Getting A Resin Printer?

[Oliveros 11]

Hello Everyone,

 

After now having a FDM 3D printer for almost a year, we now have reached what we feel is kind of the limit in terms of performance, we're still figuring things out but I feel we've got it in the bag pretty much and it's time to expand the operation a bit. 

 

We were looking at getting a resin printer or SLA as they are called but there's not a whole lot of information in regards to how the final parts are. 

https://www.monoprice.com/product?p_id=30994&gclid=EAIaIQobChMIudHVopP86AIVVMDICh1T5QHrEAYYASABEgKYk_D_BwE

 

Anyone have experience with resin printers and the final parts? Are they as good as FDM in terms of strength and versatility or what's the major differences?

[geert_2 558]

On Youtube you can find videos, if I remember well on channels of "CNC-kitchen", and "Maker's Muse", and others (I don't remember the names). These are indepentdent people (not company related) who have done lots of reviews of different products. These printers are getting a lot cheaper and more reliable now.

 

The biggest drawback is that it is a huge mess: prints come out of sticky liquid, and they need to be rinsed in alcohol or similar solvents. This is messy, and creates chemical waste.

 

Also, tiny supports need to be removed, but this should go easy.

 

I don't know if this applies to all printers, but some prints need to be post-cured, after cleaning the model. The printing process only cures a fraction of the resin, the rest is cured in the post-curing.

 

So you need to calculate-in these extra steps.

 

The materials are light-cured, obviously, and they do get very brittle with time, especially in the sun. Under mechanical load, they tend to deform (at least the models I have), even worse than PLA.

 

The huge advantage is that you can make extremely detailed models. Depending on the printer, steps can be so tiny that you almost can't see them, thus no layer lines. Also nearly transparent prints are possible.

 

So I think for jewelry, model railroads and scenery, tiny figurines, detailed moulds for pouring silicone, and that sort of stuff, they can be really great, and well worth the effort. This is hard to do with an FDM printer.

 

Not so much for functional parts that see some mechanical load.

 

After reviewing the Youtube vids, try getting a little bit of the resin, and experiment curing that in daylight / sunlight / LED-spots. Just to see how it reacts and feels, and how hard, stable and brittle it gets, and how easy it is to machine and paint.

 

Also try to get a demo-model from a manufacturer or distributor. Best is to go to a independant distributor in your environment, who has printers from all different brands and technologies on display. Maybe you can get him to make a print, if you offer to pay for the costs.

 

I am talking about the tiny printers here, with usually build volumes of ca. 15cm^3, which cost 500...2000$. Not about industrial 100.000$ machines.

 

I do not have such a printer, but collegues have.

 

This is my view, but of course other people may have different views.

 

Edited April 22, 2020 by geert_2

[Oliveros 11]

Thank you for that information,

 

What we're looking at is the one in the link, just something to make parts similar in size to the Monoprice Ultimate 2 printer which is what we started with, the main issue we run into is the surface finish.

 

I would like to know more about the post treatment though, I was under the illusion the print would be completed fully in the printer, but perhaps that's not the case.

[geert_2 558]

On 4/22/2020 at 9:07 PM, Oliveros said:

...

I would like to know more about the post treatment though, I was under the illusion the print would be completed fully in the printer, but perhaps that's not the case.

 

I do not know this particular printer, so what I wrote are the general issues with most of these printers, as far as I am aware.

 

Printed models come out dripping wet with sticky resin, and that has to be rinsed off. Then supports need to be removed, if any, depending on the model. Whether it requires post-curing in an UV-station might depend on the printer and resin type, some do, some don't. I don't know for this one.

 

You should ask the manufacturer:

- Which cleaning solvents are required: chemical formula? Are these general products ("open source", sort of), or only from that company?

- What is the exact post-processing method?

- Is an UV- or other post-curing station required? If so, which specs? And from which manufacturers?

- Which personal protection is required for handling the chemicals? (usually at least gloves, sometimes also air extraction due to chemical fumes, sometimes special chemical waste-handling procedures)

 

Compare the data you get from the manufacturer with what you find searching on internet or Youtube, from real users and independant reviewers.

 

Edited April 24, 2020 by geert_2
corrected typos

[Oliveros 11]

Good point, 

 

I know this machine has some sort of UV screen on it, so I figure it should be able to cure the product itself, seems dumb if it can't.

 

Good idea, I'll have to collect some information on these points, it's not as widely spread info as I thought it would be, seems to still be new.

[ahoeben 1,955]

21 hours ago, Oliveros said:

seems dumb if it can't

 

How long were you saying that you are using 3d printers again? And you still don't know that 3d printers are dumb?

 

Joking aside, the UV screen is used to partially harden the resin in specific places (layer by layer). The resin is a gloopy mess, and after the print is done the print itself is hardened just enough that you can handle it and "rinse off" the (again: gloopy) extra resin that is all around it. You can't cure the object without first removing the extra gloop because the gloop will cure with the model. You also cannot fully cure the object while it is being printed, because that would start to cure the gloop around the model too.

 

In theory, you could remove the model from the printer after printing, rinse off the extra gloop and the put the model back into the printer to cure using the "uv screen". However, the freshly printed model would still be sticky, and it could easily stick to the printer while curing. The UV light would also be very unidirectional, so the model would not cure evenly, causing warping.

 

Resin printing really is more involved than fdm printing. Sticky too.

[geert_2 558]

Something I forgot:

 

Also ask the manufacturer (or ask other users) which items are considered replacables that wear out?

 

In the early resin-printers of this type, the plastic transparent plate on which the model was built, wore out very quickly: it got opaque and scratched, after which good prints were no longer possible, since the light has to shine through this plate from the bottom. I don't know the life and status of current printers. So you should question about this, and ask prices of replacement parts. How many prints can you do on the same spot, or how many hours does it last, before it has to be replaced?

 

Also ask what the life-expectancy is of the lamp, and the LCD-panel. Depending on the technology used they also might need replacement after x 1000 hours?

 

Concerning the UV-screen: is that a separate cabinet, or separate lamp? Or is that only to protect you from the imaging LCD-panel?

 

If a separate unit would be required, ask if it is included in the package. Maybe daylight can also be sufficient for post-curing some resins?

 

This sort of things is why it would be good if you could come into contact with a user, or maybe a technical school, or product development department. They are far more likely to tell you the annoyances too. Maybe there is a forum for this printer, or similar models?

 

Resin printers in general (I don't know this particular one), can give excellent results. But you have to be willing to deal with the liquid resin that will go everywhere, cleaning chemicals, waste, and precautions.

 

Edited April 24, 2020 by geert_2