Author Topic: Centrifugal clutch for Woodmizer (Read 6357 times)

woodbeard · « **on:** October 20, 2007, 11:31:38 AM »

A few weeks ago, I started noticing a new pain in my right shoulder that got progressively worse. It was pretty obvious to me that it was/is a result of operating the clutch lever on my woodmizer, and would eventually result in permanent damage.
What was not so obvious was what to do about it. My mill is a '92 model, so the autoclutch package offered by WM would not fit, at least not without a good deal of rigging and tinkering.
So, I did some research and thinking, and found a centrifugal clutch that would fit on the shaft of the 24hp Honda I have on the mill.

The Honda motor has a 3 1/2" long shaft, which is the minimum that this clutch plus a pulley for the alternator belt will fit on. My old Onan had a 2 1/2" shaft, so this will not work for that motor if the mill has an alternator.
The other issue is that the pulley on the clutch is 4" diameter, and the original drive pulley was 3.5", So I found a 14" pulley for the bandwheel drive arbor to replace the 12.5" one inorder to keep the blade speed the same. This is the largest pulley that will fit in there, and even so, it required a little modification to the brake strap mount. The one on my mill had mounting holes for both the old style cotton strap, and for the newer metallic strap. I had to cut the part with the hole for the cotton strap off to give enough room to get the belt on. It is shown here without the strap.

Then, I got a throttle lever and cable like for a mower, and mounted it on the old clutch lever.

So far, it seems to be working well, but takes a bit of getting used to. I still need to do a bit of tweaking to get the brake strap back on, but once I do, it will still be available for use in those times when I really need the blade to stop immediately.

Tom · « **Reply #1 on:** October 20, 2007, 01:27:14 PM »

Glad to see you confronting the repititious movement injury head-on.

In the old manuals, one of the diagnosis' for a blade coming off was a mal-adjusted brake. If you start throwing blades, it might help to look at the brake strap, or its non-use.

That appears to be the same clutch that I had on my first baker. The pads are aluminum and will melt. What a mess. There are no instructions for inspection generally offered, but you should check those pads every now and again. You shouldn't have to do it too frequently unless you smoke it. There is a pad kit to repair it with that is a bit less expensive than buying a new clutch.

sawwood · « **Reply #2 on:** October 20, 2007, 06:08:51 PM »

Woodbeard where did you find that clutch at ? The one on JR Norwood is gitting bad
and i think it needs a better one then Norwood has, We have the Honda 20HP
motor.

Sawwood

woodbeard · « **Reply #3 on:** October 20, 2007, 07:17:21 PM »

SW: I got it direct from BLM industries, the manufacturer.
Noram is another brand.
Comet also makes them, but nothing heavy enough.
I'd hazard a guess that Norwood uses one of the first two.
Linn lumber sells one, and you can also get one thru Hud-son, and there's a guy on ebay that sells them too.
But I would call Norwood first and find out if it isn't just the same clutch you would get from any of the others.

Tom, thanks for the heads up on not letting the smoke out.

Time will tell how well this addresses the RMI issue for me. But it is a good first step. There are a lot of other things I need to change as well, mostly little things like not reaching across the log to crank the blade tension handle, etc. that all add up.

pineywoods · « **Reply #4 on:** October 20, 2007, 08:36:22 PM »

Hey folks, JP Green came up with a fix for this problem that works fine on any mill and is practically free. Do a search on jpclutch. It's there complete with pics.

shopteacher · « **Reply #5 on:** October 24, 2007, 05:30:06 PM »

Tried the search but came up empty handed. I would like to see it as I seem to be getting the ailment in the right shoulder. If anybody finds it please let me know where to locate it.

logwalker · « **Reply #6 on:** October 24, 2007, 07:28:24 PM »

How hard is it to retro fit the older lt40's? It seems to me that would be better than the centrifugal clutch. Joe

pineywoods · « **Reply #7 on:** October 24, 2007, 09:42:39 PM »

try here- link to jpgreen's jpclutch, not as good as autoclutch but sure helps.

http://www.forestryforum.com/board/index.php?topic=22216.msg315128#msg315128

woodbeard · « **Reply #8 on:** October 25, 2007, 07:29:48 AM »

JP's clutch spring will make the lever easier to operate, but it still involves the same repetitive motion. If you are already feeling the pain in your shoulder, this will not help.

Quote

How hard is it to retro fit the older lt40's? It seems to me that would be better than the centrifugal clutch. Joe

Best I can tell, it would involve welding on something to mount it on, and finding a place to put the switch. After that, it might be just a direct install, but hard to say for sure.

shopteacher · « **Reply #9 on:** October 25, 2007, 02:22:05 PM »

Thanks for the link Piney

Forestry Forum
Sponsored by: