...and now for something different


#33

Back to the original topic.

So for the past couple of days, I’ve been having some troubles and tribulations with this little bugger, but I think those issues have been sorted now.

First of all, I updated the firmware, and as luck would have it, it created problems. After the update, every print failed in one way or another. Not only that, but noticed that the prints were taking a very long time, so I started watching it print, and noticed that every layer was taking about 40 seconds to print.

for those that are not familiar with DLP/MSLA printer, the first few layers (base layers) have longer exposures (30-40 seconds depending on printer and resin), and subsequent layers have a lot shorter exposures of 6-10 seconds.

In this printer’s case, the base layers were set to 40 seconds, and the rest were supposed to be 7 seconds. After the firmware update, all layers were taking 40 seconds. In fact a print that should have lasted about 5 hours, was still printing the next day some 18 hours later.

Anyway, I re-flashed the firmware, and now it’s working OK. But as I ran out the small sample resin, I bought some Apply Lab Works Modelling Grey for MSLA.

This time the issue is completely different. Even though the exposure rates for this resin are very similar to the resin from Monoprice, it creates such heavy suction to the FEP, that the print fails. It’s virtually impossible to lift the build platform and separate the print from the FEP, even by hand.

After browsing the web for some answers I found a Facebook interest group dedicated to the MP MiniSLA, and it turns out this is a relatively common problem with resins that are more viscous than the MonoPrice resins

What happens, is the bottom FEP itself is touching the LCD screen, and it can create a pretty good vacuum underneath. When the build platform tries to go up, the FEP has no give/flexibility as its stuck to the LCD screen. So the trick is to put a few strips of masking tape around the edge of the LCD with the corners open, so to create a thin separation between the FEP and the screen, and also allow the air to escape/breathe by having those open corners.

I’m printing a model right now, and will post some photos once it’s done.


#34

So here are a a few photos of the print I was running. The first one is the print fresh off the print bed, still wet and on it’s supports.

If you look close, you can see a separation line about 1/4 or 1/3 of the way up, when I paused the print to make sure it was actually attached to the print bed. That pause and lift, left a scar on the print.

The photos below show the model after I removed the supports and cleaned it up a little. The quality and detail are very good for 0.05mm print, and I can go down to 0.025, but this isn’t bad at all. If you look close you can still see a few layer marks here and there, which are due to the coupler between the Z motor and and the threaded rod. I’ll probably replace the coupler they have with a flex coupler I have somewhere around here.

Anyway, here is the output of my MP Mini SLA and Apply Lab Works Grey resin, after only about 4 hours of tweaking during my lunch hour.

BTW, The print time for this model can be seen on the first photo. It took 3:46 hours to complete 996 layers (0.05mm layers).

I arranged the same model in PreForm, at the same angle, and sliced it with default supports. The resulting, model was 990 layers and the print time estimate is 3:31 hours on a Form 1+, and 3:52 minutes on a Form 2 using Grey v3 profile on both.

So the SL Mini is just as fast a a Form printer, a little slower than a Form 1+, and a little fast than a Form 2.

BUT, if I were to pack two of these models on the build platform, the Mini would still take 3:46 minutes, but the Form 2 would take 1 hour longer to print.


#35

That’s got a lot of horrible lines though


#36

Yes, there are a few lines through the print. “a lot of horrible lines” ? I don’t know how you define that but let me put it into perspective. First of all, this is 2" tall model, and some of the lines you are seeing under high magnification are not really immediately apparent when looking at the model. I’ve seen injection molding lines that are A LOT worse.

Secondly, as I previously said, this is work in progress, and I’m aware that there are still a few issues, and I think most can be resolved. Since this printer is at work, and I only get to fiddle with it during my lunch hours, I’ve only put maybe 4-5 hours into it, and that includes tests, and generating different support and trying different settings.

Considering the short amount of time I’ve had with it, I think the results are actually pretty darn good. Sure they’re not up to a Form 2 printer yet, but give me time.

My point is that you CAN get good quality prints with a little work and for little money


#37

You are certainly demonstrating your point that it prints.

The masking tape hack/tweak is pretty interesting, but I wonder if that gap is going to blur the exposure edges of your prints in proportion to the distance. Do you have any interest in quantitative tests for dimensional accuracy/repeatability/material perfformance, and that sort of thing, or are you mostly interested in this printer as a artistic model/miniature/figurine printer where the parts will be painted?

As additional points of comparison, members of this forum may also be interested to hear about tank lifetime, resin changes, large prints, and any other maintenance you find yourself doing in the course of running the printer long term.


#38

Looking at the gun there’s a bunch of lines on there, and then multiple lines along the head and lower on the body. Sure, some injection molded stuff is worse, but you’re not making something injection molded. I’m curious if getting a better coupler for the Z-axis will help with that.


#39

When I bought my Form 1+, I never bought it as a tool for technical models that require utmost accuracy, and I had, I would have been disappointed as the models were never 100% accurate. Even today, my current Form 1+ still has some issues printing very accurate models, it always stretch the prints front to back, and my current setup, is pretty weird (I’ll post more details later when I get home).

I print primarily what you described as artistic models, miniatures or articulated figures, mechs, etc. Almost all my models end up being painted, so I developed my own techniques (or trial and error :wink:) to make sure that interlocking parts fit together. If you are interested in seeing some of the type of work I’ve done, you can look here:

As for the other points you brought up, it’s a little early to tell how long the tank will last or maintenance, as I’ve only had the printer for exactly 1 week.

The tank is made of some sort of heavy nylon type plastic, and has a FEP film on it. Knowing how FEP is supposed to be pretty forgiving in terms of UV wear, I would think it should last quite a while, assuming it doesn’t get physically damaged.

Resin changes seem to be simple enough, pour whatever resin is still in the tank out, then pour in the new resin. When I changed from the original Monoprice Clear to the ApplyLabWorks, I just scraped off as much of the clear as I could, cleaned the sides of the tank, and poured in the ALW Grey. Used a credit card to scrape the bottom of the tank, and mix the resin a little, that was that.

Last but no least, size. As I previously said, this has a pretty small volume, 120x68x150, about half that of the Form 1+. But that’s good enough for the type of small prints I will be doing.

Speaking of prints, last night I set up another print and this morning it was done. This particular one is another Warhammer 40K Sisters of silence print, Saint Celestine. The model was split in 4 parts so it pretty much took up the entire print platform.

Here is the model as it came of the print bed (still wet), and later today, I’ll post some shots of the assembled print.


#40

Saint Celestine model update.

Here is a 6 view around the assembled model. There are a few problems with the model, the bottom feathers of her left wing did not print, probably not enough support, and on the ribbons around her sword, there’s supposed to be a single rose, that just came out like blob.

There are still some supports that need to be cleaned up, as they were very close to the surface of the print, and they got fuse to it. That was my mistake as I put the model in the sun to cure it before I removed the supports. I should know better, but I’ve done this kind of clean up before.

FWIW, I also tried printing this on my Form 1+, and the wings had the same problem as here.

On a side note, this model, was not at the same scale as the the other print (about 36-38mm instead of 48mm), so I’m reprinting it at the right scale on the Form 1+. The re-print is at 0.25mm and it’s going to take 13:08 hours to complete. On Monday, I’ll send the same print to the MP MIni also at 0.25mm so I can do a comparison.


#41

25 microns won’t necessarily turn out better


#42

If you say so.


#43

If you can export the sliced and supported model from the slicer you’re using for the (edit: oops not Moai) Monoprice as an stl or obj or other convertible mesh, you could even print the same model in the same resin at the same layer thickness across the two printers (and send the mesh to someone else to print on Form2/3).


#44

This is exactly what I did to print the the model on my Form 1+, I exported the supported model as an STL, and simply printed it without generating any supports.

BTW, the print is finished and it looks great. I just need to remove it from the supports later this evening.

Today I will start the same print but on the MP MIni.

@Ike, I don’t have a Moai, I have a Form 1+, and a Monoprice MP Mini. The model was placed into Slic3r and I generated the supports inside that program, then exported the supported model to STL, which is what I printed on the Form 1+.

Update: The MP Mini never got a chance to finish the print because someone, at work, powered off the work bench on which I had the Mini, so it stopped about 1/2" into the build. There’s no apparent way that I can restart it from where it stopped.


#45

The thinner layers are more susceptible to damage which can cause some irregularity to the layers


#46

@IkeI did another post in which I posted a link to the already supported model you asked for. So if you’re interested in printing it, here is the link:


#47

sb87j6sbs7i21

Need your opinion about it and suggestion how to make it more detailed?


#48

The spires coming off the ring in the middle, those didn’t have supports?


#49

That looks like it’s PLA printed on a FDM printer.

So if you’re asking for suggestion on how to get more detailed, first get a more detailed model, second, print it on a SLA printer.


#50

Yes they did. Here is the actual model with supports imported into PreForm


#51

On a side note, after nearly a month of trying to get a handle on this printer, I had to call it quits. I just couldn’t get any reliable prints from it, so I returned it.

It doesn’t men I’m giving up on the idea of an MSLA, but that wasn’t it. In theory, it should have worked just fine. In practice, it turned out to be more than I wanted to deal with.


#52

On my side, I have been a Form1, 1+ and now Form2 user and obviously, soon a Form3 user. I’m on the artistic side of the 3D printing for my 3D models, for figurine, cosplay stuff and more. I’m looking for fine details and -visual- accuracy for the details. I’m not doing functional parts and using almost only the Grey resin. Then my comments below are limited to these fields.

I have been looking at these low-cost printers since a while and I have been able to work with the Creality LD-001, the Wanhao D7, and the Anycubic Photon. The last one is the best so far and is the only one I kept and still using times to times. I also have the Slash PLUS from Uniz which is targeting the Form2 when you look at specs and price. This Slash has a build volume of 192x122x200mm which is bigger than the Form2. All these printers are MSLA/LCD SLA.
Of course, price is a key factor for these printers as the Photon is less than USD 300 and all of them can work with 3rd party resin and some of them are… cheap. I paid recently EUR 38 for 1L of Anycubic resin.

But now, if you put aside the price and look at performance, print quality, accuracy, etc. then it’s a different world compared to the Form2: For MSLA, you need to overexpose your model when you need to have supports which are reliable. Most of the time, if you don’t overexpose and/or use larger point size, they will just break. So many time I had failed prints because of that. But if you overexpose your resin, then you will have not the quality you are looking for. As an example, for these printers, I’m using 1mm support tip. Sometimes I even need more… Then imagine how bad are my surfaces and how much post work it requires. Also, because of the screen aspect, you see on curved surfaces the aliasing of the screen. We start to see some antialiasing technics, but it’s not perfect yet… The very cheap ones are using 1 LED which results in bad quality of prints when it’s not located in the center.
Then when it comes to the build volume, some of them can print tall models… but the depth axis is so short, preventing large models.

On top of that, look at the whole ecosystem: Preform is lightyear ahead of the other software. Only Mango/(WanhaoDWorkshop) is close. With most software, you can even add/edit supports which are inside your model. And when it comes to cleaning, you need to buy some containers, etc. I don’t even mention having support (through Formlabs, community or resellers)

The real benefit of MSLA is its cost but also its speed. I printed 19cm at 50 microns in less than 10h with the Slash+. Some printers are very popular and have a good community to help, but not all of them, by far…

Globally, my success rate with the Form 2 is 99% (just two prints failed since I have it and one was my own mistake…). With these printers, it’s so much lower. The preparation time is also a lot longer…

Then in a few words, if you want to try SLA and are on a budget, a printer like the Photon is a good choice. But if you want to be a minimum serious, the Form2 is a no brainer and I think the Form3, if it delivers what is announced with surface details (OMG 0.3mm supports tips!) and finishing, is the way to go. Yes, MSLA can print faster, but I prefer a working and good ecosystem, a slower printer which provides me surface quality and more important, is reliable and that I can trust to deliver my prints.

Sorry, it’s a long wall of text :slight_smile: