Stereolithographic (SLA) 3D printers are becoming more and more popular as of late, with Formlabs leading the charge with their Form 1+ 3D printer. SLA printers are preferred over FFF/FDA printers by those individuals and companies who require extremely detailed prints, with less noticeable layers, while not requiring objects of a very large size.
SLA printers work by using either a DLP projector or a UV laser in order to cure a liquid resin, one layer at a time. This resin is cured and hardened by the ultra-violet light given off by one of these light sources. However, one thing that a lot of people assume when using SLA printers is that when a print comes off of these machines, the objects are already completely cured. This usually is not the case. While the printers usually have the ability to completely harden an object — at least to human touch — there still remains some additional resin that is not completely cured.
To try and find a solution to this, one man named Christopher Barr decided to take things into his own hands, and create what he calls a UV Post-cure Lightbox. Barr, the owner of a Form 1+ 3D printer, wanted to created something that would not take up any additional room on his workbench, so he created a design that would fit under his 3D printer. Killing two birds with one stone, Barr also created his lightbox with “leveling feet” to make sure that no matter what surface it sits on, it will be completely level. This also solves a problem that Barr has had with his From 1+. Since his lightbox sits beneath his 3D printer, it would be able to also level the printer itself.
Barr’s Lightbox measures 27.5cm wide x 20.5cm tall x 29.5cm deep, and provides access via a front door which includes a safety switch that keeps the UV lights inside the box off while the door is open. For the UV lights, Barr used (2) 5 meter self stick LED strips, which included 300 LEDs each, and cost him only $28. They are powered by an internal 12v power supply, and the box which features many 3D printed parts, includes: the motor mount, door aligner, and motor shaft to platter interface. All of the STL files for these parts can be downloaded here.
The box, which cost Barr less than $120 to build, turned out quite nicely, and works just like he had envisioned it to. It fits snug under Barr’s Form1+ 3D printer and almost looks as if it is part of the machine itself.
You can see more details of what went into the construction of this box via the Formlabs forum. What do you think? Is this a good method to finish curing your printed SLA projects? Would you have done anything different in the design? Discuss in the DIY Post-cure Lightbox forum thread on 3DPB.com.