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View Full Version : ATV Power Spreader – Earthway M21 Review:


dfischer
04-20-2007, 12:55 AM
I told a few on this site I’d share what I selected for a power spreader, why, and how it’s worked out. I selected the Earthway M21 for a few reasons:
* Their entry level model motor was weaker.
* I wanted built-in flow control (metering) stops. Entry level was open / closed.
* Price point, while high, was acceptable (this for residential use)
* It was size, shape appropriate.
* I expected Earthway’s port design adjustability would deliver even distribution.
* I felt this unit was most conducive to ATV mounting:
Highest AGL
Flow control set up for front mount.
Quick connect/disconnect came std.

Mounting:
As I knew I had to fabricate mounting and power anyway, I did not buy any optional mounting kits. This was probably wise. Since I needed to develop a reliable power harness and on/off switch to the front anyway, I added lights while I was @ it. Cable path routing, factory appearance, and reliability were all issues.

I’ve added some picture below to help any that might want to do the same. Be aware some of the brackets might look factory as all but one are painted JD green. Yes, I too don’t care for the plated square riser tubes, but I was limited to hardware store stock.

Results:
Pluses +
* Distribution is very even.
* Seems to clean-up well
* Motor seems quiet and powerfull.

Minuses, in order:
* The flow on/off jams open. This, as you can imagine, is flatly unacceptable.
* When it jams the cable mechanism often jumps it’s pulley system.
* Unit lacks slope at the bottom 6”, leaves ¼ bag leftover.
* The units motor is wired color coordinated backwards.

Conclusions:
*My thoughts on appropriate design for ease of ZTR mounting proved correct.
*My hope for even distribution has been born out.
*The unreliable flow shut-off mechanism is unacceptable.

Recommendations:
Pass. It can be made to be better, and I’m confident I can improve things enough, but it will take time. For $300 plus the many hours I spend deciding how to best mount and wire this thing, I deserved a better designed product. Sadly, I know of no other unit at this price point w/a similar combination of mounting options.

Final thoughts:
I will update this should Earthway have something insightfull to say about the jamming.

vegomatic40
04-20-2007, 09:59 AM
How do you govern application speed with a Hydrostat? Has always been my main objection to using this type of set-up. Sounds like a nightmare to calibrate.

dfischer
04-20-2007, 10:34 AM
A fair question, and one I'd considered too. But it seems to be a non-issue in practice. I do keep the power/rpm down to perhaps 1/2, and that seems to help minimize control sensitivity. I found I was pretty well on the nuts for recommended coverage. Mind you, I applied at a speed lots slower then I mow at..

Still, some coverage variance will occur. It's just a speed/convenience trade-off that must be evaluated. On the other hand, with so much faster application (wider swath, higher transit speed) and reduced reloading, I think any density variance's will be more then offset by reduced overlap and voids.

ymmv, and of course I'd been using a pretty poor walk-behind broadcast spreader. A pro walking and using spyker might do a better job then me no matter what.

americanlawn
04-20-2007, 11:13 PM
Spyker. You will NOT be sorry. Good luck.

dfischer
04-21-2007, 05:57 AM
I worked some on the jam tendencies today. There are 3 design issues compounding the problem:

1: The cable was binding coming in to and off of the pulley. It was fairly easy to fix. Look @ pics. The cable was binding (you could actually feel the cable twists rubbing) against the pulley coming from the control plate to the pulley. It was roughly 15 degree too far to the right. In this pic I've bent it inward (to the left) and as you can see it's now feeding onto the pulley nicely. But it was still binding as it left the pulley (headed to the meter plate and subsquent rope, down in this pic). Another, 10 degree twist, this time counter-clockwise, (in this pic) resolved that problem. As you can see it now feeds pretty straight on and off the pulley. However:

2: Looking at the pics, you'll note the pulley is below (really above, but the unit is upside down in the pic) the plane the flow control mechanism operates on. Thats right race fans, every time you open the darn thing you're exerting a bending force on the control plate. Look a pic #2 and you'll see the gouge in the plastic already forming from one of the phillips head screws in the mechanism.

However, we reach the end of my willingness to correct the design until Earthway and I speak. A simple enough fix really, the piece of metal I've bent to correct the pulley feed should have been installed angled on the vertical plane (and made perhaps 1" longer) enough so the cable fed in on the same horizontal plane the flow control operates on.

#3: I fear the actual problem is fertilizer granules binding between the control plate and base of the hopper (At the flow opening). But perhaps removing the bending forces I've identified will help reduce this problem.

dfischer
04-23-2007, 02:53 PM
Earthway has checked in. They'll be looking at into this. Two thoughts:

* Good for them! Mfg interest can't help but be good for the product and suggests solid support should I need it.

* Perhaps we'll see an update in the pulley mounting arm. Won't take much design change to vastly improve it.
- Longer and angled to get the feed on the correct plane
- Twisted and bent to a position that allows proper cable path
- A "retainer" bracket added to keep the cable on the pulley when the shutoff action hangs.

I'll share what I learn.

dan

tremor
04-24-2007, 03:15 AM
That flat aluminum bar the pulley is mounted to is an engineering blunder. By design it simply MUST flex under load. That mount would need to be cast or extruded out of channel to work properly (not flex) but the pulley itself looks weak too.

The cable is coming in from the wrong angle so the condition you describe is predictable. I'm shocked any manufacturer would go to market with a contraption like that.

dfischer
04-24-2007, 01:30 PM
Its a steel arm and the load is across it's span. In practice it has no apparant flex to it, but then it's taking a load measured in ounces. It's pulling against a spring, yes?

I wasn't too happy w/the pulley at first as it had a tendency to wobble. I feared it would round itself out. Note I've added a washer to the side to reduce the clearance.

They do make a heavier duty model, the M40, but its closer to $800.

I do kinda wonder how any engineer let that arm get by.

dfischer
07-20-2007, 01:55 PM
More updates, more negative (mostly) feedback:

The sticking of the shut-off has been minimized by doubling up the springs. A bit ugly, and certainly no replacement for proper engineering, but it's by and large working. However:

In more use I've found the hopper design to be so deeply flawed as to be insurmountable. It's so wide of base w/so extensive a flat plate on the bottom that in practice it generally STOPS SPREADING. A few nudges, kicks, sudden stop starts, or whatever will force whatever material to shift enough to start spreading again, but unless you're driving over corn rows it's going to plug repeatedly.

I've attached the included cotter pin as an agitator. No help. I've built my own larger agitator. No help, but now reduced spread (motor only has so much power).

If the unit is full (like 150lbs of content) it will spread fine. Get down to 60lbs of material and it stops flowing constantly, and how wants to have a bag and a half of leftover material at every use?

At present I've cut styrofoam inserts out that substantially reduce the internal dimensions of the unit and made play-dough molds for the bottom to create a tapered bottom instead of a flat floor. Now it flows properly, but what a hassle and mess.

And, as I've mentioned before, I'm fundamentally re-thinking the entire product to make it work. Nor has Eathway followed up w/any solutions. I've placed calls in again and we'll see, but at this point I'm going to ask them to get me out of the product.

As a side comment, clearly this flow issue is why so many other designs are round tapered cylinders w/a funnel on the bottom... Those design would seem to deliver proper flow, albeit at the expense (in those I've seen) of outboard motors).

As before, if Earthway delivers I'll let you all know.

Finally, a sad but funny comment:

At least right now, if the shut-off jams open I don't need to fear burning up my lawn by stopped to fix it. If I spread for a little bit more it will stop flowing soon enough all by itself.

Sigh...

dfischer
07-20-2007, 02:40 PM
Ah, so sad. I've spoken with Earthway customer service. Such nice people, with such a unique niche product, that is so badly screwed up and so easy to have fixed. Well, fixing the arm is a simple design change. Fixing a poor hopper design is not gonna be cheap, but you'd think they'd have a hopper with better flow designs in some part of their line.

Anyway, they've had me leave a voice mail w/a VP of marketing, and we'll see what he does or can do to resolve things.

heritage
07-20-2007, 02:45 PM
Dfischer,

Perhaps you could buy a can of "STUFF" foam. It becomes hard and smooth after it sets up. You could make a Funnel form, the shape you want, then spray tube under form until full. Then in a day you could sand to perfection. GREAT STUFF foam. Plumbers use this to fill voids between walls and pipes. Good Stuff LOL

Great job testing,

Pete D.

dfischer
07-20-2007, 03:30 PM
Yep, got lots of it. I don't know how well it will hold, and of course it's a more permanent modification. I've resisted doing anything that would alter it's state as I've wanted to protect my ability to return it.

Still, as you say, it can be shaped easily and fills voids well. If I was to keep it I'd probably use that, hobby putty, or perhaps even make a fiberglass insert. But at present I'm more inclined to bail and start over.

Still, thanks for the idea, and maybe EW will come through...

dfischer
07-20-2007, 03:39 PM
Yep, got lots of it. I don't know how well it will hold, and of course it's a more permanent modification. I've resisted doing anything that would alter it's state as I've wanted to protect my ability to return it.

Still, as you say, it can be shaped easily and fills voids well. If I was to keep it I'd probably use that, hobby putty, or perhaps even make a fiberglass insert. But at present I'm more inclined to bail and start over.

Still, thanks for the idea, and may EW will come through...

dfischer
07-20-2007, 04:32 PM
Wow, a double post. Hard to do... I musta really screwed up...

Just had an insightfull and hopeful conversation w/Earthway. I'm at least encouraged that this unit could still be become the best solution for Z owners. It appears the whole pulley arm re-design is, as hoped, an easy fix. I'm guessing that'll become a reality.

The flow stoppage seems to be known in the industry as "bridging". I shoulda known. Anyway, doings are afoot and it's just possible this too can be fixed. If so, we could have a good solution yet.

We'll see, and it will be quite some time again before we know, but I'll share once again when more answers are known.

dfischer
04-12-2010, 09:48 PM
bump, since many look at these this time of year.

Take my advice. Buy something else. I fight with this thing every year. I've finally built a sheet metal ramp to take out all the lips and steepen the slope, then backfilled it with great stuff. it usually doesn't jam now. Too often :(

So, if you want to spend a few years of your life here you go. Otherwise look for something metal with VERY steep sides and a strong motor.

And support? forget it. They called me once over several years of calls for help.