                   .:                     :,                                          
,:::::::: ::`      :::                   :::                                          
,:::::::: ::`      :::                   :::                                          
.,,:::,,, ::`.:,   ... .. .:,     .:. ..`... ..`   ..   .:,    .. ::  .::,     .:,`   
   ,::    :::::::  ::, :::::::  `:::::::.,:: :::  ::: .::::::  ::::: ::::::  .::::::  
   ,::    :::::::: ::, :::::::: ::::::::.,:: :::  ::: :::,:::, ::::: ::::::, :::::::: 
   ,::    :::  ::: ::, :::  :::`::.  :::.,::  ::,`::`:::   ::: :::  `::,`   :::   ::: 
   ,::    ::.  ::: ::, ::`  :::.::    ::.,::  :::::: ::::::::: ::`   :::::: ::::::::: 
   ,::    ::.  ::: ::, ::`  :::.::    ::.,::  .::::: ::::::::: ::`    ::::::::::::::: 
   ,::    ::.  ::: ::, ::`  ::: ::: `:::.,::   ::::  :::`  ,,, ::`  .::  :::.::.  ,,, 
   ,::    ::.  ::: ::, ::`  ::: ::::::::.,::   ::::   :::::::` ::`   ::::::: :::::::. 
   ,::    ::.  ::: ::, ::`  :::  :::::::`,::    ::.    :::::`  ::`   ::::::   :::::.  
                                ::,  ,::                               ``             
                                ::::::::                                              
                                 ::::::                                               
                                  `,,`


http://www.thingiverse.com/thing:2027135
Rotocaster / Rotomolder  made from common parts by ElectraFlarefire is licensed under the Creative Commons - Attribution - Share Alike license.
http://creativecommons.org/licenses/by-sa/3.0/

# Summary

**THIS IS STILL A WORK IN PROGRESS!**
Main frame components are solid and work well, bearing and bolt mounts too. The feet need to be modified to include more bracing and pulleys/motor are still being fiddled with(NEMA17 works great but it's the most complicated).
instructions are still being worked on and model files may be reorganized or changed.

That being said. The machine works well and has made an number of urethane, silicon and chocolate casts of different types. I'll include some photos later.
Photos now include all the needed detail, so you should be able to build one from that and help me find any missed mistakes!
If you have any problems, I'll try and respond to comments and fix minor problems.

**PLEASE MODIFY THIS DESIGN**
This was made partly as I wanted something that was easy to make, was flexible in size, didn't use gears and was cheap. My build costs are about AU$35 not including motor.
I'd love for someone to redo this, a lot more care could be taken to reduce the amount of filament required, especially on the corners. The current design was made to be simple and solid.
The aluminium size is common in Australia and I suspect other metric places in the world, however a version may be needed using whatever the nearest imperial size is.
An improved version could also reduce the number of bearings to 6 by  replacing the single large aluminium with two smaller ones, one either side of a single bearing. Like a 'H'.

**Hardware BOM**
3m of 10x20x3mm aluminium. (Lager one was made from 10x20mm bar stock. Heavy!)
Cut list small(150x250): 2x 150mm,  2x 200mm, 6x 250mm, 2x 300mm.
Cut list big size(250x250):  (keep forgetting)
10x 608 bearings
6x M8 Bolt 65mm
1x M8 Bolt 75mm
14x M8 Nut
4x  M8 Nylock (Optional, better machine but harder to work on)
6x M8 Washer
Rubber bands (No.34 100x3mm worked for me)
Optional: GT2 2x6mm belt  + neoprene glue. Or GT2 continuous belt large enough and some way to tension it. (You can use rubber bands instead, but the machine has some strange wobbles and effects. OK for a test, but I'd not recommend it.)
Recommended joiner for GT2 belt: https://www.thingiverse.com/thing:1814419

**Tools**
Metal cutting saw. (Hacksaw works)
8mm drill bit
3mm drill bit
Countersink bit or taperd reamer
Basic hand tools, including ruler.

**Print list**
Due to the number of parts involved, they have been organised into 'plates' to suit a 100mm square print bed(Such as the Up! Mini's) so should work on most printers. Most slices can break these up if you want to fit more on larger build plates.
The machine pictured was printed in cheap Red ABS on an modified Prusa i3 clone. 2 shells top/bottom and 2 on sides with typically 20% infill.

2x Corners
1x either Smooth _OR_ GT2 pulley set
1x everything else
1x motor(optional)


**Optional**
I will not offer help for this side of things. DC motor is cheap/easy to drive, but runs a bit fast and has low torque.
*  https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20170210075356&SearchText=Right-angle+Gear+Motor+car
*  NEMA 17 is strong, controllable but takes more effort. I used an broken GRBL board.
Or NEMA 17 stepper + electronics

Test video:
https://www.youtube.com/watch?v=QeE7XG8RrDU
https://www.youtube.com/watch?v=YhfUAERnrJA

# Post-Printing

*Instructions are going to be fairly minimal and include only critical steps.*
Photos should include enough to build it.  More photos should be added over the next few weeks.

*Cut all aluminium to length. I used to a wood drop/miter saw but it works just as well, if slower, using a hacksaw. Exact lengths are not super critical, however each pair of lengths should be the same or you'll get excess wobble. Clean up the ends.
*Put aside the two pieces of the base and two for the sides.
In all other pieces find the center and mark. Put a bearing in one of the 3d printed side(From 'Leftovers' plate), slid onto aluminum until the bearing hole is centered with the mark and drill 8mm holes using bearing as a guide. You could also use 8mm bit just to mark the center, pilot with 3mm bit then drill through with 8mm.
* Deburr each hole. On the holes that will be against bearings, use the countersink bit to shape the hole to allow clearance for the bearing center to turn. This requires quite a deep countersink. See photos.
*Vertical leg pieces are the same, except the bearing end is aligned with the end rather than center of the aluminium tube. See photos.
*Assemble. The 75mm bolt goes through the handle side. Tape works well to hold the frame together. Once it's aligned, use the 3mm bit to into the aluminium through the locking/securing holes. Using screws of the right size, secure together. Long bolts should also work.
*Use washers as spacers to ensure there is no slop when assembling. 2 washers at the top and 2 at the bottom between the bearings  and nut holder were used.
* If you get to this step I should have more photos/instructions showing the rest.

MORE NOTES:
* Any place that a pulley attaches to a bolt, screw on a nylock first and drop the pulley over that. It'll stop it from moving when in use. A normal nut then retains it.
* You may need extra long screws to attach the side/center pulley to the leg piece. I just drilled right through and put a 4mm bolt in place.
* Top belt guides have 2 washers each between the corner and bearing center if you have the guides with pulley insert side inwards. If they are loose, clean out the retaining lip with a knife and a few wraps of tape stop them from twisting and dropping the belt.
* Once pulleys/guides are in place, THEN add counterweight nuts to the other corners. Make sure the machine can spin freely and has little bias.
Wrap a GT2 belt around them and measure for final size. If you do it with teeth up on the guide wheels, turning the belt over later to ride on the teeth gives a little extra tension if needed, but even slightly loose belts work well.