Thanks for the help. Great forum
You can use the tank for different materials. You do have to clean it well and be careful with which solvents you use to clean it as you can damage the PDMS layer (you don’t want to do this).
If the tank has already been used extensively don’t count on getting good prints. The tanks have a lifetime (usually 1-2L of resin use depending on which resin you use and the size and layout of your parts).
You can read up on how to replace the PDMS layer yourself inexpensively.
What solvents can be used. I did order a new tank today as the current one is in pretty rough shape. So I won’t be able to do any printing till early next week.
The tanks are consumables, intended to wear out. Going back and forth between two resins, vs. having two tanks probably doesn’t save you any money in the long run. And the wear and tear on the tank you clean will be higher, not to mention the resin you lose when cleaning and the costs of the solvent (you need a water-based cleaner, anything else will probably attack the PDMS or the Acrylic). My recommendation is that if you plan to print multiple materials you buy multiple tanks to do it. Ultimately, I think it’ll cost you less and you’ll have fewer potential problems.
You can use IPA to clean the PDMS OK, but that’s very difficult to do without getting it on the tray itself which is made of acrylic and will break down in IPA. However, it’s not super difficult to do, what I do to keep things from getting messy is to use a plastic syringe to suck out the resin (instead of pouring it out which can drip down the outside). So you just tilt the resin to one corner and then use the scraper to push it as you get it out. You can get most of it out that way with just a little bit in the corners and then use a paper towel to get that stuff up.
You don’t need to worry about very small trace amounts being left in the tank afterward because that tiny amount won’t have a noticeable impact with other resin you put in there, for example if you clean out black and put in white it’s not going to be enough black left to make the white resin darker to where it wouldn’t print properly.