Hello and welcome to my first instructable. Being a member of my local hackerspace, this instructable is aimed at people that have access to a laser cutter and a 3D printer. Now days, this should be relatively easy, as more and more fablabs, makerspaces and hackerspaces are springing up all over the world.
I tried to document as best as I could do all the steps involved, including design, finishing and assembly, but if something is unclear, feel free to leave a comment and I will add the missing info.
Step 1: Requirements
Willingness to learn
Access to a 3D printer (I've used a Prusa MK2S)
Access to a laser cutter (minimum cutting area of 30x20 cm)
PLA filament or any other filament that you have on hand.
Plywood or plexiglass (in case you use a laser cutter)
Step 2: Modelling
I consider myself a medium level designer and probably some
steps that I do are unnecessary or can be done in an easier way. You can follow my workflow and methods but if you feel that there’s a better way, I encourage you to try it.
For small projects I use Cubify Invent, as I am used to the interface, but tools like Fusion 360 (which is free for students or educators) have the same workflow and it should be relatively easy to replicate the project.
I will not go through all steps here, but we will be working with basic geometric design. I have chosen a cube with a 70mm side as the main component and everything is measured to fit in that parameter. The corners are filleted with a radius of 10mm for my viewing pleasure but it’s up to you to make any modification that best meets your needs.
Once we have our cups, we will design the tray. I used the same software so we can have a fully printable model, and with another tool we can extract an .svg file for laser cutting.
The widely used format for exporting printable 3D files is .STL and we will export our file with this extension.
The files are available for free here .
Step 3: 3D Printing
I absolutely love the vast amount of choices and flexibility when it comes to 3D modelling and 3D printing, so I will probably get a bit technical here but bear with me.
Even if you don’t have a 3D printer, you can print the objects at your local fablab / makerspace / hackerspace or using an online service like 3dhubs or shapeways.
Since I use Prusa MK2S 3d printers, I will be using Slic3r Prusa Edition (you can download it here) and I encourage you to take a look at it.
For the provided files I recommend printing at 3 perimeters, 20% fill and 0.2mm layer height.
Probably you have seen that we designed only one cup, but the complete assembly has either 3 or 4 cups of different size. So, you might say: “Hey! You haven’t finished designing the thing!”.
Fear not, as 3D models are vector based, it means we can scale the models, rotate them, cut them and so on. The best part is that we can even save modified files as .STLs without putting them through design software again.
We will be using the Scale along Z axis (Z axis = height). This means that we can put for example 60% and make a smaller cup or 130% and make a taller cup. The only drawback here is that we are modifying the entire height of the model, including the base. If the height is too small, the base will be very thin, if the model is too high, the base will be really thick. We would like a constant base height, but as long as we don’t make extremely high or low, the base thickness will vary by a small percentage.
If you don’t have access to a laser cutter, I have included the tray file in .STL format, so you have a fully printable pen holder. I recommend using 20% infill and 0.2 layer height for the tray. As some plastics are shrinking a little bit when cooling down, it might be a very tight fit, so the Tray file is scaled by 2% to compensate any shrinking or machine inaccuracy.
Export the files as .Gcode and start printing ! (If you don’t have access to a laser cutter, skip to Step 5)
Step 4: Laser Cutting
I used the Slice to SVG function in my Slicer software to
create a file that can be used for laser cutting. You can also do this in Tinkercad. For those of you that don’t know about this, it’s an extremely easy to use free, browser-based 3D modelling tool.
My laser software is not .SVG friendly so I had to reconvert it into .DXF format using Inkscape.
Double check the dimensions – square one is 155x155 mm – long one is 230x80mm.
Having 6mm plywood at hand, I used this material to cut the tray. I also wanted a high enough lip so the cups won’t fall easily. Depending on the laser used, the settings can vary, so I can’t say for sure that specific settings will work with everything. If it’s a smaller laser cutter, 2 or more passes might be necessary.
After cutting we need to glue the rim to the base using wood glue. Any type of fast drying wood glue should work just fine. Before doing that, make sure that you don’t use excess glue, otherwise the glue will dry inside the hole and it might affect the cup position. Secondly, as you can see in the pictures, if your wood is not flat, use a weight while drying to make sure you have a solid piece. Gaps and holes are not a showcase of quality.
Drying time can vary. In my case it’s 20 minutes for this fast-drying glue, but it can take 2, 3 hours for other types. It should be written on the label.
Optionally you can sand down small imperfections if any and you are done.
Step 5: Enjoy
As a maker, I always have a great joy when assembling the final pieces and as I come to the end of this instructable, this joy is present in this case too.
I’ve printed the pen holder in my favorite colors, placed it on my desk and put all my pens and markers in it. I am really happy with how it turned out and if you made it, I hope you enjoy it too.
We can only develop and grow with feedback and I will accept any kind of it. Please share your thoughts about this instructable, so I can make a better one next time !