Build plate issues

[goofin]

My initial print of the Rook took 5 attempts. Resin printing is brand new to me so I figured it was newbie mistake. Rook finally printed and was perfect. Several attempts printing 1/24 scale model truck rims and still having issues. printer forms first lay or layers then will not stick to build plate. Machine was purchased directly from Elegoo. chitubox software installed without any issues.

Anycubic water wash resin was used for both Rook and wheels. before I start sanding build plate, is there any other ideas or suggestions to try.

[Dan-Gtr]

I know your post is a few days old, hopefully this might help if you haven't already found the solution to your problem. I went though a similar thing with my printers right after I got them. Here's what I'd try if I were you:

1) Make sure your "Zero" point is correct - follow the setup instructions in the manual to reset them and you'll be fine.

2) Make sure your build plate is level before you print - Even though the instructions make this sound like a calibration for a new printer I've found that this is something I need to do frequently. If you've bounced the edge of the plate off a table top or were a little rough getting another print off of it you can knock it out of position. Loosen both of the build plate screws and lower it to the "home" position - use at least one piece of A4 paper between it and the LCD. Tighten the Front Screw First, then the side (per Elegoo). Make sure those build plate screws are tight so they won't slip during printing. I turn the Allen Key around so I can use the long end to get the screw really snug.

3) I have been de-greasing and cleaning the build plate surface before it goes into the printer, this really helped reduce adhesion problems. Most auto parts and large retailers will sell something called "Simple Green" or "Purple Power" in a spray bottle. I spray the bottom of the plate, let it sit for 30 seconds or so and then wipe it dry/clean with a fresh piece of paper towel. You can rinse it with a little water before you dry it but I haven't found that necessary.

4) Look at the FEP film on your resin tank - if it's overly cloudy or scratched that often leads to a print failure. If you've had quite a few failed prints it's highly possible the film has become scratched removing the leftover stuff stuck to the FEP film. In any case, unless the film is pretty transparent it will need replacing to get a successful print. If the film has any deep dents or places where it looks like resin has cured on the bottom, the film will also need to be replaced. Also look at the LCD display, it needs to be "squeeky-clean" to perform at it's best. I clean my LCD before every print using a microfiber cloth normally used to buff the paint on cars. If you have any globs of resin that have leaked onto the display through the FEP film use the "yellow plastic" scraper that came with the Tool Kit to gently remove it. Don't use Metal Tools on the Screen Ever!!! You'll scratch the display horribly.

5) Make sure that you have your exposure times set for the resin you're using. I found it's well worth the time to look up the settings for your printer and resin on the Chitubox website and use their suggested settings as a start point. If you're using a dark resin (like black) it's not uncommon to have to increase the Exposure times to get them to print correctly. There's a calibration tool available for free on the printables.com website called "the cones of calibration" this little piece takes about 30-45 minutes to print depending on your layer height and it will tell you if your settings are correct. I've run this on every resin and every printer (we have a print farm and own a combination of Mars3, Mars3-Pro and Saturn S printers in multiples). I've found there are some variations in exposure times between the machines of the same model. With one printer you should be able to dial your exposures in to perfection. One thing they don't tell you on their instructions is how to read the bottom of the test figure to see if you're "overexposing" the bottom layers. If there's a pronounced ridge around the bottom of the piece or you have to pry like crazy to get it off the build plate your bottom exposure time is too long. Bottom Exposure times should normally be about 10-15 times your normal layer exposure. For example: an Exposure time of 2.5 seconds should have a Bottom Exposure time of 25 to 30 seconds.

7) I don't fill the resin tank to the "Max" line. I fill it to the point where the inside of the tank bends outward and creates a very light line - about 2/3 full. Some resin makers suggest you avoid using a full vat of resin. Make sure you have enough upon starting your print to cover the build plate when it goes all the way down. I've successfully run prints where I had less than 3/4" of resin left in the tank (I hate changing colors where you have to drain and clean the tank).

6) I remove the resin from every tank once I have stopped printing for the day - use the paper filters that came with the printer or resin. I you didn't get any, these are the same filters used for filtering automotive paint so it will spray perfectly. They have a paper body with a mesh section at the bottom. Auto parts stores all have these or you can order them online. Use a big plastic funnel (a little larger than the filter) to support the paper filter. This is gonna stop a lot of spills - put the paper filter inside the plastic funnel and the funnel in the top of the resin bottle. I've made a rig to hold the bottle so it doesn't tip over during the process of pouring the resin from the tank to the filter (I'm kind of clumsy so spills are inevitable). Many people suggest that you not return the tank's resin to the container it came out of, but then, what the Heck do you do with it?!? I use the container it came out of and combine it with the unused resin in the container. I started doing this before I was told you weren't supposed to. I'm sure someone will come up with a thousand reasons why it's bad to do this but up to this point we haven't had any problems doing this - I'm pretty sure it's because we're filtering the resin that was in the resin tank.

I hope this helps.
Dan