Is it still cutting well? Good tooth length? If so take out a drive link and “use it until it’s used up”. But no they are not more prone to breakage but I would be wondering why it stretched that much.
I've never had a chain stretch out of adjustment range, but I understand it's common on the big west coast bars. Could the chain have started too long? There's some flexibility with drivelink count, but if a chain that's too long which squeaks by when new, could go out of range as it ages. Official policy is I need to lose at least one tooth before a chain gets retired to death run duty.
If a chain has been run dull and gotten hot so it stretched out to the end of the tensioner, just pitch it. The extended spacing on the links will increase wear on the sprockets (drive and bar). Keep your chains sharp. Dull chains create friction, which creates heat, which stretches chains.
And no, a new chain out of the box is not sharp. Sharpen it.
Lack of oil stretches them quickly too as well as lots of kickback and brake engagement. I've seen some guys who have a habit of hitting the brake after every cut, but before the chain stops, and by the end of a tank of gas the chain is sagging off the bar.
Chains have been known to break whenever.
If a new chain starts out with the tensioner most of the way out, I either use a bigger sprocket, or 1 less drive link, which means that sometimes I have to assemble the bar, chain, and sprocket before installing it as one unit on the power head. and let that chain just live on that saw until it stretches enough to come off. I had a 24" archer bar that was too long to let a standard 84dl chain go on with the rim already on the saw. Also a 92dl chain that was 1 link shorter than I needed, but I could barely get the rim on, then slide it all onto the clutch drum.
interesting, i always use the stihl depth gauge. doesnt matter how worn a chain is but i check each tooth. it says 0,65 on it, i assume that mm (metric). seems to cut like a raped ape and i heard thats whats important
If a short chain has stretched to the point it can’t be adjusted tight, it’s probably from running it dull. The drivers will be spaced further apart and will hammer out a new sprocket in no time. And the teeth will be so hammered that you’ll file away most of the cutters trying to get it to cut properly. I’d pitch it.
But a chain that still cuts and tensions properly can be sharpened until the teeth break off and won’t cut anymore
Sandy soil is a good one too.
An over-strecthed chain is a worn out chain. The rivets slanderize and their holes in the links enlarge. Take two or three links between thumb and finger and try to alternatively extend and compress (axialy) them. You can see the actual play in each knuckle. You'd be surprized.
Hey Bart! My thoughts on that would be that the kerf of the cut would be smaller so there would be less drag on the saw meaning it can run at a higher chain speed thus cutting quicker. Would not be an increase in hp though. But keep in mind that wood can swell in the kerf so when teeth get narrow the kerf is smaller so it’s closer to the bar and chain links so if the wood swells or pinches a little bit then the saw could get pinched sooner. I love a new chain where I can keep up on the sharpness. It always seems to cut better when the chain is new (longer top plates) and well maintained.
raker depth is suggestive for each person/saw/situation. Rakers ground low= more grab on the wood. Typically better for soft woods and ported saws. Rakers around the standard .025 is better for hard woods. Less grab on the wood allows the saw to run at a faster rpm while still cutting. Saw/bar length makes a big difference. If the saw is ported it can run higher tooth sprockets and lower ground rakers. If I’m running a 261 with 20in bar I like skip tooth and slightly lower rakers than 025. 500i with 25in bar she is getting ground lower. The saw has the power to pull through that wood with a lower raker. Pay attention to the type of green wood you’re cutting and how each saw acts in it. Check out the husqvarna chainsaw roller guides as well as the west coast saw depth gauge. They offer different measurements for raker depth.
I saw an animation of a saw chain working once, but I can't find where I saw it, and I can't think of a search term to bring it up. It's a little more complicated than you may imagine. It's a series of rocking motions on the raker that allows the tooth to bite at a certain depth. I think that may tie in to Sean's preference for a lower raker as the tooth wears, but I wanted to review the animation to construct a decent theory.
I don't think I take mine down as low as Sean, but it's lower than the stock .025 I start with. I use an averaging gauge to do the rakers. Progressive is supposed to be better, but I don't think it would make a difference for what I cut, and my sharpening ability.
I recently "restored" a chain I got from someone else: reground and dehardened the poorly hardened cutter, filed to the same length and sharp, then I used a depth gauge guide to even the mismatched DG's, but I couldn't reach them on the hardwood setting. So I filed them on the softwood setting since I was about to cut white pine, about as soft as it gets, and I had a hard time fighting kickback when boring. I don't know if it was the squishy AV on a modern saw, or if it was because I was boring in line with the grain (think triple hinge), or if they were too low. It was a full skip chain now that I think about it.
Full skip would be my guess. I've never run it on a big saw, but the 42cc poulans inexplicably come with skip chain by default. It's a chattery, grabby experience, and it would only be worse with more power, and working the nose of the bar.
I like a lower raker but I feel like the guide rail thickness opens up too quickly. I would imagine my bars would last longer than they do. What is an acceptable tolerance for the rail thickness? I run .050 chain
My opinion as to why lower depth gauges seem to wear the groove open quickly is because thicker wood chips are being jammed through it. It is easy to think there's just oily metal on metal wear going on, but there's actually a lot of wood on metal action going on in the groove causing lots of wear. 0.015" wider than the drive links is my preferred limit for what is practical to run. Small oregon bars are half way there especially after the paint wears out of the groove. I put .050 chain on their .043 bars when they are ready. Chinese made laminated bars like Archer start out at .012-.065" wider, so they are junk from the start. Archer solid .050 bars (also branded as Cross and likely Notch) start out at .055-.060 or so, so I run them a little, then put a .058 chain on.
I start using an averaging gauge at .025. I file without the gauge in place. I put the gauge on, see what the discrepancy is, remove the gauge, then count file strokes til it's right. I check the next ~3 rakers before completing the file stroke count. If everything's holding, I file the rakers by stroke count, and do a sanity check every several rakers so I know I'm on track.
As the chain ages, I eyeball a point inside the gauge. It's somewhere in the middle of the steel. It never drops below the gauge. Dunno what the exact number is. If the saw feels right when I'm done, I call it good. I've gone a little too far on my 2511. It does better when the rakers are left a little higher than I'd use on my big saws. Cuts smoother.