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# With Gusto!
Today I'm designing a clay extruder. I've taken [one pass at this](https://gitlab.cba.mit.edu/jakeread/claystack) before, so I know a bit more about what I'd like to see in the end result:
clay should be easy to load,
straight-up plunging the clay is mechanically arduous, but worth it
I want to strong arm this whole situation. The mud will fear my plunger. From the supply chain I'm going to pull a few critical components:
closed loop gt2 for first reduction
bicycle headset bearings to mount
a ballscrew nut, driving
a ballscrew
nema 17 motor & 20 or 16T pinion pulley
I'll use 2.5" ID polycarb tubes to load clay in to, with 12" (off-the-shelf length) sections, assuming 8" used height, that's about 3.5lbs of clay, which is plenty much.
## 1kg Carry or Tube Delivery
My first temptation is to just carry this whole thing around the machine. The laying-down is speed-limited by the process, not by the machine's accelerations... so carrying 1kg on the end of the machine is OK. It's also straightforward, and has a kind of elegance that's hard to find with tubes.
I *am* a bit weary of doing this to the plastic parts of my [gantries](https://gitlab.cba.mit.edu/jakeread/rctgantries/). To that note, I'll also spec parts to design / build a 'bowden' type nozzle delivery... Since size will be a bonus there, I'll pick some ... 1/2" id hose and compression fittings. My notes from before:
```We found that with ~ 20% water added, we could push it through a 1/4" inside diameter tube having ~ 1m of length with only 30psi.```
So, straight up clay (no water), anticipating a similar (hopefully shorter) hose length ... 1/2" ID seems OK, considering the force (that I haven't actually calculated yet) that we should be able to plunge with.
## Design Log
Here's the stick at June 7 2019
Ok, through some of this ...
- nozzle detail ... o-ring, and screw-to-secure, or secure somehow ?
- finish motor mount to pulley side
- consider similar structure & method (alu tabs with 3dp heatset inserts to secure) for bottom lock-in ...
- plate
- fin
- luer lock
- vol / step ? haha
- ballscrew: flip flange side,
- instead of an o-ring seal, use dam-type flange wall?
- or o-ring gets a nest, for slightly oversized o-rings ?
## The McMaster Order
- 8585K31 1/8" Wall 2.5" ID Polycarb Tubes
- 9558K75 O-Rings
- bowden-type hose fittings ... barbs?
- 50915K324 Compression Fitting 3/8" and 3/8"
- 50915K195 Compression Sleeves
- 50915K169 Compression Elbows (for turnaround possibility)
- 4568K135 Turnaround Pipe