Chipper Anyone use a PTO chipper?

[smfcpacfp]

I have the Wallenstein BX42 and have used it probably for 52 hours with no problems.

Like anything else there are a few tricks to avoid problems. We do exclusively softwoods.

Kubota B3030 HSDC snowblowing Jan 2012 (HD) - YouTube

 

[nspec]

You typically slow down the engine before disengaging a pto because a lot of tractors have a pto brake and this avoids smoking it.

 

[greg_g]

You typically slow down the engine before disengaging a pto because a lot of tractors have a pto brake and this avoids smoking it.

Might that not be an argument to use an over-running coupler (ORC) when running a heavy chipper with a PTO-brake equipped tractor?

//greg//

 

[DeeDubya]

I throttle back with the PTO engaged because it helps slow the flywheel much more quickly. No I don't just jerk back on the throttle. Common sense would tell you to throttle back slowly (within reason). Otherwise it can take my 8" chipper some time to wind down and the worst thing you can do is start to drive with the flywheel still spinning. It's a big gyro and moving the machine, especially a sharp turn will put a strain on the bearings.

 

[RoyJackson]

While I agree totally about starting/ engaging the PTO in near idle and then coming up to 540 rpm I have never understood the theory about shutdown.

nspec and DeeDubya wrote the answers I would have...

Two additions:
1) All of my tractors have had mechanical actuation of the PTO. Any engagment or disengagement at speed (remember, the PTO is turning at 540...but the input shaft may be turning considerably faster (engine RPM being 2500 RPM or there abouts). I can see no way engaging, or disengaging would not put a shock load on the tractor transmission. The higher the speed, the greater the load...
2) An implement that runs at high speed combined with high inertia (rotary cutter) will take a while to spin down, even if disengaging at idle. Disengaging at a higher RPM would extend that spin down time.

 

[bironacad]

I have a Wallenstien .

Ya wet cedar branches clog it up, lol I need something to clean out the jammed bits I have seen it somewhere here in the threads. Anyone got a picture?

 

[grsthegreat]

While I agree totally about starting/ engaging the PTO in near idle and then coming up to 540 rpm I have never understood the theory about shutdown. With a 200+ pound flywheel the mass inertia will push the PTO pretty hard on throttle back. I always thought it better to disengage then go to idle so as to avoid this issue. Nothing in the manual addresses this issue. Why do you believe it is better to disengage only after idling down with the mass inertia pushing it the whole way. A really massive brush cutter isn't as big inertia wise but it seems to push the PTO as well. I changed my technique after listening to the pto while doing it the old way.
Willing to learn why you do it your way.

By the way when I got the chipper the JD tech said to do start up at 540 and feather the pto clutch by engage/disengaging multiple times to slowly bring the flywheel up to speed. I immediately disregarded his advice as cycling the pto 5-10 times in a short period seemed really stupid to me.

thats why i use a over-running clutch on my chipper. It freewheels when disengaged.

 

[DB24]

Thanks for all the comments and advise regarding my question on the possibility of PTO clutch damage when starting and stopping a chipper due to the high inertial mass.

The use of a PTO shaft with over-run clutch certainly sounds like a very good idea to avoid any possibility of over stressing the PTO brake on disengagement. (My tractor has electro-hydraulic PTO clutch operation and you cannot therefore pause with both the PTO clutch and PTO brake disengaged, unlike manual systems where the lever can be held half way....)

 

[grsthegreat]

I just looked at the over running clutch as cheap insurance. Its pretty inexpensive and since it takes about 2-3 minutes for my chipper to spin down, anything that eliminated parts in the tractor from spinning during this time has to be beneficial.

 

[BethesdaEC]

I just looked at the over running clutch as cheap insurance. Its pretty inexpensive and since it takes about 2-3 minutes for my chipper to spin down, anything that eliminated parts in the tractor from spinning during this time has to be beneficial.

Stopping the disk is almost nothing for a brake, and if the overrun clutch lets it run for minutes you would have to wait a long time before you could open the housing to clear a clog. If there is no drama starting the disk, then brake should have no problem stopping it. Car brakes can last for 50K to 100K or more and they experience a lot more stress than a PTO brake.

Here is a question, has anyone worn out a PTO brake yet?