Chain hit metal or a rock

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Stelcom66

Minister of Fire
Nov 6, 2014
791
Connecticut
I was cutting a round and saw sparks. Sure didn't expect that, because I was cutting a leftover piece of a round. Or maybe a large branch, it's like it grew around a nail or a rock. I have seen that happen before, Anyway, is there a chance the chain could be sharpened to at least make it somewhat effective?
Probably not, but I may give it a shot anyway, So disappointed as it's a new chain. I've had success doing routine sharpening with a Dremel tool.
 
How badly damaged are the cutters?
 
This subject has sparked many debates here, with some hand-filers claiming anyone hitting a rock, bolt, nail, or electrical insulator in a tree must be a moron. But it happens to me at least once per year, often more, and I just swap the chain out. I have a bench grinder in my shop, and will sharpen it the next rainy evening when I have nothing better to do, rather than trying to bring it back to life in the field with a hand file.

Others swear by their cordless Dremel type grinders, and I can see their merit, but I've never tried them.

If you're heating with wood, you'd do well to keep 2 - 3 chains for each of your saw/bar combos. This way you can swap chains and deal with a wrecked one later, when your outside or on-site trying to get work done.
 
Saw didn’t hit metal but wood hit my saw. Is this an easy fix???? [Hearth.com] Chain hit metal or a rock
 
I was cutting a round and saw sparks. Sure didn't expect that, because I was cutting a leftover piece of a round. Or maybe a large branch, it's like it grew around a nail or a rock. I have seen that happen before, Anyway, is there a chance the chain could be sharpened to at least make it somewhat effective?
Probably not, but I may give it a shot anyway, So disappointed as it's a new chain. I've had success doing routine sharpening with a Dremel tool.
It usually damages only a few cutters on one side; that is if you stopped as soon as you felt it and/or saw sparks. Just file those cutters back to rights, adjust those rakers to match, and off you go again (file the whole chain of course, but fix the damaged cutters). It matters not one bit if some cutters are shorter or longer than others as long as the profile is correct and each raker is adjusted for each tooth.
 
I was cutting a round and saw sparks. Sure didn't expect that, because I was cutting a leftover piece of a round. Or maybe a large branch, it's like it grew around a nail or a rock. I have seen that happen before, Anyway, is there a chance the chain could be sharpened to at least make it somewhat effective?
Probably not, but I may give it a shot anyway, So disappointed as it's a new chain. I've had success doing routine sharpening with a Dremel tool.
Yes you can probably make it usable again, or i should say it can be made usable with the right tools.
But that may depend on what you have to sharpen the chain.
There is a debate on weather all cutters have to be the same lenght...
The biggest asset when sharpening or fixing a chain is your knowledge,then the tools to sharpen.
If you don't know what the teeth on the chain are actually doing,or how a sharp cutter looks when it has been properly sharprned then all the tools in the world will not get you a good result.
 
The blades didn't look really damaged, just didn't feel sharp and they were creating sawdust. I bought the saw a few weeks ago. There was no clue that I could see that something other than would was inside the round. I sharpened the chain with a Dremel, I know not the ideal way and without precision, but it's good enough now to use until I can get a new chain.

Don't want to got to Tractor Supply on a Sunday morning a few weeks before Christmas.
 
The blades didn't look really damaged, just didn't feel sharp and they were creating sawdust.
I remember with my first saws (teenager), I'd look at a chain and think it looked and felt sharp, but it'd be throwing dust, whereas I knew it once threw chips. Even now, decades later, it's still easier to judge a chain by how it cuts than just looking at it.

If it's throwing chips, keep running. If it's throwing dust, stop to sharpen or swap.
 
you can flounder and fart around your whole life or you can watch someone who knows how.

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and you don't need a vice, you don't need to get behind the saw, the chain doesn't have to be tight when you file, yadda, yadda, yadda. You just need to know what a good tooth is supposed to look like and make it that way.
 
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you'd do well to keep 2 - 3 chains for each of your saw/bar combos.
This is good advice, especially when out in field or woods and a prolonged sharpening session would prevent you from getting job done.

It's common for chain to throw sparks when cutting near the base of tree where bits of rock/ dust concentrate in the bark (trees near roads and field rows). It's noticeable if you cut at night (not that you should, but some people need to).

The problem with rocking your chain hard is not that it can't be filed back to tip-top condition, but that in doing so it will require filing much of the tooth (and other teeth ?) and you'll forfeit much of your time and burning daylight (especially if you are a hand filer). WIth chain going 60 mph there really isn't any reasonable reaction time, just being fortunate if not too many teeth damaged, or too severely.
If chain rocked bad, consider retiring the chain to status of junk chain, especially if nearing end of its life, for when you ever need to use for bad conditions.
 
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You can get an idea how sharp the chain is by looking at it but it's not easy. At my age it requires reading glasses.

Sometimes there can be metal embedded deep in a tree from something that was nailed to the tree long ago. If it was fencing there may be some still sticking out to warn you but if it was just something nailed to the tree 100 years ago there may be no external clue. Even in deep woods there can be metal in trees. When I was working for the forest service measuring trees there were a couple times I broke an increment borer off inside a tree. They're hardened steel about 3/8" diameter. Hopefully when those trees got harvested and milled they found it with the metal detector before it took out the bandsaw.

Sometimes the nail is so deep that there's no sparks or other sign except the chain suddenly stops cutting. My place was a farm 120 years ago and had fencing everywhere. So there's some trees that had nails in them. When I have hit embedded nails it's damaged a few teeth beyond what can easily be sharpened. You can sharpen the rest and do the best you can on the heavily damaged teeth. Especially if it's a long chain you won't notice much difference.

It takes practice but it's worth learning how to sharpen chains well. There's a lot of tools to do it. Many people swear the 2 in 1 sold by Stihl and Pferd (who makes good files). I have not yet tried one. People obsess over depth gauges (which those tools also file) but I find that they don't need attention very often. (yes I have gauges to check). I used a bare file for years but lately have been using the basic Oregon guide that's just a flat plate that clips to the file.

One reason to have multiple chains is if you damage a chain in the middle of felling a tree, you don't want to leave the tree half cut and waiting for a strong wind to maybe push it over while you're filing your chain.
 
With my gas chainsaw (this is a new battery saw for quick/small cuts) I've had a spare chain in the garage, good idea. I'll definitely replace this chain as I know how good it was supposed to be when it was throwing chips.

And now I feel foolish. Flipped the round over and there's a couple of thick wires coming from it. Still strange in how it's coming from the round, if does appear it grew around it. Still 'living and learning' at this senior age.

You can get an idea how sharp the chain is by looking at it but it's not easy. At my age it requires reading glasses.

Sometimes there can be metal embedded deep in a tree from something that was nailed to the tree long ago. If it was fencing there may be some still sticking out ...

Join the reading glasses club! I'll see if I can get a photo later of the culprit. Other good and interesting info there - the ancient nails/fencing or whatever will be less obvious. I've heard good things about that 2 in 1 Stihl tool.
 
With my gas chainsaw (this is a new battery saw for quick/small cuts) I've had a spare chain in the garage, good idea. I'll definitely replace this chain as I know how good it was supposed to be when it was throwing chips.

Don't throw out out, just buy another couple chains. Use the damaged one for sharpening practice. Actually you'll practice on all of them, that's just the first in line.

And now I feel foolish. Flipped the round over and there's a couple of thick wires coming from it. Still strange in how it's coming from the round, if does appear it grew around it. Still 'living and learning' at this senior age.

It happens to nearly everyone sooner or later. It's probably not worth the time to inspect every round carefully for those once in N years events.
 
If you use a saw sooner or later you'll hit something and have to either buy a new blade, pay someone else to sharpen it or buy the tools and learn how to sharpen it. No matter which camp you're in a saw that you use should always have a spare sharp chain because stuff like this always happens at an inconvenient time.
 
Definitely a good idea to have a spare blade on hand. Here's what caused the damage - the cuts you see aren't from yesterday, that I did on the other side evidently right in line with the wire. Based on the sparks I would have thought it was a nail. or something like the clamp holding the wires together. Maybe there's another one of those inside, Just my luck I hit it.

[Hearth.com] Chain hit metal or a rock
 
Sometimes the nail is so deep that there's no sparks or other sign except the chain suddenly stops cutting.
Spoken like someone who actually knows what they're talking about. I've hit electrical fittings and lags so deep in trees that there's no way anyone would feel or see it, before the chain is toast at full RPM. I laugh every time someone claims their experience allows them to stop before losing more than a tooth or two, they're clearly not cutting where I am.

The worst for me have actually been ceramic electrical insulators. It seems that when they electrified our area 100 years ago, they put a lot of hangers in trees. Now, 100 years later, they're so grown into the tree that you will almost never see them.

However, on depth gauges, I do file them down when I sharpen. Stihl RS-3 is spec'd for .026" down from cutter, but I usually take mine down closer to .035" for better speed. Do note you can't do this if you run big bars on small saws, consider 18 - 19 inches max on 65cc or 28 inches max on 85cc saws, if taking a cut this big in hardwood. It will also make the saw a bit more grabby, so felling dogs with good lower teeth and a heavier saw can be your friend, if going this route.
 
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A ceramic insulator must really mess up a chain. So far I have only found them on the outside of trees.

I have experimented with deeper depth gauge settings but so far I have not seen a huge advantage. Also we have nine species of trees that range from easily cut fir and madrone to hard live oak and eucalyptus, and I never know what I'll be cutting next.

Madsen's has a good page on depth gauges for those who are interested in reading more: (broken link removed to http://www.madsens1.com/bnc_depth_gauge.htm)
 
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I correcttge tooth as much as possible and then goon with life. Tge other teeth will eventually get down to that level.

Re hand filing. I used to bring chains in to have them ground, until once I got one back that had huge discolored burrs hanging off. Whoever was grinding the chain hung on it and ruined the temper. I paid my $10 for it and figured it'd take me a long time to do that damage with a file. It was a cheap lesson. I filed incorrectly for a long time after that. No matter what my skill level was, the result was always better than when I started filing. Eventually I got pretty good at it.

Like an idiot I let someone borrow the saw that came from a family that sold Oregon chains. I figured it was safe. I got it back with the chain so loose that it was about to fall off. Immediate bad feeling. Yup, no bar oil. After lots of oil I was able to tighten the chain and start filing. It took 6 filings to get the chain back to sharp. I learned a lesson I should have known. I took the incident to deep clean and go over the saw.

Hand filing works well and can correct a lot of damage.
 
Bars need love too, it's not just about the chain.


You're right. I used a spray lube to get the bar and chain at the same time. It only had to last 7ntil the oiler reprised and took over it's job.