are you running low profile chain on this saw?" Which baffles me because I thought a .050 LP sprocket wouldn't run 3/8" chain. They assured me it would and then put the full size chain on the saw.

So my question to you all is, why on earth would you run LP chain if you could run full size chain?

Thanks
Ron

 

[Stihl #1]

The main reason for LP chain is that it has less mass, or bulk or weight, whatever, so the engine can pull it around the bar easier, so it makes more horsepower available to cut. The small saws perform better with 3/8 LP chain, where a standard 3/8 chain would cut slower and possibly stall.
My old Stihl 020 had 1/4 chain on it, and with so many rivets it stretched like crazy, so they came out with low profile 3/8, same pitch so it doesn't stretch as bad, but a lower height with less mass so the saw could pull it.
My boss has a Logosol mill with 2 066 saws on a double ended bar, and we made upo a 3/8 LP chain, ground at 10 degrees, mainly so it would cut a narrow kerf and not waste as much wood, so it has an advantage there.

 

[noyb72]

OK, that makes sense, thanks

Ron

 

[ray benson]

Looking at the Oregon selector guide- the pp260 calls for 3/8 lp chain.

 

[aandabooks]

When you get that saw in wood with that setup get back to us with how it ran. The PP260 is a 42 cc saw, correct? I had thought of doing this with my Craftsman so I could run a larger chain but realized that it pulls the low-pro but wouldn't handle full 3/8.

 

[noyb72]

This saw alredy has the limiters pulled and I am going to mod the muffler (louver style) prior to any cutting. This should make it quite a bit more powerful, opening up the carb to the limiter helped alot. So, we'll see. It won't be that big of a deal to switch back to LP.

Thanks again
Ron

 

[RED-85-Z51]

This is relavent to my interests...

On my PP260, I tried to put 3/8pitch regular profile semi chisel chain on....and it wouldnt work with the sprocket, which was new btw. I put it on the bar, off the saw, and it didnt work on the bar either..it would bind and skip over so many teeth.

I put 3/8" LP on it it worked fine.

This is a 40cc saw, btw...2.6ci

The drive links are different...make sure your chain moves smoothly and freely by hand, take it around a few times..if it isnt smooth like glass, it wont last long.

When I had mine on..it would catch and mess up, and if revved at all it would hop off the bar and scare the jeebus out of me as it slammed into the chain catcher. 2 of those in 2 minutes was enough for me to put 3/8LP back on it.

My guess...you wont be impressed...the LP has a purpose..So smaller saws can make better use of the available power. As far as cutting..it cuts really quickly.

 

[windthrown]

OK, first time ever in a real saw shop today, very enjoyable experience. Nice couple a guys who are going to take care of all my saw woes.

So one of my woes is a pinched bar on my PP 260. What makes it a real woe is the BRAND NEW chain for that bar (NO ONE MAKES A 62 drive link bar that I can find.) They agreed to take my new chain in on trade for a new chain that fits a used bar they have that fits my saw. All good so far. So the guy goes back to put it all together for me (nice of him,) and then comes out and asks "why are you running low profile chain on this saw?" Which baffles me because I thought a .050 LP sprocket wouldn't run 3/8" chain. They assured me it would and then put the full size chain on the saw.

So my question to you all is, why on earth would you run LP chain if you could run full size chain?

Thanks
Ron

Low profile, or PICCO chain is good stuff for smaller saws. Personally I run and prefer 3/8 standard size chain on my larger saws, and LP on the small ones. I do not like .325, which is sort of between LP and standard chain, with 0.063 rails.

 

[heimannm]

Is LP .375?

I thought I read in another thread that 3/8" LP is really like .365 and not intended to run on .375 sprockets. Is there more than one LP out there, some actually .375 and some .365"?

Curious...

 

[aandabooks]

I've seen SawTroll post that a few times. Not sure how that works out since your measuring center to center and the difference in numbers is .010.

Matt

 

[noyb72]

RED-85-Z51
Were you using the factory bar with that chain? The guy at the shop said that LP tends to be more flexible and that is needed for the narrow nose Poulan anti-kickback bar. The bar I'm putting on is more conventional and is not narrow at the tip at all. I am also having them put on a new sprocket.

All I can say is we'll see.
Thanks

Ron

 

[RED-85-Z51]

I thought I read in another thread that 3/8" LP is really like .365 and not intended to run on .375 sprockets. Is there more than one LP out there, some actually .375 and some .365"?

Curious...

Exactly.

All out 3/8"LP chain is Identified as .365 and all our non LP 3/8" is .375

Id you found a 3/8" non LP sprocket, and are putting on a 3/8" bar, then it should work, and by work I mean spin around. As far as cutting, I still feel like you will be disappointed.

For one it is a heavier chain, a beefier chain, and cuts a wider Kerf. It will immediatly feel awesome, you cut a few logs, and it seems to cut faster, but vibrates more in the cut..

Then you will relaize that the saw is really loaded up in an 8" log..and that you are only able to self feed the chain..

In the end...back to LP.

----

I like LP on smaller saws..regardless of bar style. My Husky 350 has 3/8" LP, and honestly it feels comfortable with that chain. It's not like the saw couldnt pull .325 or 3/8"...but it would just make it harder on the saw than it should.

I like .325 on mid sized saws with mid sized bars, like 20" or so. My 520 likes the .325, it's pretty smooth.

3/8"...good chain, needs a good bit of power to turn it with a buried 20"+ bar.

 

[kevlar]

The log builders around here prefer the lp as well 20' bars on 660's.I'm surprised at its strength some breakage but not very often.

 

[maccall]

I thought I read in another thread that 3/8" LP is really like .365 and not intended to run on .375 sprockets. Is there more than one LP out there, some actually .375 and some .365"?

Curious...

This has been discussed many times, a search would give a lot of info, but a short resumé of what I think is the collective visdom is:

* All 3/8 chain is actually .367, the numbers .365 and .375 are just used to distinguish low profile 3/8 from standard 3/8, but has nothing to do with the actual pitch.

* You can not run low profile 3/8 on a drive sprocket for standard 3/8, several members has recently experienced repeated chain breaks and other mishaps when trying this. No saw/bar/chain manufacturer has ever approved to this setup either.

* The reason for this not working should be that the drive tangs on the different 3/8 chains is differently shaped in an incompatible way.

Because of this I take it for granted that the reverse is also true: You can not run a standard 3/8 chain on a drive sprocket for low profile since the drive tangs are shaped differently.

If you run this setup, the standard 3/8 chain you got now might not break as easily as a low profile, but you might get weird results and it might mess up your sprockets.

 

[SawTroll]

I thought I read in another thread that 3/8" LP is really like .365 and not intended to run on .375 sprockets. Is there more than one LP out there, some actually .375 and some .365"?

Curious...

Both are .367 - the .375 and .365 is only "names", and used by some to ditinguish them....

 

[Mad Professor]

The main reason for LP chain is that it has less mass, or bulk or weight, whatever, so the engine can pull it around the bar easier, so it makes more horsepower available to cut. The small saws perform better with 3/8 LP chain, where a standard 3/8 chain would cut slower and possibly stall.
My old Stihl 020 had 1/4 chain on it, and with so many rivets it stretched like crazy, so they came out with low profile 3/8, same pitch so it doesn't stretch as bad, but a lower height with less mass so the saw could pull it.
My boss has a Logosol mill with 2 066 saws on a double ended bar, and we made upo a 3/8 LP chain, ground at 10 degrees, mainly so it would cut a narrow kerf and not waste as much wood, so it has an advantage there.

Sorry to hijack the topic but, what did your boss do to allow two powerheads to be used on a logosol (I've got a M5 logosol)

 

[noyb72]

Wow!!

Well it works!

I don't know if it is the muffler mod, the full size chain or the carb tune, but this saw is now cutting like a house afire!!

Literally, my job keeps me pretty busy and the kids take care of the rest of my time. So I normally cut firewood out of my pile of seasoned trees for the week on Sunday. I'm lucky to get a weeks worth of wood in an hour, I just cut two weeks of wood in 2/3 that time! I have some more time today and I think I'll get all of February cut today!! I will write up the mods later, I learned some things but for right now I just want to say THANK YOU to everyone who has answered all my silly questions about saws and guided me to where I am now. A couple months ago I barely new saws needed bar oil and today I'm running a saw with a pro bar and chain on a new sprocket that I replaced (didn't even know you could do that,) with a mild muffler mod and limiter caps removed and tuned. You all have directly impacted my familys quality of life. Thank you again.

FTC(SS) Ronald L Jones

Now I'm going to cut some more wood