Issues with anycubic M7 pinter

[Marc Dobson]

About 2 months ago I bought an anycubic M7 and I'm having a lot of problems with it. Any open topped model which has previously printed fin on my M5s and my elegoo printers is having foxing on the end closest to build plate. This is caused by the suction cup effect between the model and the film. The normal solution to this is to increase the light off time. I tried this I'm currently at 1 min per layer. The slicer now is saying it I going to take 17 hours to print what normally would take 7 but the printer is then taking 3 it is as if it saying it knows better and is doing it own thing.
Has anyone else had this problem?
Marc

 

[Lawrence Boul]

About 2 months ago I bought an anycubic M7 and I'm having a lot of problems with it. Any open topped model which has previously printed fin on my M5s and my elegoo printers is having foxing on the end closest to build plate. This is caused by the suction cup effect between the model and the film. The normal solution to this is to increase the light off time. I tried this I'm currently at 1 min per layer. The slicer now is saying it I going to take 17 hours to print what normally would take 7 but the printer is then taking 3 it is as if it saying it knows better and is doing it own thing.
Has anyone else had this problem?
Marc

The suction cup effect is due to pressure forces resulting from creation of an enclosed volume. You can sometimes get away with this with thick walls, but it's playing with fire. You really don't want uncontrolled lateral forces of any sort impacting the model as it prints. The light off time doesn't really address the issue at all, but may mitigate the symptoms. The simple answer is don't do it.

It sounds like you are printing the model direct on the plate. Nothing wrong with that, I do it all the time, but you need to vent. For something like an open it is easy enough to raise the model a bit on some knife edge supports These cut/snap off cleanly and the surface is easy to make good. You can vent the supports to suit. More layers, but no increase in layer time, so overall you'll be quicker to print.

 

[Marc Dobson]

Model is printed at a 30 degree angle from the base plate. The exact same model prints on my other 3 resin printers with no issues. They take the same time to print as it quoted on the the slicer. The M7 on the other hand prints in about 1/4 of the time quoted.

 

[Lawrence Boul]

Model is printed at a 30 degree angle from the base plate. The exact same model prints on my other 3 resin printers with no issues. They take the same time to print as it quoted on the the slicer. The M7 on the other hand prints in about 1/4 of the time quoted.

First rule of troubleshooting:
Don't tell me why it should work. If that were germane we wouldn't be having the discussion. You need to move on and discover what is actually happening.
Slicers and printers seem to struggle to accurately predict print times. Frustrating and hard to fathom, but it is what it is. If it gets some right and others not then it suggests something is wrong in your set up for the M7.
Low peel force/weak adherence to the film is generally a benefit. But if you have suction cups, low peel force may well result in blowouts. You don't provide enough information to form a view on what is going on and this isn't a printer troubleshooting forum.
But it sounds like you are trying to bull your way through suction cup effects. If you can and it meets your needs then fine. But if you can't then removing the suction cups seems an obvious, typically straightforward and technically sound approach.