Thread: Building a Mulch Trailer

Construction has been interrupted by on-snow activities, but I'm now back on board.

Next thing to sort out was putting the auger together, and sorting out drive shafts and bearings. I ordered some 25mm pillow-block self-aligning bearings. I thought I had some 25mm round bar, but when I went to try and insert it, I discovered it was, in fact 25.4mm. No problem - my neighbour is a retired fitter and turner, has a couple of lathes and a milling machine - he'll sort this out no problem.

Problem was, he's on holiday.

What to do? I only need to take off 0.2mm - how hard can that be? So I build me a lathe:

Lathe.jpg

The process was not as fast or as easy as imagined, but evetually the the stupid shaft fitted through the damn bearing.


The motor coupling wanted a 32mm dia shaft, so I needed to bush up my now precisely-turned 25.000 shaft. First some top shelf bushing stock:
Bushing Stock.jpg

Then with some precision work with the bandsaw, a vice and a hammer I had this beauty:
Bush.jpg

Put it all together to get this:
Bearing and Coupling.jpg

I carefully measured the runout by checking if the coupling hit the bench when spun. It didn't.

I welded all my Ebay augers onto the gal pipe shaft - it all looked quite convincing when done, not that I have any pics to prove it.

Then came the hydraulics. This was my first attempt:
Hydraulics 1.jpg

The I backed up the tractor and discovered the lines weren't long enough to plug in, so version 2, hydraulics on a stick:
Hydraulics 2.jpg

You can see the mounting of the oil-powered motor in the background.

With that mess all together, time for testing.

1 bucket of mulch, neatly ejected:
Mulch Out.jpg

Then 5 buckets or mulch in the hopper:
Hopper with Mulch.jpg

Which isn't that much, but that's where the problems started. With the relief valve set to cut out at 40 bar, the auger wouldn't move. Wound up to 80 bar and it'd move a bit, then the coupling slipped. Tightening up the coupling and tweaking the auger back and forth got it spinning at about 120 bar - once moving the pressure dropped back to about 20-30 bar.

My initial thought is that the problem is the weight of the mulch pushing the auger against the metal floor, so one solution would be to add intermediate supports to the auger to hold it up so it doesn't touch the metal

Once the auger got going, it emptied the 5-bucket load pretty efficiently, although more room is needed at the back to allow the mulch to exit.

I then loaded 10 buckets in. Getting the auger spinning again required a bit of to and fro, but eventually it started doing its thing. The next problem was a cave-like void forming over the auger, which jerking the trailer about didn't fix. In the end it required a lot of poking with a stick to get it all to collapse onto the auger. I'll look at sorting out the stalled auger issue first before getting on to this one....

Hi Rusty
I'm assuming you are using 205 housings as you could've got imperial bearings to suit.
UC 205-16 they are, or used to be
Not that it helps now lol

Phil

Originally Posted by Steamwhisperer

I'm assuming you are using 205 housings as you could've got imperial bearings to suit.

I think you're right about that - it didn't even occur to me, though I imagine inserting a self-aligning bearing into a housing requires some kind of magic?

Having, I think, identified a problem with having the auger edges resting against the steel floor, my solution is to support the auger at a couple of points along its length. That requires fitting bearings in a few places - the auger is 3m long, so adding an intermediate bearing at the 1 and 2 metre point seems to make sense. Given, when spinning, the radial forces aren't significant, and there's no requirement for runout, I decided fitting a plastic "guide" might do the job. So I sourced the components:
Bearing parts.jpg

Put together a prototype:
Bearing fitted.jpg

Cut a chunk of flight out where the bearing is going:
Flight Cut.jpg

And fit it in place:
Bearing in Place.jpg

The bolts are only there for illustration - I'll be using M10 threaded rod going through the bottom and sides of the floor to hold it in place, the threaded rod allowing adjustment to ensure the bearings are axial.