Why I have (reluctantly) bought a 3D printer:
I always thought I would never own my own 3D printer – I believed that the quality of results from desktop printing were too poor to be of use, and their cost, space and maintenance requirements were too high. 3D printers in themselves don’t interest me much, only the prints do, so I wouldn’t take it up as a hobby. The presence of low cost 3D print marketplaces allowed me to order prints by uploading .stl files at very reasonable prices and lead times, the fuss of owning my own printer never seemed worth it.
However, things have changed over the last couple of years, so I have changed my mind:
- The marketplaces for 3D printing by amateur ‘desktop’ print shops have disappeared, these have been replaced by higher end shops (for example 3dhubs.com has hidden its individual suppliers behind a single pricing system, and increased the required quality of the shops it uses, both of which have lead to increases in prices). This has made it harder to procure 3D printed parts at a very good desktop quality at a low price.
- Desktop SLA printers have come onto the market at much lower price points. These have small build volumes but high levels of accuracy and detail (x=47microns, y=47 microns, z>10microns for the Anycubic Photon S) that are great for my needs to model making and small component making.
I have purchased one of the cheapest SLA printers, the Anycubic Photon S – the prints are very good quality, but it is hard work (and exactly the kind of work I try to avoid)!
The printer that arrived only printed with half the UV screen working, producing the print shown below:
First test model: neatly divided in two due to screen error
Fixing the printer:
The first suggestion from Anycubic’s support was to detach and reattach the cable from the motherboard to the UV screen, this didn’t work. After that, I agreed to attempt a motherboard replacement (took about 10 days to deliver the motherboard) in return for a free 1 litre bottle of resin (worth about £30), this did the trick and the printer now functions properly. In all, these issues and Anycubic’s reaction to them were disappointing. The printer comes with a neat card saying it has passed through quality control, and yet it still had a fundamental issue. I felt that Anycubic relied too much on my goodwill and technical skill to attempt to fix a defective product, expecting me to perform a motherboard replacement (so incurring up to 2 weeks delay and couple of hours work with no guarantee of a fix) without any form of compensation – I had to threaten to return the printer to Amazon before the free resin was offered as compensation. In my view, Anycubic should have immediately offered a replacement or refund upon learning of an issue, alongside offering the motherboard replacement with an incentive.
First few prints:
Installing the slicer, and the importing the .stl files, generated in Rhino3D was easy and quick. The auto-generator for supports in the slicer are obviously inappropriate so I manually added supports, this was easy. The slicing of files takes around 5 minutes, and the process of saving to a USB and plugging this into the printer is easy (and much less potential hassle than having some kind of Wifi type connection).
I have started with printing some caps to go at the base of an icosahedron (these create a termination of a thin thread and a magnet). The general quality of the prints were very good: nearly invisible layer lines and few visible printing artefacts. Issues to resolve: dimensional accuracy of the inside cup, the printer seems to have over-cured on the inside slightly meaning that the magnets don’t quite fit. I had to increase the diameter of the hole at the top of the cup significantly to make sure it didn’t close up, I need to find ways to print smaller holes reliably.
Printed caps x2: note manually added support structure, plug for scale
First three versions of caps printed, note increased size of center hole until large hole in v3 actually gives an opening
v3 cap modelled in Rhino. The internal reverse fillet doesn’t seem to have had an affect, so will omit in future models.
Pausing print to check on progresss (and probably damaging the prints in the process)
First few nodes:
The first node I printed detached from its supports during the print (I think at the exact moment I paused the print to inspect it and it was lifted out of the pool of uncured resin). I increased the level of support for the second print and this wasn’t an issue. Both prints gave a good initial impression of the accuracy of the machine, showing excellent levels of detail.
Unlike the caps, I seemed to hit the dimensions of the holes for the magnets perfectly here, each one was a consistent push fit, which bodes well for the accuracy of the machine. This level of fit was as good as anything I have had professionally printed. The green resin was a little darker than I had expected, but that is just a note, I have clear resin to try after the green is used up (I could try mixing them?). There are small issues on the node with pockmarks being left where the supports were snapped off – I will need to find ways to improve this over time and practice. There are two instances of z-axis wobble seen in the node, one I believe occurred when I paused the model to inspect its progress.
First and second nodes, first print failed by detaching from supports during the print
Version 2 printed nodes prior to magnet insertion, note pockmarks on top surface where supports have been removed, and ring showing z-axis wobble when print paused for inspection
Printed version 2 node, note excellent fit of magnets and layer lines visible by top magnet
Magnets inserted into version 2 node, note layer lines by magnet and compared to finger print for scale
Other issues noted during printing:
- SLA printing is surprisingly wasteful – so far (over about 4 prints) I have used over 10 pairs of Nitrile gloves, a lot of paper towels, about 300ml of isopropanol alcohol and several resin straining sieves. The waste generated is contaminated by sticky uncured resin which is harmful.
- Avoiding contamination of surrounding areas by uncured resin required discipline and patience.
- Processing prints (e.g. decanting resin) during the day can lead to a skin forming on the resin which then needs to be removed, this is messy and annoying, recommend processing prints at night or with curtains shut to reduce the UV light that is present.
- Print processing needs to take place within a few hours of the print completing (i.e. the morning after the print is run), and you need to plan for this.
- Printing bed often slips during removal of prints, need to re-level after every use, this takes about 3 minutes.
- Filtering the resin back into the bottle often leads to spillage, use a funnel.
In all:
Overall, the experience of owning a 3D printer has been much as I expected: messy, hard work, quite unreliable, but also rewarding, with the occasional result that is much better than expected. If to-order 3D print prices had remained low I would have been right not to purchase one, but times and markets change. However, I really look forward to being able to iterate models over time to perfect small details, and learn a little about the art of producing good results reliably.