@Nicholas
I *think* (and I may well be wrong) that the bolts that fasten the motors down go through the plywood that is at the very bottom of the assembly. Put another way, they fasten below the motors.
What I'm suggesting is having the motors stay below the build plate, but bring the mounting screws up rather than down. They would fasten to the "build plate" plywood. With double thick wood, countersinking the bolt heads would be fairly easy.
@Jason
As you may gather, I've gone through a lot of gyrations on the arms. I finally decided that drilling a pair of holes in a solid bar was simple enough that I'd go that way. Aluminum is pretty stiff, and it's also fairly cheap. If you are doing PLA, I'd bet that polycarbonate would be fine no matter what you did for heating. The other printed parts in the system will have trouble before it does.
I *think* (and I may well be wrong) that the bolts that fasten the motors down go through the plywood that is at the very bottom of the assembly. Put another way, they fasten below the motors.
What I'm suggesting is having the motors stay below the build plate, but bring the mounting screws up rather than down. They would fasten to the "build plate" plywood. With double thick wood, countersinking the bolt heads would be fairly easy.
@Jason
As you may gather, I've gone through a lot of gyrations on the arms. I finally decided that drilling a pair of holes in a solid bar was simple enough that I'd go that way. Aluminum is pretty stiff, and it's also fairly cheap. If you are doing PLA, I'd bet that polycarbonate would be fine no matter what you did for heating. The other printed parts in the system will have trouble before it does.