Hey guys! Welcome back to part two of making your resin molds super shiny. As soon as I finished with part one, where I discovered that painting on the Siraya Tech resin onto the mold cavity produced extremely shiny results, I figured that there had to be a better way to do this. I knew I definitely didn’t want to paint all of my individual mold cavities like some resin Bob Ross- ain’t nobody got time for that! As soon as I published that first video, I came outside and looked at one of my newest molds on the printer and it immediately hit me. The mold already has a nice thin layer of uncured resin on it, I wonder if I can use this resin to produce a shiny layer.
A couple of quick thins about my print settings. I’ve noticed that moving to a .04 layer line and about a two second exposure for my sculpt resin, that is heated, produces really great results. The other thing I’ve done is add a light off delay Chitubox. Using Chitubox 1.9 basic (which is their free version) you're going to need to upgrade your your firmware to the latest version if you have an Epax E10 printer like me. Links to all of that here.
Once you get Chitubox installed and you can see my settings here. You can use these on any slicer. I think the one thing that I have noticed with Chitubox 1.9 is the rest after retract setting is much easier to use than what it’s normally called, which is a light off delay which involves a lot of math to figure out. This setting, you just plug it in and I have mine at one second and it made a huge difference in the quality of my print. I wanted to share that with you guys because getting the best quality prints is the key to getting this finish. If you have a print that is overexposed it becomes grainy and not as tight which makes this method more difficult and does not produce great results.
So seeing that nice and shiny coat of uncured resin on my mold cavity made me think that there has to be a way that I can utilize this. What I found out over the course of three or four molds is what you want to do is take your mold off of the build plate, get some paper towels and rub the top part of the mold NOT the cavity. You set top edge and all around it with the paper towel to remove as much uncured resin as possible so that what you’re left with is a thin coat of uncured resin inside the mold cavity but the rest of the mold doesn’t have any uncured resin on it or if it does it’s in very small amounts. What will happen is if you hit this with a UV flashlight it cures a very nice, shiny coat if resub inside your mold cavity. If you have any other uncured resin inside the mold, it is likely to get cured in this process and will cause you problems.
So things you want to keep an eye out for is if you have tail cavities or any very fine detail that you have, you want to get the resin out of those crevices. This can be an extensive process when you have a lot of details so you might just want to go with the painting method instead of this one. This method works fantastically on molds with wide areas that you just want nice and shiny.
So you hit it with that UV flashlight again and I just hold it close and run it around the mold for about five to ten seconds total just to set it. Then, you wash it like you would normally do, I use denatured alcohol for my sculpt then I just swish it around and wipe it off and let it dry. You want to get it completely dry before you cure it. You can cure it as you normally would, I use a curing chamber but you can use whatever you normally use it doesn’t really matter. Cure if for about twenty-five minutes which is recommended for sculpt and you’re done! You have a nice, shiny mold! We can check out what it looks like when they get out, as you can see it’s very shiny and I think it’s even more shiny than the painted on resin because this is a much more uniform coat of uncured resin before you actually cure it.
Now I did run into a few problems using this technique. As I mentioned before, details and holes, specifically paddle tail, can get too much resin in there that hasn’t drained and you can’t wash it before this. So if you hit it with the UV light it’s going to cure in there and cause all kinds of problems. You can try to cover this area by gently trying to flush it out, but it’s still an issue. The second issue I ran into is sometimes there’s just a little bit of stuff in the uncured resin and it could be a little piece that flaked off or a hair or any number of things. You just have to keep a watchful eye out for those and pull them out with some tweezers or another small tool. You can always come back with a brush and smooth it out, you just don’t want to disturb the overall uniform look of this coat of uncured resin.
Take Care – Tight Lines