021 -- low profile 3/8 chain vs .325

[ajc4]

I was just inspecting the chain on my 021 to order a few new loops. The height of the cutters & tie straps are lower than all of my 3/8 chains. I had always assumed it was a .325 chain --- after careful inspection, the 021 has a stihl "pico" 3/8 pitch chain. Oregon calls these "low profile".

Why would Stihl do this? Since it is a small saw, why dont they just use .325? stihl usa indicates that the 025 & other small saws use .325. But on the 021 its 3/8 pico. The kerf the chain produces seems to be about as wide as a regular 3/8 chain. The cutters are the same width as a regular 3/8 chain -- just shorter.

It has always worked OK. Should I stay with the low profile chain, or just go ahead and use regular 3/8 chain for my new loops? The bar is still in good shape, and I dont want to buy a new one if I dont have to -- is there any compelling reason to switch to .325?

 

[16gauge]

The only thing I can think of is that the picco chain has less mass. Less hp used to turn the chain = more hp in the wood. They are also less expensive last time I checked. In their smaller saws Stihl seems to have done pretty extensive testing to get cutting performance. e.g. the 3/8 PMN 0.043 gauge chains on the 170s and 180s get over 10% faster cutting than with standard picco. Someone here has the answer. I'll be waiting for it.

 

[Billy_Bob]

I was thinking that for kickback situations, it would be the mass of everything moving that would cause the kickback reaction, and that maybe less mass might cause less of a kickback.

*I was just thinking this to myself, I did not read it anywhere.*

Anyway, I was thinking it would be desirable to have less mass in the moving parts, so maybe that could be a reason?

 

[Cut4fun]

Try this from the site sponsor Baileys. Made by Carlton. Semi chisel, non-safety. http://www.baileys-online.com/WPsawchain.htm

 

[Cut4fun]

Cant beat the prices either. http://onlinestore.forestindustry.com/cgi-bin/baileys/catch.html?product=1324

 

[Butch(OH)]

The kerf of the Stihl .375 Picco chain is narrower than the .375RS. Lots narrower actualy. I dont have the measurments handy but have run both. The kerf on the Stihl .325RS chain I use on our 400 Echo is the same kerf as full size RS.375. I dont believe you can mix and match 375 low pro and regular 375 chains and parts. Our 210 always dissapointed me for speed of cutting until we tried some Carton N1C. We now run that chain an all of our small saws that use low pro chain and could not be happier with the performance other than the factory sharpening leaves something to be desired and 4-5 strokes with a 5/32 file easily fixes that. Got my N1C through the mail from Tony Miller who posts on here.

 

[ajc4]

Thanks for the replies. The weight factor never occured to me. I'll try a loop of carlton as suggested here. I was just suprised to find 3/8, always thought .325 was for small saws. Butch says the pico is narrorer -- the with of cut *seemed* the same to me -- Never actually measured it. He's probably right. My 3/8 chains were pretty ground down, and the pico I have was a bit newer. Thanks for the advice.

 

[Diesel JD]

Oh yeah the 3/8" picco is way lighter and smaller than the .325" pitch. the Carlton/Baileys 30LP is what these guys mean, it cuts like a bat outta hell on my 009. I still would rather have 26RS or 35LG but I don't know how the 021 would perform with it. If you matched the sprockets and bars, you could run 3/8" PMN, 3/8" LP, or .325" pitch, STIHL also has 63PM non safety link but unless they work witha lot of pro arborists, if you ask for it your dealer will probably give you the PM1 and you say you want the pro stuff they'll look at you like you have an arm growing out of your head, haven't tried it but I hear it's good,
J.D.

 

[SawTroll]

3/8" low profile vs. .325

...... I was just suprised to find 3/8, always thought .325 was for small saws. .......

Narrower teeth and in combination with fewer teeth on the 3/8 picco/lo-pro adds up to less resistance in the cut, and makes it easier for a small engine to keep the rpms and chain speed up.

If you want to try .325, try a narrow kerf (NK) set-up.
It cuts about the same kerf as 3/8 lo-pro, but has more cutters (= cuts faster provided sufficient power). The weight is also somewhere in-between the other options.
It works great on a lot of smaller saws, but is not offered by Stihl. :umpkin:

I think Baileys has them both from Oregon and Carlton.
The Oregon 95VP has an anti-vibe chassis, and is probably smoother in the cut than the Carlton (never tried the Carlton).