Design Revisions Cont.

I just picked up a dual-extruder 3D printer, so I think I can make a front nameplate for Sketchybot that’s dual extruded instead of making that insert I proposed in my last post.

I imagine using black PLA everywhere but the areas where the text is – the text should be printed in transparent or white PLA.

Generating the different solid models required for this idea will be done by applying boolean operations to bodies comprised of extruded splines. This is going to torture my CPU – so that will be fun!

I also want to make a new Back Cover for the bot. The slotted laser cut acrylic sheet I originally designed was very difficult secure in place, and bending it into the correct shape with a heat gun was difficult by hand. It looked like this prior to being bent into shape-

I could heat the sheet in an oven and then place it onto a CNC-cut form, but that would be way too much effort for little return.

Instead, the new Back Cover will be entirely 3D printed. Pending any last minute changes, it should look like this –

I will need to use threaded brass inserts to secure this Back Cover to the Side Plates, since I will not be able to hold a Nylock nut in place, while fastening everything together. I could inset the nuts inside hexagon cut-extrudes, but I’d be worried about such a feature rounding out.

Electronics Update

I finally got my 24V step-down converter wired up! I have since then installed the LED strip inside the 3D printed front name-plate. It looks like this –

From afar, the lights really wash out all the text… I’d like to avoid that.

Up close, or at a few particular angles, the text looks great – but I want it to always look great!

So I’m thinking that I’ll 3D print an insert that’ll slide inside the cavity in the front name-plate piece.

Here’s a short demonstration of what the part will look like in the assembly –

So hopefully this new component helps out. I’m going to print it of black PLA with a high shell-count and 40% infill, so most of the light shines through the text. If this works, my next step will be to sand down the front surface of the name-plate and spray some gloss paint on it. I’d probably mask off the letters for this process, but a quick test could determine if that’s truly necessary.

A new GRBL shield and some low profile stepper motors were ordered today! I’ll have those parts installed by Tuesday, I am just really hoping that I don’t need to modify GRBL firmware that much when I get the new board.