I’m currently on my first resin tray, around halfway through my first bottle of resin. Number of prints is 22, and I’ve been moving my prints around the build platform. I’m very careful with my tray and printer but am already noticing the clouding and “scratching” in the bottom of the tray from prints. At which point should I expect to replace my tray?
Anyone else having this occur?
I hadn’t noticed too much clouding with my first half bottle of resin, but I haven’t had too many issues with printing over areas that were slightly clouded later, either. I haven’t yet tried printing over highly-clouded areas, though I assume it may affect the strength of the cure in those areas. Pitting had occurred on both the tanks I’ve been using, and I don’t attempt to print over those as they’ll likely just deflect and diffuse the laser, possibly curing resin inside the pit and making the hole larger as the part pulls away from it. The pitting usually occurred when large areas of resin were cured hard onto the silicone. I haven’t had problems with pitting when prints don’t get stuck to the silicone, though.
I think the point at which you should replace your tank is when there are no more usable spots on it, or when prints begin to fail over clouded areas, but I think it’s useful to have at least 1 spare handy in case the one you’re using decides to give up. 
Used two bottles of resin and I have no clouding.
I’ve printed almost 1L of white (around 15 prints), with no clouding. That is until 1 evening when I had a print fail and fall into the resin tray. The laser blasted over that part for 6 hours, ruining my tray completely. I almost couldn’t see through the clouded area it created. Sooo, not too happy…
I’m not very happy with how quickly resin trays are failing. I have a Form1+ and we have one at work also. I think its safe to say that its rare to print a full liter of resin before having to replace the tray.
Some have noted they believe that resin pigments can get trapped in the pores of the PDMS when you leave the resin in the tray. Anyone know if there’s any truth to that hypothesis?
Any other tips for extending tray life?
Some people have commented on using rain-x on the base of the tank but I’m unclear as to how that is supposed to prevent the clouding, as you say it occurs due to resin leaching into the pores of the PDMS. I have left white resin in the tank for about 8 days without printing and the PDMS had a whitish layer to it, I ‘massaged’ it with the supplied spatula tool for about 5 minutes and it all became clear again. Generally I would agree that tank life is low for a £60 item, on average I get anywhere between 5-30 prints per tank depending on print size, density and layer thickness. I have successfully re-used tanks using sylgard silicon, but you have to be very accurate in your levelling (I did 5 tanks but only 3 were useable) - it’s something I will probably do again as the cost of tanks is prohibitive - perhaps if the tanks were designed with a replaceable PDMS ‘sleeve’ or even if formlabs supplied a a kit to resurface tanks - a lot of people are doing it anyway.
At work I’ve printed around 8 liters of resin. I don’t think any trays have lasted more than one liter. Prints will start failing on most between 0.5 and 0.9 liters. At home where the resin has been sitting idle in the trays I have some failing at under 0.5 liters even though I make sure the PDMS is clean and the resin if filtered.
The Form1+ is great when it works but the cost of resin tank replacements as well as the short and unpredictable life of the resin tanks are major issues IMO.
The fact that the mirrors get dirty in a relatively short amount of time is also a serious issue that needs to be dealt with. Adding a small fan with a hepa filter to maintain positive pressure inside the housing while printing and when the tray is removed would go a long way toward alleviating that problem.