A simple easy to construct repstrap using only
- some basic hand tools
- timber and plywood
- liquid nails and hot melt
Build a 3d printer without any printed parts, except for the extruder. Use the money required for buying printed parts to get a good extruder instead.
The objective is to create a repstrap or a temporary 3d printer that anybody can build at home using cheap and easily available materials, to learn about 3d printer and print their own printed parts required for their next printer.
No vitamins are wasted, except maybe a short length of timing belt. The design can accommodate longer smooth and threaded rods.
This design is taking Prusa i3 as reference. So the vitamins required are:-
- 6x smooth rods
- 1x M5 threaded rod
- 11x LM8UU linear bearings
- 4x stepper motors
- 2x 608 ball bearings
- pulley and belts
- 1x coupling
Wood cutting need not to be very accurate or require great skill. Drilling just have to be accurate enough to be able to mount the steppers. Accuracy is required only in alignment during assembly.
The build volume is small, about 120mm x 120mm x 100mm but good enough to print out parts required for the next printer build. The idea is just to build a temporary printer. So there is a lot of wastage in terms of build volume and rod length in return for rigidity of the printer.
Update 20th Sept. 2014
Using 60 pound Spectra braided fishing line for y-axis. It is working better and easier to build.
Materials - 12.5mm x 24mm timber and 6mm plywood.
Liquid nails and hot melt are used to hold the wooden members together. That is for ease of assembly as well as to absorb any warp and bend of timber. Using screws or nails to hold the frame together will introduce tension and will twist the frame in all directions, making the alignment out.
Apparently there are different types of hot melt. In where I live, they are sold mostly in loose form without any label or description. Therefore I am not able to tell which type is suitable. Choose the type that is hard and rigid in stick form. It appears to me that those look white(slight yellowish) or less translucent is harder than those that look clear or translucent. Be sure to heat up the glue gun until it is really hot and oozing before gluing operation to get a strong bond. I don't know about using hot melt in colder environment, especially hot melt on cold metal, but maybe heating up the metal parts before applying the hot melt might help to get a stronger bond.
Liquid nails is optional. In fact the frame holds up quite well with just hot melt, just like my built. But liquid nails helps in ease of alignment during assembly, and I believe increases the rigidity of the frame also. Anyway it acts as as security to hold the wood together.
(Disclaimer: I will not be responsible for anything that might happen due to building or operation of this design build, be it due to bad gluing or not.)
Print out the dxf file and prepare the materials required. Cut out the print out and paste on the prepared plywood to cut or drill accordingly.
The build requires a flat surface like a glass table top or big floor tile. As I had not taken any pictures during my bulid, please refer to the illustrations and pictures to get an idea of the method of assembly.