Tube Cutting Jig

thingiverse

I needed a way to cut thin-walled brass tubing quickly and efficiently, but my hobby miter box just wasn't cutting it - literally. Jewelry supply stores sell hand-held cutting jigs that can handle up to 1/4" diameter tubing, but they're often pricey, and more expensive models will only cut up to 1/2". This jig has the added benefit of holding a long piece of tubing rigidly while you cut it, allowing for perpendicular-enough cuts for most purposes. To get absolutely perfect cuts, though, you might need to use a dedicated miniature chop saw. **Supplies Needed:** * A length of angle iron - 1-1/2" x 1-1/2", 1/8" thick * Metal file (to true up the end of the angle iron) * C-clamps **Instructions:** Print a TEST V-block, 10mm in the Z, to ensure the V-blocks fit snugly. Adjust your printer's settings until they fit correctly. Print at least two V-blocks and one V-block for the C-clamp. For every extra v-block you print, also print an extra V-block for the C-clamp. The C-clamp will press down on the Circle Block (design your own for what you're clamping), which presses down on the tube. While your parts are printing, find a perpendicular reference and file down one end of the angle iron until it's to your liking. Once printed, slide the V-block onto one end, then another V-block, alternating them. The C-clamp will use the V-block or V-block for the C-clamp to press against on the bottom. **Instructions for Use:** Mark your tube and take into account the kerf of the blade. Using two c-clamps, carefully fix the tube in place with a Circle Block spreading the load on the metal tube. A V-block should be below the clamp. Using a metal saw - I prefer a jewelers saw - carefully press the blade up against the angle iron and cut. Provided the blade is angled correctly, it should waver very little. Also, when choosing a saw, opt for one with minimal set (ie, flush cut) since this will be rubbing up against the metal guide. **Future Improvements:** * Screw holes in the V-block to affix to a wooden board * Semi-permanent clamp fixation - right now the clamp is loose * Flexible top block for clamping to various tube diameters (ie, thicker design for TPU) * Slightly more "generic" V-block design or openSCAD variant. This was measured to fit the angle iron from my local hardware store, and may not work with the angle iron you find in your store. I'd be happy to code up an openSCAD variant for customization.