(NOTE: I have tried to replace lost photos in this thread - some may not be the same as the originals) Intro / Background OK, I can't port a saw like Mastermind and some others, but I can scrounge, save, and rehabilitate some chains that were not loved by their mothers, and restore them to useful life. The example in this thread looked like it lost a disagreement with a rock, especially on the left side of the bar. From the size of the right cutters, and some grind marks, it looks like it might have only been sharpened once, before this incident. Tragic loss of chain life. Peening on the bottom of the tie straps suggest that the chain was also run tight, or on a worn drive sprocket. I can only guess what I think that the chain is telling me as I received no other information on it. I believe it was run on a STIHL 460 with a 25 inch bar (3/8 pitch, .050 gauge, 84 drive links). OREGON Maintenance and Safety Manual - Look in here for some good diagnostic illustrations. Receipt / First Impressions U-G-L-Y. A lot of the chains I get are in the condition shown in the photo below. I can't see what I am working with until the chain is cleaned. I also don't want to get that junk all over my grinder, etc. *This is not the RS3 chain, but it is in similar condition as the RS3 was received, for reference. Cleaning From things I learned on this site, my 'standard' cleaning is now a bath in a sodium hydroxide (lye) cleaner, such as 'Super Clean' diluted 50% with water. I wear protective gloves and glasses. Even though this is consumer packaged, it can be nasty stuff, especially if it splashes in your face. Skip this step if your chain is fairly clean. A short soak and swish in a cut down jug will clean most average dirty chains. This chain took a couple of soaks, each followed by some light brushing with an old toothbrush. I try to do a few chains at a time so that I can get the most use of the cleaner ($8 - $10 per gallon). Start with the cleanest chains, then work towards the grunge. Soon, the solution will turn dark and stop cleaning so well. Rinse the chains well with a couple of changes of clean water. Note that this stuff will take ALL of the lubrication off of your chain, which can lead to rusting if stored in a damp place. I hit them with compressed air if I want to work on them right away. Otherwise, 15 minutes in a warm (150*F) oven to remove any moisture. Inspection Still U-G-L-Y, but clean. The results of the carnage are now evident. At this point I can inspect for cracks, broken cutters, tight links, poorly done field repairs, etc. I can read the stampings which identify gauge, etc. I can also break and shorten or lengthen a loop, or replace links or cutters, before sharpening. You will notice some light rusting around the rivets from the caustic cleaning. This will not be a problem unless left in a damp place or for an extended period of time to progress. No jokes about half the chain being upside down. No comments either about grinders removing too much cutter length. Almost half of those damaged, left side cutters need to be removed for the chisel chain to regain it's leading corner, whether you do it with a file, grinder, carbide cutter, etc. Then, the less damaged right side cutters will need to be ground back to match. A waste of a lot of high quality alloy. De-Burring This chain did not have burred drive links, but I see these frequently from chains that jump out of the bar groove. This is when I de-burr them using a ScotchBrite wheel on a bench grinder, before I sharpen the cutters. Working on a clean chain means that I can see what I am doing and that none of that gunk will get into my wheel or get thrown around the shop.