Fretsaw / Hacksaw / Coping saw

thingiverse

Hi all, If you can look past the terrible print (extrusion issues), I've designed a 3D printable saw that's capable of taking coping and fretsaw blades. There are better designs available, but I didn't want to just copy existing hardware. Hopefully, this design mitigates some of the limitations in using plastic. It's fairly simple to use, but it will require some hardware, including grub and machine screws, which I'll list below. I've split the saw into four main parts: * The body is self-explanatory and should be printed with at least 3 top/bottom/perimeter & 50% infill for rigidity. You want it sturdy, and I can assure you that those settings (PLA is fine, but PETG would be better) will make a big difference. * The handle is threaded 10mm and uses a piece of 40mm threaded steel rod. This makes it very strong, and I've included a printable threaded piece as well. You can design your own handles and just screw them on. * The clamping blocks are printed separately for two reasons: they will wear out with use, and printing them individually takes an hour, while the body takes 9 hours to print one. This way, you can print a load of blades ready to go, making changeovers much quicker. They only fit in the body one way, so you don't have to worry about orientation. * The tension block (orange) has two M3x20mm machine screws running through it, which are used to post-tension the blade and push against two M3x3mm grub screws set into the saw body. Each block has an M5x8mm grub screw on each side to grip the blades. There's also a set of inserts with a smaller opening to make loading and using fine fretsaw/jewellers saw blades easier. I've only got cone-bottomed type grub screws, but you must grind the bottom flat to use finer fretsaw/jewellers saw blades or they'll snap when you tighten them. To load a blade for the first time: * Adjust the grub screws in the blocks until they're approx centred in the slots. * Back one of the grub screws off a bit in each block (try to remember which one). * Insert and tighten a blade into the smaller (green) block, making sure it doesn't stick out the other side. * Feed the blade into the larger (orange) block but don't tighten yet. * Place the green block into the saw and slide the orange into its slot. * Squeeze the body of the saw, which will push the blade further out the back of the orange block and put tension on it once tightened in place.