Simplifit Curtain Rod Mounting Kit

Removing the lace curtains in the kitchen, to wash them, the curtain rod was dropped, and the Simplifit fittings on the ends flew into the air, and fell to earth I know not where. No doubt we shall discover them in a pot plant or the coffee beans or the toaster within the next week or decade, but in the meantime, this was the perfect opportunity to build a better mousetrap. The main drawbacks of the commercial versions that used to be used are: 

• They are one-size-fits-none-very-well, being made to be used with 16mm, 19mm, and 25mm rods (and probably anything in between, if such things exist). This means they sit quite loosely on/in the ends of the 16mm rods we use, which means they get lost when one is not careful, as we are, and it did.

• They cost more than they should. But then, to be fair, most things do (except matches and Toyota Hiluxes, which are far too cheap).

• They are ugly, and more bulky than required or desired (curiously again like Toyota Hiluxes). It should be unobtrusive (ibid.)

• I cannot get it right now, if right now is when the hardware shop is closed, as it was yet again last night. We require instant gratification, if not sooner. 

Find herewith therefore a parametric FreeCad version, with .step files for 16mm, 19mm, and 25mm rods, as well as the design source file, should you want to mess around with it. One can also for example simply scale the 16mm or 19mm versions in X and Y (equally) in the slicer, to achieve the desired fit on any reasonable rod diameter, up to and exceeding 25mm. 

Printed in PETG, with many (4) perimeters and 30% gyroid infill, to ensure strength. I would be wary of PLA if it gets much sun, as windowsills often do; it may get all warm and warpy (or maybe not, but I was not interested in finding out.) The end pads are printed in TPU, stuck into the recesses on the Bolt and End pieces with some double-sided carpet tape or superglue.

Correctly scaled the End cap and Nut pieces should fit snugly on the ends of the rod, making it far easier to singlehandedly install everything in the window frame. (OK, doublehandedly, but still singlepersonly.) Being more compact than the commercial versions, one could also use longer rods (requiring less extension of the fitting), but in our case we were stuck with what rods we had. This design requires a minimum of a mere 1 cm of clearance.

Remember to print two pads, in TPU/FLEX, to go into the ends of the Bolt and End cap pieces. 

Screw the Bolt into the Nut, making sure the thread turns easily. If not, you can use some XY-compensation in the slicer, or, if you feel really strongly about it, go modify the thread parameters in the CAD file. Similarly, if you need more extension range, you can scale the Nut and Bolt pieces in Z, leaving X and Y as is. As long as you keep the pieces together as a set, the threads will still match, and all should be well. But it would probably be better to rather change Thread Length in the CAD file, and best of all would be to get a longer rod, obviating the need for excessive extension.