<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">
<div>For making smallish quantities of clay slip I mix up clay in buckets using a paint stirrer attachment for an electric drill -</div><div>pretty quick and does a good job - I've done cubic meters this way now, and only on my second cheap drill</div><div><br></div><div>also good for making cellulose fibre out of shredded paper as a wonderful additive to clay to bind silts and to increase toughness and durbability</div><div> </div><div>cheers</div><br><div> <span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div>Graeme</div><div>Graeme North Architects</div><div>49 Matthew Road</div><div>RD1</div><div>Warkworth</div><div>tel/fax +64 (0)9 4259305</div><div> </div><div><a href="mailto:graeme@ecodesign.co.nz">graeme@ecodesign.co.nz</a></div><div>www.ecodesign.co.nz</div><br class="Apple-interchange-newline"></span> </div><br><div><div>On 21/04/2009, at 2:25 AM, <a href="mailto:ejgeorge@riseup.net">ejgeorge@riseup.net</a> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Hi Laura,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Here were the responses from our NBNE list - Ben Graham seconds the vertical shaft mixer, Dave Lanfear gives several tips and suggestions, and Sarah Highland offers the German weathered clay technique.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">ej</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Ben Graham responded:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">ej,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><span class="Apple-converted-space"> </span>We mostly use "wet" (non-bagged) clay in Vermont.<span class="Apple-converted-space"> </span>Our process is to put</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">it into 5 gallon buckets or large vats with water right off the bat.<span class="Apple-converted-space"> </span>Then</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">add to vertical shaft pan mixer to make it into clay slip.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><span class="Apple-converted-space"> </span>Drying it and pulverizing it also works in a hotter climate.<span class="Apple-converted-space"> </span>You end up</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">with powdered clay which may be easier for some to work with and create</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">consistent mixes.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Ben</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">-----------------------------------------------------------------------</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Dave Lanfear responded:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">ej,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I have experience processing dry lumps of clay from a site and wet lumps. processing dry is a miserable job requiring a soil shredder. The machine is loud and cumbersome, and its still a lot of work feeding it, though it does separate many of the stones. I don't recomend this from experience.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">There are two processes I use for wet lumps. The first is the old fashioned grapemashing method of people using their feet. This isnt practical for most jobs, but it yeilds a beautiful thick slip, and the bonus of well toned legs.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><span class="Apple-converted-space"> </span>The method I have been using is soaking the clay chunks in barrels or bins of water and mixing it with a big mixing drill and a paddle.<span class="Apple-converted-space"> </span>I've found this requires 2 or three rounds of soaking, then mixing. The result is a nice slip which, after pouring through a screen, can be used directly in the mix, obviously replacing some of the water. The rock and stones all settle to the bottom. I make<span class="Apple-converted-space"> </span>a few hundred gallons of this ahead of time for efficiency. A good mixing drill is critical. I have a dewalt, but a hole hawg works really well</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I understand people using bagged clay for efficiency, but the key to that, I believe, is to use clays that you are familiar with and have tested, as two different brands of ball clay can have drastically different characteristics. I've used ball clays that can be mixed as high as 6 to 1 sand to clay, and have to be in order to avoid severe cracking.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I hope someone finds this helpful</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Dave Lanfear</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">--------------------------------------------------------------------------------</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Sarah Highland responded:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">There is another method for processing clay, if one has the right set-up. <span class="Apple-converted-space"> </span>This</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">is to use the traditional German weathering approach, which is very easy.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">In my case, my clay source is right up the road from my house, and I have an</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">arrangement with the owner of the pit whereby I send him $20 every time I take</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">a full pickup load out.<span class="Apple-converted-space"> </span>We go over there when it has been dry weather for a</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">bit and skim off the top inch of dirt over a wide surface area, put it in trash</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">cans, and store them in my barn for jobs.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Last fall two of us collected and stashed six cans in about an hour. <span class="Apple-converted-space"> </span>The resulting</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">weathered clay mixes up very nicely, acting more like sponges than rocks.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">It took maybe ten to fifteen minutes of paddle mixing per half-barrel tub to</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">make slip, and I think it would have taken much less time had we</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">soaked them overnight first.<span class="Apple-converted-space"> </span>Since then I have hired laborers to harvest the</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">clay a second time. <span class="Apple-converted-space"> </span>The key is to have fairly smooth ground. <span class="Apple-converted-space"> </span>The second</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">harvest was much harder than the first because the pit had been roughed up badly</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">with a backhoe in the meantime.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I have plaster recipes for pudding slip rather than dry clay, and it works fine</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">as I've gotten to know my clay.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">The weathering method is the best I've tried, having rejected the Pig-pen method</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">(remember Charlie Brown's friend?) using a chipper, and having found making</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">slip from fresh-dug clay in a mortar mixer or with a drill to be slow and laborious.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Sarah Highland</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Quoting <a href="mailto:cmagwood@kos.net">cmagwood@kos.net</a>:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div> <blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Laura,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Breaking up wet clay is much easier if you have a vertical</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">shaft mixer. We've been able to put very wet, sticky pure</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">clays into this kind of mixer, add the sand and get a good</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">mix. Same process would have killed any horizontal mixer</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I've ever met.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">There is a made in America brand called Imer that make</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">great electric and gas versions of these mixers.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Chris</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">GSBN mailing list</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="mailto:GSBN@greenbuilder.com">GSBN@greenbuilder.com</a></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="http://greenbuilder.com/mailman/listinfo/GSBN">http://greenbuilder.com/mailman/listinfo/GSBN</a></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div> </blockquote><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">GSBN mailing list</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="mailto:GSBN@greenbuilder.com">GSBN@greenbuilder.com</a></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="http://greenbuilder.com/mailman/listinfo/GSBN">http://greenbuilder.com/mailman/listinfo/GSBN</a></div> </blockquote></div><br></body></html>