r/AdditiveManufacturing

Hi, I'm working on a project in my internship where I have a channel that is currently not producible with additive manufacturing. It's a channel that has multiple 90-degree angles and a decreasing diameter (it's a rectangular cross-section). I've done CFD with nTop to find the exit pressure. So I now have an inlet pressure (200 bar) and an outlet pressure (50 bar).

Would it be possible to somehow create a generatively designed channel that decreases the pressure by the same amount, based on the starting pressure values?

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I’ve built a custom PolyJet-style machine myself, and I’m currently struggling with bed leveling stability. Right now I’m using a spring-based leveling system similar to what’s commonly used in FDM printers, but I’m seeing fluctuations during operation—likely due to vibration or compliance in the springs.

My question is:

Do commercial PolyJet machines (e.g., from Stratasys) use any kind of compliant (spring-based) bed leveling system at all, or are they fully rigid—like precision-ground stages or fixed kinematic mounts?

HP released the MJF 1200 last week at RAPID, and I am curious what others think of it. A 12L build volume printer that prints in less than 12 hours for <60K seems impressive, but the workflow seems incomplete. They have a printer and a powder recovery station, but no other post processing options. Did anyone else get a chance to get hands on with it at RAPID last week? How do you think it stacks up against Formlabs?

We currently have a slew of prusa's and a markforged onyx one that we've outgrown. Boss wants a larger bed, and higher quality/stronger/faster prints. PA6/12 CF or other engineered filaments capable.

I was thinking SLS could be the ticket over FDM. I'm not sure what is tried and true at this price point.

The initial use case is for low volume and prototype of to be injection molded device covers.

I appreciate your input.

Spent the last month dialing in a workflow for printing AI generated miniatures on my Saturn 3. Figured I'd share what works and what doesn't since I wasted a lot of resin figuring this out.

Generate the model in Meshy. I use image to 3D mostly because I can control the pose better by uploading concept art. Text prompts give me random poses that usually don't work for tabletop.

First thing in Blender is check for non-manifold edges. There's always some. Select all, mesh cleanup, make manifold. Then check wall thickness, anything under 1mm gets thickened or it'll break during printing or post cure.

Weapons are the worst offender. Swords, staffs, spears all come out way too thin. I usually just delete them and kitbash replacements from free STL weapon packs. Faster than trying to fix them.

Scale to 32mm in Chitubox, add supports manually. Auto supports miss overhangs on AI models constantly because the geometry is irregular. Manual supports take longer but save failed prints.

Print settings: 2.5s exposure, 0.03mm layer height for detail. Standard grey Elegoo resin.

Success rate after dialing this in is about 80%. The 20% failures are usually models with too many thin floating bits that I missed during cleanup.

Total time per mini from generation to printed: about 45 min of active work plus print time. Not counting the learning curve which was painful.

Worth it for custom campaign minis. Not worth it if you just want generic fantasy stuff, there's better STL packs for that.