what size engine do i need to drive sawbench with 30 inch blade?

[startinghandle]

I have sawbench with 30 inch blade which I want to mount on frame with axle, I have a perkins engine which could be used but it is 25 HP which makes it too powerful!! it will never be under heavy load and could glaze up so I have been thinking of fitting a lister so that it will have to be put under load and blow out black smoke which will keep it in good condition
what size engine do I need and  I live in mid wales
also the blade should be running at about 600 RPM

[Samo]

Interesting problem, I don't think a CS Lister is up for this, they spin too slow at 650 rpm. I would think you need a faster spinning engine with reduction gearing to drive that blade.  I've seen Lucas Mills with 30 hp engines for around 8.5" cut, so I'm not so sure you're Perkins is such a bad fit. But maybe Australian hardwood takes a bit more grunt

[mikenash]

IHMO it depends entirely on what work the saw has to do

I have seen a 5HP CS/1 running a big firewood saw of similar dimensions locally for years.  Because the saw is doing cut after cut after cut, with a moment between each one,  and because the operator controls the "feed speed", the CS handles that just fine

In various sawmills I have worked on there have been #2 or #3 saws around that size, working as secondary-cut saws behind the big breaking-down saw - typically these have had 40 - 60 Hp motors or similar, as the performance of the saw depends on the rotational speed remaining constant despite varying loads and feed speeds.

If you are running any kind of production sawmill off of a diesel motor this is just a recipe for slow bankruptcy - IMHO

Because of the big flywheel, the CS will make a good firewood saw motor - as long as you know what you are doing with setting-and-sharpening the teeth, and as long as you can control the feed speed manually.

Just my $0.02

Cheers

[38ac]

Depends on what you will be sawing on the bench, how fast you expect it to preform and how well you maintain the blade. We dont see what you guys call a saw bench here but we use a somewhat different machine we call a Buzz saw or cordwood saw.
a 6HP Listeroid runs my saw in fine style when running the wood we typically run. We cut large pieces with a chain saw. Operating the mandrel at the correct RPM  has almost zero to due with how fast the engine runs and everything to do with using the correct sized pulleys.  I used to be able to direct llnk videos here but that function has disappeared?? However if you follow the link provided you will see my saw in operation and you will better be able to judge if your 6/1 will suit your needs.

https://youtu.be/IYYh5Rx6Eh8

[mike90045]

depends on how fast you feed logs into the sawblade

[vdubnut62]

The glazing thing is real Glort, the Cummins in my truck glazed due to cold, short runs, and underloading.
It took a blown water hose induced 220 degree full throttle run up the Interstate pulling a 32 ft 5th wheel camper to start  breaking the glaze.   I guess I was lucky the glaze was all that let go!
Ron.