Initially, I wanted to give the grates a finish that gave them a bit of a cast iron look. I took one of the failed PETG prints and tried sanding out the printing artifacts, but it became clear that this would also be a seriously tedious process. I would have to get filler into all the fine details without blocking the inset boxes, then sand everything without messing anything up. Any screw up and I’d be back to a new print and cutting out holes with an art knife. On top of that, this grate would never be produced in cast iron — the details would be too fragile. Even if successful, the grates would wind up pretending to be something they’re not. Better to be true to the medium and leave the printing artifacts there than to start over!
So I opted for a few coats of black paint, to take the gloss off the PETG. Then I moved to the final step, gluing the faces to their corresponding boxes with CA glue.
By now I should have learned to test everything before moving forward, right? Well I didn’t. Despite being a recommended adhesive, the CA glue didn’t take. All I got was two messy parts that stuck to everything except each other. Fortunately only one box/face was involved and although getting the CA glue off was tedious, it was removed without serious damage to either part.
From there, I went to a two-part, slow setting epoxy and sealed the faces to their corresponding boxes, and finally installed the grates!
I’m pretty confident that these will hold up, but if this version fails for whatever circumstance, I plan to do the third iteration in aluminum with a CNC router!