Printing Machine Stock Removal Arms

thingiverse

Alright makers out there that can lend me a hand! I'm attempting to add pneumatic tubes into this part (The magenta in the wireframe), but when printing, they're filling with what I suspect is support material. I'm utilizing Simplify 3D, which works great for scaling and such, yet I'm struggling to figure out how to maintain those tubes hollow. These custom parts were made to replace some faulty PVC items on our machine that kept breaking down. So far, so good. The originals worked just fine, but I've decided to enhance them with a pneumatic lifting system, which is why I needed to add these pneumatic tubes in the first place. Next up is installing pneumatic tunnels and guiding them towards the pickup tips, then using a pulse-jet of air to break loose the printed sheets from the table for easier removal.