Reliability issues with Form 2

Hi all, wanted to start a topic about reliability issues with the Form 2 printers as mine have had numerous issues over a short period of time including 1) not recognizing tanks, 2) massive resin overflow, 3) weak laser issues (twice!), 4) motor jam, 5) cartridge floor sensor went bad, all of these over an 18 month period. Right now, 3 of 5 printers are down with the above issues with a total repair bill of 3x $850 to get them working. Wondering if it is worth the repair cost, I could buy 3 Elegoos for less than the repair cost of one Form 2, and with the factor of much lower cost of operation and repair. I have read a number of posts regarding reliability, is this the real case? Should I just move on to something more reliable noting that I lose the print volume and automatic features (which seem to be at the heart of many Form 2 problems) rather than pour money down a sinking ship? Thanks

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Don’t think elegoo is going to be a panacea. We have Form 2/Form3/Elegoo/Epax.

  1. Elegoo’s build volume is a lot smaller
  2. LCD is a consumable and will die after 400 hours of use
  3. Support is there, but we had enough issues where it wasn’t worth my time to fix, so threw it out. My unit at home is working fine though, no issues.
  4. Elegoo you have to calibrate the plate/height. Depending on how much force you need to get a part off, you may need to do this a lot.
  5. Chitubox is garbage software. They are coming out with a pro version, let’s see if it solves my main complaints.
  6. Open resin also means settings may have to be tweaked. I’ve used some resins that work with stock settings, others do not.

If it was me, I’d buy an Epax X10 and use it in conjunction. Find yourself a resin that works really well out of the box. If you want high temp or high tensile grade resins be prepared to do testing.

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Hi, and thanks for your reply! Yes, the Epax is also on my radar, as one of the machines to check out, on youtube it seems to be the one that most user like, thanks!

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I’ve had an Anycubic Photon for a bout 8 months, and have printed quite a bit on it (at least 3 liters), and I’m pretty sure I’m getting close to 400-500 hours of print time. The LCD shows no signs of wear, and from what I’ve read on other sites, the LCD life expectancy is more like 1000 hours.

Even so, the cost to replace the LCD is only about $80, so in the grand scheme of things it costs about the same as a FormLabs resin tank. Speaking of resin tanks, I’m still on the original one. The FEP has survived just fine.

Considering the low cost of resin, and FEP film, having to replace the LCD every 500-600 hours is more than acceptable.

You these things don’t have the nifty bells and whistles of a Form 2. calibration needs to be done manually, but then again, you only have to do it once in a blue moon. for me, once I got it properly calibrated (first 2 prints), I haven’t had to change it since.

ChituBox is NOT garbage. It’s not as slick and automated as PreForm, sure enough, but it does have features that i wish Preform did.

For example in preform you can only control the size of the support connection point. In ChituBox you can control the size of the actual support branch along it’s entire length.

Another feature is the control over support placement. I don’t mean the point where it connects to the model, rather the location of the support branch in relation to the model. With PreForm, on small models, far too many times you end up with support branches that are so close to the model surface, they end up being fused to it, and you have a lot of cleaning to do.

One other feature, and this is something Preform users have been asking for, for a long time, is the ability to export a supported model back to STL. Yes, ChituBox does that. And because of it, I’ve been using this feature occasionally to export a supported model, then import it into Preform to printed on my Form printer.

I still have my Form 1+ printer and keep it for those occasions when I need to print something bigger that wouldn’t fit on the Photon, but the Photon is my go to printer right now. Yes, it’s a basic printer, but it just works!

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The LCD is very definitely a consumable, we have done a lot of work on the life expectancy of LCD panels in a testing environment to produce empirical data on the life expectancy of LCD screens

Wavelength of the light source and the actual power of the UV energy are the two deciding factors for any screen life (not forgetting that there are a number of different manufacturing techniques for LCD screens. The fact that UV DESTROYS the LCD structure over a period of time is an unavoidable issue if you are going to use UV energy as the light source.

One of the greatest issues is the fact that the UV light source suffers significant power loss through the LCD screen, typically with a full colour display we will measure a loss of as much as 99% of the starting UV energy -once it meets the LCD screen, so if we have 100mw/cm2 of UV energy at 405nm at the light source side of the panel we will often only see 1mw/cm2 of UV energy available at the build surface in the resin tray

The good news is that 405nm is just on the edge of the critical (destructive) wavelength for LCD screens - they will tolerate significantly longer periods of exposure at 405nm than at 395nm.

The same is true of IR radiation (heat transmitted through Infra red light at a wavelength of 750 - 1200nm) thus cooling of the screen is also an important design consideration with regards the lifetime of LCD screens in masked 3d printer applications.

500 hours is a very good lifetime for an LCD screen, but I would strongly suspect that measured figures of UV energy transmitted to the actual build area are significantly less at that stage of its life than say in hour one of its working lifetime.

But at $80 for a replacement its not really a show stopper, it only becomes an issue in a controlled process where you need consistency and control in the print environment to satisfy certification standards (either today’s standards or the standards in the future - such as those being developed by the FDA for additive manufacture of bio medical parts (including dentistry)

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Thanks D, that is a most informative write up you put up here, most appreciated! One of the things about the hobbyist version of the SLA printers is the relative ease of field repair and low cost parts, something that is really not available with the more expensive pro-grade machines. In the application I need for my printers, I think we may find that the lower cost and ease of repair may be a larger factor than the more professional Form 2, especially regarding the cost of repair and the frequency of breakdown we are currently experiencing.

Any LCD alternatives that solve this filtering of light? Exposure time is a huge impediment to speed, any improvements would be huge.

The biggest improvement is the use of a monochrome LCD screen, they allow roughly 5 times more UV energy through.

However the high res versions of the smaller LCD screens are simply not available as monochrome versions (I guess the demand is not there for the screen manufacturers)

The individual pixel size of the larger screens can be a disadvantage for our type of use

For example a 13.3" Monochrome high res screen - mipi-dsi-interface-lcd-display-13

image

As against a 5.5" screen typically used:
image

Very cool! If the Make community had a need to have more of the higher resolution monochrome screens made, perhaps a manufacturer would get on board, I can see how this technology would really enhance current gen of these 3D printers.

Very interesting. I guarantee that’s a similar display to what Nexa3D is using. Their UV exposure time is less than 1 second. The fact that they claim that the LCD is not a consumable with no slated replacements except under warranty seems to further support that. Figure out what their lubricated FEP film is and you’ve got yourself a cheap very fast printer.

With anti-aliasing I’d imagine the smaller ppcm would still fair well?

“Lubricated FEP” umm…

The monchrome screens tend to degrade at a slightly slower rate than the full colour screens - Thats from testing and empirical results.

Monochrome is undoubtedly better for our use

Yes FEP is wettable. I don’t know what they are using here. The patent says lubricated polymer. NewPro also has what they term a “transparent wettable membrane”. Not sure if one is infringing on the patents of another.

Hi Dxxxx,
My company uses a Form3 printer, but I’ve got a Phrozen Sonic Mini LCD SLA printer. Actually, thinking to get another, even though I’ve already seemed to have lost LCD transmission on my current one (I’m planning to purchase a replacement LCD). I’ve been reading a lot of posts about LCD failures and you seem to have a lot of experience in this area. Is transmission loss always the main failure mode? In some posts people report bad pixels, or lines, or just complete LCD failure - not sure if my power loss is the “usual” issue w/ UV exposure… I’ve been able to compensate for the power loss by lengthening the layer time, however, that will probably only work for a bit longer. Even so, I wanted to look into boosting the LED power to the screen from the 30W LED array used now to get even faster print results. I’m thinking to double or quadruple this even. This guy on hackaday ( https://hackaday.com/2020/11/18/more-leds-means-faster-print-times-for-3d-printer-but-theres-a-catch/ ) got his Elegoo up to 120W and claims it’s still printing fine over 150 hours. That would roughly mean 4X more power to the LCD than I have now (Phrozen apparently uses monochrome LCDs), so maybe(?) it will work?

The biggest problems you face is the destruction of the LCD matrix by extra heat from the unit giving increased UV power. Heat is a big issue and any temperatures of the LCD screen above 80c will cause slow long term damage that degrades its performance. That damage will shorten the print life time of an LCD screen (either colour or monochrome.

UV acts in a similar way and causes internal heating of the LCD materials, again resulting in damage.

Dont forget that the power rating of the UV source is not a true measure of how efficiently its working, only the uv output which is measured as mw/cm2 is an indicator of how well its working. UV LEDS are notoriously inefficient and the efficiency is rarely above 5% of the power in in resulting in UV energy out, the remainder is converted into heat (see earlier notes about LCD damage through heat.

A further issue that needs consideration is one of uniformity of UV power across the build area (through the design of the light source optics). We often see variances as much as 400% across a build area with the cheap printers. In printing terms that’s a nightmare and you want at least 90% uniformity across the build area.

A simple answer for an improvement in print speed is one of these:

They give reasonable uniformity and a side effect of the collimator lens arrangement is it helps keep the LCD cooler.

The only problem is that the light source can be more expensive than the cheap printer…

Hi Dxxxx,
Thank you for the insights!
As per your temperature-accelerated degradation of the LCD from UV exposure, I did notice that they did indeed add a fan to the Phrozen Sonic Mini 4K (no fan in the original “2K” version). I’ll have to check their specs, but I wondered if they now claim a longer lifetime. The LED irradiance on the bottom of the LCDs between the two is not significantly different.
Thanks for those LED sources. That latter one I found has 308 UV LEDs and draws 200W (compared to the 30W in the leftmost and 40W in the middle). Even with the low conversion efficiency you mention and the inclusion of a fan, I’m guessing my LCD won’t last long under that 200W power-house. It should have better uniformity than the two on the left, so maybe I can just drive it at a lower current (maybe 100W).