pto powered bandsaw ?

[Renze]

i have seen plenty of home made bandsaws on YouTube, made with some frame, a rolling saw portal, and 2 old car tires to drive the saw band around... the log stays in place and the bandsaw portal moves through the log.
But they are all low power, gas or electric powered...

Older circular sawmills have a stationary blade, and roll the log on a bed through the sawblade. The big drawback is that it needs double the length of bed.

Does anyone have an idea how to power a moving bandsaw head with a stationary tractor PTO drive ? the idea is to cut costs, so hydraulic is no option...

 

[PILOON]

Don't think what you want to do is possible.

Sure, a PTO generator could drive an electric motor but that would end up costing more than hydraulics.

Forget any kind of flex drive due to power required.

OK, I could see a long PTO shaft doing the job but that would be cumbersome and prone to trouble.(and very dangereous) as the tractor would need to be a fair distance from the sawmill in order for the shaft to slide in and out to reach both ends of the mill.
With a long shaft unsupported in middle it would probably whip about and kill the operator.
Also the carriage would probably fall off the tracks as it relies on the engine weight to keep it 'on track'.

Your best bet is still a gas engine.

Locally sawmills are offered fo about $4000.CDN with 12 hp engine.
While considered underpowered they still do cut wood.

Why not consider a chainsaw mill? basically a saw clamped to a channel that follows a 2 x 4 as a guide.

 

[BHD]

use a 90 degree gear box and set the head up stationary and move the log on a carraige. like in the circular saw units, I would put the vertically instead of hormonally, most used some type of cable system that would power the log carraige system,

 

[Brad_Blazer]

You could use one of these to transmit power but the length is pretty limited.
http://www.nookindustries.com/pdf/NookSpline.pdf
Otherwise drive the tractor alongside the rails to power the saw and move it.

My brother hired a sawyer who had a Woodmiser with a 40hp turbo diesel. It wasn't underpowered. Lots of hydraulics and good control with the operator on a seat that moved with the carriage.

Brad

Edit : It's Wood Mizer. The one I saw was similar to this: YouTube - Wood-mizer Portable Sawmills - LT40 Super Hydraulic

 

[dfkrug]

But they are all low power, gas or electric powered...

One day, I would like to build one with the moving carriage. I have collected
the motor (and spares) I want to use: water cooled, 2-cyl Honda CX500
engine @ about 50hp. Compact, powerful, cheap.

 

[Renze]

You could use one of these to transmit power but the length is pretty limited.
http://www.nookindustries.com/pdf/NookSpline.pdf

I've been thinking in that direction too (instead of using a very, very long PTO shaft as suggested, use just the 6 meter PTO shaft with bearings on both ends, and use a 2 foot sliding outer shaft that moves along with the saw..

Problems i see in that setup, is that the PTO shaft will whip around, and that it wont slide very long: If you dont grease it it wont, and if you do grease it, it will be covered in sawdust and wont slide either

But this nook spline gives a new perspective to that principle: I could use a big 200x200mm square tube as driveshaft, and make a collar around it rolling on several of those polyethylene hand pallet pumplift truck rollers to reduce the axial friction. The rollers have enclosed bearings so wont take up sawdust, and the axle (square tube) can remain bone dry, so it wont catch any sawdust.

Otherwise drive the tractor alongside the rails to power the saw and move it.

Ive been thinking about that too, it would be killing 2 flies in the same slap.. However the tractor will pull the saw portal off the rails... and i'd need to get on and off the tractor in order to load and unload logs, pick up the boards, etcetera...


Maybe i should just be statisfied with the 7.5 Hp (or was it 7.5 Kw ?) 3 phase electrical motor, i bought it 2 years ago for 15 Euro as a backup for our irrigation pump...
In the end it will be cheapest, and the continous torque of a 10 hp electrical motor will outperform a 15 or 20 hp gas engine any day....

Would it really make a difference, is power the limiting factor, or the saw band itself ?

 

[Brad_Blazer]

The more I think about it the more it makes sense to have a dedicated motor that travels with the bandsaw. If you want more power just mount a bigger motor from some junk vehicle. A driven carraige is probably needed to make use of more than 10 - 15 hp.

That electric motor should be plenty. Here is an example of an electric band saw head:
Sawunits

You'll need to have a way for the power cord to traverse. The Wood Mizer video shows a fancy cable carrier.

 

[Paddy]

Renze,

I built a band saw saw mill 25 years ago. Very simple 8 Hp engine on a moving saw, stationary log. Worked good enough to build a 2500 sq-ft timber frame home. I mostly sqared logs to 8" x 8" 10' long. I used cast iron pullys. These were comercial types, 18" dia and with 3 or 4 groove V-belt. I bought a length of belt to make the rubber surface. The pullies were mounted on 1" dia keyed shaft, 16" long. I made one of the shafts, adjustable for tracking.

I don't remember all the details but, I know the limiting factor on my saw was the blade drifting up and down if I push it too fast. Could have been blade speed?

Patrick T

 

[SkunkWerX]

I would come off of the tractor's PTO with a pully/belt system.

This would accomplish two things:
1. ability to set proper band-blade speed.
2. reduce shock loads, nto worried about the tractor PTO, more the band-blade which might be more subject to fatigue and breakage if driven directly.

You would have to stationary mount the blade power assembly, and use a guiderail or roller assembly carraige to move the wood through the blade.

 

[dfkrug]

I built a band saw saw mill 25 years ago. Very simple 8 Hp engine on a moving saw, stationary log. Worked good enough to build a 2500 sq-ft timber frame home. I mostly sqared logs to 8" x 8" 10' long. I used cast iron pullys. These were comercial types, 18" dia and with 3 or 4 groove V-belt. I bought a length of belt to make the rubber surface. The pullies were mounted on 1" dia keyed shaft, 16" long. I made one of the shafts, adjustable for tracking.

So the rubber belt went over the 18" pulleys to act as blade drive wheels?
Any reason you did not use automotive wheels/tires as seen in some of the
home-built units? Sounds like 18" pulleys woould be hard to come by.

Also, how wide was your bandsaw blade?