The Home Machinist!

I'm wondering what people think about gadgetry for sharpening chainsaws.

I really don't understand this stuff. When my saws start spitting dust, I put them on a bench and sharpen them with files. It takes maybe 5 minutes per chain, I don't need a vise or a jig, and when I'm done, the saws spit out big chunks and seem to cut very well.

Am I missing something?

I had a saw worked on recently, and the repair people messed it up. They also sharpened the chain, which I did not ask them to do. Now it seems like the file doesn't fit the way it should. It bottoms out in the indentations in the blade. I think I'm filing the links as well as the cutting surfaces. I suspect they ground off a ton of metal, maybe to put me in a position where I would have to buy a new chain sooner.

It does sound like that. It may also be the "last hurrah" for a blade which you or me sharpened incorrectly.

Saw shops seem to do that here, easily taking a third of the tooth off. I just use a Dremel and MK1 eyeball it.

I saw some guys on Youtube sharpening chains with a $600 machine. They said you have to use a depth gauge to keep the rakers (the little things in front of the blades) level with the blade tops. I had no idea. One more thing I have to buy. The depth gauge costs $5. They can forget about the $600 machine, though.

They also said you have to push the file toward the front of the saw, not the back. News to me.

I have no success with files; they work once and then go dull. There are diamond files but the prices are silly.
I have my chains sharpened by a shop who does a decent job for $2.
I took it to a closer shop who destroyed every single link, grinding off so much that the edges melted and curled over.
It all depends on who does the job.

But I don't use the chainsaw all that much in balmy Portugal.

Obviously you do not have one of those eucalyptus forests in your neighborhood. Much of Portugal appear to be infested with them. A great source of firewood, but then you probably do not need much firewood either in southern Portugal.

I will touch mine up once with a file and then the next time send it in to the shop to get it done correctly and back and forth. If not sharpened correctly, the chain can cut unevenly and may cause damage to the bar and then it will never cut straight.

http://www.madsens1.com/bnc_cut_pull.htm

I have a 1/2 acre of native pine forest; about 30 years old.
There are almost no old trees here; big old trees are so rare that if you see one you go "Wow, a tree!"
This is mainly due to forest fires.
I don't burn wood for heat but, I take out diseased trees and do some landscaping that's heavy enough to need a chainsaw.
Most forest here is neglected, and there is a disease that kills the pines. No one seems to know what to do about it; I took out about 30% of the trees, and always take out the sick ones.
My forest looks really good now, only lost 1 tree on the last 3 years. In contrast, neighboring properties are losing all of theirs.
But I have strength, machines, and time to use them.
I was offered $1,200 for the trees. 30 years, so that's $40 per year.
I told him thanks anyway, I'll let them grow.

I grew up in NW AL, where cutting wood with chainsaws was just part of life for many of us. Firewood (for use or sale), clearing to build etc, clearing from storms, not to mention a few working in the logging industry from time to time, and so on.

Everyone I knew (family, friends, and even a few semi-pros, etc) sharpened their own by hand with a round file sized and produced (no taper) specifically for the job. You don't touch the top of the teeth, so the rakers don't need any special tools or attention. You sharpen the tooth with the round file going underneath to produce the top edge along with keeping the upper portion of the vertical wall sharp as well. You do that until the teeth are largely gone (or in some cases start breaking when you hit something hard), and then you buy a new chain. I don't know that that's the absolute best way, but it's the way I was taught, did, and observed (universally). It only takes a few strokes per tooth if you don't let the saw get fully dull (or hit a nail/spike/rock). And once you sort of train your hands to maintain angle and advance, it was a maybe 5 minute easy task even on a long bar during a break while chatting or mind wandering.

Commercial sharpeners clearly have time/effort minimization goals, so positioning a power driven file for each and every tooth isn't going to be practical. So I would expect the better ones to use an indexing fixture to perform the same basic operation we did with round chain sharpening files, only with a disk, which would yield similar results. I would also expect cheaper/faster (more profitable) setups to just run over the tops. But I always thought(?) that the rakers were supposed to be below the cutting teeth, and if so, that would mean a second operation to deal with that due to reducing height in the primary sharpening operation.

But I, and I suspect most I knew back then, would have been very unhappy with that outcome. We were all very poor by most definitions (those of us doing best were still well below the "poverty line"). So our view would have been that we were not only paying for the work, but also shortening the lives of our chains.

The Internet dudes claim that if your teeth are too high above the rakers, the chainsaw will bite in like crazy and cause accidents. This was not something I would have guessed.

Me either. But as I said, the way we all sharpened our chains didn't require we concern ourselves with the rakers. If you had a quality chain, which in spite of being "dirt poor" we generally did (avoiding false economy), so the well maintained chains lasted quite a long time and always cut fast and freely without need for machines or tools to adjust the rakers.

Fun side fact, while I first started using chainsaws with my grandfather (gosh, I must have been about 10, can you imagine the cries of anguish now?), it was really my grandmother who taught me to really sharpen saws properly. Not touchups in the field, my grandfather taught me that, but rather how to take a chain that had been in the dirt/rocks a few times, or hit a spike (large nails often used for quick fences, signs, etc and then abandoned). Taking time to teach me how to set the compound angle, and maintain it stroke after stroke, tooth after tooth. With her guidance, starting slow, it soon became my job to go over all the chains and make them "right" before the saws were put away. Under her guidance, slow and steady to start, and got much faster over a few dozens, until I was quite fast and produced a nice uniform sharp chain, and I was proud of and acknowledge for that skill. Wow, the forgotten memories unfolding...

Whoever invented ethanol gas should be killed. With a 2-stroke yard tool. I know this is off-topic, but I have been working on chainsaws today. It's unbelievable what that stuff does to them, and it's all totally unnecessary. Ethanol isn't good for the environment, it wrecks engines, it doesn't save us money, it reduces mileage, it requires the creation of enormous amounts of evil CO2 by yeast, and it makes food cost more. I want to punch someone in the face, but I need a name.

I am inclined to think it doesn't matter which way one pushes a chainsaw file, since the metal can't tell. I do plan to observe the height of my rakers from now on. Sources say you have to make sure every tooth on your chain is as small as the smallest tooth; forget that. I don't care if my saw cuts slightly crooked. I don't intend to spend hours sitting with a file, dramatically reducing the life of my chain so I can get a pretty cut.