Making a 360 degree hinge

Here is how I made a 360° hinge for my fishing, and metal pellet casting molds. I have been working on these for quite a while, and have went through many different versions. They are entirely cnc machined from billet aluminum. This is how I made the latest one. Now to mass produce these! Do you want one? Click here to pre-order one.
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I could not find any hinges that had no slop in them. The two mold halves have to line up and stay closed. If there is slop in the hinge then you don’t get a seal and it leaks. Also, it needs to be heavy duty, those handles are long and put a lot of leverage on the hinge. And not just that, but because we are casting metal, it needs to be fireproof.

Design the connector links in CAD, and then program the CAM paths.


Find a piece of steel, line it up, and clamp it down on the CNC.


Drill a buncha holes at exact spacing.

IMG_0747 IMG_0751

Then use a tiny end mill to carve them out.



Now we move on to what really makes this thing work, the gears.


Without the gears to restrict the motion, you end up with a hinge that does this:


Temporary slotted axle mounted, so I can line them up.


Positioned and clamped in the vise, ready for a haircut.

IMG_0742A little off the top and you end up with this. Now to assemble it all!


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