Woodmaxx 8H Chipper - First impressions

[KY Gun Geek]

Did my research and settled on a WoodMaxx 8h

Arrived crated up as promised, assembly was pretty straight forward. Nothing terribly remarkable.

There are some threads here discussion issues with the feed speed control. Here's what I measured on my new chipper:

Setting Speed(RPM) % of max
1 0 0
2 0 0
2.5 11.7 25 (Jerky movement)
3.0 23 50
3.5 46 100
4.0 46 100
5.0 46 100
|
|
10 46 100


I think this pretty much agrees with what others have seen in the posts below. I emailed Woodmaxx about this issue before I purchased and they didn't comment (they did say they appreciated the links to these posts, though).

I then tried to see if this speed issue actually matters (several posts say they leave it wide open and don't have a problem). Well, we stuck a 6" cherry branch into this thing at full speed and guess what - it just about stalled the tractor (85hp jd running in EPTO mode so PTO hp is 45 or 50). This also clogged the system and since it was 40 degrees and raining, we retired to the shop to unclog. We will try again at a slower setting and see what we get.

My plan from here is use it a little to see if it will chip bigger stuff at the slower setting.

As outfitted with the valve, you really have 2 speeds - 50% and 100%. The adjustment is not very fine so it is difficult to get anything less than the 50% Of course the ideal would be to have each setting add 10% to the speed. This would allow you to fine tune. But, in practice that may not really be necessary - slow and fast might be all you need. Clearly, however, you MUST adjust the speed to use on larger stuff. The adjustment and valve seems to be a bit fragile for this kind of equipment and a little slow to change - perhaps a paddle that selects 1 of 3 or 4 speeds - slow, med, fast, warp...

This thing eats smaller stuff nicely at full speed and seems to be a well built piece of equipment.

At this point only 2 issues - the speed as discussed above and what seems to me to be a strange stop bar design. The bar rests right on top of the chute and if do the natural hit on the bar (a straight push away and a little up from you) it won't do anything. You have to push it at a down angle down a little. When you do, it reverses the feed even though the bar says it will stop. If you are ginger ("fiddly bits" as I saw a Brit guy working on a transmission on TV say), you can indeed cause the feed to stop, but in a panic, you will not be ginger, so it is going to reverse. Not the expected behavior, but I'm not sure it is unsafe. I'm still trying figure out if we assembled something wrong - Fiddly bits.

https://www.tractorbynet.com/forums/attachments/377764-woodmaxx-wm-8h-feed-problem.html

https://www.tractorbynet.com/forums/hydraulics/377635-hydraulic-motor-flow-valve.html

 

[oosik]

Ok - just as a comparison. I have a Wallenstein BX62S - manual feed. This summer I removed and chipped the remaining apple trees in my orchard. They all died two or three years ago and were as hard as obsidian glass. All but one of the tree trunks were much larger than 6 1/2" that the Wally would take - so I split them prior to chipping. They gave the Wally a good workout but went thru with no difficulties.

Anyhow - here come the 6" trunk - hard as obsidian glass. It got about 3/4 of the way thru chipping and I heard a - "twing" sound - tractor rpm speeds right up to 2150 - PTO speed. I had just blown the first shear pin on the Wally. Its five years old - has been used ONLY to chip Ponderosa pine and never - previously - blown a shear pin.

The Wally pulled the apple trunk in too hard, too fast and choked itself. Its the one time that hydraulic feed would have helped. I could have run the "in-feed" at about half speed and prevented this choking action.

My tractor is - - 2009 Kubota M6040 with 64 engine hp - - 57 PTO hp.

 

[sea2summit]

I then tried to see if this speed issue actually matters (several posts say they leave it wide open and don't have a problem). Well, we stuck a 6" cherry branch into this thing at full speed and guess what - it just about stalled the tractor (85hp jd running in EPTO mode so PTO hp is 45 or 50). This also clogged the system and since it was 40 degrees and raining, we retired to the shop to unclog. We will try again at a slower setting and see what we get.

I believe the rule of thumb is 10PTO HP to 1" of material so bogging down at 6" for 50 PTO HP would seem about right. I just put a deposit in on a MX-9900 and have no other experience so my opinion is worth what you paid for it

 

[cdb2]

Thanks for posting your impressions. We also just bought the Woodmaxx 8H and did the first few hours of chipping over the last three or four days. My impressions pretty much match your own. The speed control on ours works about as well. We're running it on a 55HP tractor that I think is rated at about 42 PTO HP and did not have any issues bogging the chipper down running stuff up to about 5" but this was with cedar.

I don't think the stop bar design is unsafe, but it does seem to work the opposite of how I think it ought to. The only problem I ran into with the real gnarly branches is that once or twice a branch got hung up on the feed chute in such a way that it jammed the feed stop upwards into forward and was a bit difficult to force it down to reverse. If the feed bar worked opposite anything getting hung up would bump into reverse which would help to clear the hangup.

Oh, one other thing that's odd but pretty minor - with the bottom feet set up about half way so that the PTO matches our tractor, the rear chute support bar for storage can't touch the ground, it's about 3 inches short. I don't think it would work on anything but the lowest setting for the feet.

All in all we're happy with it so far, the quality seems fair for the price and it's doing the job so far.

 

[747driver]

Have had our WM 8H almost 2 years. Really like it as it does what I need. Use it to grind up trees and brush up to 4"....anything bigger is for fire wood. Got 30 hours out of the original blades, then had to change to the other side. When you see the chips starting to get stringy and the chute plugging up its time to swap blades. Need to order a spare set of blades though.

 

[oosik]

Here is a wild difference between chipping hard material and soft. My Wallenstein BX62S is five years old. Since I average right around 25 hours chipping every spring - its got somewhere around 125 hours on it. I'm still on the same side of the reversible chipper blades. No noticeable difference between the way it chipped this spring and the spring of 2013 when I bought it.

I chip green pine trees. About the only thing softer would be bananas.

 

[ericm979]

Looks like you found my threads. The Brand replacement valve is working well after I adjusted the relief. Totally plug and play. It's too bad they don't ship with that, or a chinese version, as it makes the chipper easier to operate especially when you have variable size material and need to change feed speeds. The safety bar on mine works like you describe. I figure that it's ok if it puts the rollers in reverse.

I'm getting 20 hours per side on the blades, but I have been chipping a lot of dead brush which is hard on the blades. When they dull the chips get stringy. That's the only time I have clogged the chute.