Filter setter project timeline

Pan Ring Setters 2
Version 1: Pan ring
– Currently in use in some factories manufacturing round bottom filters.
– Round bottom filters nest deeply allowing for denser stacking.
– Hand pressed into molds.
– Variation, using pieces of cut rejected filters.
– Weight is distributed onto filter rims in 3 point compression.
– Weight of stacked filters is distributed in compression cumulatively onto filter rims below.

DSCF08472
Version 2: Interlocking setter block
Abandoned during prototype process due to complex moldmaking process.
– Weight distributed in compression consecutively onto setters.
– Individual filter weight distributed in 3 point compression on rims.
– Interlocking nodes assist with locating setters.
– Hand pressed into plaster molds.

IMGP0268
Version 3: Ring Setter
Abandoned during firing testing.
– Weight of stacked filters is distributed in compression cumulatively onto filter bottoms below.
– Wheel thrown
– Firing test failed due to stress fractures. Possible cause: shrinkage differential, faulty weight contact distribution.

DSCF6259
Verion 4: Pitet Setter
Currently in prototype phase.
– Original master was jiggered, causing various difficulties.
– Proposed masters to be Lathed (CNC) or 3DP.
– Individual filter weight distributed in 3 point compression on rims.
– Interlocking nodes assist with locating setters.
– Weight distributed in compression consecutively onto setters.
– Potential to be manufactured from filter medium.

Preliminary prototype manufacturing method allows for reasonable minimum daily production, however not all materials necessary to build the mechanism are widely available (8″ plastic pipe).
First test firing results proof of concept passed. Next phase begins field trials and feedback process.
Field trials will select a partner CWF factory to produce and test the setters on a production scale. Comparisons will be made in terms of durability, labor time, fuel reduction, packing density, and applicability to various filter shapes.

Video link: http://youtu.be/NLnjDE5jxSY

Setters update.

Here is an update on the filter setters project.

Our first problem was that of alignment. This is something that we struggle with in designing appropriate technology pressing equipment. Finding a cheap and simple mechanism to keep the two halves of the mold aligned
throughout the pressing cycle.

In the case of the filter setter press, the pressures are not extreme, I wish we could figure out how to calculate the pressure curve in solidworks, anyone? facebook
In this case the difficulty of finding 2 pieces of pipe that fit together closely, caused us to try and make the outer pipe to spec. with concrete. We used a piece of 200mm green sewer pipe (expensive at $80) for the main structure. It was wrapped with 4 layers of 6 mil plastic sheet but not taped to the pipe, so the pipe could slide freely. Then placed the parts into a 12″ sonotube and cast quickrete around it.
We also cut holes into the top to fit a branch of maple for the handle.

http://tinyurl.com/qaey3oo

The inner pipe slid out easily (rotated just as the concrete had hardened green), and then the plastic.
We cut a bottom part of the green pipe now for the female mold.

For the male mold, after trying various other methods, we had it machined from aluminum at Armstrong Machine
shop.

http://tinyurl.com/qx8ydf7

This way it could thread directly onto the end of the 5/8″ threaded rod. The cutter is being made now, 1/2″ flat bar and a piece of pipe welded onto some 3mm steel plate. Can I borrow a MIG in Vernon? facebook
This will be cast into quickrete or plaster (running out of quickrete) inside the top part of the green pipe.

http://tinyurl.com/n9xp6pe

Making the female mold was a bit more complicated. We figured out after many tries to cut a profile out of arborite (countertop material $4 for offcuts at homehardware (coated fiberglass)) and to cut a master on a plaster lathe. We used hydrocal here because the pottery plaster from winrock was dead and I didnt want to drive back to Kelowna to return it. It turns out Hydrocal might be better anyway.

http://tinyurl.com/oknjd3w

Since doing this last time we figured out a better way to cast the female mold. As you can see from the photos the mold is unnecessarily in 3 parts since the level was off on the pouring of the second half (tape blowout, oops). It took quite a bit of time to get it to slide in and out of a whole pipe section easily but tightly.
It was scraped with the edge of a fresh Olfa blade.

http://tinyurl.com/q4cso35

The green pipe was a bit warped so it doesnt spin around in the concrete casting as well as hoped. about
100deg but not all the way around. Should still work.

Here are all the photos together on gplus: http://tinyurl.com/qg2cdlc

Kiln Setting

Here we are in the workshop doing more work on the computer than on the workbench, but its nice to have the specs to share.

There has been some work done on designing a special kiln setting to fit more filters into a kiln-load. The ones in the photos below have been made with the same mix as the filter-body.

They are functional, but we wanted to see if we could make them less massive without loosing too much of their structural strength.

This is the kiln post that is being experimented with now:

Original CWF kiln post

The filter posts in use

And here is a photo of the improved version:

Sketchup screenshot of CWF Kiln Posts

or download the sketchup file:

http://potterswithoutborders.com/wp-content/uploads/2011/03/filtersetterversion2.skp