Hi, this is Wayne again with a topic “3d Printed Hand Knobs”.
Not every bolt in your next maker project needs to be torqued down to spec and for convenience hand, knobs can’t be beat, but they’re not always easy to source in just the size. You need, if your hardware store, carries them at all in this project. We’Ll learn how to design a hand knob that you can 3d print and then glue over any bolt that you already have other than your computer and 3d printer. The most valuable tool in this project is a digital caliper. This allows you to take precise measurements of the parts you’ll be working with for this project, we’ll be using the warhorse of photographic attachments, the imperial quarter 20 bolt. There are three measurements on this bolt that concern us. The diameter of the bolt head, the depth of the bolt head and the diameter of the bolt shaft, including the threads.
The metric system, is far more common of a measurement in 3d printing design, so we’ll be measuring in millimeters. When measuring the diameter of the bolt head, make sure that your measurement is from the points of the hex head, not the flat sides, note down all three measurements, we’ll be using autodesk 123d design to create our hand. Knob start by creating a few basic 2d shapes that describe our model.
The first will be the outline of the bolt head, create a polygon place its center, wherever you like, and then change its radius to half of the measurement you took down and the sides to then six a circle for the outer body of the hand knob place. The center of the circle in the same point as the hexagon and set the radius to 15 millimeters, now we’ll place four smaller circles. At the four points of the main circle, which we’ll use to cut out grip points for the body of the hand, knob circles with a seven millimeter radius should fit nicely it’s time to start building our shapes into a 3d model, select the main circle and extrude. It a few millimeters more than the depth of your bolt head. Six millimeter should do well, then select the hexagon and extrude it to our measurement four millimeters by default. If you extrude one object into the space of another one, two 3d design will subtract the volume of the new shape from the original, which is what we want to do here. Next extrude, each of the smaller circles by six millimeter to form the grips of the hand knob. We don’t need any of our original 2d shapes anymore, so take a moment to delete them and clean up our workspace. Now we’ll start to build up a collar for the bolt for a little more structural strength, create a seven millimeter circle and place it on top of our hand, knob extrude the shape by four millimeters, but before you confirm notice that the extrusion is pushing down into Our knob, rather than out above it change your extrusion value to negative four millimeters and then confirm. The last thing we need to do is to create a hole for the shaft of the bolt to pass through, create a circle on top of the structure with a radius of 3.5 millimeters, then extrude it down through the entire model. 12 millimeters.
Our shape has all the structures modeled for it to function properly, but it doesn’t look very nice to hold first, let’s finish off the edge of the collar with a chamfer of 0.75 millimeter. Then, let’s round off the corners of the hand, grips use the fillet tool and select all eight of these vertical edges, set the radius to three millimeters and confirm the fillet. Our model is now ready to print export it to an stl and open it in your printer’s slicing software. The model should print fine without any support structures, but you’ll want to use a good deal of infill to give our hand knobs some strength.
At least 70 percent – fortunately, it’s a small model, so it shouldn’t affect print times too much check the fit onto your bolt. You might need to adjust your tolerances depending on the printer and filament. Every one is a little different if your fit is good glue.
It onto your bolt using epoxy or cyanoacrylite your hand, knob, is now ready to use this. Build is adaptable to just about any bolt size and the knob can be redesigned to any way that suits your project, be sure to hit subscribe for more make projects, and thanks for watching you .