Homemade chainsaw

[denhammotors]

What could go wrong?
Had a 18cc Weed Eater hedge trimmer that I didn't really have any use for, so I did a bit of modifying so that I now have a little 14" chainsaw. I have had it running the chain with no load fine, but the clutch will slip when trying to cut anything. I am pretty sure it is due to the clutch springs being the incorrect length, so it is not engaging at the proper RPM. Also, I think the clutch sprocket is pretty worn out. Otherwise the saw is perfect, but I do need to make some hand guards for safety and a top handle to hold it with.

 

[souperman000]

That thing is sweet. Ane deadly...

 

[Doc Sprocket]

Kewl- Did you molest an existing chainsaw for the clutch, bar, chain, and handle? You didn't by chance happen to score the chain BRAKE while you were at it, didja?

 

[machinist@large]

What could go wrong?
Had a 18cc Weed Eater hedge trimmer that I didn't really have any use for, so I did a bit of modifying so that I now have a little 14" chainsaw. I have had it running the chain with no load fine, but the clutch will slip when trying to cut anything. I am pretty sure it is due to the clutch springs being the incorrect length, so it is not engaging at the proper RPM. Also, I think the clutch sprocket is pretty worn out. Otherwise the saw is perfect, but I do need to make some hand guards for safety and a top handle to hold it with.

:ninja::ninja::angelsad2:

Oh man; where to start!?!

OK.. performance: most saws with a bar that long have engines in the 28 to 36 cc range; 18 is really on the light side. furious2

Safety: I would pull all the plastic off and take a good hard look at the frame of that thing, looking for the strongest places to bolt on top handle/ guarding. A weed wacker, while definitely dangerous, is a whole lot safer than a chain saw. It's not to often that you hear of someone losing limbs or their life with a weed wacker..... Chain saws??..... You get my point.

I wish you nothing but the best; it's just that, if it can cut down an average tree, it won't really notice parts of you body....

 

[denhammotors]

Kewl- Did you molest an existing chainsaw for the clutch, bar, chain, and handle? You didn't by chance happen to score the chain BRAKE while you were at it, didja?

Well, I had a bunch of chainsaw parts from when I found a chainsaw (with a seized engine) in someone's garbage. It wasn't worth fixing, so I just kept the parts, thinking I might someday use them. For some reason, the parts saw's chain brake was missing. The handle is actually from the original hedge trimmer that the engine is from.

 

[exenos]

I have to say that that is both scary and very ingenious at the same time. If the clutch is slipping try stretching the springs so you have a lower engagement and less force is being used to counter act the springs and more pushing on the drum.

 

[denhammotors]

OK.. performance: most saws with a bar that long have engines in the 28 to 36 cc range; 18 is really on the light side.

Yeah, I am definitely worried about whether or not this tiny engine has enough power to do even the lightest logging.

 

[denhammotors]

I have to say that that is both scary and very ingenious at the same time. If the clutch is slipping try stretching the springs so you have a lower engagement and less force is being used to counter act the springs and more pushing on the drum.

Thanks, I should try that. When I had a look at the clutch, one spring seemed to be more stretched out than the other for some reason. I think that it might be better to have a higher engagement speed, because the engine might not have enough torque to engage at such a low rpm.

 

[exenos]

yes, but you get the chain spinning up to full rpm before you start to cut right?

 

[denhammotors]

yes, but you get the chain spinning up to full rpm before you start to cut right?

Yeah I do, but the clutch starts to slip once the chain starts to cut anything.

 

[gvfc2]

cool little saw you got there. ever think about a gas powered blender? wouldve been a safer and maybe more useful tool

 

[landuse]

I would definately not use that for any sort of cutting. Even if you get hand guards etc for that thing, it is still going to be too dangeous. My life and limbs are worth more to me than showing people that I made a chainsaw. Have you ever heard of chainsaw kickback?? I have seen some photos of people where it was the last thing they saw!

I think it is cool that you were able to make something like that out of a weedeater, but in my book it was not the cleverest thing to make

 

[robbie]

I'm usually the guy who tells everybody to quit worrying so much, but holy crap!

I love chainsaws, I use them all the time, but I use only good ones. A well designed and well made chainsaw is a pleasure to use. There's nothing worse than a bad chainsaw, and I'm talking about real chainsaws that were designed from the start as chainsaws, by professional engineers. Chains come off, performance is poor, parts wear out or break prematurely, and you spend more time tinkering than cutting.

I love DIY projects, but in some cases it's more practical to just take advantage of decades of R&D. There are certain products where you are better off buying one from a factory because you'll be redesigning and rebuilding your home made one over and over before you get it right. I don't even like Craftsman or Homelite. How frustrating would a homemade chainsaw be? I'd be amazed if nothing went wrong for 30 seconds of cutting.

One other thing, I'm well known for saying "don't worry about it", but I wouldn't use a chainsaw with no brake. It's one of those dangerous things you avoid, just like whittling a stick towards yourself, or towards the hand holding the stick. It's just crazy.

Other than that, this is a very cool project. It has that effect visually, where I can't help saying "Wow, that looks cool!"

 

[ZnsaneRyder]

Has anyone considered using a large 4-stroke engine with clutch for a chainsaw?

Something like a 6.5 or 7HP Clone engine setup to drive a chain?

 

[souperman000]

Has anyone considered using a large 4-stroke engine with clutch for a chainsaw?

Something like a 6.5 or 7HP Clone engine setup to drive a chain?

Darwin may be here soon. (As well has Toystory!)

 

[exenos]

Has anyone considered using a large 4-stroke engine with clutch for a chainsaw?

Something like a 6.5 or 7HP Clone engine setup to drive a chain?

That setup would have less power than most mid to large chain saws, the only improvement would be in torque. It would be a lot less noisy though.

 

[denhammotors]

Has anyone considered using a large 4-stroke engine with clutch for a chainsaw?

Something like a 6.5 or 7HP Clone engine setup to drive a chain?

I think it would be way too heavy for a chainsaw. Having to carry around something like that would be a pain.

 

[robbie]

That's not so heavy. Check this out. http://www.youtube.com/watch?v=brfKKehFtmw

 

[incogrhino]

Ever cut yourself with a saw? I have. Be careful. Happens fast. Through chaps.

 

[smgs92]

I think it would be way too heavy for a chainsaw. Having to carry around something like that would be a pain.

a clone engine doesn't weigh anymore than my vintage 2 man chainsaw i could actually see it using an engine like that except it would be vertical shaft.