Version 2 is here!
(see at the end of the description)
This is more or less a copy of the "Mini-shredder/Mini-filetador" from Takashi Utsumi
It is designed for wider blades:
Width: 18mm - Thickness: 0.5mm
The cutting edge length: 100mm
(the whole paralellogram is longer)
Links to the original:
1) Weaving -- Make cool woven objects like those described on Utsumis pages.
2) Directly feed it into a hot end (to be designed) for printing (The melting point of bottle-PET is below 260Â°C edit: I sucessfully printed with 250Â°C)
3) Feed it into into a re-extruder to make 3mm filament for bowden printers.
After some testing with version 1 it is clear that PLA is definitely not suitable - the friction heat cuts right through the plastic after just a few 10m of ribbon. ABS might work but I think an incorporated L-Alu-Profie will be better.
Version 2 is aviable !
This one uses an Alu-L-Profile for feasable wear resistance.
You'll either need an aluminum-L-profile of the following dimensions or change the *.scad parameters.
width = 25mm; height = 15mm; (length = 135mm)
To make the production of the alu part easier a drilling & sawing template part is included.
- print the parts with GRASP and TEMPLATE in it's names.
- (Do not print the part with ALU in its name its for future people with cheap metal printing capabilities.)
- Cut the alu-L-Profile cut to the right lengh.
- Put it into the inside of the template.
- Saw and drill all necessary holes and slits into it. (the slots have 20Â° slant angle.)
- Put a short M5 screw through the top hole of the alu-profile.
- Depending on the length of your blade put a longer M5 screw through one of the sequence of holes.
- Put a long M5 screws through the bottommost holes.
- Place the blade between the short and long screw cutting edge facing the slits.
- Screw it tight with two washers and nuts.
- Onto the long screws stick on the grasp part.
- Fixate it with washers and nuts (acorn nuts if aviable).
v1: (dysfunctional due to quick wear)
Due to Friction heat the PLA walls between the slots wear out very quickly.
- After printing drill out the viewing holes at the top and file off any internal mess.
- Put the blade in with the cutting edge facing to the entry side.
- Put a short M5 screw through the top hole facing inward & shift the blade against it.
- Screw down the top of the blade with a washer.
- Put a second short M5 screw throuh the longhole and the hole in the blade.
- insert a second M5 nut with a fitting small wrench from the bottom
- screw it down with an screwdriver from outside.
- The bottom end of the bottle has to be cut off with a conventional Stanley knife.
- The straighter the initial edge you cut is the better will be the PET ribbon.
- BE CAREFUL WITH KNIVES - I WONT BE RESPONSIBLE FOR ANY INJURIES
- PLASTIC EDGES CAN CUT YOU TOO
- With this tool: Never push always pull on the PET!
- Start with the widest channel. It's the easiest.
- Find the right tilt angle: Too steep and it stalls and tears; Too flat and you loose ribbon width consistency.
- Bottles without any embossed structutres are a lot easier to cut.
- Its use is a bit tricky! Be aware that It takes some practice to use it, don't give up right away.
PS: Be prepared to be called a clutterer when starting to collect PET bottles.