How to make resin jewelry
The one project where the fast one-part resin is usually the better answer — thin layers, no ratio to get wrong, and a finished pendant in an evening.
For anything up to about 3 mm deep — pendants, earrings, bezels, charms — use UV resin. It is one part, there is no ratio to get wrong, and it sets in 60–180 seconds under a lamp, so a tray of twelve is finished in an evening. Anything deeper than that goes back to a two-part casting resin, because light stops reaching the bottom. Seal dried flowers before embedding them, cast the bail rather than drilling it, and wet-sand the edge through the grits.
Jewelry is the one part of this craft where the fast, slightly disreputable resin is usually the right answer. UV resin is one part — no hardener, no ratio, nothing to measure — and it sets under a lamp in about a minute. At pendant sizes that removes the single commonest failure in resin work, which is a mix that was slightly out and stayed tacky for a week before anyone was sure.
It also removes a problem specific to small pieces: mixing accurately at this scale is genuinely difficult. A 10 mm bangle cavity holds 14.0 ml, and at that size a gram either way on the hardener is several per cent of it. UV resin is poured straight from the bottle.
The limit is depth, and it is optical rather than thermal — the resin absorbs the light that cures it, so past about 3 mm the top sets and the middle stays liquid permanently. The UV resin guide covers where that line falls; anything past it is a two-part casting resin and the ordinary method, which the beginner's guide walks through.
What each piece takes
Volumes are derived from the piece's dimensions. UV resin at $11 per 100 ml, which is expensive by volume and irrelevant at these sizes — a whole tray of twelve pendants is $4.36 of resin. Cure times are per layer under a mains lamp; a keychain torch takes several times as long.
The three things that make a piece look bought rather than made
An open bezel filled level looks like a filled bezel. Filled slightly proud, the resin holds a dome on its own surface tension and the piece reads as glass — and UV resin, being thick, holds that dome where a thin casting resin would run off. Fill to the rim, cure, then add a second small dome on top and cure again.
Almost every homemade piece is identifiable by its edge. Wet-sand from 400 through 800, 1500 and 2000, then polish with a plastic polish or a buffing compound. Wet, always: cured resin dust is a genuine inhalation hazard and dry paper clogs immediately. Ten minutes of this is the largest single improvement available.
Fresh flowers rot inside the cast — the moisture has nowhere to go, and over weeks the petals brown and the piece clouds around them. Anything organic has to be properly dried first, and then sealed with a thin coat of resin or a spray fixative, or the resin wicks in and turns it translucent and dark.
What decides how it comes out
A bezel is a metal cup you fill: no demolding, a finished edge already, and the resin only has to sit level. An open mold gives you a free-standing shape but every face is a surface you have to finish, and the piece has to release. Beginners get a better result from bezels sooner, and more original work out of molds eventually.
Up to 1–3 mm a lamp cures it in a minute. Past that, light does not reach the bottom and it never will — a 10 mm bangle is 5 separate UV layers or one pour of deep pour / casting epoxy. At that point the two-part resin is both faster and cheaper.
The one absolute rule at this scale. Anything that blocks light blocks the cure, so a heavy mica powder load or a white pigment in UV resin gives a set skin over liquid. Translucent tints are fine and are what most jewelry wants anyway. The pigment guide covers the loads.
Uncured epoxy is a skin sensitiser and the sensitivity is cumulative. Nothing may happen for a year of bare-handed work and then a reaction develops that does not go away — at which point the craft is over for you. Nitrile gloves every time, including the pours you think are too small to bother with. Vinyl and latex are not adequate; the resin goes through them. That matters more for jewelry than for anything else in this craft, and it cuts both ways: gloves while you work, and full cure before anyone wears it. A piece that is hard but not fully cured is still releasing unreacted material against someone's neck.
Casting the hole in — a short length of a cocktail stick or a purpose-made pin standing in the mold — gives a clean opening and no risk of cracking. Drilling afterwards is easier to place accurately but resin chips and crazes if you rush it: slow speed, light pressure, and back the piece with scrap wood.
An inclusion dropped into a full cavity sinks or floats, never hovers. Pour a shallow layer, cure it, place the inclusion on the cured surface, then pour over it. With UV resin that is a minute per layer, which makes this the technique it is genuinely best at.
Making a piece
A mains nail lamp of 24 W or more emits both wavelengths and cures a layer in 60–180 seconds. A keychain UV torch is much weaker and much narrower, takes several times as long, and is the usual reason a piece comes out soft in the middle.
Press or desiccate for at least a week — a flower that feels dry can still hold enough moisture to brown inside the cast over a month. Then seal with a thin brushed coat of the same resin, or a spray fixative, and let it set before embedding. Unsealed petals go translucent as the resin wicks in.
Two 2 mm layers cure more reliably than one 3 mm layer, and it costs two minutes. It also gives you a chance to place an inclusion halfway and to catch a bubble before it is sealed in.
Once the light is on the piece is finished, bubbles and all — there is no window in which to fix it. A toothpick, or a moment with a lighter held well back, or simply letting it stand for a minute. UV resin is thicker than epoxy and holds bubbles more stubbornly, so warming the bottle in a cup of hot water helps.
A thin sticky film after curing is oxygen inhibition and is completely normal — the top few microns cannot set in contact with air. Wipe it with isopropyl alcohol, or cure the piece under a sheet of acetate and it never forms. It is not a failed batch and it is not the resin.
Do not look into the lamp. These are genuine UV LEDs and staring at one is the same argument as staring at a welding arc. And the same sensitisation rule applies as to every other resin here: nitrile gloves from the first bottle, not from the first reaction.
Size a bigger piece
Pick UV resin and the calculator answers in layers and lamp minutes; pick a two-part system for a ring or a bangle and it splits the mix into resin and hardener at the tiny weights this scale needs.
Open the epoxy calculator →Print the pour-depth card
Maximum pour depth and cure windows by resin type — the number that cracks a casting. Free.
Estimates, not advice. Every figure on this page is computed from published reference values and standard measures, so your own inputs, equipment and conditions will move it. Nothing here is professional advice — talk to a qualified professional before acting on it.