chain identification and file to use

[commanche 2]

hello.on my chain on my craftsman their are 2 sets of numbers.1 is down on those things that slide in the bar.it says 20a .on the side above where cutters are itsays 25.its a oregon chain.how do you tell what file you have to use on chain.also do they have a chart of some sort i can look at on this so i can tell what file to use and angles etc?my saw is 18 inch 3.8.it is 35 years old.,

 

[sedanman]

http://www.oregonchain.com/tech/tech_guides.htm http://www.oregonchain.com/tech/cross_ref_guides/OCS_65.pdf
http://www.oregonchain.com/tech/cross_ref_guides/OCS_82.pdf

 

[commanche 2]

wow, that answered it.now i know what that A means and the 25 on top near cuterrs.you know, my sears manual had me using a 7/32 file all these years.35 years ago.that 20a chain takes a 3/16 not 7/32.thanks for info.great.

 

[sedanman]

That's what we're here for.

 

[commanche 2]

my owners manual said the 917.353760 model takes a 7/32 file.after looking at chain it said 20a,which is 3/16 chain file.does it matter if the chain is 3/16 or 7/32 on this saw.saw is 35 years old.3.7 18 inch.thanks

 

[TimberPig]

So long as the chain, bar and sprocket all match in pitch, and the chain gauge and gauge the bar takes are the same, it will be fine. If you've had it this long without problems, then they should all be matching, although parts could be getting worn if they are original and have seen significant use. The saw was likely spec'd with either 3/8's chain (7/32 file) or .325 chain (3/16 file), and either is acceptable to use as a matched cutting attachment.

 

[geofore]

those things

Those things that ride down in the bar are drive(link)tangs. You use the file to touch them up also. If you've ever thrown a chain you've probably damaged them. Get an Oregon Maintanance and Safety Manual, page 65. I'd post a pic but I think you'd be be better off getting the manual at their site, www.oregonchain.com and download the pdf and read the explaination on page 66.