Make your creations scurry around with these handy little windup walkers, store.makerbot.com/makerbot-windup-walkers.html

One day Bre walked into the Workshop and declared "everything on Thingiverse should be able to walk". And now it can!

With the Windup Walker 5 pack you will have your ideas scurrying off into the sunset before you can say sarsaparilla.

To help get you started we've created charming walking derivatives of R. Maker and his friend the TARDIS.

See them in action: youtu.be/O5dVQayw9Nc

R. Maker is a derivative of: thingiverse.com/thing:11654

TARDIS is a derivative of: thingiverse.com/thing:13109

This is a spring designed for 3d printing.

Watch the video to see it in action!
youtube.com/watch?v=UxwbQSMbEIA

The more you scale the spring, the smaller the spring constant.

Increasing your filament width increases the spring constant.

The spring can be used in tension or compression, but it must be fairly short with comparatively thick filament width to be used in compression.

It can be made extremely flexible and it is very fun to play with.

It's form was discovered by accident, as it was originally auto generated support for the middle of a hollow cylinder.

I'm still perfecting the design but it works quite well in it's current state.

I will be uploading different sizes (and source files shortly) over the next few days.

The spring was prototyped on a Fablicator.
Fablicator.com

I'm trying to make a mind controlled tentacle and this is where I'm at so far.

Right now, the ball and socket joints are a little too loose, and the movement isn't very good (partly due to the weight of the parts).

Also the sockets are a little stiff and fragile when printed with PLA

Once all that is sorted, I'll hook it up to some servos and the obligatory Arduino.

Video of it "working": youtu.be/EVMatHNgC6s

At long last, everyone in the world (ok everyone who has access to a 3d printer) can have their own bust of America's greatest entertainer and statesman, Stephen Colbert.

Even better, you can use this model and your favorite 3d modeling software to add Mr. Colbert's face to objects which were formerly lacking in Colbert heads, like bannisters, umbrella handles, toothpaste squeezers, and rabbits. (To name a few.)

Made with a Polhemus 3d scanner at the Colbert set on 6/6/2011.

Full writeup on my blog at: eclecti.cc/hardware/physical-keygen-duplicating-house-keys-on-a-3d-printer

It occurred to me recently that I had printed almost nothing actually useful on my RepRap 3D printer, aside from parts to improve on or build more RepRaps. I am rectifying that with this project. The goal here is to generate working house keys by inputing the key code of the lock into a parametric OpenSCAD model. Instead of having to explain to my landlord how I ended up with a wedge of plastic jammed in my front door, I ordered a box of (well) used locks and latches from eBay to experiment on. Luckily, the lot includes both Kwikset KW1 and Schlage SC1 locks, which are the two most commonly found in the US. I created an SC1 model to start with, but I’ll probably make a KW1 soon.

EDIT: I uploaded a KW1 model as well.

Designing the key model was actually pretty straightforward. I measured a key with a ruler and calipers and created an approximate model of it that is reasonably easy to print. I then got pin depth specifications and parametrically differenced them out of the model. To generate new keys, you can just edit the last line of the file and enter in the key code for your key. If the code isn’t written on the key, you can measure the height of each bit and compare to the numbers in the Root Depth column on the aforementioned pin depth site. Perhaps more nefariously, you could implement something like SNEAKEY to generate key codes without physically measuring the key.

This is a bracket I made for mounting an adjustable desk top positioner to my drafting table. Besides being pretty, it keeps the positioner rod from hitting the lip of my table.

Unfortunately, I misplaced the nice brass screws before I got my brackets painted like brass. For now, I had to hold it in place while taking the photo.

What can I say? I've never been able to draw anything with an Etch-a-Sketch. I won this one in a Christmas gift exchange some years ago and hung onto it with the idea that someday I'd CNC it.

The stepper motors are 7.5 degree Airpax steppers I got surplus many years ago. It turns out those mounting ears are actually NEMA 23 compatible so this should work unmodified with "square" steppers as well. The 7.5 degree steps led me to make the most aggressive gear reduction I could fit in the available space. They take me to about 0.15mm (6 mil) steps with half-stepping.

The stepper drivers are L297+L298 almost straight out of the appnote. They're built on a piece of copper clad with a combination of dead-bug and Manhattan prototyping. I bought all the parts years ago and never got around to etching PCBs. Those flyback diodes are ridiculously oversized because I didn't know better.

I chose reprap.org/wiki/Teacup_Firmware because of the builtin gcode interpreter. That saved me from having to integrate with any desktop software. I ported it to the AT90USBKEY you see in the picture and added support for LUFA-based serial right in the AVR. (I already had the AT90USBKEY or I would have just bought an Arduino!)

It easily goes 8000mm/min (which is how fast the pictured spiral was drawn). Given the torque and the large step size I suspect it could go fast enough to melt the stylus if you cared to.

The gears (as printed and uploaded) have slightly too much backlash. The "exact" fit was too tight so I backed off by 1mm which was way too much. They're derived from thingiverse.com/thing:5505 .

The spiral was drawn in Inkscape and converted to gcode for Unicorn with thingiverse.com/thing:5986 . I plan to modify that to make more Etch-a-Sketch friendly output.

Video: youtube.com/watch?v=6UV05jmrK7k

This is going to be a reaaaal long one, folks. Better buckle up your thingibelts.

I believe this project is complete. There are workable, though probably not ideal, solutions to all major problems. The code and mount are both perfectly usable.

Youtube videos availabe at:
youtube.com/watch?v=tSp8FKgoY8k
youtube.com/watch?v=mv3wxvR8w5A
New! youtube.com/watch?v=XafKYIxlgBk

For people who just want the short version to go with the photos: Of course when I thought about what to print first, I thought the classic 20mm cube, but in a checkerboard pattern.

Setting the head offsets in the software exactly is important, and not difficult, but I couldn't dial it in during the course of this project as every time I'd set it I'd change something to unset it again. That's the only reason many of the prints are overlapping in odd ways.

Any ooze tends to accumulate at the offset position and eventually get rolled into the model, making a mess. The final update to the script has solved this with some ooze-controlling reversal, which I didn't bother to get dialed in exactly before closing this file. :)


THE STORY:

On Friday, it struck me I had a MK5 hot end just sitting here in a box, unusued, and I thought -- wouldn't two extruders in one machine be a neat idea? You could print two colors together, or you could use one to print some kind of support material; who knows what that might be. I knew you could dissolve PLA with toxic chemicals, but I also knew I'd never be allowed to play with toxic chemicals; I'm not even really allowed to print ABS.

I decided I would have the entire project complete, from conception to completion, done by the end of the weekend. You might have noticed my rash of part releases.

Well, I missed it by /that/ much, but it turns out to be good news. MBI on Monday announced dissolvable plastic ( store.makerbot.com/makerbot-pva.html )... which means now we know what to use as support material. The timing could not be more perfect. In addition, this makes the perfect thing to do with your old MK5 once you also have a shiny new MK6... Or maybe you bought a third-party hot end, like one of the excellent ones from Makergear.com, and now you can get your old stock hot end out of its drawer and use it again.

Now, when I say completion, I don't mean this project is finished, oh no. There's a very long list of little things to fix or change, and a short list of big things to fix or change.

CURRENT MAJOR PROBLEMS:
* The bolts on the build platform mean your print area can be greatly reduced --
-- SOLVED... switching to the ABP cures this problem neatly.
* Need a brilliant way to assure both heads are on the same Z-plane physically.
-- SOLVED... not exactly brilliant, but the new mount is easily adjustable.


CURRENT MINOR PROBLEMS:
* It would be helpful to people who do not have the option of switching to the ABP to have a mount where the heads are aligned 90 degrees offset from this.
* Some kind of quick-release mount for the second extruder would be nice. Maybe there would be a way to work Z-height adjustment into it.
-- SOLVED: V2 mount is easy to remove and install separately.
* The closer the two heads together can be brought together, the less loss of build area will happen, bolts or no bolts.
* It should be theoretically possible to drive two heads from one EC; if I blow up my other MOSFET I may have to pursue this possibility myself. This would require some hacking of RepG at the least and probably the firmware too.
* The software could use many improvements; what I've given here is a workable starting point to build from.


TRIALS AND TRIBULATIONS:

I nearly hit my goal of having it all wrapped up by the weekend. I missed it because the 608-based Wade's style extruder I built off the STLs I uploaded over the weekend: thingiverse.com/thing:6492 did not work. It wouldn't push plastic.

You might think that meant it worked OK, I just couldn't demo it, and you'd be right. At this point, I had two stepper extruders working in concert but I couldn't make a test print, because one wouldn't push plastic. I felt like I couldn't put up the thingiverse entry until I could make the thumbnail a two-tone print.

So, this set me back a whole day. Well, this, and the fact that I have to work for a living, still...

I decided the problem was the bolt I hobbed wasn't nearly as good as Makerbot's MK5 drive gear thingy: store.makerbot.com/mk5-drive-gear.html ... while the MBI delrin extruder is of questionable value, this gear is the /bomb/. I tried hobbing another bolt, but I just couldn't make one that worked.

An additional problem is that the design STLs I posted have the wrong value for the filament distance from the hobbed bolt, making it add a lot of friction and nearly impossible to get in the hole.

So I decided that other people would want to use it with the DC motor, and I might as well buckle down and replace my 2nd stepper extruder with a DC extruder, temporarily. I couldn't find a 606 bearing on such short notice, but I've seen plenty of people run without it, so I made do.

It turned out this introduced a new problem. While I was fortunate to find the MBI ReplicatorG and Firmware supported everything I wanted to do /already/, which was REALLY NICE, THANKS GUYS!! ... I found there was a bug or oversight in the drivers for the stepper extruder version; if you use them, they will just delete any commands that drive a DC motor. So if you have one of each like I do for the moment, it won't run the DC motor.

Fortunately, this was about a ten minute fix in the RepG code, which I'm getting all too familiar with. (Patch will be supplied below if it isn't already when I hit PUBLISH).

Next the DC motor stopped responding (probably just needed a reboot, honestly), and in my naieve efforts to fix it, the mosfet blew up, literally; photo attached. I couldn't get it to switch to the second mosfet in the legitimate fashion, RepG wouldn't recognize the extruder to set it's eeprom... So I hardcoded the change in a copy of the firmware and uploaded it - finally the DC motor was back online and I had only lost about two hours...

Once I finally got it all up and running, testing my software proved to have it's own fun points, too. First I got the offsets and everything all backwards, and nearly drove my print heads into the bolts many times. Once I finally got it completely sorted, the first test print I discovered a really fun thing -- if your print heads are off in the Z direction by a tiny amount, that's OK. But if the lower one prints last, it'll rip the tops off the taller one's print.
EDIT: I actually think the cause of the destroyed print in the photo and the other messy prints are all down to the shadow print/ooze that develops and tends to roll into the model. The latest version of the script provides ooze-combatance for this reason.

As you can see, I didn't find a way to measure my Y offset so I guessed 0 on the first print, the one with the missing tops, and I was wrong, so I adjusted it for the second print... in the wrong direction! Doh! It'll be fixed for any future photos, I hope. The X offset is easy enough to measure since that's the way the heads are aligned in my build. If you have the ABP, having them aligned in X like this is good 'cause then there are no worries about bolts AND you might be able to hack the ABP to get back any lost print area. It's a win-win.

But I'm not running the ABP right now, so I need to watch my bolts like a hawk and it would have been better if my mount has the heads aligned in Y instead of X - rotated 90 degrees.

UPDATE (2011-02-23):

I got one print off today before the DC motor stopped running. The LED on the mosfet comes on when I tell it to run, so I'm not sure what the problem could be. I still have the relay I built to run it on the Thing O Matic extruder controller, but it's on a cupcake EC and I'm surprised to find it fails there, too - have other people had that problem?

I also switched out my build platform so the bolts would run the other way.

I swapped in a different DC motor and it works, but the DC motor overall oozes much more and takes much longer to start again than the stepper motor, so the grey parts in my prints are coming out looking somewhat lousy.

Otherwise, you can see it's working well and I fixed my Y-offset by just adding 1/2 the difference between the top and bottom parts sizes to it.

Next I added springs to the front extruder, assuming I only need to be able to adjust one to match the fixed one. This helped my prints a lot -- part of the problem with the greyparts is they weren't getting good stick on the 1st layer. Now both materials are getting good stick. Changing out for the springs changed my X+Y offsets by a very small amount, but that's easy to measure using this test cube.

The springs seem like a workable solution, -- I'm surprised the thing is not wobbly, but I used very strong springs, so...

UPDATE (2011-02-24): Added new mount .STL; this one should be a good way to solve both the quick-remove problem and the z-alignment problem, at the cost of drilling 2-4 new holes into your stock acrylic bridge. I'm going to have to figure out how to get replacement lasercuts parts after these experiments are finalized, I bet.

Since the STLs aren't rendering here, you can see the new mount here: thingiverse.com/thing:6517 until I have a photo of the printed thing.

While adjusting my printer to print the part (I decided to lower the spring-loaded head down as low as I could to get the other out of the way, and just print in 1 material) I found there's an easy way to adjust the springs tension - while the end is cold and full of filament, simply turn the motor back a few steps (by hand?) and it will raise the end up, allowing you to easily twirl the nuts to your desired location, before lowering it back down. Youtube video here: youtube.com/watch?v=gJStB65cSvA

I am greatly looking forward to seeing the postman today, as he'll have my order from Makerbot with the dissolvable plastic, as well as the parts I will need to rebuild my stepper extruder properly, and eliminate the DC extruder.

I finished printing the new mount. Checking in the control panel after the print revealed to my pleasure that the /other/ extruder, the one I didn't use in the print, was at a nice cool 30degrees still.

I wonder if I should have designed the mount to use the existing bolts on the front of the bridge. I guess I'd like 4 bolts for it though, so this is probably OK, even if the other way means less destruction.

If the big 'shadows' on my dual-color prints didn't make it clear I'm not doing anything to combat ooze presently, the print of this new mount will...

UPDATE: (2011-02-25)

My box from Makerbot Industries showed up today. It had 4lbs of PVA, plus a handful of 606 bearings and those wonderful MK5 drive gears. So I rebuilt my second stepper extruder, and put on the new mount all at the same time.

The new mount works as advertised; it makes leveling much easier, and taking off the whole second extruder when you want to go back to 'normal' a snap. I recommend it. It also makes mounting everything a lot easier.

It does require you to drill 4 holes in your acrylic bridge. Drilling acrylic is supposed to be very tricky. I actually used a dremel instead of a drill, with a bit I dunno the name of, but I'll post a photo. I went slow, it cut like butter; I wasn't worried about cracking it at any point. My room does still have the faint aroma of my 8th grade shop class, where we all made acrylic salad spoons. Mom still uses it, 20 years later.

The only real problem I have remaining is the ooze creating a mess that frequently gets rolled into the model and turns it into a mess. Since I've got two functioning stepper extruders now, I'm working on additions to my combine script to handle reversing the filament feed in a sensible way when switching off heads. There will be a new version of the script up soon, and new photos.

If I solve the ooze issue to my satisfaction, I'll be ready to mark this WIP as done.

.... and I have now, in the latest version of the script. I'll write up full documentation under INSTRUCTIONS and call this finished.

Thanks for reading... and good luck with your dual-extruder printing!!




Once again, I owe thanks to everyone on IRC Freenode, especially Kliment this time for his encyclopedic knowledge of Gcodes. And thanks to RepG coders for having done most of the work. And thanks to my very patient fiance.

Here's my first attempt at 3-d modeling. The Banana slug is one of the most unusual creatures living in the Pacific Northwest (U.S.). Since my transplant here a decade ago, I am still amazed at how big they can get - up to 8 inches. I've made ceramic slugs and crocheted slugs, so a plastic one seemed like fun.

I added embossed hearts on the sides to make it an actual companion cube. ;)

A rice mold for making Mario themed rice balls. I created these for use in bento boxes, which I've been blogging here: kellbot.com/category/bento

These each use a little less than a 1/4 cup (dry) Japanese sushi rice.

A modified version of this could be done on a Makerbot or 3D printer, if anyone wants to attempt it.

I fixed it so it is right-way-up and scaled correctly.

A hook with a bearing to suspend a basket of plastic to feed a RepRap machine. Full details in my blog: hydraraptor.blogspot.com/2008/11/sky-hook.html

This is a PostScript program to generate optical encoder wheels (suitable for printing out on a transparency). Unlike similar programs, it is highly flexible and has many features, such as:
-Correct inside and outside diameters, regardless of line width.
-Quadrature capabilities, with adjustable phase difference.
-Automatic scaling of text size.
-Optional index track, with adjustable size or automatic fitting to segment size.
-Automatic page filling with cutting allowances.
-Most features can be turned on or off.

These DIY molded rubber wheels might be perfect for your next robot.

The mold rubber used was Smooth-On part # PMC-121/30 Dry.

The alternate wheel hub will hold the rubber more securely but may be more difficult to print on some printers. The aluminum hub to attach to the motor is not included, but this should work.

More robot related information at iheartrobotics.com

Party Poppers - little things that go bang when you pull the string, not the other kind of popper. Beat the New Year Party Popper Ambush with this cunning contraption that can let the paper shrapnel of nine 28mm PP's rip simultaneously - or go on the celebratory offensive and visit a party full of very surprised friends!

Voltage regulated tea :)

I couldn't get the typical tea infuser holes to print nicely (too small), so I used a different approach: a large hole on the back covered by a grid that lets the water in and out while keeping the tea leaves inside.

Warning: this code is pretty rough, but it works!

This project is a derivative of the code originally written by Allan Ecker, found at:

thingiverse.com/thing:747

thingiverse.com/thing:783

thingiverse.com/thing:849

Code will continue to be updated at github.com/davemenninger/Parametric-GCode

I will try to remember to re-upload the latest versions of the code here on Thingiverse as it changes.

This is the second half of my openscad.org gear sets.

I couldn't get the top and bottom parts of the double helical to union properly, so I ended up offsetting the bottom piece by 0.1mm :( It skeins and prints fine though.

This thing is part of a set:
- spur gears: thingiverse.com/thing:1336

UPDATE: I'm printing some gears and noticed a couple mistakes on the openSCAD script: the variable 'orientation' wasn't doing anything and the value 'extrudeInDiam' was in fact being used as radius. They're both fixed now and I uploaded a new version of the script.

4h40 m
136mm

Even though there are lots of great gears on thingiverse, I couldn't resist the urge to model some too :)

The combinations of parameters are too many to upload an STL for each, so I just picked a few.

I also made a version for helical gears: thingiverse.com/thing:1339

I printed these up 5.53 hours. Assembled with no tools - way fun way to use up the last bit of ABS black I had in an old cartridge !
I think I could have printed the set as a single piece instead of 28 .STLs on a single platen (chain would have been different, and I could get away with it because I use H2O soluble support material)

Better Living with MakerBot, Episode 2
You probably all know this situation:
You're supposed to ref a soccer game in less than 1/2 an hour and you cannot find your whistle. You're screwed!

But from now on you're out of trouble: Fire up your trusty MakerBot and print a new whistle in 26 minutes!

This object prints the pea right inside the whistle. Since the pea is connected to the rest of the object only at one tiny point, it's quite easy to break it loose after printing with a small screw driver or tweezers.

I probably pushing luck a little bit with bridging the top layer. So far I printed the whistle twice without problems.

As always, I added the object as .obj file (wavefront), which can be imported into AOI and Blender.

The gcode file is the one I used to print the whistle on the image. The gcode file contains an experimental raft with additional "blobs" on the second (interface) layer.
You might want to generate your own gcode file with skeinforge settings, tested with your MakerBot. Be sure to setup Skeinforge to create an (almost) watertight object, since the whistle won't whistle if it's full of holes...

[Update]
I added a second version of the whistle. "Whistle_v2" is an attempt to fine tune the object a little bit. My brother (he's a pipe organ builder) gave me some tips how to optimize the whistles mouth. Whistle v2 should start whistle with less airflow than v1 and thus be (somewhat) less loud. I also downsized the pea a little bit and changed the shape of the lanyard loop.

Whistle v1 is still available for reference and also since it's more "tested"...

Since you blow the whistle with your mouth, be aware of possible problems concerning "food safety" of printed plastic. See the blog post "For foodies out there" ( blog.thingiverse.com/2009/09/13/for-foodies-out-there/ ) for more information.

This is a 4-pin tumbler lock with a key and display case. Insert the key and turn clockwise to get a smiley face!

It's a geared calling card! Two slots in the top layer display different information as you turn the smaller gear, and a little window lets you watch the gears mesh.

A calling card with working planetary gears. Astound your friends, frustrate your nemisii.

(Update: I've moved the gears slightly to the right, reducing the number of cut parts to assemble.)

This is the design we used for the first batch of MakerBots. These are the lasercut design files you will need to make your own if you have access to a laser cutter.

For Mothers day I made my mom a set of earings that double as a working planetary gear.

...sorry for the pun in the name.

Make a little art with you business cards

See our video at adafruit.com/blog/2009/05/25/adafruit-business-cards-laser-cut-spirograph-cards/