I have been experimenting making glasses for about 6 months now. Great way to amortize printer: save several hundred $ each pair! I used photo of an old frame as starter, and Rhino’d it from there. Purchased hinges in volume from Eyeglass Hinges,Glasses Hinges,Sunglass Hinges. After a few prototypes, first pair got prescription sunglasses lenses (lens crafters, 1 hour) in May. Yesterday (August 1), I printed a more refined pair, and had progressive transitions lenses so I can use as my regular glasses. I used clear resin. Black looked cheap. Clear looks nice, but I plan to experiment with dyes. I tried makerjuice dye added to resin, but that would not print. May try dying during finishing.
Challenges: embedding cutout for hinges precisely! lining up temples and frames exactly at hinge.
Advantages: get exactly a shape that suits you. try prototypes. get bridge and temple exactly correct length and contour for better fit.
Disadvantages: so far, only one color. regular resin tends to lose shape with normal body temperature. So getting a good ongoing fit is a challenge. I think I sorted that out by making precisely correct length temples that conform well to ear and hold glasses up. With earlier pair, I used croakies, but that’s not a great look!
I’d ask FL for an official opinion, but I don’t think any of the resins with the exception of Dental are rated for use in applications like this where the printed resin will be in direct contact with your skin for extended periods of time. The MSDS says resin is fairly benign. But whatever chemicals are leaching out of a print (and there are, or the print wouldn’t have any discernable odor) may not be particularly safe for long term exposure.
Look nice. When I am attaching hardware or need to make the part semi flexible to prevent chipping or cracking I use a heat gun on it. When cool the parts will return to their original properties. No need to over heat and you can tell when it is soft enough without burning. This might be a little safer to tap threads, attach small rivets etc.
In my case I got spring loaded hinges that require no rivets. I got CAD drawing from manufacturer, so was able to subtract hinge cutout from my design. I also modeled screw holes sized to screw inner dimension (less thread) so they would grip. I’ll try to post some hinge pix later.
Those are way cool. I love the clear just translucent. Have discovered you can easily stain it with alcohol inks and it retains its transparency if you thin them down. I’ve found the clear kinda flexable, do you think it will stand up to use?
I have used the sunglasses since May. The temples have splayed out a bit, and I have to use a croaky to keep them secure during activity (I mainly use for golf, tennis, running, etc.). I printed the temples on the most recent pair (in the photo) 1.5 mm thicker in the hopes that they would remain more rigid. So far, so good, but only a week. I could go to hard resin, but then I would have to find some acceptable way to color them because primer gray is not the color I want my eyeglasses.
I’ve been looking at post cure dying in IPA solution using dyes mentioned on this forum. I will do some experiments for next print.
PS, I did ask FL for their input regarding use close to skin. They said the expected: In short, cured resin should be safe, but has not been tested, therefore they cannot recommend it. I did look in detail at the MSDS, and the main issue with resin skin contact is inflammation. None of the ingredients are carcinogenic. So, I think I will keep using unless/until I get an inflammation or skin reaction. I do plan to get transparent adhesive silicone sheets I can put on the major areas of skin contact. If that works well, I will post.
The plastic once fully cured should be safe but there is probably someone out there that has an allergy.
There might be a coating you could put on them that would make it safer and maybe even protect the plastic from continually curing under uv. Not sure where to look for that though.
For stiffness and resilience I have used piano wire inserted into long, thin parts with much success. I had to experiment with the right size cavity, but worked well. A soldering iron works well for inserting shorter rods, or nut inserts, but not great for long rods.
The eye glass adjuster the comes to our factory uses a shallow pan of sand that rests on a hot plat to soften the frames for minute adjustments. This could help you fit up too.
These shapes would be easy enough to recast in urethane. You’d need a pressure pot and air compressor. Probably want to use clear silicone for the mold, and pigmented urethane for the casting. You could even make the mold hold all three pieces at once, so each pour would be a full set of parts.
Smooth-On has an rtv silicone that doesn’t require degassing. I have used it with cold casting but you need to pour it slowly. Simple tapping of the contianer helps. A cold mold 2 part putty silicone might also work. You can make a bed with one layer, set your part in, brush on some mica powder on the cured half then build the rest of the mold with another layer of silicone. You should have some sort of mold frame. This could be wood or metal, nothing special for the cold mold but as long as you can press it down to make sure you have no gaps and all details are captured. Open box and use a board that can fit inside that you can put pressure on and toss some weights should do the trick.
When I did some cold casting with the RTV, my frame was a cheap steel baking pan. Cost less than a dollar at Wal-Mart.
I was just going to recommend this. 3d printing is perfect for prototyping but it’s not ideal for a finished product. Use that part you made to cast that baby!
Castin Craft Clear would give you a nice transparent frame
Thanks for all of the suggestions. I will indeed try the piano wire. I appreciate that casting will give me a broader range of materials and colors. Since I am not making in volume (only for myself) not sure I want to add a whole additional process (including tools and materials) to my already limited workspace. I may have to go there if I cannot get dying to work to my liking.
Regarding cured resin contact with skin, I bought these https://smile.amazon.com/gp/product/B00XLZTVA6/ref=od_aui_detailpages00?ie=UTF8&psc=1
and applied to temples around the ears and nose contact point. Serves 2 purposes: it absolutely eliminates sliding around!!!, and it minimizes skin/cured resin contact - even though I was not terribly concerned about that.
