Printing from Liquid Resin

[Casey Burns]

Am now at this moment 3D printing a foot joint based on my flute designs. Last winter I decided that the 3D printers with the filament were just not accurate enough to do this. I just received yesterday one of the printers that use a liquid resin bath. They are a bit more of a hassle to use for sure. However, the resolution is astounding at .047mm This is well within the range at which I can slightly ovalize the bore in my designs. The plastics used are about the same density as Mopane. These are the same plastics used for fillings and other dental nightmares. They are tough, not especially brittle, water resistant and archival.

I am in the process of laying out an entire flute, fingerholes and all at least roughed out at this stage. The printer is too short to do the head joint and upper middle joint in one piece but I can simply separate these joints into two pieces. If the prototype passes my testing, I will be getting a larger printer that allows me to make all the parts of the flute as they should be, and in one pass.

This is exciting!

Casey

[PB+J]

What were your conclusions about Richlite?

[WaltP]

Sounds very cool. Please let us know how it works out.

[PB+J]

is this the kind of printing where the object emerges like venus from the bath?

[MadmanWithaWhistle]

I've never considered trying to print a flute out of resin for anything more than prototyping. I have a Formlabs Form 3 I've been using to prototype whistles, but the resin seems quite heavy (and expensive!) to make a whole flute out of (perhaps with thinned walls and chimney'd holes?). What machine are you using, Casey? I would think the uncured resin would set off your allergies - it's pretty nasty stuff, increasing in reactivity as laser strength decreases. Formlabs' laser is strong enough that my resin is pretty safe, but I'm still not making my final production models out of it.

[Casey Burns]

The Richlite is not reliable - I used some for a tooling setup and discovered that it will simply break across its grain or in a random direction. Also, the minimum size is a 4 X 8 sheet 1.5" thick weighing some 300+ pounds. I don't have the machinery to handle this!

For making key masters and other small things I am initially using an Elegoo Mars Pro. I have a larger Peopoly arriving in September.

The 3D resins are not that expensive and are very stable. I am using the water washable one for now and its smell is hardly noticeable and I do not react to it. Note that it cures with UV, not lasers in these machines. These machines basically have an LED screen that flashes a bright black and white image of each "slice" that points upward into the bath of resin, and the metal plate that the object first attaches to. The UV light is at 405 nanometers which is the frequency at which the resin reacts and solidifies. After solidification the metal plate moved upwards .05mm or whatever you set it and the next slice is applied.

I do have the machine well vented to the outside as well. I have a small room off my office normally used as a guest room that I am eventually moving this machine, as well as the Peopoly and my SnapMaker Mill into. With the Pandemic it will be a long tome before we have any guests staying here and we have a better guest room upstairs.

[MadmanWithaWhistle]

Just a minor clarification, the laser in the Formlabs is in the UV spectrum, though I understand other systems use the UV-backlit LCD. Keep us updated what kind of results you get!

[Zeng Fengbo]

Hi, after modeling with software myself and providing feedback on several 3D prints of the flute, it appears that the resin flute with retained printed layer patterns produces better sound than polished ones.