Printed Push Rods? That's Crazy!

I've decided to try out 3D printed push rods.  Am I crazy? Probably.

For the record, this is not the super secret idea that I've got up my sleeve, as I have previously mentioned.  I will save that one for later.  Having the magnetic joints will make it super easy for me to swap out different push rods whenever I feel like it.

Some of the newer filaments, like PLA+, carbon fiber filled PLA, and PETG, are really strong, lightweight, and durable.  I thought about the carbon fiber tubes that most people are using, and while they are very strong and lightweight for their size, they are generally very small in diameter.  We all learned in school that a tube of a larger diameter is much stronger regardless of the material.  This is why race cars are built from steel tubes rather than solid steel bars for example.  If I could obtain a carbon fiber tube 20 mm in diameter, I am sure it would be really strong, but it would also cost a lot of $$$.  However, if I can print a 20mm tube, it will still be incredibly strong, and cost a lot less.

I whipped up a design in OpenSCAD, but it's much larger than anything I can print on my printer, so I will have to have a friend print them.  I'm thinking they would look good in some clear PETG.

The design is basically a 1 mm thin 20 mm diameter tube that tapers on the ends down to about 6 mm.  The ends are solid with a 4mm hole through them for a screw.  There is an access hold to put the screw in and tighten it.

On the outside, the screws stick out the ends just enough to screw on one of the threaded steel balls. I'll be able to fine tune the length of the rods by adjusting the tightness of the screws.

I've printed and tested a few of the ends using PLA+, and they are incredibly strong and rigid.  In fact I would be willing to bet money that these are stronger and more rigid than most of the rods in use today, regardless of what they are made from.

No comments:

Powered by Blogger.