The first step to every project nowadays is ordering everything you need in order to plan and design while waiting for delivery. Due to a different location, we had to do some modifications to the list of parts, while we also tried to push the total cost of the project down a bit. This summarizes what we ordered and why. A complete list of parts with the total budget will be available on the List of parts page.
Aluminum extrusions
Aluminum extrusions (profiles) are the main building block of this design and the author managed to obtain them from an american distributor of Misumi. This company was not willing to let us order anything from them since we were not a company but lousy normal people.
Ordering from “renowned” shops like REPRAPWORLD
For the extrusions, we were afraid of high import taxes and long shipping times, so we ordered them (together with filament spools) from a “reputable” shop in “the heart of europe” (uncut and for a premium price). The first time, they managed to send the international package to a random mix of our shipping and billing addresses, keeping the street name from one and street number from the other, name from one and the city from the other, and the city-code from one with the door-code to the other. They also did not include either our email address or phone number, so DHL surprisingly wasn’t able to deliver the package.
After going through their slow and troublesome support ticket system, they said they reshipped the package with a proper label. Whether or not they did we do not know, because when we asked what is going on after a month, they responded that the package got lost in a post office in the Netherlands. The only good thing we can say about them is that after these two months, they returned the money to us. If you can, don’t order from Reprapworld.com, we give it 1⁄5 stars.
Aliexpress to the rescue
In the end, we ended up ordering the extrusions on Aliexpress pre-cut to the required lengths for a grand total of $35. While they are not the original proposed by the author and might have a slightly different cross-section, we are hoping that since the design uses 3D printed inserts, we could modify the design according to the parts we have ordered if the original design doesn’t fit.
The 8 mm steel rods were also ordered from Aliexpress and arrived quickly. They were surprisingly good looking and above all: straight.
3D printed parts
The main idea of the author’s open-source project was to replace an expensive metal framework with a cheap combination of 3D printed parts and standard aluminum extrusions. This choice not only lowers the cost, but also makes the parts more easily available while maintaining a high degree of customizibility.
Due to the experiences that the original author shared online, we can start by immediately printing all the parts from PETG, without doing a prototyping PLA print run first (thanks!). We have some advantages coming into the project, since we have a Prusa i3 MK3 3D printer available to us, which should be able to print all the required parts without melting in the process ;).
By a random chance, we ended up buying three spools of PETG filament in Lithuania from an untested (by us) brand of Devil Design in gray color, trying to get as close as possible to the shade of the aluminum extrusions to keep a unified look of the rover.
Electronics
We had a free Raspberry Pi 3 lying around with all the required extensions, which helped a bit with lowering the budget. Apart from that, we ordered everything from Aliexpress. We will see if any choice comes back to bite us, since taxing of incoming packages is unpredictable (at least in Switzerland) and with Aliexpress being the jungle it is, you never quite know what you will get.
We kept the motors proposed by the original project and ordered 2 packs of 5 LewanSoul LX-16A serial bus servo motors. They arrived in good shape even if one of the two packages didn’t make it through customs unnoticed. They arrived with all the promised accessories including the control boards.
Taxes
When ordering from abroad, one must be ready to pay some import taxes depending on how consistent the customs office of their country is. After receiving almost all parts, we can probably recommend others to not build their rover in Switzerland. We were pretty lucky to only have to pay $35 on fees and import taxes, but this number could easily have been three times higher, making the fees a quarter of the whole budget.
Summary
Aliexpress turned out to be a lot more reliable than more local shops and so far, our budget seems to fit below the $500 mark proposed by the original author. This is likely to change as we try to put together the mess that we ordered, wish us luck.