How much Hp for a chainsaw mill

[BobL]

As in Bobl's illustration, torque doesn't change: torque is measured in pound-feet. You will get the same number of pound-feet whether r=1 foot and F=2 pounds or r= 2 feet and F= 1 pound. Horsepower will be the same also if the rpm stays the same.

The force available to the cutter will be reduced as you gear up the chain speed, but if you start with a 14 hp engine, should still be more than adequate for a mill. Of course there will be friction losses in the power transmission to the chain cutter.

Nailed it!

It's common to confuse force/power/torque especially on the internet

 

[KiwiBro]

This is also a useful document, for both your slabber and processor builds, Mr Mudd:

http://www.oregonproducts.com/pdf/harvester/MechanicalHarvesting_2005.pdf

It offers a few reference points that combined with the experience of millers will be worth knowing. I'd also suggest talking with Lucas or Peterson sawmill reps about how they spec and set-up their dedicated slabbers.

 

[muddstopper]

Actually, I have already saved the mechanical harvesting pdf file. Good reference material, I have read thru it several times.

 

[BobL]

Imteresting to see they rakers are as low as 0.070 pm some of those harvester chains

 

[muddstopper]

With those low rakers, you better have some power pulling the chain.

 

[BobL]

With those low rakers, you better have some power pulling the chain.

My initial thoughts were 0.070" rakers on 3/4" chain equates to a raker angle 8º which is not that special. I think it was Mtngun (a longtime member of this forum) who was using 9ª raker angles on 20" diameter wood with his 660 at altitude! and I have used 7.5º on Aussie hardwood with my 880 without much problem.

However, 3/4" chain cutter-raker spacing is twice that of 3/8 chain so the average size of the chip generated will be at least 2 maybe 3 times bigger. Unlike what most people think the chips are as much "pulled" as "cut" out of the kerf and it is this that that needs the power.

 

[olyman]

So increasing sprocket size reduces power, (force), at the saw. Which is what I thought. I may of used the wrong terms, but I knew the results.

look in the above posts,,for 820wards,,he has the engine mill I was thinking off..................

 

[mtfallsmikey]

My initial thoughts were 0.070" rakers on 3/4" chain equates to a raker angle 8º which is not that special. I think it was Mtngun (a longtime member of this forum) who was using 9ª raker angles on 20" diameter wood with his 660 at altitude! and I have used 7.5º on Aussie hardwood with my 880 without much problem.

However, 3/4" chain cutter-raker spacing is twice that of 3/8 chain so the average size of the chip generated will be at least 2 maybe 3 times bigger. Unlike what most people think the chips are as much "pulled" as "cut" out of the kerf and it is this that that needs the power.

Haven't been here for some time. Last time, you had sort of disappeared for a while, glad to see you back, I still apply some of your principles of chain sharpening.