Jack,
Reviving this old thread and wondering what your resolution was with the wobble? Please provide for us. Thanks.
The wobble wasn't actually the biggest problem with the machine. It's a MacKissic TPH122, and the main issue is that one of the bolts holding the knife to the flywheel worked its way loose very early on. The protruding bolt head quickly chewed up the wear plate that controls the depth of the cut, and damaged the threads in the flywheel that hold the bolt. Looked to me that no Loctite was used during assembly. Clearly threadlocker is supposed to be there since the instructions on changing out the knife tell you to apply heat to "unlock" the Loctite. That was a warranty issue, but coupled with the wobble I was not a happy customer.
But MacKissic handled it well. They asked me if I wanted new parts, or a whole new unit. I opted for the latter, and the new one works great. It was a bit of a hassle to re-crate the defective unit and arrange delivery of the replacement, since I do value my time. But overall, I'd recommend the vendor and their product.
So to comment on an above post: I did buy American, and while I managed to get a lemon, the customer service was good, as is chipper/shredder.
It will devour 3.5" limbs as advertised, and that's about all my little BX1870 has power to chew. Which is fine by me, as anything over 3" goes in the woodstove.
My main goal in purchasing was to 1) Have something I could run off the PTO on my then-new toy, er, tractor (which is mostly a mower/firewood mover/motorized wheelbarrow); and 2) Have an ample supply of woodchips for mulch and trail maintenance. My only disappointment is how many little saplings and limbs it takes to get decent mulch pile. But that's not the machine's fault--it gobbles stuff up just fine, and the hammermill is great at swallowing the miscellaneous little trash that won't go down the limb hopper.