There may be something I've missed somewhere that covers this exact topic, but I've seen a lot of discussion over adhesion to the print bed (temperature, glue, hairspray, etc) but I'm wondering about a specific problem.
The attached FreeCad model is something I'm trying to print in ABS. It was designed to be printed laying on its back.
The problem is that when I print, the corners of the slab toward the edge of the heated bed inevitably "boat up" once I'm up to layer 30 or so. By the time I'm done, I have a significant amount of warping up from the bed.
I've measured heating on the surface of the glass, and it varies quite a bit from the thermistor on the bottom of the heated bed PCB. When I read 115C at the thermistor, I read 95C on the surface *in the center* and 75C on the front edge, even less in the corners. I used an IR thermometer and read from above, pointing down toward the glass.
This big variance in temperature corresponds to the spots where I observe the model pulling up from the bed, and leads me to conclude a couple of things:
1. The design of the heated bed PCB may be lacking. It seems you should be able to lay out the resistance heating elements more densely toward the edges so that you get something closer to even heating based on the current supplied. But I don't know enough about electrical design to say for sure, just my gut feeling.
2. Perhaps I need to take a different approach, such as printing vertically and enabling support material in slic3r?
Any suggestions are welcome!
The attached FreeCad model is something I'm trying to print in ABS. It was designed to be printed laying on its back.
The problem is that when I print, the corners of the slab toward the edge of the heated bed inevitably "boat up" once I'm up to layer 30 or so. By the time I'm done, I have a significant amount of warping up from the bed.
I've measured heating on the surface of the glass, and it varies quite a bit from the thermistor on the bottom of the heated bed PCB. When I read 115C at the thermistor, I read 95C on the surface *in the center* and 75C on the front edge, even less in the corners. I used an IR thermometer and read from above, pointing down toward the glass.
This big variance in temperature corresponds to the spots where I observe the model pulling up from the bed, and leads me to conclude a couple of things:
1. The design of the heated bed PCB may be lacking. It seems you should be able to lay out the resistance heating elements more densely toward the edges so that you get something closer to even heating based on the current supplied. But I don't know enough about electrical design to say for sure, just my gut feeling.
2. Perhaps I need to take a different approach, such as printing vertically and enabling support material in slic3r?
Any suggestions are welcome!
