This is an attempt to make a secondary mirror mount for a trackball telescope, specifically Jerry Oltion's design. The original Oltion design used a vitamin bottle cut at a 45-degree angle.

It prints in two parts, which should be snapped together to make a ball-and-socket joint. Then thread two 3"-long 8-32 screws through the long holes to contact the bottom of the mirror mount surface, and connect one small spring to provide restoring tension between the mirror mount surface and the main block. Advancing or retracting the screws allows the tilt of the mirror mount surface to be adjusted in two directions to properly align with the eyepiece.

The main block includes two curved holes set at right angles, allowing two wires to be threaded through. These are for attaching to the interior of the secondary cage, forming the "spider" mount.

This is a work-in-progress, and I will add photos of the part fully installed in a trackball telescope once they're available.

My new acoustic guitar is unhappy in the dry winter air, and the strings buzz badly. So I made this humidifier, which holds a damp sponge. By putting it in the case with the guitar, the guitar wood is re-humidified and the strings sound great again! (Now I just have to learn to play it...)

Note that this is sized for the sponges I happened to have. You may want to scale it as necessary for your sponge.

For more on guitar humidifiers, this site has some good information.

Having lots of guests over for turkey this year? Stop giving them new wine glasses every time they turn around - instead, give them wine charms to keep track of which glass is theirs!

Intended to hold a shelf in kitchen cabinets. Needs to be printed with supports. Was very strong once I got the peg diameter right for my cabinets - yours may be different!

Two of these will be most of what you need for a toilet paper holder - just get the central spring-loaded roller and you're good to go.

This is designed to attach to a 1/2-inch optical post and hold a 1-inch cylindrical object (like a flashlight) at a right angle. The set-screw holes are sized to be tappable to 8-32. Prints nicely in this orientation on my Printrbot Simple.

This is designed to accommodate a 1/2-inch optical post. The hole is sized to be tapped for an 8-32 screw.

[Updated to give slightly wider internal radius for smoother post insertion.]

This is designed to hold a 25x75mm microscope slide for optics experiments. The bottom hole is sized to be tapped for an 8-32 screw, allowing mounting on a 1/2-inch optical post.

My Printrbot Simple occasionally has a problem with the extruder overheating during long prints. Other people also report having this problem, and have mounted fans to keep the extruder cool. This is my design for a 40mm fan mount, which works quite well.

I followed the suggestion by Nathaniel Chapman to power the fan from the heated bed port (which is unused); this requires putting a 100K jumper on the T-BED connection to simulate a thermistor, and adding some gcode to the slicer (M140 S60 to turn on the fan, M140 S0 to turn it off).

I used Elfa drawer file channels to make hanging drawers for my standing desk. For the runners, I used the file channels, and attached them using this small bracket. It's reasonably strong, and the screw head doesn't get in the way of the drawer.

Note that there are two screws: one is for the outside tab and is straightforward, but the other one needs to be inserted within the channel to reach the inner hole. I found that a 1/2" screw just barely fit.

This futuristic version of a popular springtime marshmallow treat was developed for an entry in the 2014 Washington Post Peeps Contest (http://www.washingtonpost.com/lifestyle/magazine/peeps/). Unfortunately the entry ("A Peep Into the Future") didn't impress the judges, but hopefully this design will be more popular!

Made for a "summer in Spain"-themed party. Enjoy!

The ancient Greeks enjoyed a game called the Stomachion, which consisted of a square tile cut into 14 different polygons. Assembling the polygons into other shapes, or reassembling them into the original square, was (and still is!) very challenging. Archimedes played this game, and may have stumbled upon the basics of modern combinatorics while doing so (see the Archimedes Palimpsest for more information).

This is a small 3d-printed version of the game, scaled for my Printrbot Simple. Enjoy!

Hourglass one by Colin and Junia [created on 3DTin]. Can somebody please put some monkeys into the little cages???

A series of linked open cubes, held together (I think) by solid spheres. [Created on 3DTin]

Be careful trying this at home! [Created on 3DTin]

Improved circle mesh box ornament [created on 3DTin]

Triangles by Colin and Junia [created on 3DTin]

Open ball by Colin and Junia [created on 3DTin]

Circle mesh ornament box by Colin [created on 3DTin]

Wreath by Colin and Junia [created on 3DTin]

Ornament by Colin and Junia [created on 3DTin]