Transparent finish for hollow parts

I"m trying to get a transparent finish on hollow parts. While using a clear acrylic spray paint works well on the outside, I can’t get the internal surfaces coated. I have had luck buying a quart of clear lacquer and dunking the entire part in it, but the fumes are terrible and it takes a while for the lacquer to dry (and the smell persists for days). Anyone have any suggestions of a clear coat I can get in a large enough container to submerge parts and that I can safely use indoors?

1 Like

Hi gentarg,
I just got my Form2 a few weeks ago but I’m a metal-smith and I love
they are kinda the leading supplier in outdoor sculptures… but I can’t speak to resin since I’m new to this field…check out their sealers…they do big sculpture for installations… They are in NY…so call them…they are so nice…Hope this helps:))-ann

Try “Future floor shine”. It is widely used by scale modelers to create glossy surfaces. Dissolves with IPA. Harmless for use indoors.

I have heard that Glycerin works well, I haven’t tried it though.
Non-toxic and widely available, colourless and odorless

Plus, if you remember the commercials from way back, you get to ride around on a little hovering shield. :slight_smile:

+1 on the Future floor shine. Works great, and has a pretty low odor.

I used to paint 1/28 scale MiniZ RC cars, and would dip the bodies in the stuff 2-3 times (about 3-4 hours apart). The finish was absolutely awesome, the “wet” look, and it actually stands up pretty well to minor scuffs you get when racing these things.

1 Like

Someone else posted this on here somewhere… but the clear resin can be used to make the clear parts clearer.

I’ve used a brush to paint clear resin on clear parts, I then put them under water in a UV light, to cure the brushed on resin, it will not clear without the water. The parts come out a lot clearer, and remain so longer, however you can still see bubbles and “whitened” layers trapped inside the part.

I guess this works because it fills and smoothens all the gaps and cracks between the laser cured lines in the resin.

I’ve been thinking of ways to make use of this, without it going on so thick, and keeping it thin, like diluting or warming up the resin to make it thinner, maybe this would help get it inside hollow parts.

I have not had a working MIni-Z in a few years… but I use to frequent… (User: Draconious)

Me too, although I haven’t been active there in a couple of years, but I used to show off some of my custom paint jobs, like this:

BTW, this one, like all my other custom ones were dipped in Future Shine. You can see how nice and glossy it looks

1 Like

i recently tried XTC 3D on clear with great results. Parts are visibly clearer, almost transparent.

I’m not sure I understand how dunking the whole thing in whatever makes a difference, if its hollow and none of the lacker can get inside… it would just be a faster way of applying it on the outside surface. XTC you cannot dunk on, but if you brush it on it should give you a good result.

I bought some XTC to use on my FDM prints, and while it does a decent job, it’s really toxic. After only 10 minutes I was dizzy and nauseous.

I’m not using that stuff any longer.

As fr as how to get something inside a a hollow object, one presumes, it already has drainage holes, so the liquid would get in there, and then you can drain it out.

The bigger concern is whether or not the object has internal supports. They will be clearly visible in side the object.

What about dunking it in this crystal clear from smooth on

They also have other coatings you might want to check out.

I have found the very simplest way to get a transparent item from Clear resin is to let it drip and drain thoroughly while still on the machine and then pop the model off on to a clean polythene sheet and walk straight out into bright sunlight with it. The remaining resin covering the model cures in seconds and the model is then transparent. :slight_smile:


So far, I’ve tried future floor shine and bona floor polish with so-so results. Parts do become slightly more transparent with 2 or 3 coats, but not nearly clear enough.

The issue with the crystal clear coatings are the same as the polyurethane lacquers. The volatile organics make it unsafe to use without masks and/or a fume hood.

I think the best bet may be to try to skip the IPA rinse all together like Hillzzz said, or coating the part with resin afterwards, but for more complex parts with hollow ‘tunnels’ and cavities, skipping the rinse may not be possible for me.

A somewhat more expensive, but simpler solution I’ve been wanting to try is making a 50/50 mixture of clear resin and IPA and trying to submerge parts in it and then UV cure. I need to order a dedicated bottle of resin to try this first I think. Anyone know if pouring some resin out of the resin cartridges on the Form 2 causes any issues with the chip and tracking, etc?

Interesting! Yes, wondering about the cartridges and chips too…But your could always get some from Photocentric so you don’t have to worry about the cartridge thing…they have it for sale in the US now, just came up yesterday…I may give it a whirl: with the dipping…!/UV-3D-Resins/c/20143005/offset%3D0%26sort%3Dnormal

1 Like

Just refiled my FL grey resin cartridge with Grey UV Photocentric.
hopefully it will be OK.

I bought 6 Kgs that with shipping to Chicago was 291 BP or $376.45US
Buying in this country with the cheapest shipping is $396.29US

So its cheaper by $20 to buy from the UK and ship

More interesting…I will check it out!!!

I’ve already experimented with a technique like that: I thinned some resin with alcohol and dipped some test parts in it. It produced a wavy-glossy finish, and each piece had a big pimple on it somewhere. The treated surface came out very transparent but ugly. It wouldn’t be useful for optics because the surface was so uneven.

I’m guessing the pimples formed like those “ice spikes” on a frozen birdbath: as the resin formed a hardened film on its surface it could have pushed un-hardened resin away toward uncured areas, thereby concentrating it at the last area to cure. I’m thinking of repeating the experiment just to photograph a time-lapse of it so I can see what really happened.

Maybe it would work better with a thinner other than isopropyl alcohol.

oh so do it…the result would be fascinating!

I have never thought about doing this. I wanted to get optically clear & transparent models using clear resin so I tried several coatings. The results were good but not 100% perfect. I might as well try your method and see how it turns out.

Thanks for sharing!