Homemade Chainsaw Mill

Big J · January 5, 2014

That LM2 does look a cracking bit of kit, you sound chuffed with it. Do you find you get any band wander on it at all?!

You can get a bit of band wander if you are trying to push a blunt band on past it's best. I was cutting some fairly hard, dry(ish) Elm a couple of days ago and whilst it was cutting flat, you could hear the motor starting to work harder. Cut rate was also down - in fairness to the band, it had cut 130 cubic foot of 1.25-2 inch stock (sycamore and elm). Took it off, new band on and my labourer couldn't keep up with the boards coming off. On a sharp band you run out of power (38hp) before it will wander.

Alec - quite agree, would put you in a class of one with no competition for economically milling 5ft butts.

Bella - not sure that much power is necessary! My experience with chainsaw milling is such that cutting speed increases exponentially with power. 8hp isn't twice the cut rate of 4hp, it's more like 5 times. My hope is that 15hp of hydraulic power (huge amounts of torque) will result in 4-5 times the cut rate of my Stihl 088, turning 15 minute cuts (which 18ft of sweet chestnut at 42 inches would be, averaging out the three cuts between sharpenings) into 3-4 minute cuts.

Can anyone find a motor and power pack to do that?

agrimog · January 6, 2014

hydraulics are a strange thing, to get the high flow rates required to get a motor spinning fast enough for the chainsaw, the pressure goes down, your starting to look at large class 3 pumps, and these need big power to run them, possibly something like a small car diesel engine, with a couple of pumps on the back, one for saw, one for ancillarys, your then into big wieghts and lack of portability. Ive looked into the various hydraulic options and a saw assembly from a harvester head is prohibitivly expensive compared to other options ( precision built plunger type motor with epicyclic gear box and bar mount and tensioner all built into one unit), makes a bandsaw seem cheap

treequip · January 6, 2014

Managed to find some specs for a hydraulic saw motor on the net for forestry harvester,, they run up to 10000 rpm ,, require 180 -200 litres a min dependent on sprocket size, and min operating pressure of 220 bar to 280 max

the saw motor also seems to control the ram which moves saw through the log ,,I wouldnt like to buy one thats for sure ,,anybody got an idea of price ???

My big hydraulic power pack for my sawmill is a fordson major industrial engine ,, and the pump produces about 90 litres and about 100 bar ,,

i think portability just went out the window as i think it would probs need a 80 hp engine to run a motor like that,,

The reason that motor uses that amount of oil is because they have that amount available on the carrier, you can do it with less if you use a standard low speed high torque motor and gear/belt drive the sprocket to get a respectable chain speed.

With that system you could run a mobile setup on a JCB beaver power pack, or similar

It will be slower than the harvester motor option but you have less power available and less in means less out.

tcfengineering · January 6, 2014

We would custom make this kind of thing at the right price. Everything already exists to do the job, if you look at Holtec crosscut saws in commercial sawmills, they have every you describe, but working vertically in a cross cut scenario. I have repaired, installed and commisioned a few of these, and they are a simple thing. Wouldnt be too hard to use this type of technology and make it into a large slabbing mill.

Cost is another issue, I expect that it would not be a cheap item, but this would depend on the spec you drew up for it.

Big J · January 6, 2014

We would custom make this kind of thing at the right price. Everything already exists to do the job, if you look at Holtec crosscut saws in commercial sawmills, they have every you describe, but working vertically in a cross cut scenario. I have repaired, installed and commisioned a few of these, and they are a simple thing. Wouldnt be too hard to use this type of technology and make it into a large slabbing mill.

Cost is another issue, I expect that it would not be a cheap item, but this would depend on the spec you drew up for it.

From my point of view, I wouldn't really want to go beyond a 60" bar. That would give me a 52 inch cut, which is frankly enough. Handling of boards becomes a huge PITA.

Spec for me would be :

52" throat horizontally, 30" throat vertically if possible (makes is a very useful machine for halving and quartering very large logs to be further sawn on the band mill).

Mill could be manually winched through the log so no powered drive required.

Approximately 15HP required.

Any proposal or even ball park figure would be superb.

tcfengineering · January 6, 2014

Do you envisage that this unit is setup in situ over the log like a lucas mill or would you be bringing the timber to the mill ?

Big J · January 6, 2014

I'd like it to be pretty similar to the Alaskan mill, requiring a flat surface for the first cut. I reckon it would be quicker to set up and more flexible to cut around burrs and the like. Static power pack, chainsaw mill moving up and down the log like the Alaskan mill.