Friday, October 31, 2025
First Test With "Jelly" Nail Resin
Got enough stuff up and running. Bodged a 12V laptop power supply into the microscope. New USB for the USB microscopes. I got some of the "OXX Cosmetics Cherry UV Gel, Nail Polish, Jelly Finish." Label states ingredients as "Acrylates Copolymer, Hydroxypropyl Methacrylate, Hydroxycyclohexyl Phenyl Ketone, Silica, CI 15850, CI 19140"
This appears to have some kind of dispersion in it (the silica?), but the particle size is not significant for the resolution of the μRepRap. It is very thick, and wants to stay in large blobs. Attempts to make small dots resulted in 50μm-80μm features as per lower left corner of the structure. The approach of using "dipify" software to make a pre-determined shape was abandoned, and a 500μm square manually created by dragging out the initial contact point, recharging the tip for the next side, dragging that out etc. This was Probe One, which is rather blunt, so perhaps different results may come from finer probes.
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| 500μm Square, "Jelly" nail resin |
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| Side view using lower quality microscope |
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| Closeup using trinocular microscope |
An attempt was made to create some kind of tail to hang on to the finished item. The resin was first cured using the built in μRepRap UV LED for 30s, transferred to a 4W UV LED for 180s, tested, then exposed for 8 minutes.
Adhesion to the glass surface was very good. The bulk of the large blob had enough strength to stay intact in the centre, but cracked when removal was attempted. The underside appeared to be of a similar consistency to the top surface. There was a notable lack of the clear, uncured fluid seen around attempts at curing 3D printer resins.
The strength of the resin was insufficient for the edges to be cleanly lifted from the slide though did have cohesive properties and hints of a stable layer were visible. The relatively thin single layer of the experimental square did not have enough strength to survive attempts to separate it from the slide resulting in the following mess:
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| Square destroyed by attempts to lift it |
The "Jelly" nail resin did cure, and was easy to see. It was not immediately possible to create fine structures, and the results - with single layers anyway - were of low strength. Making this work with a finer probe might be challenging, and require multiple passes. I'll call this as being more suitable than 3D printer resin but not ideal. The "Top Coat" is supposed to be thinner and harder, but with poorer adhesion and harder to see. That'll be next, but that's not the only work on right now.
