Does Pitch matter when it comes down to replace a bar?

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

LilRobert1367

ArboristSite Lurker
Joined
Dec 21, 2018
Messages
10
Reaction score
5
Location
Colorado
I was wondering if the pitch matters when it comes down to replacing a chainsaw bar?

I've been rebuilding an old Mcculloch PM610 with a 20 inch bar (3/8 pitch sprocket/70DL/.050 gauge). When looking for a replacement 20 inch bar I see more chainsaw bar that say works with a pitch of .325 especially when it comes down to replacing it with a vintage new old stock 20" Mcculloch bar. So does pitch matter when it comes down to replacing the bar?
 
Okay thanks for clearing that up for me. Can to sprocket at the nose be replace from a .325 to a 3/8 or do you even know? I would rather keep it at 3/8 if I can.

The sprocket on the nose of the bar needs to match the pitch of the chain and also the pitch of the sprocket on the saw. Assuming you can get a .325 sprocket that will fit your saw, you could do it. Now, whether running .325 on that saw is a good choice is a different question
 
Can to sprocket at the nose be replace from a .325 to a 3/8
It depends.

Some bars are called 'Replaceable Sprocket Nose' ('RSN') bars; they have tips that can be replaced fairly easily when worn, or to change pitch. One style is shown below; there are different styles / shapes of replacement sprocket noses for different brands and models of bars.

Screen shot 2019-01-15 at 10.33.58 PM.png
On some other bars, the rivets holding the sprocket (and about 15 to 40 bearings) can be driven out and a new sprocket installed. This is much less common than it used to be, but if you are working with older style bars, a replacement sprocket that fits might be available.

Here is a link to show you what is involved, assuming that you can find the correct parts.

https://www.arboristsite.com/community/threads/nose-sprocket-rescue-illustrated.256640/

Philbert
 
Thanks you Philbert for your response. I'm still looking arounds but you gave me some really good advice that will help me along the way.

It depends.

Some bars are called 'Replaceable Sprocket Nose' ('RSN') bars; they have tips that can be replaced fairly easily when worn, or to change pitch. One style is shown below; there are different styles / shapes of replacement sprocket noses for different brands and models of bars.

View attachment 697288
On some other bars, the rivets holding the sprocket (and about 15 to 40 bearings) can be driven out and a new sprocket installed. This is much less common than it used to be, but if you are working with older style bars, a replacement sprocket that fits might be available.

Here is a link to show you what is involved, assuming that you can find the correct parts.

https://www.arboristsite.com/community/threads/nose-sprocket-rescue-illustrated.256640/

Philbert
 
I would really like to keep it at 20" I don't want to go anything bigger or smaller. I can find a few at 18" with the 3/8 pitch but alot more at 16' with the 3/8 pitch but having a hard with the 20" with the 3/8 pitch . I just thought it would be cool to keep it all Mcculloch brand instead of going with another brand since I can find other brand that will work but I didn't realize that vintage Mcculloch 20 inch bar would be hard to find at a 3/8 pitch. Yeah if you can find one that fits what I'm looking for sure i will consider it but at this point I may go with the old bar since its still in good enough shape, just need to do a little maintenance to it, I was just seeing what other opinions that were out there if I wanted to replace the bar or not.

I have some NOS OEM McCulloch bars, want me to check if one will fit a 610? Will probably be in the $80 area with the shipping.
 
If the bar has a replaceable nose sprocket the only thing to have the same is the pitch & bar mount, the gauge 050/058/or 063will all fit as the tip, is set to take the widest so will accommodate the narrower widths
 
I can find a few at 18" with the 3/8 pitch but alot more at 16' with the 3/8 pitch but having a hard with the 20" with the 3/8 pitch .
Bear in mind that there are different 'tail' / mount patterns as well. A bar marked 'McCulloch' on eBay may not fit your McCulloch!

@heimannm might be able to help you - he is kind of a McCulloch resource.

Philbert
 

Attachments

  • Oregon bar mount patterns.pdf
    2.1 MB · Views: 1
  • Oregon Bar Mounts old.pdf
    1 MB · Views: 0
I was wondering if the pitch matters when it comes down to replacing a chainsaw bar?

I've been rebuilding an old Mcculloch PM610 with a 20 inch bar (3/8 pitch sprocket/70DL/.050 gauge). When looking for a replacement 20 inch bar I see more chainsaw bar that say works with a pitch of .325 especially when it comes down to replacing it with a vintage new old stock 20" Mcculloch bar. So does pitch matter when it comes down to replacing the bar?

Oregon 20" Power Match Bar and Chain Combo 3/8" Pitch (200Rndd176 / 72Lgx070g) https://www.amazon.com/dp/B00470PXB0/ref=cm_sw_r_cp_api_i_O82pCbYPYEF9E

Oregon 200RNDD176 .050" Gauge 3/8" Pitch 20" Power Match Bar https://www.amazon.com/dp/B00AVLM1UK/ref=cm_sw_r_cp_api_i_r92pCbP8NSZMJ


Sent from my iPhone using Tapatalk Pro
 
To the OP - the 'roller nose' bars that @HarleyT posted do not have sprocket teeth, so the work with any pitch, and typically any gauge chain.

Philbert
The guage can change and that's one of the things that makes certain rollers more valuable than others. But as long as the guage is the same you can run whatever pitch chain for the most part.
 
I have at least 1 20" McCulloch bar, not sure if it's 610 mount though. When I get a chance I'll go dig out a parts 610.
 
I was wondering if the pitch matters when it comes down to replacing a chainsaw bar?

I've been rebuilding an old Mcculloch PM610 with a 20 inch bar (3/8 pitch sprocket/70DL/.050 gauge). When looking for a replacement 20 inch bar I see more chainsaw bar that say works with a pitch of .325 especially when it comes down to replacing it with a vintage new old stock 20" Mcculloch bar. So does pitch matter when it comes down to replacing the bar?
Any Oregon D176 bar will fit. This bar fits Poulan Series, Echo, McCullogh. It’s 3/8 pitch 70 drive links and very common
 
Back
Top