Printing a part to the edge of the build plate

[gdub]

Hi, I'm working on a model that will be an actual working prototype to be made from ABS.
The size will be 7" x 10" x 1.5". The inventer would rather not split the part for fear of sacrificing
the integrety of it's strength. Since the bed of the M2 is 8" x 10" x 8", would it be a problem printing
the model to the edge of the build plate?

[jimc]

i have never printed anything myself that runs the exact dimensions but if you can get it to print on the plate and not go over the edge then your good to go.

[gdub]

Thanks for the reply. My main concern is will print head reach to the edge.
Since the part is beveled, the first print layers wouldn't go exactly to the edge, but as
the part grew, would reach a total of 10 inches.

[benavery]

The glass is exactly 10" long, but I just checked my printer, and against the y-endstop my hotend is about 2mm onto the build plate. So you might have to tweak the endstop a bit to get the hotend right back to the edge.

[jsc]

You may be able to get it to work, but I would be hesitant. As for dimensions, I would model a square hollow box that represents your desired maximum dimensions and try to get that to print for a few layers before trying it on a real model, to make sure you can get it to fit on the bed. The other issue is that you will have to really fine tune your bed leveling and z height. There is a slight crown to my bed, so that the center is ever so slightly closer to the nozzle than the edges. You will need to adjust it so that you get proper adhesion on the edges without crashing the head in the center. Use an extra large first layer height in your slicer. Remember to turn off any skirt or brim, since there will be no room for them.

Finally, if a single print part turns out not to be feasible, you should try acetone, or maybe IPS Weld-On #4, as a solvent cement. You are welding the parts together using plastic from both parts to be joined, not gluing them. The joint should be as strong as the rest of the part. In fact, generally stronger unless you are using 100% infill, since you will be attaching wall to wall. Try to model in some registration keys, as aligning large flat surfaces is tricky. Another advantage to splitting your model is that you are liable to have massive warping/adhesion/splitting issues on a full bed print in ABS, and those issues are much reduced by having smaller prints. You could also consider whether a PET filament might be suitable.

[benavery]

Also, if its feasible to print the 10x1.5 edge on the bed (rather than the 10x7), then you can rotate it should easily fit. This is highly dependent on what the model is though, and what direction it makes sense to print in.

[gdub]

Very good points! I really appreciate the replies. I'm thinkin' split the part and welding them now.

[mathisyourfriend]

Also, if its feasible to print the 10x1.5 edge on the bed (rather than the 10x7), then you can rotate it should easily fit. This is highly dependent on what the model is though, and what direction it makes sense to print in.

I've wondered about this too. I use the 8x10 plate to ask students what's the longest t-rex print the M2 can make. Are there big effects from having both x and y moving simultaneously? I haven't noticed any but my prints are usually printed on the x or y axis.

[benavery]

I've wondered about this too. I use the 8x10 plate to ask students what's the longest t-rex print the M2 can make. Are there big effects from having both x and y moving simultaneously? I haven't noticed any but my prints are usually printed on the x or y axis.

No noticeable effects. Even if you align a rectangular object with the axes, the infill and top/bottom fill generated by S3D will typically be at 45degrees anyhow. I'm looking at a hexagonal nut I printed, and all 6 sides look identical (2 of them would have been axis-aligned when printed, but I can't tell you which)

[jdacal]

I've gotten big prints to about a 1/4" of the edge, could probably have gone the rest of the way but haven't wanted to risk it.