Category: 3D Printing, DIY, Electronics
Feb 21
Hictop Prusa i3 3D Printer
I recently came across this 3D printer on Amazon while looking for my next kit to build. I’ll confess that I’d never even heard of a 3D printer kit before and assumed that the precision required by such a machine would simply fall outside what a DIYer could achieve in the garage. I was surprised by the mixed reviews not so much that they were mixed but that there were good reviews at all. A bit more research revealed that this is actually an open source designed printer readily available from many different companies both assembled and in kit form. It also became apparent that this is a tinkerer’s bit of kit with many of the parts themselves 3D printed. At £200 vs £1500 for a mainstream commercial printer I realised I would need some realistic expectations – but at just £200, it was worth the gamble.
What really intrigued me was this idea of a 3D printer making its own parts. Youtube is full of people successfully printing to these kits and showing off their modifications. Typical for a popular open source project, there’s a vibrant community of users sharing alternate parts and build experiences. It was those experiences that helped me settle on the Hictop variant of the Prusa i3, specifically the aluminium model for improved stability/strength over the acrylic framed models. What you’re getting with these kits is a box full of parts, some basic tools and if you’re really lucky, a sparse assembly guide.
The Hictop shipped from the UK and arrived within a couple of days. The parts are sandwiched between two layers of cutout foam in a box about the size of a 21in iMac. It contains everything needed to get up and running including some sample PLA filament and a CD with sparse instructions and videos. It took me about 12 hours to assemble. The directions consist of a PDF full of CAD drawings which aren’t the easiest to make out at times. There is very little description of the build process but there are the occasional Chinglish warnings which aid in assembly. I didn’t find the lack of directions to be a show stopper like many reviewers out there but then that’s part of the £200 realistic expectations. Likewise, the instructional videos contain no real instruction but do help illustrate some of the more involved tasks like attaching belts and calibration.
On several occasions during assembly, I thought to myself ‘this thing ain’t ever going to work’. The bolts that attach to the frame don’t exactly instil confidence and the ‘precision rods’ are of questionable precision. Many of the attachment brackets are made from laser cut acrylic although the main frame itself is made from sturdy CNC V-Slot aluminium – my RatRig camera slider is made of these. The X axis ends are 3D printed parts and are very good quality. I didn’t finish assembly until about 11pm on a Saturday night so didn’t get around to trying the thing out until early on Sunday morning. To my complete astonishment, the printer hammered out it’s first test piece. It wasn’t perfect but it wasn’t too shabby either. This, in fact, was my first time to see a 3D printer working in person and I found the process fascinating; mesmerising even.
The next piece I printed was a personalised box for my 7 year old to put his football cards in. 3D printing is a slow process and this box took over 5 hours to print and wasn’t even at a particularly high resolution. But building the 3D model was a painless process thanks to thingiverse.com which has a searchable repository of models and a way to customise some of them right on the site. I’ve got to say, my son felt like a rock star at school with his personalised box and in the back of my mind, this kit pretty much paid for itself then and there.
But back to the print quality not being perfect. The printer has some issues which is no big surprise. I immediately noticed some banding on the walls of prints and this banding seemed to have the same pitch as the threaded rod that drives the print head up and down. Yep, those precision rods have some visible wobble that translates to the print head and this creates some offset that results in a banding pattern. It didn’t take long to find some alternative parts on thingiverse that allows the X carriage to float on the threaded rod instead of being bound to it. Voila! Banding gone, although that modification did require about 7 hours of print time and 3 hours to disassemble, reassemble and re-calibrate everything. Some of the bearings that come with the kit were also very poor quality. I managed to source some new ones for cheap that look identical. I doubt they are any better but at least the replacements work.
Over the past couple of weeks, I’ve also added a sheet of Borosilicate glass (£2) to the heated bed and upgraded the thin bed carriage with some aluminium strips to improve stability (another £2). I’ve also 3D printed replacement rod ends which are a little more sturdy than the laser cut acrylic. I’m getting pretty consistent results now with PLA, ABS and flexible TPU. ABS is the most challenging due to the higher temperature requirements. I found a mix of dissolved ABS in acetone painted on the glass provided the best way to achieve adherence while painters masking tape is all that’s needed for PLA and TPU. I’ve been sourcing the filament on eBay for about £10 per KG. The flexible TPU costs a little more but is my favourite material so far.
The Hictop Prusa i3 is probably the most satisfying thing I’ve ever assembled. It’s a kit that requires some patience and persistence but it’s not out of reach for most who have the determination. Fortunately, all the electronics worked for me out of the box. It was missing a number of bolts which the company promptly shipped after contacting them (I had already worked around it). The power supply lacked a properly earthed UK cable or a way to safely clamp the cable down but again, this was easy to fix. My completed printer produced fair results right off the bat and with a few modifications using freely available designs, it’s now producing consistent, impressive results. It’s not as polished as an expensive commercial offering and lacks an enclosure but the quality is not far off. At £200, it’s a no brainer entrance into the world of 3D printing.