Husqvarna SM Rim 3/8P

[Tor R]

Hi,
I was wondering if it existed, or if there was a suitable Rim to get a 3/8p chain for a Husqvarna 242/346.
Is there a rim I could possibly machine?

I’m newbie in this subject

 

[SOS Ridgerider]

Hey Tor!

There are rims made that fit those saws. Not a common item, but they do exist. 6K Products, formerly Danzco, make some.

6K Products - .375 Picco Pitch Chain Saw Sprockets

www.6kproducts.com

I also bought one or two from Mike @Homelite410 years ago. He modified them from Stihl small spline rims, but I don't know if he still does this kind of work.

If you want anything from 6K products, let me now. I can order for you, and drop them in an envelope and send your way.

 

[el33t]

Another (European) source I guess:

P-3/8LP-7-SM Panther 3/8 Lo Pro SM Rim 7-7 tooth

P-3/8LP-7-SM Panther 3/8 Lo Pro SM Rim 7-7 tooth. Check and change your drive rim regularly to ensure maximum use out of your bar and chains.

www.chainsawbars.co.uk

You need to keep in mind that officially these chainsaws are too “strong” for 3/8 LP/mini/Picco chains...

 

[heimannm]

Stihl make a 3/8 LP (Picco) rim sprocket for their "mini" spline. The O.D. of the 3/8-7 LP (Picco) is about 1.435" compared to the 1.375" O.D. of a 3/8-7 sprocket. The LP (Picco) is larger due to the smaller chassis height of the LP (Picco) chain.







It is possible to grind the O.D. of a .404-7 sprocket (1.505") down to achieve the proper O.D. and pitch spacing for the 3/8 LP chain, but the difficulty will be finding a .404-7 sprocket in anything other than the standard (large) spline.



Mark

 

[mainer_in_ak]

Another (European) source I guess:

P-3/8LP-7-SM Panther 3/8 Lo Pro SM Rim 7-7 tooth

P-3/8LP-7-SM Panther 3/8 Lo Pro SM Rim 7-7 tooth. Check and change your drive rim regularly to ensure maximum use out of your bar and chains.

www.chainsawbars.co.uk

You need to keep in mind that officially these chainsaws are too “strong” for 3/8 LP/mini/Picco chains...

That is not true. I have been milling with 3/8lp stihl pmx chain for years now, which is very hard on chain. Mostly on a ported 67 cc saw using a 20" gb milling bar. I'm also running it on an 81 cc ported saw. The chains hold up fine.

 

[el33t]

That is not true. I have been milling with 3/8lp stihl pmx chain for years now, which is very hard on chain. Mostly on a ported 67 cc saw using a 20" gb milling bar. I'm also running it on an 81 cc ported saw. The chains hold up fine.

But you realize that milling and “classic” use of a chainsaw are a little different things?
Stihl has a 3/8 Picco spur sprocket (P/N 1122 640 2006) that can be used with saws such as the MS 660, etc. Milling with such a kit is officially supported by Logosol, for example.

Oregon stipulates 3/8 LP .050 chains for use on gas chainsaws with engine capacity up to 42cc.

In Stihl docs you can sometimes find the recommended maximum engine power for a particular type of chain. And it also depends on the type of machine. For pole saws this power is higher.
For 3/8 Picco .050 you can find their recommended maximum power of 1.9 kW, which did not prevent them from equipping the MS 241 with such a chain in the Super version. The official maximum power output of the MS 241 is 2.3 kW.

Oregon for the 3/8 LP .043 (Type 90) does not change the recommended maximum engine displacement of the chainsaw and it is also 42 cc. Stihl for its 3/8 Picco .043 (PMM3) chain recommended a maximum of 1.5 kW, but for the latest PS3 Pro (.043) chain this power is already 2 kW.

 

[chipper1]

But you realize that milling and “classic” use of a chainsaw are a little different things?
Stihl has a 3/8 Picco spur sprocket (P/N 1122 640 2006) that can be used with saws such as the MS 660, etc. Milling with such a kit is officially supported by Logosol, for example.

Oregon stipulates 3/8 LP .050 chains for use on gas chainsaws with engine capacity up to 42cc.

In Stihl docs you can sometimes find the recommended maximum engine power for a particular type of chain. And it also depends on the type of machine. For pole saws this power is higher.
For 3/8 Picco .050 you can find their recommended maximum power of 1.9 kW, which did not prevent them from equipping the MS 241 with such a chain in the Super version. The official maximum power output of the MS 241 is 2.3 kW.

Oregon for the 3/8 LP .043 (Type 90) does not change the recommended maximum engine displacement of the chainsaw and it is also 42 cc. Stihl for its 3/8 Picco .043 (PMM3) chain recommended a maximum of 1.5 kW, but for the latest PS3 Pro (.043) chain this power is already 2 kW.

It will all be just fine lol.

 

[el33t]

It will all be just fine lol.

I agree. That's why I wrote "officially". These quoted values whether engine displacement or horsepower probably include a fair margin of safety to reduce the chances of successful lawsuits (in the US).

Besides, they are very coarse data. E.g. they don't take into account the number of teeth/pins in the sprocket, the length of the bar, etc.
It's a shame that manufacturers don't include chain parameters in their public catalogs, such as tensile strength, which can be found for harvester chains.

I must also admit that my dad (not a pro) once somehow managed to break a 91 VXL chain using a 35cc chainsaw. The chain and sprocket were in rather good condition. I expect he caused it by doing something stupid, and it was not due to the torque of the engine. Of course, he did not admit it.

 

[Bill G]

This morning I ordered a variety of them from Stihl for a 261..............
One hour ago I sold the saw

 

[chipper1]

I agree. That's why I wrote "officially". These quoted values whether engine displacement or horsepower probably include a fair margin of safety to reduce the chances of successful lawsuits (in the US).

Besides, they are very coarse data. E.g. they don't take into account the number of teeth/pins in the sprocket, the length of the bar, etc.
It's a shame that manufacturers don't include chain parameters in their public catalogs, such as tensile strength, which can be found for harvester chains.

I must also admit that my dad (not a pro) once somehow managed to break a 91 VXL chain using a 35cc chainsaw. The chain and sprocket were in rather good condition. I expect he caused it by doing something stupid, and it was not due to the torque of the engine. Of course, he did not admit it.

Pretty sure most guys can manage to figure out what they can and can't do.
The chains that I've seen break were from poor condition bar sprocket or the rim/spur in normal use, racing is a whole different ball game as the power is greatly increased and most guys do a lot of chassis work on their chains knowing there's a chance they could break.

 

[chipper1]

This morning I ordered a variety of them from Stihl for a 261..............
One hour ago I sold the saw

I have a 20" 3003 setup in picco, i removed it from a 261. The only place I would use it is on tree work that cleanup is of the utmost concern, other than that, I see no benefit on a saw with enough power to run 325 or 3/8 if were talking about the same bar length.
I really like it on all my 35cc and smaller saws, it does a great job.

 

[Bill G]

I have a 20" 3003 setup in picco, i removed it from a 261. The only place I would use it is on tree work that cleanup is of the utmost concern, other than that, I see no benefit on a saw with enough power to run 325 or 3/8 if were talking about the same bar length.
I really like it on all my 35cc and smaller saws, it does a great job.

I run 33RS-72 on all 12mm mount saws but I try to accommodate varying preferences

Hell I have ran 33RS-72 on a 090G

 

[el33t]

3/8 standard and dedicated 3/8 LP rims differ in size, but certainly many people use LP chains with standard 3/8 rims.
Moreover, for example, in the Archer catalog for 3/8 LP and 3/8 standard chains they stipulate the use of the same rims, e.g. with 7 pins.

 

[Tor R]

Thanks for the great input everyone, it was very educational for me.
Now I know a little more about how complicated it is to reach 3/8P where we normally only get 325 and 3/8 to choose from

 

[chipper1]

3/8 standard and dedicated 3/8 LP rims differ in size, but certainly many people use LP chains with standard 3/8 rims.
Moreover, for example, in the Archer catalog for 3/8 LP and 3/8 standard chains they stipulate the use of the same rims, e.g. with 7 pins.

Can you believe archer would do such a thing .

 

[el33t]

Can you believe archer would do such a thing .

Personally, I'd rather not use such a combination, as I don't think it does much for the health of the chain, but many people on the Interwebs swear that there is zero problem with such a setup.

Anyway, as you wrote, there's no point in trying to use 3/8 LP with such chainsaws, because the current selection of .325 chains is sufficient, especially after Stihl introduced the Pro versions of .325/.050. Unless one has a supply of free 3/8 LP chains....

 

[Woodwater]

i have used a standart 3/8 rim with 3/8 picco chain.

after 10 minutes you can throw both in the garbage.

 

[Wonkydonkey]

i have used a standart 3/8 rim with 3/8 picco chain.

after 10 minutes you can throw both in the garbage.

Yes I totally agree, it’s like using a 404 sprocket and a std 3/8 chain.

A long time ago, someone was using a std 3/8 sprocket and a 3/8 lopro chain ( milling) and didn’t know why the chain kept snapping.
He showed numerous pics and then the q got asked what rim sprocket are you using..

Anyhow the company that supplied the setup replaced it with a lopro sprocket and a new chain, they have since learnt from this mistake ( I don’t know if it was a new employee or a genuine mistake).

 

[el33t]

Yes I totally agree, it’s like using a 404 sprocket and a std 3/8 chain.

I don't think it's a good idea either, of course.
On the other hand, comparing this situation with using a .404 sprocket with a 3/8 standard chain is not accurate, because here you are dealing with different pitches.
3/8 standard and 3/8 mini are the same pitch. What is different is the chassis.

 

[Wonkydonkey]

Another (European) source I guess:

P-3/8LP-7-SM Panther 3/8 Lo Pro SM Rim 7-7 tooth

P-3/8LP-7-SM Panther 3/8 Lo Pro SM Rim 7-7 tooth. Check and change your drive rim regularly to ensure maximum use out of your bar and chains.

www.chainsawbars.co.uk

You need to keep in mind that officially these chainsaws are too “strong” for 3/8 LP/mini/Picco chains...

I’m not sure if you know ? . But stihl does/did sell a kit , it was for a ms261 it was a 3/8 lopro 16”chain bar & sprocket. Here’s a link
Ms261 kit link.