Designing A 3D Printable Clamp
Clamps are devices used when you need an extra pair of hands and cannot seem to find them anywhere.
What you will need:
– A CAD package
– Some Creativity
– Access to a 3D printer
If you are just looking for the Clamp STL files you can download them now. For a more detailed and educational experience, just follow the simple instructions below:
- Setting the basic shape.The corners and the mid-section of the span are the points that will be experience the most stress when tightening the clamp so in my design these were made a little wider (If you are interested in learning more about how this works you should look up; second moments of inertia). The clamp was designed to be symmetrical as this would make it more practical and would increase its general aesthetic value.
- In this case the C shape was extruded to a height of 20mm
- A hole was added to one side and a screw thread carved using a helical sweep. The threads on the screw were a little too sharp to 3D print so a small 0.2mm round was added to help them along. Also, a chamfer (0.35mm which is the maximum without causing an error in the mesh in this current software) was added to the side where the screw would be inserted to make it easier to match the threads.
- 3D printer software usually has a few settings that allow you to control the outer wall thickness and the inner fill. From a structural point of view, most of the strength and rigidity will be a result of the outer shell. With this in mind we can introduce small features that can help us get a better functioning clamp.
- Small toothed ribs were added to the bottom to help clamp have better grip things.
- Finally, adding rounds to internal and external corners help reduce stress concentrations and make the part look a little sleeker.
- A small hole was added to the clamp side to make it easier hang these clamps for storage.
Started off by extruding a shaft of 88mm and 10.7mm diameter. The ~0.3mm clearance between the screw and “nut” should be enough for 3D printing however this depends on the accuracy of your printer. A screw thread was created using an additive helical sweep around the shaft.
Access helix was trimmed off to achieve a more natural curve. This was done using a simple Boolean operation. Chamfers were added to the other tip to make it easier to insert into the C-Clamp
The ball is revolved over the top end and around the shaft center.
A square section knob was included on the other end. The square shape should make it easier for the user to twist when compared to the other circular knobs. Chamfers and rounds were added to match the styling of the knob to that of the body. And also to accommodate twisting of the knob when in close proximity to the body.
Checking Screw match; it is always a good idea to check if the screws match up. You can always modify the design later if they don’t work exactly as required but taking a few extra minutes to section the part will give you a good indication of where potential stumbling blocks may be.
The last piece to include is the swivel head that clamps down over the work piece. The swivel helps clamping as it allows for the face to always fit flush against its mating surface, even if faces of the work piece are not exactly flush.
The mating face was created and a hollow ball was added that will act as the swivel joint. This was done using yet another revolve while making sure the inner diameter is quite a bit larger than the ball tip in the screw.
Rounds were added and a couple of slots 1.5mm thick added to the model. These slots are designed to allow the walls to flex enough to clip over the screw`s ball. A few more rounds are applied to make the swivel plate conform to the general design.