Thanks for all that, Eric.
Our gearbox shaft doesn't have a spline, it has a key, and I will ensure
something locks the blade in place or I will build a mounting assembly which
fastens into the keyway onto which to attach the blade. Terry says he's got
the blade off the old lawn mower for me, I just haven't been out to take a
look at it yet. He says tightness of the bolt is all that kept the blade
from spinning on the mower shaft, but I know that's not sufficient for
mixing papercrete. I may ask the blacksmith we use to stop in and give his
opinion. He's a pretty sharp chap and could bang up what I need in his
forge . . . if the metal would be strong enough. I'll have to ask him.
I toyed with the idea of using the gyromower assembly, but it relies on
centrifical force to cut and I don't think that will work as well in a
solids populated liquid.
Mike McCain used a sluice gate type assembly and had to address it with a
sledge for it to do its job. The elephant snout will work for me if I use a
small car tire inner tube with a 3" hose connector at the end to which I'll
attach the pump's inlet hose. I'm pumping not dumping, so that should work
for my app.
ElfN, who is off to look at Eric's new pics.
----- Original Message -----
From: "Eric Randall" <eric@eric-randall.com>
>
> Hi Nori,
>
> I decided on a 5' 265 gallon tank. The 4' tank will certainly be
> easier to fill and manage, but obviously will require more
> batches. I'd recommend making your frame large enough to accommodate
> a 5' tank should you decide you want a bigger tank later, after
> you've got a sense of volume and mixing issues -- sounds like you'll
> be making quite a few batches, so tank size might make a big difference...
>
> Over this past weekend I finally attached a 4" Valterra gate valve to
> the bottom of my tank. I did some pursue the tire "elephant trunk"
> approach of
> http://www.makepapercrete.com/The-Papercrete-Tow-Mixer.html, but I
> wasn't happy with how it was coming together, and decided I really
> wanted more control of the output, which a gate valve gives me. I
> purchased the 4" gate valve over eBay for about $80. See "Eric's PTO
> Mixer Part 2" for a photo of the valve and the valve mounted. The
> 2x6 between the valve and the tank serves as a mounting flange. Note
> that I actually have a short section (~3") of 4" PVC sticking through
> the 2x6 -- it helped line up the valve to the tank, and just makes a
> better flange assembly. A PVC flange might have been nicer, but I
> couldn't find one, and this seemed like a very doable solution.
>
> As you can see from the photo, it dumps nicely into a
> wheelbarrow. My plan is to drill 3 or four 1/4" holes on the
> downside flange of the valve, allowing me to quickly bolt on
> different PVC elboes and lengths, for a de-watering process. With a
> 4" to 3" reducer, this type of setup could be ideal for connecting to
> a trash pump input. Just tilt the tank a bit so it all flows to the
> valve -- no need to pump up and over the edge, and easy to get
> everything out of the tank.
>
> After getting my valve installed, I noticed a gate valve setup on
> http://www.livinginpaper.com/mixers.htm -- a "slide ditch gate valve"
> -- essentially a gate valve but perhaps one more appropriate for
> papercrete. I encourage you to check this out. The challenge for me
> with my Valterra gate valve is that it is essentially a stainless
> plate that slides between two rubber gaskets. I'll have to make sure
> to clean it well after each use to keep it functioning properly. The
> "slide ditch gate valve" shown on Living In Paper looks like it would
> be more forgiving -- it also looks like you can get it in larger
> openings, possibly at more reasonable prices. I haven't checked out
> prices, but here is a starting link:
> http://www.allmetalssupply.com/waterman_gates.htm.
>
> I went to mix my first batch over the weekend and discovered I needed
> to do some more work. Essentially the paper would stall the
> blade. So today I had my 12-spline carrier hub welded to a 1/4"
> 4"x4" plate with two 5/16" holes for bolting on the lawnmower
> blade. This is similar to what a rotary cutter does-- they have a
> "dishpan" assembly, which is essentially a 12-spline carrier hub
> welded to some bar stock and a circular dish, to which the blades are
> attached. My welded carrier hub how has a positive connection to the
> lawnmower blade -- if the blade can't turn, either it will stall my
> tractor, or sheer the 5/16" bolts that hold the blade -- I'll let you
> know how this goes! I'll post some photos later...
>
> While sorting through the solutions to the problem, I considered
> using the whole rotary cutting assembly, just mounted upside
> down. The benefit of the rotary cutter blades, is that they are
> designed to "jump stumps," or get smaller, if they can't cut through
> something. Essentially there are two independent blades, each
> mounted on only one bolt -- as the blade gets "to speed" the
> centrifugal force pushes the blade out. I could see how this design
> parameter could be useful when mixing papercrete, say the mixer
> "hits" a phone book, or large, un-pulped mass-- rather than stalling,
> or breaking the blade, the blade would simply retract and slide
> around the obstacle. Also, the rotary cutter blades are generally
> 3/8" - 1/2" thick, so definitely less likely to break than a
> lawnmower blade. If anyone has experience using a traditional rotary
> cutter blade assembly in a papercrete application, I'd be interested
> in your experience.
>
> Nori, since you're using a rotary cutter gear box, just make sure
> you've got a positive connection to the gear box output shaft splines
> -- tightening down the bolt just doesn't do the trick...
>
> warmest regards,
>
> Eric
------------------------------------
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/papercreters/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/papercreters/join
(Yahoo! ID required)
<*> To change settings via email:
mailto:papercreters-digest@yahoogroups.com
mailto:papercreters-fullfeatured@yahoogroups.com
<*> To unsubscribe from this group, send an email to:
papercreters-unsubscribe@yahoogroups.com
<*> Your use of Yahoo! Groups is subject to:
