This is a cleaned up version of the printed clock we were able to make during Clockathon #2 last weekend. Thank you Makerbot and Bre for setting that up and hosting it, and thank you Ben for all the help, the awesome test print all set up, and the brilliant idea to back off one gear for the power drum.

It was ticking, powered by a weight that would only drop about 9" per twelve hour period, and included printed concentric shafts to support minute and hour hands on the face of the clock.

Here's some video: youtube.com/watch?v=AH4Tg2tIgfg
I had to inflict grievous harm to the code base at the time and have cleaned everything up since. See details below.

A negative space attempt at creating a frame that will support the shafts at every opportunity, while showing off the top half of each gear.

This is a subset of the parts needed for a full Test Jig #4, modified to try concentric metal bushing/shafts instead of bearings on those gears that need to support hands on the face of the clock.

For those of us with a Princess in our lives, and the need to be forgiven for the state of the living-room-slash-mad-scientist-laboratory and the ABS fumes... the ability to print a crown made of hearts can go a long way to securing continued forbearance. ;-)

Thank you MakeALot for the original of which this is just a quick hack.

A Peabody Award to replace the one Colbert "smashed" when he didn't win a new one the following year. Same idea as this thing: thingiverse.com/thing:9085

Wikipedia quote: en.wikipedia.org/wiki/The_Colbert_Report#Awards
In April 2008, The Colbert Report received a George F. Peabody Award recognizing its excellence in news and entertainment.[80] This award was last seen being "smashed" by Colbert in anger because he had not won the Peabody Award once again.

This one is better because it has his own face on it, and if he smashes it, he can just print a new one. :-D

Has the University of Georgia been slow in recognizing the importance of your contribution to television? Never understood why it wasn't your own mug on the award?

Thanks to the wonderful world of 3D fabrication, you can now print your very own Peabody Award today, in the privacy of your own studio!

;-)

The Bre Pettis Medal looked a little forlorn without some text around the edge... so I grabbed grokbeer's MakerBot Font module, and whipped up a little addition to the medal script.

The font module: thingiverse.com/thing:6844

Quick little OpenSCAD scrip to generate a roman emperor style coin or medal from a bust, using Bre's head as an example.

The script is public domain, not Bre's head which I believe he still needs, from time to time. ;-)

UPDATE: Renosis printed one out!

UPDATE: Added another version that:
a. Raises the profile up on a one millimeter ledge to make sure it generates several layers in Skeinforge before it starts to fill in the top.
b. Recesses the profile into the coin/medal, with a raised edge all around.

When I tried to make a throated worm screw ( thingiverse.com/derivative:9733 ), I ran into an issue: the thread profile was being extruded along the right curve in space, but there was no skewing of the profile to fit the curve.

You can see what I mean by comparing the images for this thing to the images for its parent. The tip of the thread remains vertical, no matter how the thread tapers or widens around the shaft. In the case of a throated worm screw, this meant that the worm gear would hit the parts of the profile that had not tapered out of the way properly.

Had to redo the polyhedron the whole thing rests on, and I took the opportunity to redo all the math vectorially, cuz it's cleaner that way. Also went ahead and made the shaft follow a curve defined by functions, like the thread does. More versatile, but we're not yet where the shaft could be a torus and the thread winds around it.

Now that I have this working in this stand-alone script, I need to work it back into the screw library ( thingiverse.com/thing:8793 ) and the throated worm screw will be a synch.

As I've just received my Thingomatic, however, (thanks MBI!) this might take a back seat to assembly, calibration, printing, etc... Sorry!

Ok, once you have an involute gear library AND a trapezoid thread library, you can easily make the simplest of worm drives, i.e. the non-throated kind.

Like all worm drives, the gear advances by one tooth for each revolution of the screw but with non-throated ones, there is only a single point of contact at any one time, and so torque and wear capabilities are limited.

UPDATE:
As I pointed out in the comments, AFAIK a trapezoidal profile for the worm screw is all you need to match the worm gear's involute.

To make them mesh, all I did was to make sure that:
1. the pitch is the same (distance from crest to crest),
2. the pressure angle of the gear is equal to the angle of the sides of the screw profile,
3. the distance between screw and gear is equal to the gear's radial pitch plus the screw's mid-profile radius, and
4. the twist on the gear is equal to the gear's pitch radius divided by the screw's mid profile radius, with a sign depending on the screw's handedness.

I added a negative-space module to the Thread Library today. This new module will create a negative space version of a thread, taking care of all the clearance calculations for you. All you need to do is pass it the same parameters as the thread it is meant to screw onto.

I also added a module to create a hexagonal nut that screws onto any threaded rod with the same parameters, but as a more interesting example, I chose to demo the new capability with a split lead nut.

Print and clamp the two parts over a lead screw or trapezoidal threaded rod, such as the ones found in many CNC machines, and attach them with two nuts & bolts.

The lead nut, if it is not allowed to rotate, will be forced in and out by the rotation of the lead screw ... but you all know CNC machines, you understand this already.

The images show the split lead nut, the negative space with the built-in chamfers, and a cut-away view of a hexagonal nut on a rod, to show the clearances.

This is the Thing page for the Screw Library I am working on. I could be talked into releasing it as Public Domain, but have left it as CC-BY-SA for now, at least until it's fully stabilized.

The latest code is available on GitHub here:

github.com/syvwlch/Thingiverse-Projects/tree/master/Threaded%20Library

Currently, the library allows you to create a threaded rod with a trapezoidal profile, like the Acme or metric lead screws that are so common in CNC machines.

The trapezoidThread module creates the rod along Z, centered in X and Y, but not in Z. Same logic as cylinders with center=false.

The parameters are the following:

length
// axial length of the threaded rod
// used to calculate how many turns to create
// the rod is NOT trimmed to this length!!!

pitch
// axial distance from crest to crest

pitchRadius
// radial distance from center to mid-profile

threadHeightToPitch
// ratio between profile height and pitch
// default value is 0.5

profileRatio
// ratio between raised profile and pitch
// default value is 0.5

threadAngle
// angle between the two faces of the thread, in degrees
// std value for Acme is 29 or for metric lead screw is 30
// default value is 30

RH
// true if thread winds clockwise along shaft
// i.e.follows the Right Hand Rule
// default value is true

clearance
// radial clearance, normalized to thread height
// default value is 0.1

backlash
// axial clearance, normalized to pitch
// default value is 0.1

stepsPerTurn
// number of facets to create per turn
// default value is 24

You can create a triangular profile thread by setting profileRatio to zero, but that is cumbersome. I will create a separate module for that and add it to this page, later.

UPDATE:

I have added a trapezoidThreadNegativeSpace module to create a negative space of a thread with the proper clearances to screw on, as long as you give it the same parameters. It can add two chamfered holes at the entries. It takes the following parameters on top of the ones needed for trapezoidThread:

length
// thickness of the part to be drilled out by this object

countersunk
// depth of the 45 degree chamfers, normalized to pitch
// default value is zero, no chamfer

I have also added a trapezoidNut module which uses the above negative space module to create a hexagonal lead nut with the right clearances to screw onto any thread that shares the same parameters. It takes the following additional parameters:

radius
// outer radius of the nut

Added a shaft component that follows the same set of equations you define for the thread. This is all overkill to define a nice, simple cylindrical threaded bolt, but I just couldn't let it rest. :-)

JelleAtProtospace pointed out that trapezoid screw thread are useful as well, e.g. to make a drivenut for the leadscrew threaded rods used in many CNC machines.

en.wikipedia.org/wiki/Trapezoidal_thread_forms

That sounded like a valuable and fairly simple modification, but I wasn't looking forward to modifying the polyhedron command at the heart of the module (adding each new vertex means adding several triangles and making sure they have the right winding order), but like anything else, you get used to it with practice and it really wasn't that bad.

It allows you to generate trapezoid screw threads that follow any set of equations you care to provide them, some of which will have more practical application that others. Some of these even look like they might make serviceable springs.

Again, because it generates the triangles directly via the polyhedron command, it's fast and lightweight.

freakinhuge suggested that a module to generate screw threads would be a nice-to-have. This is a variation on my previous polygon extrude/transform module in which the triangle is in the X-Z plane rather than the X-Y plane.

It allows you to generate screw threads that follow any set of equations you care to provide them.

Again, because it generates the triangles directly via the polyhedron command, it's fast and lightweight.

PS: the grayscale image is an anaglyph, look at it with red/blue glasses.

Extended the extrude/transform module so that the slices don't stay in the X-Y plane and are instead normal to the curve the extrusion follows.

Branched out from sines to include a parabolic function, for the demo object, making a kind of rose or knot.

The 3D shape is a little complicated, so I decided to create a mild anaglyph of it. The gray-scale image can be enjoyed with the naked eye, but if you have a pair of blue/red glasses lying around, you can see it in 3D!

Renosis pointed out that all this extrude/transform OpenSCAD business would render a lot faster (and produce smaller files) if I played directly with polygons. He's right.

I'm not sure how far I can take this new line of inquiry, but for a simple triangle, I can now extrude it along Z while translating and rotating in in the X-Y plane. The seams always match up, it's the exact minimum number of faces, and you can control how smooth you want the object to be directly, kinda like the $fn system variable.

The results compile instantly and render in minutes instead of hours, even for high polycounts, the STLs are tiny (183 kB) and import just fine in OpenSCAD.

I saw schmarty's clever Volumetric Tentacle Key Hook ( thingiverse.com/thing:8720 ), which struck me as right up the alley of my extrude-place-by-function doodles in OpenSCAD. When I looked at guru's original Volumetric Tentacle, I saw that indeed, he had used essentially the same methods but in Processing.

So I made a clone of his work, in OpenSCAD, just to show it could be done. OpenSCAD can do organic looking, there... you just have to be patient with the renders!

Alright, one more. This time, the placement and rotation of each extrusion of the base shape (here, a square, but again, it could be any 2-D shape) is controlled by one equation per axis, plus an equation for the scaling, for a total of seven functions you can define any way you like.

This particular shape has no practical application (altho... if we could print pasta?) but does show that OpenSCAD is fully able to make flowing, quasi-organic shapes.

It reminds me of the stuff I used to do, two/three years ago, with TopMod.

WilliamAAdams suggested, quite rightly, that the various extrusion parameters I've been doodling with could be controlled by functions... and I pointed out that the thing being extruded could be any 2D shape at all.

As a semi-practical application of these two ideas, this is a four-blade propeller made by extruding the union of a square and four rectangles while scaling that union according to the cosine of the extrusion height (with some twist thrown in, of course).

The layers are 1/4 mm thick.

Still exploring the possibilities of modifying a 2D primitive while extruding it. Added rotation in any axis to the previous scaling, which required adjusting the extrusion thickness to make sure the layers met.

The layers are 1/4 mm thick.

I was playing with extruding a changing shape, and this happened.

It's basically just two stacks of thin, skewed squares. It's surprising how much smoother the surface is if you twist the individual squares as you rotate them.

The layers are half a millimeter thick. The 40mm version is 40mm tall, and the 80mm version is, duh, 80mm tall.

UPDATE: Ran the 80mm version thru netfabb, which made it more than two thirds smaller.

This is the current release candidate for the Printable Clock Project. Many thanks to the many Thingiversians who have contributed over the last few weeks!

It is a work in progress and probably will need tweaking to even tick, let alone keep time. It currently has breakage issues in PLA, ABS is recommended.

Test Jig #2 was a major milestone, passing all four tests, featuring in the first video of a ticking printed escapement for this project ( prototribe.net/vidplay/testjig2.html )and serving as a development base for improvements from multiple Makers. If you want to print something that ticks, print Test Jig #2 with all the latest parts.

Test Jig #3 is intended to regroup all that progress into a new base camp for what we hope is the final push: an actual printed clock that keeps time. If you want to spend plastic and time in support of that goal, print Test Jig #3 and share with us what went right and what went wrong.

This current design is based on feedback from early adopters ssd, rustedrobot and TheRuttMeister, and in particular a very clever rustedrobot design for a ratcheting drum that rewinds the clock: thingiverse.com/thing:8555 Special thanks to Renosis for rendering gears 02 thru 07 on his machine last night when mine was not up to the challenge!

I've uploaded a snapshot of the code which generated these parts to this page, but the best place to find the latest and greatest is on github:
github.com/syvwlch/Printable-Clock-Project

Major improvements include: the ratcheting drum, countersunk holes for the frame, a snap-fit extendable pendulum, and an escapement design which should tick as printed (little or no hand-finishing required).

I tried to go for a four gear clock, but getting a 60:1 ratio in two gears is just not practical... the pinions get too small. I also went ahead and added hour and minute hands. I can make alternate parts for a hand-less version if the concentric shafts are too much of a problem.

Here is a parametric version of rustedrobot's ratcheting drum design for the printable clock project.

All the design cleverness is his, I just made it fit into the existing code so that it could be invoked for the drum gear.

Sorry, couldn't resist the pun. :-D

The mixer bit is done in OpenSCAD, and parametric, including the use of a function to control the position of the channel knobs.

Feel free to re-use and make cufflinks or whatever.

The cap went for a spin in netfabb's cloud service so that it would load properly in OpenSCAD. I've included it here for reference.

Also known as Clock-in-a-Cage!

WARNING! Since we still don't have a working escapement mechanism (see test jig #2 thingiverse.com/thing:8275 ), this is NOT a working clock, yet. Hopefully, it will be eventually. :-)

The Planetary Gearbox Clock is a collaboration with Emmett, who designed the original planetary gearbox and helped design and stack two of them with a 60:1 and 12:1 ratio respectively. I just slapped the escapement system on the back side and designed a cage-frame around it. The dove-tail snap-fit tabs for the cage I took from relet's excellent thingiverse.com/thing:6214 .

The intent was to do away with concentric shafts altogether, by putting the entire gear-train inside the shaft, as it were. The frame must hold the stator rings without interfering with the hands that stick out the side of the rotor rings, hence the cage design.

When I saw WilliamAAdams' metal rail wall hanging system, I immediately thought of two little mods for it:
1. A clip that could be added after installation, to add support without having to slip it on from one end of the rail.
2. A support piece that leaves the top edge of the rail free, for something to slide along it without hitting anything short of the two extremities.

It's all OpenSCAD, so it didn't take much longer to think it than to do it, so that's what I went ahead and did.

Kudos to WilliamAAdams for writing such a clean code base, by the way!

tc_fea is right, copiers are the devil's spawn. How many perfectly innocent originals have they accordioned over the years, uh?

Well, it's time we gave the Evil Copier what it deserves!

How do you like THEM staples, Mr Copier?

So far, I have been using an ideal Graham escapement with a ratchet wheel. They are simple to tune and to draw, and still in use in grandfather clocks today.

The issue is that with those sharp teeth, they are not that easy to print, and since proper function depends on the radius including tooth length... they are not the best choice for a printable clock.

The club-tooth escapement does not have this problem, and while it is harder to tune, it also offers more flexibility because the escapement and the wheel interact at multiple points, not just at the sharp end of a ratchet tooth.

Example of tuning difficulties: this escapement as drawn is not quite symmetric in its operation, and the impulse provided to the pendulum on one swing is a little larger than on the other. I need to tweak the pallet face sizes to adjust for that. :-)

It took me next to forever, but since we still haven't gotten the test jig to tick, I guess I'm not that late. :-)

Here is a clock script (intended to work with my clock builder script) for an 8 gear clock with hour, minute and second hands but with all the improvements we have currently made to the test jig... and an actual solid, connected frame that is composed of parts without any overhangs. I think this is revision D, but who's counting?