I have just set up my new 3D printer. However, the build plate keeps slipping while printing. I tried to use binder clips to keep the plate in place, but this makes the build plate unlevel, messing up my prints. What are some other ways to prevent the build plate from slipping. I was considering using duct tape, but am not sure whether this would work.
I use kapton tape to fixate the glass plates to the heated beds on two of my printers, one a Prusa i3 clone, the other a CoreXY. The tape is able to withstand higher temperatures, and is very thin, so it doesn't have the drawbacks of limiting the print area or high chance the nozzle hitting the clips.
I'm not sure what "the build plate keeps slipping while printing. I tried to use binder clips to keep the plate in place" means, but if you have a build surface and a bottom heated bed, you can look for "silicone thermal pad 0.5mm".
You can put it between build surface and lower bed, so that it will increase friction and there won't be any slipping, even without clips.
You can also look for "thermal conductive rubber silicone cloth 0.3mm" which is fiberglass reinforced and thinner, but with a maybe worse thermal conductivity. It is however more tear resistant, which helps when you remove the build surface.
If your clips aren't holding down your build plate, make sure your nozzle isn't crashing into the plate and moving it. A build surface between the clip and surface or adhesive might help keep the clip from slipping on the top surface. A rubbery gasket material that can withstand you heated bed temperatures, such as the silicon FarO mentions, can keep the bottom of the plate from slipping. This is the most important surface not to slip.
Apparently, Oscar's option is to tape down the edges of the build plate. I have used Kapton tape to cover torn build surfaces. As Oscar mentioned, it is thin enough for the nozzle to pass over. Kapton tape can be a challenge to adhere at high bed temperatures, such as 110 °C. For that option it's probably worth checking the adhesive specs if they vary for different Kapton tapes.
Those two options aren't mutually exclusive and could be used together. You could even put clips over the Kapton tape at higher bed temperatures if it is an issue.
PEI sheets are the most common build surfaces and already have an adhesive surface. Kapton tape seems to be the surface most resistant to damage, but a sheet that covers the entire build surface is expensive. Kapton seems to do a better job of releasing PETG. Otherwise, I use Elmer's glue sticks to protect the build surface.