I needed something to slow the re-pressurization of a vacuum chamber at work when disconnected—and immediately thought of a roller clamp—so I designed this.

It's a roller clamp for 3/8outer diameter, 1/4 inner diameter flexible PVC tubing (e.g. a 20' roll from Home Depot is less than $5). I have included 2 rollers, a larger one and a smaller one. The large one is sufficient to completely stop flow through the tubing, and the small one allows for a small degree of leak when fully 'clamped.' While I have not calibrated the flow rate through the clamp at various positions, I can say that it offers a good degree of adjustability. The flow rate of a liquid or gas through a piece of tubing with this clamp attached can be controlled by rolling the dial up or down. The degree to which the dial squeezes the tubing corresponds to a change in cross-sectional area of that segment of tubing, affecting the rate at which fluid can flow through it at a constant pressure. This clamp is very similar to one you might see attached to an IV in a hospital; a mental image of this sort of roller clamp was used to design it. I use this clamp in the lab to slowly release a vacuum from a container attached to a piece of tubing.

The main body of the clamp does not require support when printing, assuming that you print it vertically, such that the largest end of the clamp (the top) is on the bed, and that your printer can handle the small amount of bridging required the bottom of the clamp body (top of the first picture). The rollers should also be printed with support, and on their side (i.e. on the face of one of its 'axles'). Aside from removing the support, no other alterations should be needed. After printing, slide the roller into the body of the clamp, and pass the tubing through the body. The roller should now be locked into the body, but should not squeeze the tubing at its 'loosest' setting.

Designed using OpenSCAD in October 2013. Refer to its Thingiverse page for downloads and more information.

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This adapter allows you to securely attach almost any phone to almost any microscope for capturing still images or video, or for use as a digital display.

After several iterations and bit of testing, I came upon this design. The deep eyepiece clamps allow for focus adjustment, as the optimal distance from a phone camera to a microscope eyepiece can vary. The broken eyepiece clamp allows for adjustment to fit a wide range of eyepiece diameters. The sliding phone supports allow the adapter to fit a broad range of phones (pictured is a Nexus 4, though larger or smaller phones also fit), though the design may need to be enlarged in the future if screen sizes continue to grow.

I designed the adapter myself, tested it with coworkers and friends, and borrowed the 'knobby knob' from Thingiverse Thing #26752.

Parts

Before assembling the adapter, you'll need:

Copies of each 3D-printed part

Qty.	Part
1	Adapter body. The non-flipped version will fit the vast majority of phones, but a flipped version is provided just in case. If you are unsure, look at the back of your phone; if your camera is on the left, then use the non-flipped version (e.g. for all Nexus phones, Galaxy-series phones, iPhones, and most others), otherwise, use the flipped version. A file exported directly from OpenSCAD (from the rev4a SCAD file) will have some non-manifold edges, so a corrected STL is also provided (rev4b).
1	Outer half of clamp
1	Inner half of clamp
3	Sliding support
5	Knobs, of either variety. I printed three of the round knobs, and two of the knobby knobs. Keep in mind that the knobby knobs are much easier to tighten; for the clamp I'd recommend these over the round ones.

Hardware

Qty.	Part
3	#6-32 machine screws, 1.25" length
2	#6-32 machine screws, 4" length
10	#6-32 nuts

My local Home Depot doesn't sell #6-32 screws longer than 2.5individually, but I did find the 4 ones as part of a set of toggle bolts that I bought for less than 1 USD.

Assembly

Attach the body to the inner clamp using epoxy, CA glue, or an acetone/ABS slurry if ABS was used for the print. If your print bed is large enough, you might prefer to print these as a single object.

Attach each knob to the corresponding screw by sliding the screw through the hole (the hole might need to be drilled out slightly, depending on the calibration of your printer), and threading the nut onto the other end. Using a pair of pliers (on the nut) and a screwdriver, tighten the screw head into the indentation in the knob.

Drill out the holes in the eyepiece clamps and sliding supports slightly so that the screws can move freely within them. I think I used a 1/8" drill bit for this.

Placing each remaining nut into the corresponding nut trap, assemble the remaining parts as shown in the pictures.

If desired, add Sugru (moldable silicone) to the insides of the eyepiece clamps and sliding supports for better grip.

Finally, take some beautiful pictures!

Tip: if the edges of your images are fuzzy, try loosening the adapter and moving it up and down until they come into focus. Tighten.

Designed using OpenSCAD in April 2013. Refer to its Thingiverse page for downloads and more information.

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This 5-part 3D-printable design uses a 120 mm PC case fan and cheap activated charcoal filter pads, and may be used for solder fume extraction or airborne particulate extraction (e.g. for 3D printing with ABS).

The base features a cutout for mounting a power toggle switch (1/2x 3/4 rectangular cutout), a cutout for a rectangular 12 V DC power jack (9 x 11 mm), and an enclosed area for hiding cables.

The left leg of the device includes a recess for hiding the fan power cable, along with retention clips to retain it in place.

Both legs include nut-traps (slots for securely holding nuts) for the 1/2" 10-24 screws required for attaching the base of the device, and the rest can be assembled with long 10-24 screws or with zip ties (pictured).

A relatively powerful fan is needed to pull air through the 4 activated charcoal filters that I used, though fewer filters can be used if necessary. The fan may be mounted to the back of the device or the front of the device; here I mounted it to the front, as there it proved to be more effective.

Designed using OpenSCAD in 8/13. See Thingiverse page for downloads and more information.

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