The Ultimate Darkroom Printing Test Strip Maker

Before you read any further, you should know that this model has been supplanted by Test Strip Omega.

It's unnecessary! It's over-engineered! It's...

1. Effective. Consistently prints the exact same piece of image area onto each of 4 test strip sections, so you can make 1:1 comparisons between different exposures.
2. Efficient. Each test strip is 2.5 x 4", or 1/8 of a standard 8x10 sheet.
3. Flexible. Height adjusts to match focus with virtually any easel.
4. Fiber Friendly. The carriage and optional drying rack defy stubbornly curling paper and keep things nice and flat.
5. Fun. Magnets align each section of the test strip as you advance it. Clinically proven to be weirdly satisfying.
6. 3D Printer Optimized. You'll find no supports, tough overhangs/bridges, or non-chamfered edges here.

Bill of Materials

• (1x) Of each .stl file
• (8x) #6 x 3/8" screws (if you have anything similar, try those first)
• (10x) 6x3mm neodymium magnets
• (4x) M5x20 bolts - I used M5x25 hex heads that I had on hand, and found them unnecessarily long, but they work fine
• (4x) M5 hex nuts
• A little superglue. I like this gel stuff
• Some sticky poster tack for the feet helps the housing stay put while you're advancing the test strip

Video Instructions

I highly recommend black Jarees Matte Black PETG - it's more matte and less reflective than any other black filament I can find, as well as being highly opaque with few layers. It's also particularly easy PETG to print well, in my experience. A perfect material for any kind of darkroom tool. That said, probably any non-translucent black PLA or PETG will work fine. The parts are fairly thick. Up the infill % and use cubic or octet pattern if you're worried about it. YMMV.