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This weekend I ran out of ABS. Thankfully, a month or two ago I predicted that this would happen and bought a spool of 3mm PLA from reprapsource.com . If you do some reading, you'll see that PLA has a lot going for it: It's biodegradable. It has virtually no problems with warping. The hot plastic smells like pancakes! Could all those things be true? Since my PLA came on a plastic spool, and that spool didn't fit in my MakerBot filament spindle , I had to improvise. I took the bottom half of my spindle out of the box and removed three of the vertical struts. That let me set the new spool on the Lazy Susan . Nice, right? Well, revision one didn't work so well. The fix was to add some sticks to extend the diameter of the base (at least until more of the filament has been used) and then to loop it through a guide above the spool so that it wouldn't catch on the sticks. Success! I'm now continuing the process of upgrading my bot by building a Z-Rider ...

This weekend I finished hooking up my MakerBot Cupcake CNC to use Bluetooth. This has been done before. However, I've not found any instructions for setting up ReplicatorG (aka RepG) to use a Bluetooth serial connection under Ubuntu. I'm using a BlueSMiRF from SparkFun and hooking it up to a Gen3 RepRap motherboard. This is slightly more complicated to use than using a Bluetooth Mate because the pin-out does not match the TTL serial header on the RepRap motherboard. Paeae Technologies has a nice tutorial for using a BlueSMiRF . There's also a nice tutorial for using a Bluetooth Mate on the MakerBot wiki. If you use a BlueSMiRF like me, I recommend using short pieces of wire to attach the BlueSMiRF to the female header. It's easier to do than bending the pins like Paeae Technologies suggests. Also, you can see that I have the RTS-O pin disconnected. Although I didn't experience any problems, the Paeae Technologies tutorial reports that leaving it connected c...

This is my Android-powered, automated cat feeder: The attached HTC Magic is running SL4A and provides scheduled and on demand feeding as well as an MJPEG webcam feed. Feeding is triggered via Bluetooth. The Arduino is hooked up to a SparkFun BlueSMiRF and a simple relay circuit I made on perfboard for powering the motor on and off. The brackets and food chute were designed in SketchUp and printed on my MakerBot . You can find all the SKPs, STLs, schematic, and parts list on Thingiverse . Here's the 50 odd lines of Python code running on the phone via SL4A that make the magic happen: import android # See http://android-scripting.googlecode.com/ import gsd # See http://getshitdone.googlecode.com/ import socket import threading import time def feed(droid): droid.toggleBluetoothState(True) droid.bluetoothConnect('00001101-0000-1000-8000-00805F9B34FB', '00:06:66:04:b2:07') droid.bluetoothWrite('f') class Server(gsd.App): def __init__(s...

There is a similar tutorial to this one that uses Adobe Illustrator . However, Inkscape is a great, free, opensource vector graphics editor. Yesterday I learned how to use it to go from a photo to a 2D drawing and from that to a 3D extruded version of that drawing and finally to a real live object. Laura is going as Rachel from Glee this year for Halloween. To complete the outfit, she wanted a "Finn" necklace like the one Rachel is apparently wearing this season I opened the picture of the necklace in Inkscape, traced it with the Bezier curve tool, cleaned it up a bit, then selected and deleted the image I traced over. The next step was exporting a DXF. The DXFs exported by Inkscape don't seem to work with OpenSCAD. Instead, I had to install an extension called Better Better DXF Output . Download the zip and extract it into the extensions folder for Inkscape. On Ubuntu Lucid, the extension should be extracted to /usr/share/inkscape/extensions . Naturally, the fu...

I received my MakerBot upgrades last week and got a chance to put them through their paces this weekend. After having so much trouble with the original out-of-the-box setup, I'm so excited by the progress I made the past few days! Here's the list of things I suggest every MakerBot operator purchase: MakerBot filament spindle MK1 MakerBot heated build platform  with relay board MakerBot MK5 drive gear Aluminum idler (either  Brian Reifsnyder's  or one from MakerGear) MakerGear plastruder Here's the lot of them in action: The filament spindle is a great enhancement. It's nice to be (mostly) unconcerned with the filament getting tangled up and stopping a print midway through. I say mostly because so far I've had a couple jams. Only one actually caused the filament to strip. The jamming occurs because the filament slips off the spindle and gets wedged underneath. I suspect this problem will go away as I use more of the filament, but I'm trying to come up...

I received my deluxe MakerBot kit (batch 15) a couple weeks ago and had a blast putting it together. The instructions are quite well done (especially for the Cartesian robot, the extruder instructions could use a little work). I've been taking notes of all the little things I had to do to get it working. This is not a project for people that are afraid to break things or are expecting the ease or immediate satisfaction of building a Lego model. It's a complicated machine with lots of possible points of failure. That being said, it's super cool. First, if you're considering buying a MakerBot, or already have, take a look at this list of things you'll need in addition to the kit. I'll highlight a few things here that I found especially useful: spray on silicone lubricant (Amazon has good stuff ), good digital calipers and a small, metal ruler, a one-side razor scraper (get something with a handle), and an ISP programmer (e.g. a USBtinyISP ) for burning b...