How did this chain get in this condition?

See pictures below. I'm helping a friend diagnose his chain and I've told him what I think is going on, but I'd like to get someone who knows more than me about chains and chain maintenance to weigh in. The chain is a Stihl RS being run on a 20" Rollomatic E bar powered by an 036. I've included a LONG top shot to show the general pattern of wear - it's slightly out of focus, but I think it gets the point across.

How? Chain is for cutting wood, it wasn't cutting wood by the looks of the teeth. Get a file, sharpen it up and be more carefull.

This is a new arena for me, so I'll take a couple of guesses and then see what the pros say.

1. B/C look like they're getting hot. (Dull chain? Oiler still working properly?)

2. Does he sharpen by hand? Uneven teeth and it looks like the rakers need taken down.

Yeah... That is supposed to be a wood cutting chain, not a rock cutting chain.
The build up of tree resin and dust on the chain indicates a lot of heat. Someone tried to cut for a while after rocking the chain.

PA Plumber said:

Oiler still working properly?

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Yes, bar oil is being transmitted along the whole bar length at the proper rate (it spins off the end). He has about 1/4 tank oil left after a full tank of gas burned.

Kinda looks like he's been digging a trench, and the rakers look maybe a tad high, but I don't see anything unusual. Sharpen it, and don't stick it in the dirt so much. At least he's enjoying the saw.

joesawer said:

Someone tried to cut for a while after rocking the chain.

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Ok now we are making progress. What indicates heat generation? Does anyone have anything to say about the wear pattern on the TOP of the plate? How about the approximate raker height relative to the top plate (leading corner)?

Depth gauges too low causing the cutters to rock?

.

I not a pro, just a weekend firewood cutter, but does the chain look like it has a lot of extra wear on the bottom of the links where they ride on the bar?
Has this chain been used a lot without being sharpend to often?

sperho said:

Ok now we are making progress. What indicates heat generation? Does anyone have anything to say about the wear pattern on the TOP of the plate? How about the approximate raker height relative to the top plate (leading corner)?

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The tar like build up is from heat, The damage on top of the cutter is on the front and back of the top plate indicates that the nose was against something hard. I can't measure the depth gauge highth. The wear on the bottom of the chain, where it contacts the bar shows a lot of pressure has been used trying to make it cut. I'm glad it is not my bar.

The first thing I'd ask your friend is what they were cutting??? Looks like they were cutting earth/rocks/trees.

boilerhouse47 said:

I not a pro, just a weekend firewood cutter, but does the chain look like it has a lot of extra wear on the bottom of the links where they ride on the bar?
Has this chain been used a lot without being sharpend to often?

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Yes.

LarryTheCableGuy said:

Depth gauges too low causing the cutters to rock?

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I was thinking just the opposite. The second pic looks like there isn't any depth set on the raker, but the third pic appears to have a little. (hard to tell with pics) The wear on the top of the cutter looks odd too, also leading me to believe the rakers are set too shallow. It appears the chain has been sharpened in the past. Have the rakers ever been taken down?

I'm going with, sappy softwood and rakers set too shallow.

boilerhouse47 said:

I not a pro, just a weekend firewood cutter, but does the chain look like it has a lot of extra wear on the bottom of the links where they ride on the bar?
Has this chain been used a lot without being sharpend to often?

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Thats what it looks like to me. I see irregular wear all over the top cutters and just above the drive links, looks like it's been used to make lots and lots of very fine dust after the chain was rocked out.

It also looks like the bar needs dressed pretty badly, looks mushroomed from lots of high heat wear, from lots of attemped cutting with a very dull chain.

Getting that back in shape with a file will be a chore, may be easier to have it profesionally sharpened, then keep the new angles and edges sharp with a file.

Instead of using the chainsaw as an excavater, use a stump grinder or a backhoe. Take that chain to the nearest trash can and dispose of it properly, or put it in the metal recycle bin so it can be melted down and start over. Before putting on the new chain clean out the bar groove of any dirt and I would probably pull the sprocket and give that a good cleaning also. I would also advise the chainsaw be used strictly for cutting wood and only wood.

Hmmm...

rreidnauer said:

I was thinking just the opposite. The second pic looks like there isn't any depth set on the raker, but the third pic appears to have a little. (hard to tell with pics) The wear on the top of the cutter looks odd too, also leading me to believe the rakers are set too shallow. It appears the chain has been sharpened in the past. Have the rakers ever been taken down?

I'm going with, sappy softwood and rakers set too shallow.

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I inclined to agree, by the gouging on the sides of the links it appears, as others have pointed out, he has been using it as a trenching tool too, or cutting really dirty sappy wood/stumps and not touching it up enough (baked on sap and rail wear would indicate this). Somethin' to be said about even minimal maintenance hmmm :hmm3grin2orange:

LarryTheCableGuy said:

Hmmm...

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??. whatchoo lookin' at there Larry? (raker height is from the top edges of the two adjacent teeth btw )

Sprig said:

??. whatchoo lookin' at there Larry? (raker height is from the top edges of the two adjacent teeth btw )

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Quite right, measure this way son.

The damage to the top of the cutter is from the chain used in other than wood. The wear on the bottom of the straps is from a loose chain and maybe high rakers. I have cleaned up chain that was way worse than this, and used it. No need to chuck it.