Hello,
On the formlabs store it says:
Tanks are consumables
One tank lasts for about 2 L of our resin. With a separate tank for each individual resin color, switching materials is as easy as sliding in a new tank.
What happens after 2L have gone by? Does the surface becomes too shady to work properly?
If I do not change the resin and that I never take the tank apart from the Form, can I expect it to last longer?
What is the current general knowledge on the subject?
Many thanks
marc
Marc,
The vats are consumable. You will notice that over time the PDMS layer will cloud. This happening is just a fact of printing on PDMS. The only way to prevent it is to not print. (Sorry, I had to…)
Sometimes vats do not last the 2 bottles, sometimes you can get 3 or more. The 2 bottles is just a guideline. It really depends on what you are printing and where.
Not changing the resin type will not have any effect (that I have seen). You can’t take the vat apart. You can replace the PDMS layer but that is not extending the life, it is replacing the component that clouds.
Z-vat Industries makes replacement vats for the Form 1 series and I think they are working or have just released a glass bottom vat. I think this helps a little and is better suited for PDMS layer replacement.
I usually just replace the vat when it is at the end of its life. Plan on needing to purchase replacements and/or replacing the PDMS layer. It is just a fact of owning a Form printer.
In my very limited 3d printing history (maybe 90 prints thus far), I have experienced both extremes. I have seen a few tanks clouding up too fast or PDMS layer separating from the tank after just one liter of resin, however this usually coincides with a failure or two. I also have tanks which have lasted well beyond the 2 liter mark. Just depends on a lot of factors.
It probably also depends on what you are printing. 50 prints of 20ml items or 3 prints of 325ml items would make a big difference. Many of my prints are quite large. One piece I have printed a few of is approx 5" x 5" 6.75" using 330ml of resin.
I would say in general, with no swapping, limited or no failures, you could probably expect it to last longer. That being said Murphy’s law kicks in and it all goes out the window.
Also worth noting that ZVat also buys used trays. I am glad I saved all of my old ones. I have several to sell him! 
Thank you all for the quick responses.
@Kevinduhe, 50 prints of 20ml more problematic than 3 prints of 325ml, correct?
Does anyone has experience with the glass bottom tank ?:
https://www.zvatindustries.com/store/p34/(1x)_Z-Vat_2.html
Well it made sense as I typed it…My reasoning was that it puts more wear on the tank (PDMS layer) but possibly not. I am just babbling out loud here, someone correct me if I am wrong. However it probably has most to do with the number of layers total (i.e. how many times has the platform moved up and down on that tank). Keep in mind moving parts around can also increase the lifetime of your tank. If you are consistently printing the same part smack dab in the middle, move it to the corners.
I have not yet used ZVAT glass tanks. Others here have, I’m sure they will be along soon to comment/review.
Yeah. Every layer that prints adheres to both the previous layer and the PDMS. Then, the cured resin is peeled from the PDMS. It takes away a little PDMS with it, eventually wearing it out. If you take a close look at a worn out PDMS you might even see small “pockmarks” caused when supports print in the same spot repeatedly. I learned about this the hard way with my Form1+. If you’re printing multiple runs of the same model, you will significantly extend the life of your tray if you move/rotate the object before each subsequent print run. If your print fills the entire build platform and you can’t move it, rotate 90º each time.
thanks Randy i’ll definitely keep an eye on this
Does everyone agree that tank life depend on how much supports you print. I find that most of my tank clouding is from supports. Less use of support, i think prolong life of the expensive tank. The clouding make slight spots on prints, which can be removed by sandpaper. Very bad clouding will cause parts to fail.
I have received the Zvat for my form 2 but haven’t used it yet…
There are a few variables that impact clouding rate.
The big one is exposure. The more resin is cured in a given area, the more clouding. This is why you’ll see more clouding for support points because the same area is repeatedly cured. Evenly distributing parts on the platform will extend your tank life.
Certain materials also cloud more quickly than others. DentalSG tends to cloud tanks more quickly than standard resins so tanks used with DentalSG tend to need to be replaced more frequently. You can usually get 2-3 liters of resin out of a tank using standard resin if parts are evenly distributed.
I was informed that growing at .0254 clouds faster than at .050
That makes sense since one of the variables is the number of times your print hits the PDMS. So 25 would cloud faster than 50, and 50 could cloud faster than 100.