After completing my very first CNC build, I am in the process of redesigning the whole thing. Now that I have a CNC router, I can make much better components and design a better machine.
Original build thread: http://www.cnczone.com/forums/cnc-wo...cnc-build.html
Based on input from Ger21, I am designing all the components of the gantry as torsion boxes to maximize the performance of MDF. So far everything is going to be 3/4" MDF (skins and grid pieces).
Here's what I have so far for the Y axis. It's going to be 4" thick (.75" skins and a 2.5" grid).
The second picture shows where I plan on embedding m8 bolts into the frame using epoxy (there will be a second set of bolts in the skin piece that isn't shown, for a total of 4 bolts). Right now the plan is to use through-hole construction on the gantry uprights to bolt to the y axis.
I'd appreciate any input you guys have about my progress so far. I'd especially like some input on my embedded bolts on the y axis to fasten the y to the uprights. It's the best way I could think of to avoid threading into MDF and being able to disassemble the machine (looking to buy a house so I need to be able to take it apart and transport it at some point).
I also had another question I've been pondering. What, if any, difference is there between a 2.25" thick MDF torsion box vs 3 3/4" MDF sheets glued together to make a solid 2.25" thick piece? Ger21 recommended a 2" to 3" thickness for the uprights. I'm thinking if it makes no difference structurally, it's easier to glue together 3 sheets of MDF than do a torsion box assembly.