New Phrozen Printer "Sonic Mighty Revo"

[JeffB]

Think I'm on my 10th print for a simple loco body right now. Everything I keep changing is to get rid of ripples from the FEP tension. A big problem was large body mounting lugs inside the body. I finally took them off and will print those separately to glue in place later. Hey it got rid of the ripples.

I don't have nearly the printing experience you have Chris, but this is something I managed to figure out early on...  Big lumps of resin adjacent to thin walls is a recipe for ripples.

Very interesting exchange of opinions in this thread...

I agree with some of all opinions expressed.  There's some science and basic math that helps, but ultimately success comes down to trial and error.  My success rate, once a part it proofed out, is pretty high.  The issue is getting to that point.  I have some things that required 8, 10, or even 12 iterations before I had the part that I was hoping for.

I do wonder if we've bottomed out on a practical pixel size (22µ)...  One thing I'd like to see, aside from a larger format for DLP printers, would be (if) they could dial down the "pixel" size for DLP.  Even though the current size is just fine, due to low light bleed, I wonder what parts would look like with significantly reduced pixel size for that type of printer.  Logically, "smaller must be better...".

We'll see...  It'll be interesting to see what the next "big leap" in this tech will be, rather than incremental change (revolution vs. evolution).

Jeff

[Lemosteam]

Its funny, the early resin printers worked in reverse.  There was no FEP.  The layers were created by a sweep rod that passed over each layer to leave behind the resin thickness on top of the part.  Then, a mirrored laser would trace the outline of the slice fist, to trap all of the resin in a shallow wall.  Then the beam would crosshatch the pool of resin and the bed would lower one slice thickness for the next cross section to be cured by the laser.  Took FOREVER, but I will tell you that in the week long training, NONE of the 12 daily sets of models (one for each student) on the bed had a single print failure.

It was the Hazmat suit that got to me, lol.

[Chris333]

I'm not having "print" failures. I would call them designing around the printer failures 

[rodsup9000]

Its funny, the early resin printers worked in reverse.

  The first resin printer I saw, was in the fall of 2008. It was home built using a DLP projector and a clear Teflon vat. It operated like the what most of us are using now.
I really wanted to attempt to build one back then, but the resin at $200 a litter and the projector was about a $1000, was cost prohibitive. 
 The build area was about what the Anycubic D2 is.

[robert3985]

I don't have nearly the printing experience you have Chris, but this is something I managed to figure out early on...  Big lumps of resin adjacent to thin walls is a recipe for ripples.

Very interesting exchange of opinions in this thread...

I agree with some of all opinions expressed.  There's some science and basic math that helps, but ultimately success comes down to trial and error.  My success rate, once a part it proofed out, is pretty high.  The issue is getting to that point.  I have some things that required 8, 10, or even 12 iterations before I had the part that I was hoping for.

I do wonder if we've bottomed out on a practical pixel size (22µ)...  One thing I'd like to see, aside from a larger format for DLP printers, would be (if) they could dial down the "pixel" size for DLP.  Even though the current size is just fine, due to low light bleed, I wonder what parts would look like with significantly reduced pixel size for that type of printer.  Logically, "smaller must be better...".

We'll see...  It'll be interesting to see what the next "big leap" in this tech will be, rather than incremental change (revolution vs. evolution).

Jeff

MSLA 3D resin printers are now at 18 microns (Elegoo Mars 4 Ultra 9k, Elegoo Mars 4 9k) with square pixels on the LCD, and have surpassed DLP printers in print "quality"...which is a relative term.

DLP printers don't have pixels, since they don't have an LCD screen, and resolution is measured at where the light focuses on the inside of the Vat's FEP, NFEP...whatever relatively clear, flexible membrane is on the bottom of the vat nowadays, and what is measured is the size of the "voxels"...which is the diameter of the focused UV light in the X-Y axes, even though a voxel also has vertical dimension in the Z-axis.

The two DLP consumer-grade DLP printers from Anycubic and Elegoo create voxels that are approximately "equal" to 22 micron MSLA printers (Phrozen Mini 8k machines) with their square pixels, and which have been the "standard" for over a year...but DLP voxels are more sharply focused/collimated than with MSLA printers, meaning the voxels are more easily seen since their edges and corners are sharper.

Although the two, maybe three DLP machines reigned supreme as far as voxel sharpness is concerned on the consumer market for many months, the Elegoo Mars 4 9k machines have superseded them and produce "better", more usable prints for miniature makers and N-scale model railroaders.

Voxel size in the X-Y dimensions on 22 micron MSLA and DLP machines is in the low 50 micron range.  Voxel size on the 18 micron MSLA Elegoo Mars 4 machines is in the mid-40 micron range.

The "sweet spot" for MSLA printers is 8k machines with 10" screens, producing 28.5 to 30 micron pixels at the LCD...combining "sharpness" that exceeds present-day resin resolution capability, maximizing both visible sharpness as well as blur/AA for smooth prints of complex, curved surfaces....plus a much larger print envelope than DLP printers and MSLA printers having 22 to 18 micron pixels at their smaller LCD's.

Cheerio!
Bob Gilmore

[JeffB]

DLP printers don't have pixels, since they don't have an LCD screen, and resolution is measured at where the light focuses on the inside of the Vat's FEP, NFEP...whatever relatively clear, flexible membrane is on the bottom of the vat nowadays, and what is measured is the size of the "voxels"...which is the diameter of the focused UV light in the X-Y axes, even though a voxel also has vertical dimension in the Z-axis.
Cheerio!
Bob Gilmore

Hence "pixel" being in quotes...  I know that DLP's don't have pixels, but thanks for clarifying it for those that might have misread it.

Jeff

[Chris333]

Not a pixel, but a laser beam is round? 

Meaning instead of looking pixelated, it will look like a kid drawn cloud at certain spots.

[peteski]

Not a pixel, but a laser beam is round?

[robert3985]

That got a good belly-laugh!   

Cheerio!
Bob Gilmore

[JeffB]

That's an old joke for those of us in the laser industry.  Our workplace had T-shirts with something similar printed on it.

Jeff

[basementcalling]

My head hurts after reading this thread.

So much expertise on this board it's scary, but in a good way.

I'm off to the library tomorrow to use a Dremel 3D45 filament printer, stone age 3D printing technology compared to what you all are discussing. It'll be the second time I try to get a useful print. My first attempt, an airbrush holder, did well, except the threads on the lid are off just enough that it doesn't want to screw down into the base easily, and when I applied more force to twist it down, part of the handle broke off the top.

Much as I'd love to have a 3D printer in the house, this technology still seems beyond me for now.

[Peachymike]

I wouldn’t let all the preceding banter scare you off, it really isn’t that hard, but it is a process. There is a lot of collective knowledge and experience here, and the fact that an old truck mechanic like me can figure it out and get some pretty decent results shows that there is nothing that special about it. Pretty sure those of us who have learned the hard way would be happy to help you if you ever decide to take the plunge.

[JeffB]

Much as I'd love to have a 3D printer in the house, this technology still seems beyond me for now.

It's not beyond anyone...  Unless it's cost prohibitive for you (not everyone's hobby budget can support it), or you don't have a safe space away from children or curious pets to set up a 3D printing "station".

Resin printing is messy and you're going to spend a lot of time printing the same thing over and over.  Lots of trial and error, as well as practice.

I finally got smart and started documenting things in a notebook.  Exposure times for different resins, but also exposure times for different parts using the same resin, but I don't want to put you off by getting into the weeds here.

If you've got the money and space, go for it.  Once you get going and start having successes, you'll be very glad you did.

I model a pretty obscure scale/gauge combo (Sn2, which is two foot gauge in S scale, using HOn3 track components and wheelsets).  I don't worry about not being able to acquire detail parts for my chosen modeling focus, because I can pretty much make anything I can solid model now.  Throw in having my own laser cutter and machine tools, I'm almost completely self sufficient (I do purchase motors, gears and wheels though).

Jeff