…code, cg, electronics, 3d printing…

I thought it would be a good experiment to try 3d printing something ‘more complex’ on my Replicator:  Enter the “Botmobile”

• Assembly Instructions.
• Files on Thingiverse.

First off, some pics!

Here’s all the 3d parts printed out, plus the electronics kit… which is no longer available in the Makerbot Store:  I talked with Makerbot support, they’ve discontinued it

And here’s the finished thing:

It was quite a process to get everything printed out, but overall, really enjoyable and I didn’t encounter any problems.  I printed everything out in black ABS, and then spray-painted the body and wheels cherry-red (same as the previous bowl I printed).  The assembly went off without a hitch, and other than having to slightly adjust the front steering servo, it started driving right away.  Overall, I wouldn’t call it a ‘high performance’ RC vehicle:  Already the gearbox is starting to strip (and I can’t figure out why, it seemed pretty tight when assembled), and the front wheels hit the battery-box when turning sharp (underneath, in the middle) if you don’t trim it right.   But it does drive around and steer, so mission accomplished there.

Everyone’s been asking how long it took to print.  I’ve had little luck successfully using the ‘accelerated’ setting on my Replicator, so it’s all been ‘standard print times’.  There were multiple files to print, here’s the time estimates for each:

• Windshield: 1h 7 min
• Rear Axel: 1h 34 min
• Back half of body: 4h 51 min
• Front half of body: 5h 22 min
• Gearbox: 2h 21 min
• Interior seats: 2h 57 min
• Front steering assembly: 1h 44 min
• Wheels (all four): 8h 41 min

So that adds up to 28 hours 37 minutes.  It didn’t seem that long though:  Most of the long prints I did overnight:  I hooked up the printer to my a light timer (the type you plug your lights into when you go on vacation so you can turn them on\off at a certain time), and would set it to auto-turn off the printer about half hour after the print should finished.  Worked perfectly every time, didn’t have any misprints.

As of the time I printed it, I’m one of four people who have ‘made it’ on Thingiverse.  So it’s a unique feeling to know that… not many people on the planet have a 3d-printed RC car.  Here’s a few more pics:

I’ve finally successfully printed a life-sized sledgehammer.  It doesn’t look half bad:

It also took 7.5 hours to print with 5% infill.  But worth it?  Yes.  Next is spray-paint.

Also been printing some custom beer-bottle openers, based on this thing:

I created the text & modified the mesh in Maya, exported as obj, converted to stl via MeshLab, and converted to gcode in ReplicatorG.  Made the text black with a Sharpie 😉

I’ve had it in the back of my head for a long time to make some type of lamp with LED’s.  And with the arrival of the Ostrich Egg-Bot and its diamond etcher, I had the concept of spray-painting some egg-like object, and etching away a pattern to let light through.  Below is my first attempt at such a thing. Did it work out just like I had envisioned?  Not quite.  But it was a great learning experience, and I’m in a much better place if I decide to do it again.

The finished product

I started out by purchasing a simple glass vase at the dollar-store, drilling a hole through its base for the power-cord (which was surprisingly hard even with the special ‘glass drillable bits’ I purchased).  I spray-painted it matte-black on the bottom, and sort of faded the paint up the side so it’d be more transparent at the top.  I designed a simple pattern in Inkscape, which the Ostrich Eggo-bot then etched onto the now-painted glass vase:

Etching in progress...

Upon completion of that, I selected four LED’s for the inside of of the light:  A high-power blue for the middle, and four high-power red’s that would shine out the sides.  My hope was the red LED’s would show off the etching.  As a mounting platform for the LED’s I cut a round piece of wood from a piece of scrap plywood, then drilled holes in it for the LED leads, and the power-cable.  I grabbed an old wall-wart, cut off the end, and threaded it through the hole in the vase and my wood disk. I wired that into a breadboard with appropriate resistors:

Breadboard!

Finding success there, I hot-glued the led’s into the wood disk:

From there I started the process of soldering the resistors to the positive leads, twisting all the positive leads together and soldering to the power-cord.  I used black electrical tape as a simple barrier between the positive and negative leads when I soldered second:

Plugged it in to make sure it worked….

Pulled the power-cord back into the vase (it was a tight fit, so friction is enough to hold it in place) and had the finished product:

Things learned:

• If I do this again, I’ll put the etching lower on the lamp:  It will be easier to see and show-off.
• Need to get LED’s that have a wider angle:  These are fairly focused, so don’t diffuse as much in the lamp as I’d like.
• The lines of the etching itself are very thin:  I’d find a way to make the etched-away areas larger.