11-28-2020, 10:03 PM
I wrote a thread awhile back about how to make leveling the build plate that first time easier, because it drove me nuts. I kept running into the same problem, and managed to put my machine out of order for a couple of months thanks to user error never being able to level it right. Today, I got in and managed to fix it and thought I'd share the updated flash of insight with actual numbers.
The instructions about how to level with a piece of paper are kind of garbage, and prone to all sorts of adjustments and error. However, there's an easier way to do this. Loosen the 2 set screws on the build plate to allow it to move freely. Hit the "Home" button to bring the build plate down as low as it'll go, so that the springs are compressed against the LCD screen without the resin tank in place. Square the build plate up so that it's oriented correctly with the LCD screen, and while it is still sitting on the bottom of the tank tighten the set screws on the side. Tighten the screw on the right first, and when that's in as far as it'll go then tighten the front screw.
This is where it gets interesting. The official FEP according to the packaging is .15 mm, and most slices are .02 to .05 mm. So while it's down all the way set the lift height to 0.1 mm and hit the button to go up twice. This will clear the FEP and give you approximately .5 mm for the resin to flow. Back out of that menu and then hit Set Z = 0. That'll ensure that the build plate is as level as the machine can make it, and it takes the guesswork out of "is the paper sliding freely enough".
These instructions work if you're using the official Elegoo Mars FEP. If you are using an aftermarket one that is thicker, use the manufacturer's instructions to sort out exactly how thick it is, add .05 mm to that, and use that to sort out how high you need to raise the build plate before setting Z to 0. Also, you can get a set of feeler gauges from any auto parts store or Harbor Freight here in the USA. Take the .2 mm feeler gauge and slide it around all sides to make sure things slip freely. It's okay if it's a tight fit, because it SHOULD be a tight fit. You just want to ensure that it doesn't bind in spots. If that happens, then you probably didn't tighten the screws enough and it's not level. Loosen everything, hit the home button, and tighten them again more securely once the build plate is tight on the LCD. If you start a dry run with a print and it heads to the bottom and just grinds then your FEP isn't flush with the LCD screen and you need to repeat these instructions except set Z=0 at .3 mm instead.
The instructions about how to level with a piece of paper are kind of garbage, and prone to all sorts of adjustments and error. However, there's an easier way to do this. Loosen the 2 set screws on the build plate to allow it to move freely. Hit the "Home" button to bring the build plate down as low as it'll go, so that the springs are compressed against the LCD screen without the resin tank in place. Square the build plate up so that it's oriented correctly with the LCD screen, and while it is still sitting on the bottom of the tank tighten the set screws on the side. Tighten the screw on the right first, and when that's in as far as it'll go then tighten the front screw.
This is where it gets interesting. The official FEP according to the packaging is .15 mm, and most slices are .02 to .05 mm. So while it's down all the way set the lift height to 0.1 mm and hit the button to go up twice. This will clear the FEP and give you approximately .5 mm for the resin to flow. Back out of that menu and then hit Set Z = 0. That'll ensure that the build plate is as level as the machine can make it, and it takes the guesswork out of "is the paper sliding freely enough".
These instructions work if you're using the official Elegoo Mars FEP. If you are using an aftermarket one that is thicker, use the manufacturer's instructions to sort out exactly how thick it is, add .05 mm to that, and use that to sort out how high you need to raise the build plate before setting Z to 0. Also, you can get a set of feeler gauges from any auto parts store or Harbor Freight here in the USA. Take the .2 mm feeler gauge and slide it around all sides to make sure things slip freely. It's okay if it's a tight fit, because it SHOULD be a tight fit. You just want to ensure that it doesn't bind in spots. If that happens, then you probably didn't tighten the screws enough and it's not level. Loosen everything, hit the home button, and tighten them again more securely once the build plate is tight on the LCD. If you start a dry run with a print and it heads to the bottom and just grinds then your FEP isn't flush with the LCD screen and you need to repeat these instructions except set Z=0 at .3 mm instead.