UV-curing Epoxy?

I’m a complete ignorant regarding polymers, so my question is maybe foolish, but…

I understand that the resins used in SLS printers is based on acrylates, but I heard of UV-curing epoxys.

Wouldn’t that make super strong parts ?

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What do you want to do with it? Print with the UV-epoxy? Or just connect parts together?

I have a 6-axis robot, and I want to try something like this, but with UV-curing instead of hardener-based curing.
I need a high-strength resin that I can source in large quantities to make large structural parts.

The advantage I see with UV-curing is that it can harden the fibers as they are unwound from the spool, thus limiting the need for supports ; something similar to what Joris Laarman does.

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That’s wild what Joris does!

Yeah, and the bridge is something else.

Err…some insight on resin chemistry anyone ?

it appears that these do uv-curing resins take a look

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Thanks !
I read that there are in fact multiple types of acrylates :
amino acrylates, epoxy acrylates, polyester acrylates, urethane acrylates

Then what type would the Formlabs resin be ?

To my knowledge, epoxy is the strongest ; could it be used for stereolithography ?

the form 2 laser has a 405 nm violet diode and a maximum output of 250 mW. looking at their website the uv-curable resin must be exposed to wavelengths up to 385nm. you’re able to contact them for a quote, maybe try speaking with them see what they recommend

FormLabs resins are UV crosslinking acrylates

I got a few bottles polyester acrylates. This is pretty cool stuff.
Got it from this company: https://www.solarez.com/

Probably won’t work in your form 2 but it’s great for other applications. The polyester stuff has a little bit of flexibility in it. Similar to the formlabs durable resin and doesn’t break easily.

In the MSDS you can find what is in the formlabs resin:

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Than you for that spot-on link : these guys seem to be UV cured resin specialists.
I’m amazed that it challenges 2 part resins in the watersports and hobby market…
Now I need to find the same kind of fellows in Europe :confused:

I ordered it from the UK, was some time ago, but I think they have a distributor list somewhere. They have a lot of knowledge so can give excellent advise.

I tried Solarez resin WAAAY back with my form1. It over cured like a rock, but wasn’t bad when mixed with formlabs resin (50/50) mix. I couldn’t say if it would be any now, no doubt the formulation has changed since i tried it.

the issue will be compatibility.
Different resin families have different affinities and inhibitions.

Polyester, for example, will stick like crazy to glass… where other resins won’t

So proceed with caution. Formlabs has had to very carefully match its resin formulations to the materials the tank and tank floor are made of as well as the built platform.
Be prepared for the fact that epoxies might stick to the tank— or not stick at all to the platform under the stresses the Form 2 applies during peel.

Carbon has an epoxy resin available for their SLA printer.

It has an ultimate tensile strength of 82 MPa and a Young’s Modulus of 2.8 GPa, so it is pretty strong stuff. No idea how the detail or longevity of the part is.

Interestingly it seems to be a 2-part resin so their dispensing system has some trick up its sleeve. I would love to try the stuff in the Form 2 but I don’t know anyone with a Carbon printer. Their business model might be OK with the large companies in R&D but it’s tough to justify their subscription cost.

A 2 component epoxy resin? Really? I wonder how that works.

Very slow cure epoxy mixed with a photoinitiator? So structures get printed but final curing will be done with heat(some 2 component epoxy systems only cure at 65C+)?

Would be fun stuff! Cause there are epoxies that can easily handle higher temperatures where the acrylic resin fails.

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Yeah, they use the UV acrylates to hold the part together in its green state, and then bake it for a few hours at a high temp to set off the epoxy reaction. The issue is just that higher temps will cause the acrylates to sag, so it’s a difficult tightrope to walk.

Photo polymers use the uv light to break the link that separates the 2 components that then link together causing the cure. Epoxy works differently and I don’t think the 2 components can be separated in the same way and require mixing to get them to cross link.

Err… well, how come there are UV-curing Epoxies then ?

To re-center the topic : I’m looking for a fact-curing UV resin which has high strength while not being too brittle, and which can be found at lower price than Formlabs resins.

The goal is to use my robot to 3D print with a carbon or fiberglass filament in a fashinon similar to 3D pens.