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Open mode reduces the number of things that could go wrong


I recently switched to open mode, as a last resort. I won’t detail the resin spills, and the problems getting my parts to stick on the platform.

I just thought I would list the benefits (as I see them) for using open mode on the Form 2;

  1. No wiper! Take the wiper out of the tray (for the last time), clean it, and put it away. No more watching the wiper… HOPING it does not get too agressive causing a spill, or contact a failed part in the tray causing an even bigger mess. I assume the wiper makes for better parts, time will tell.

  2. No tray heater. Again, not sure what the benefit was, but my printer is in a dedicated room. I’m not printing in my garage. If heat was critical to good parts, why are my unheated parts coming out perfect?

  3. No cartridge. Yup, you can remove the cartridge from the back, auto-dispensing is no long on the menu. Nice concept though. You put the resin directly into the tray. Amazing how fast you can fill a tray to that top line! No more waiting… hoping that dispensing will actually work (did you pinch the rubber thingie?). No more cartridge errors because it does NOT dispense.

  4. When manually filling the tray … real fast BTW … all you have to do is make sure NOT to fill above that top line on the tray. Do this more than once, and you will have it down. It is far easier that clearing a filament jam (just saying).

  5. When printing, most of the automation is disabled, so the print actually starts pretty much right away. No more waiting for all the sensors to be happy.

  6. Speaking of sensors, no more tray not found issues. No more cocking the tray to the side to get the printer to see it!

  7. Form labs slicer wants to know what kind of resin you are using. You may find that one setting is better than another, but I suspect it only sets the heat and wiper and perhaps the laser strength. In short, you can set this however you like since the printer will be ignoring these settings in open mode. Which is fine by me.

OK, I know I’m naive, but after one full printer replacement (thank you Form Labs) and I STILL could not get parts to stick on the platform, moving to open mode allows me to reduce the number of things that could go wrong. I actually have a printer that works.

One last point about parts sticking to the platform. The common factor for parts not sticking was tough resin. At least for me, the tough resin would not stick no matter what I tried. All ofther Form labs resin and Peopoly work just fine… in open mode.


My feelings excatly. Although I leave the wiper in so that there is some agitation. Just make sure it’s locked in position. I also use it to mix the resin when I add more resin or the tray has been ideal for a while. Beats having to wipe down a putty knife.

I would like the wiper to function and feel that should be an option under Settings. It keeps the resin stirred. I use AWL and a good stir is helpful as I mix 2 parts Beige to 1 part Black to get a Grey V3 resin. Works great and I get fantastic prints at .1mm layers. I’ve printed wagon wheels with spokes at 1/4" diameter.

I’m still using the same tray and the same build plate after 4 liters of resin. No derogation to the tray.

Oh, my printer was replace also as the mother board went out. Works great and I run 4 or more prints a day.


This is funny, because as a Form 1+ user, I don’t have any of these little bells and whistles, and when I brought up the idea of using the printer in Open mode on one of the thread where the OP was complaining about constant failures due to sensors, I was berated for my heathen thinking, and was given a litany of reasons why all those things are needed for a successful print.

But then again, what did I know, I only have a Form 1+ … Yet somehow, my prints are just fine…

Anyway, glad to see that I’m not the only one that thinks this way :+1:


What kind of resin do you print in open mode?


Currently I’m using up my FormLabs Grey V3 resin in Open Mode and not having any issues.

Mainly I use ApplyLabWorks 2 parts Beige to 1 part Black mix. Works great with no issues. Wouldn’t mind being able to turn on the wiper but I can live without it.


I’ve used the Form Labs clear, and the Peopoly blue. The Form Labs tough resin is a no go over here.


I use Castable v2 only. I put this question because my form2 has a problem with the heating element, and i need to do a few urgent jobs, so if i can do that in open mode without issues, it woul be great.


You can look at it this way, if the resin is available for the Form 1+, it should run just fine in Open mode.

The Form 1+ doesn’t have a heater or a wiper, yet castable is available for it, so it obviously works without the need for those things.


The wiper helps keep the resin stirred since the pigment will start to settle out of the resin over time and could cause problems for long prints, it also helps expose the coating on the bottom of the tray to oxygen which helps it last longer and helps it be more effective which would reduce the strain on the print when the tray slides during each layer separation phase.
The heater lowers the resin viscosity, when the resin doesn’t flow as easily then indirect lighting from the laser point can end up curing resin that’s around the print from repeated exposure.


So open mode on the Form 2 kinda turns it into a Form 1?


The heater, the wiper, the resin sensors, the cartridge… all great concepts, but they have to work 100%. If even one of these items fails, you have a non-functional printer. If each item works 95%, but you have five things that all need to work, the failure rate is unacceptable.


More or less.

You still have some of the other features like wireless support (I think), and the dashboard, but you no longer rely on the sensors, so from that perspective, you’re like us Form 1 users.

Agree 100%


It runs far better than the Form 1+. I had one and hardly used it because there were so many issues in keeping the mirrors clean.
My Form 2 runs almost 24/7 with no issues. I run jobs back to back with only the build plate being cleaned and new resin added to the same resin tray. Not something that you can do with the Form 1+.


While I don’t run my F1+ 24/7, I have printed heavily at times, and have had to run print jobs back to back that took in excess of 12-15 hours each.

I too run only one building plate (I have a spare but never used it), and the only thing I do to it after I remove the print is wipe it with a paper towel. And yes I just add resin to the tray as long as I don’t need to run a different color, in which case, I use a different tank.

Like you I use the ALW resin, primarily the beige/white, and I’m now almost 3/4 of the way through my second bottle of beige in the same tray, with almost not traces of wear on the PDMS.

As for keeping the mirrors clean, last time I cleaned them was about 4 months ago, and the only thing they needed is a light wipe with a PEC pad. As long as you clean them once, and you don’t leave the machine open (no tray and open cover), they don’t really need constant cleaning.

So I’m not sure why you think the F1+ is not a capable machine, or somehow inferior to the F2. It’s not.


I think it may be important for you to specify that you are using a Form1+

The Form 2 at least works wonders, We’ve been using it daily and have consumed almost 15 liters of resin over more than 150 prints ranging from 3ml to 420ml with 93% print success (most of the fails being prints where we voluntary tested the machine’s limits), no spills and no errors.

Regarding point 1 I think it is clear why the wiper is useful (based on Formlabs communication), it doesn’t add much to the print time (wipes while the built platform finishes its peeling cycle) and at least on the Form2 it doesn’t generate any spills.

I vehemently disagree with point 2, I have had features that would only resolve because the resin was fluid enough to drip off the part between two layers. I think the heater allows for greater repeatability and reliability.

Point 5 and 6 I also disagree with, but mostly because we never had any of the issues you described though

Point 7, the resin type also influences the way supports are generated. I wouldn’t be as bold as to infer that the only thing that is changed is “laser strength”, there is a lot more to is than just power output (exposure time & tracing for example).

However I completely agree with points 3 and 4. While the cartridge system is great (I don’t want to come twice during the week-end to top-up my vat during a 400ml print), it also awfully slow and overly conservative… I currently am printing in Tough with an almost empty cartridge, the prints are 3-5ml each and every time I have to stand in front of the printer for what seems like an eternity for it to “fill the tank” and then warn be that they may not be enough resin in the 250ml vat to print my 5ml part.


Yeah, I have to agree. I’ve got almost 1900 hours on my F2 and I’ve found these systems to be very reliable.

I work around 3 & 4 by putting in a new cartridge when the F2 starts warning about low levels; after a few prints with the new, I pour the remainder of the old into the new). The only issues I’ve had with dispensing were the bite valve on new cartridges being sealed, which shows as “resin sense failure” (I always break them open now) and a recent problem when an old cartridge of Tough had separated in the container. Neither case was a fault of the printer.

I’m wondering if the F2 had some hardware revisions that have changed it. I have an early model and it performs incredibly well.


I have 100% success rate with Form2. I’m really excited for it to fail. (~40 prints so far)


Seems a bit rushed in the initial complaints. Each item has a use. The heater is to “thin” FL resins, wiper to keep pigment stirred and oxygen to PDMS prolonging life. Never had an issue with any feature since my initial firmware update to address the tank issue, which I only had once. Seems like you either got a junk unit full of problems or just didn’t grasp the full concept and function. I’ve seen time and time again, an operator deviate from the suggested workflow or SOP and things go wrong.

Zero issues with my Form 2 aside from a tank read error once. I have Apply Lab Work resin for open mode, but dread the pause lines that you can’t really escape no matter how quick you fill the tank.


Yup… Very reliable IME and the convenience of the cartridge dispensing is definitely worth it for me. I don’t have the ability to see side by side parts of Form 1+ vs. Form 2 to compare “print quality” improvements of wiper and heater. People with Form 1+ will say “the quality is great” and people with Form 2 will say “the quality is great” but I haven’t seen side by side. Considering the amount of work people have put into modifying their Form 1 to have heaters, I would say the heater is a great feature.

The benefit of open mode being a faster print is true and that could help some times, particularly when you have a low or empty cartridge.


I’m not…