Printing 25 micron jewelry with Form3

[The_Lab_Partners]

Last month I printed a dozen rings to test the Form3’s new light-touch supports for castable wax resin at 25 microns with Preform 3.5.0 and firmware rc-1.6.7-584 (21 May 2020)

First the Good News:

1. 25 micron printing with castable wax resin creates very clean surface detail. As someone who has been running a Form 2 at 25 microns, it’s nice to see the beta settings for jewelry pushed live.
2. The light-touch point supports are significantly smaller than standard supports, and peel off with less damage to the model.
3. The decreased trussing is also notable. Instead of multiple crisscrossed supports, a series of single, vertical supports makes for easier model release.

The Bad News
As many Form3 users have documented (@larsenstephen, @monk2002uk), the Form3 suffers from several deficiencies, none of which are solved for jewelry casting.

1. Layer Shifting: The Form3’s nasty inability to avoid shifting during print creates very specific problems for jewelry models-- if the goal is to make 25 micron surfaces to reduce the need for clean-up, layer shifting dramatically undercuts that value. None of the rings I printed are acceptable for final casting.
   

   

2. Overcuring: The scalloping effect of extra curing between the support connection points actually undercuts the benefit of using light-touch points. At many locations, the over-cure completely enveloped the smaller support.
   

   

3. Misshapen Openings: Especially noticeable in the vertical plane, the fine detail of circular openings are flattened and often result in thin films of cured resin blocking the opening entirely.
   

   

Unfortunately, the output quality of the Form3 for 25 micron jewelry printing still does not match the output of the Form2.

Comments welcome,

JD Davison
Lab Partners Jewelry

[csauve]

Sorry to hear what’s happening to your prints. The reason I’m replying is you comment about scallops and over curing. I’ve been having the same issue with my from two. I have parts with scallops between supports. I’m going to have to try an experiment now and lesson the cure time on some of my prints. Thanks for the inadvertent help.

[Devin1]

I cant speak to Form3 but for Form2 (pending how old your machine is and how many prints have been made on it already) there may need to be some maintenance done on it. Specifically some internal cleaning of galvo mirrors and a couple of other parts. I’ve had to do this on mine in order to get rid of overcure you are describing. Starting a ticket or a chat with FormLabs will be helpful and they can send you proper PDF’s on how to do this. There is no need to send machine back in but you may have to purchase a couple of cleaning supplies.

[The_Lab_Partners]

Here’s one of the longer threads about these problems on the Form3

Bad prints out of brand New Form 3

Hi, everyone, I wanted to post my first prints off my brand new Form 3 and see if anyone has an idea of how big a deal this may be. I opened up the Form 3, went through setup, and downloaded all Firmware updates, I only had Clear V4 so I tried it out on some new models plus reprinted some old stuff I had (with new supports specifically for the Form 3) to compare to Form 2 quality, and, needless to say… I’m not impressed. I definitely like the new surface finish to the clear, but otherwise I h…

[rkagerer]

What you’re seeing mirrors the early results observed in other resins (and current results in some). I can see how those symptoms would be a major challenge for jewelry. Formlabs has come a long way with Black in particular - I’d be curious if your models come out better in that resin (which might indicate there’ll eventually be light at the end of the tunnel), and I hope Castable Wax on the Form 3 will see the similar improvements from further parameter tuning.

Has anyone at the company shown interest in working with you to investigate the issues (at least in regard to your specific prints)?

[The_Lab_Partners]

@rkagerer - Yes, you are correct: these are the same issues highlighted by many Form3 users @larsenstephen’s work with scale military ship models and grey resin being one of the more carefully researched. And black resin prints (and, perhaps now grey resin) are getting much better with firmware tweaks.
For jewelry, 25 micron printing was not ready on the release of the Form 3, and has been in a Beta branch of both firmware and Preform for a long time-- it was exciting to see that folded into the main software, since that hopefully meant the Form 3 was finally “ready for prime time.” (And less back-and-forth firmware flashing when changing resin types.)
The light-touch points felt like a nice reward for having waited so long for the promised benefits of the new Form 3 technology. Alas, they are only available when Castable Wax resin is selected in Preform.
I have not yet submitted a support ticket, I first wanted to see if this is an issue for other jewelry designers.

[lmlloyd]

I’ve only printed maybe five or six pieces of jewelry, since that’s not my normal thing. They came out a little better than what you’re showing, but did still exhibit some of the problems we’ve been complaining about in other resins. The soft touch supports on mine came out fine, but that could have just been luck in the placement and orientation. It definitely still had the wavy surface, and some overcuring.

[The_Lab_Partners]

After updating to Preform v.3.5.2 and firmware rc-1.6.8-588 the problems of over-curing and layer-shifting remain.
This is a picture of a simple four-stone prong setting where you can see over-curing has resulted in a very messy basket (red), and this creates a layer-shift that distorts the smooth pillars of the claws (orange).

-JD
Lab Partners Jewelry

[lmlloyd]

Does it print any better at 50 micron, or is it like other resins, where only 100 micron works?

[The_Lab_Partners]

Good question.
I haven’t tested Castable Wax resin at 50/100 microns for several months-- not since FormLabs released the Beta Preform/firmware for 25 microns. My use-case requires the highest resolution possible.

-JD Davison
Lab Partners Jewelry

[lmlloyd]

Yeah, I understand that. I wasn’t suggesting you move to a lower resolution for production, just for troubleshooting. I’m just curious if the quality wouldn’t actually be better on 50, even though it is lower resolution. I’ve seen that happen with the grey before they improved it.

[The_Lab_Partners]

I’ll make a 50 micron test-print today-- so as a community we can assess Castable Wax resin in the same testing matrix as other resins. It’s a good suggestion, @lmlloyd

Yesterday’s print, after cleaning the LPU glass window, remains plagued by overcuring and layer shifting.

-JD Davison
Lab Partners Jewelry

[lmlloyd]

Yeah, that looks even worse than the 25 micron. It looks like the misshapen holes aren’t even holes anymore. Are they still keeping beta branch of the jewelry-specific firmware alive, or did they kill that beta when they rolled it into the main Preform?

[orwo]

In the PreForm 3.5.1 version, the print dimensions of the rings are bad, they are thicker and wider by about 0.1 mm from the design of the ring. The early version of PreForm 3.1.2 beta of the program is dimensionally accurate, but the printing time is almost 2 times longer than in the latest version and is incompatible with the information.
In both versions of the program from the support side, the printing surface is uneven with a defect and is smudged. Big problem, especially with texture rings.
I print on beta version 3.1.2, vertical without a raft. Advanced settings: Compression correction with 2 mm, joining the early layers of 0.1 mm and ONLY some necessary supports.
Sorry for my english (used translator).

[The_Lab_Partners]

Thanks for the comments, @orwo,
I stopped using the Beta jewelry version of Preform when it was joined to the standard release version, but when I was using it, I also had the problems you describe. Lack of dimensional accuracy, especially with circular forms, uneven surface details, etc.
When I print using my Form2, I typically print without a raft, sometimes with mini-rafts. Since I’m testing the Form 3 with Castable resin at 25 microns, I’m still letting the Preform software build rafts and supports by default.

-JD
Lab Partners Jewelry

[greymatter]

Hi Lab Partners,
Been following your issues with interest, until this image. Bit off topic, but how do you get to that level of polish if you do not mind sharing.

[The_Lab_Partners]

Hi @greymatter, thanks for watching the saga.
The answer to the polishing issue is, like all things in jewelry, “more sanding.”
-JD
Lab Partners Jewelry