I'm guessing that the plates are printed with ABS. I'm interested to see if ABS is strong enough and won't flex under the stresses of milling. You do have a large 3D printer, the parts look great so far. Please keep us updated.
This is a cool project/idea, looking forward to seeing how well it works. I think the plastic should be strong enough to handle most jobs.
They are actually printed in PLA which is more ridged than ABS but heat could be an issue with them - going to use some ABS spacers on the motors to deter that issue - hopefully.
Check out JimmyBuckets thread. You guys are going down the same path. I was very impressed with his first attempt at Gantry Plates. I would have thought bonding several thinner plates into a Laminate would be incredibly strong. Gray
They way the printer lays down plastic you can decide how thick you want the outer edge, how dense you want the inside and how many solid layers on top and bottom. The ones I designed were layed down with .35mm layer height with 4 layers of solid material on top and bottom. .35x4=1.4mm of solid PLA (plastic)...I also used 5 outer loops on everything...so all holes and shapes have .35x5=1.75mm this walls. In the areas between the solid and top layers we use infill...this can be defined by density. I used 50% infill. This basicly mean these areas have fill that is only 50% solid. This is a much heavier duty print than what I normally would do for mostly everything I make. Also, when the machine lays down layers they are 90 degrees of each other...so it is basicly the same idea as plywood. Hope that helps give people a better idea...if I didn't describe something correctly please feel free to correct me. Also the plates are 8mm thick.
I printer my plates 100% infill so did not worry about my perimeter thickness too much. Same goes with how many solid top and bottom layers. These are really strong - said strong as I can get them. I also upped my normal extruder temp to ensure a good bond. Printed at 220* C and printed fairly slow 50 mm/s I believe.
Chris did you check the flex in the plates? You can clamp one on the edge of a table and start hanging weights on it, while measuring the deflection with a straight edge. I guess it will give you a good indication of what to expect. I just printed 2 router mounts in ABS for a Makita trimmer router, they seem to be very solid. I looked into the smoothie board and found that the Amps are too low for nema 23 steppers. See Mark's OX build discussion page 46 for more about that.
I am also interested in the flex of the plates. What thickness are you printing these at? Also, how many hours did it take?
I printed them at 6mm and it took about 4 hours for the main plates to print - I was not pushing the speed to much during the print. I could not bend the plates at all side to side, I printed in PLA which is a very rigid plastic. When I assembled the gantry and had it attached to the rails (see updated pictures) I did notice that they would twist a little if one end was held and the other end was pushed forward or back. I do not think that will be a problem though once the belts are install not allowing that to occur. I do not have anything to compare to but surely mdf plates would flex in the same manner, although I am sure aluminum plates would not!
That is what I am afraid of - oh well, I already have the board - going to see what it can do - if it cannot handle it I will get something else - probably a GShield.
I did find that if I try to do heavyer cutting like aluminum that the plates do flex on me, especially the X / Z assembly.