CSM ... sorta

[BobL]

All i'd be using it for would be wide live edge slabs, and only on occasion.

For occasional use, in that case a simple alaskan mill is the way to

A 20hp motor new can be had for $1000, or out of a beat up old riding mower for next to nothing. I wouldn't have room for a giant BSM, or the amount of work to justify it.

A 20HP motor is not going to pull a band straight, through a 6ft cut. It will drive a 6ft bar on a CSM - I'd be looking at the design of Lucas slabbers.

The saw i'm interested in building would be similar to the Dolmar saw on the Talarico Hardwoods website. It's just a simple frame with a big bar & chain. That one looks to have a hydraulic motor, though, which makes sense for RPM & torque purposes.

I wouldn't exactly call that setup simple.

 

[DaltonPaull]

I wouldn't exactly call that setup simple.

I'd call it rad. I didn't know Dolmar made anything like that.

 

[splitpost]

c'mon splitpost.... you ought to know better than to quote spammers ;-) It just makes life tougher all round. But I'm sure the spammer is thankful!

Shaun

:bang::bang:was a big day,got home and saw that post and was wondering what this guy was smoking ,did not even click it was spam,to buggered i suppose:yoyo:

 

[qbilder]

For occasional use, in that case a simple alaskan mill is the way to


A 20HP motor is not going to pull a band straight, through a 6ft cut. It will drive a 6ft bar on a CSM - I'd be looking at the design of Lucas slabbers.


I wouldn't exactly call that setup simple.

I'm not doing a 6' bandsaw, no way no how. If I do it, it'll be CSM. It'll be simplistic in design, like a manual BSM except that instead of a band & wheels it'll have a bar & chain. The Dolmar is a pretty sophisticated machine and far more complex than i'm attempting. But the nuts & bolts are the same. Basically a 6' bar & chain powered by a 4-stroke and runs on a guided track like a BSM does. Bar sag was something I have not considered. I have never milled with a chainsaw before, let alone a long bar. That's something i'll need to consider.

I think I can build the mill for about $1000 or less. The big expense will be the bar and chain. I can find an old mower engine pretty easy. Aside from bar sag, what other issues should I expect to encounter?

 

[BobL]

I'm not doing a 6' bandsaw, no way no how. If I do it, it'll be CSM. It'll be simplistic in design, like a manual BSM except that instead of a band & wheels it'll have a bar & chain. The Dolmar is a pretty sophisticated machine and far more complex than i'm attempting. But the nuts & bolts are the same. Basically a 6' bar & chain powered by a 4-stroke and runs on a guided track like a BSM does. Bar sag was something I have not considered. I have never milled with a chainsaw before, let alone a long bar. That's something i'll need to consider.

I think I can build the mill for about $1000 or less. The big expense will be the bar and chain. I can find an old mower engine pretty easy. Aside from bar sag, what other issues should I expect to encounter?

You can't run a 4 stroke mower engine at WOT (well you can but it won't last very long and even at WOT it probably won't generate the necessary RPMs) so you won't get enough chain speed from the motor sitting at 3000-3500 rpm. You will then need either a gearing/pulley system and/or a bigger drive sprocket. If you use too big a drive sprocket the chain might not ride proper down onto the bar so you need to be careful as to how big you go. Additional cutting speed can be obtained by lowering the rakers by an extra 50% over the regular setting it will vibrate quite a bit but should cut like a hot knife through butter. For an engine with that much power I would use 0.404" skip chain.

You will also need a chain oiler of some kind - check out the CSM 101 sticky.

 

[qbilder]

Thanks for the advice, Bob.

 

[Hillbilly3995]

I've been experimenting with my 6' bar to see how I can get around the bar sag issue (insert joke here) as when I mount that on the mill I get about 1/4" droop (insert joke here as well). Right now I'm trying to fabricate something similar to what BobL has done with an independant nose for chain tension, but with another tensioner to "pull" the bar tight and prevent it from sagging.

I figure in this manner I can put as much tension on the actual bar as I want, then tension the chain separately. I have found that it takes a significant amount of tension to take the sag out, and will likely have to bulk up other components of the mill to handle the strain, but that it can be done.

And I completely agree with the last statement. My "$200" mill is going to end up being 2-3x more expensive than planned. Unless of course if you ask my wife, because as far as she knows I am on-budget and schedule.

Have you tried viagra in your premix?...lol
(sorry I'm so juvenile I just HAD to)

Shaun, the other big factor to me is that a band sharpener is wicked expensive, I already have a chain grinder. - Hillbilly

 

[huskyhank]

Positioning the bar vertically would solve the bar sag problem.

How about a motorcycle engine and transmission for power? Maybe even water cooled! I bet you could find a wrecked bike with plenty of power and cheap enough. Adjust the ratio from the output shaft to the saw chain sprocket to get the speed you want. I'd guess 8-10,000 RPM at the chain drive sprocket? Or it might last longer running slower? I'd look at how fast the industrial chain saws of similar type run.

 

[imagineero]

Positioning the bar vertically would solve the bar sag problem.

How about a motorcycle engine and transmission for power? Maybe even water cooled! I bet you could find a wrecked bike with plenty of power and cheap enough. Adjust the ratio from the output shaft to the saw chain sprocket to get the speed you want. I'd guess 8-10,000 RPM at the chain drive sprocket? Or it might last longer running slower? I'd look at how fast the industrial chain saws of similar type run.

A bike engine is not a bad idea... I've seen them powering a lot of things in asia. Some modern 4 cyl 4 strokes are running up to 20,000rpm now (!). Trouble is you wont be able to turn them sideways. Vertical isn't practical for most log lengths... but its nice when you can manage it

Shaun