Building a new set of arms for my @Richard_Horne 3DR. Bought a set of these adjustable aluminium rods as an experiment.
Has anyone else tried these? If so, anything to look out for particularly?
My thought is that given how sensitive a Delta is to rod length, having the rods not be of fixed length would make reliable printing impossible (by their nature 3D printers are high vibration environments). An interesting test will be to see how reliably the rods hold their set length while in use.
At the minute I’ve just screwed the traxass joints straight onto the aluminium rods. One end of the rod is a left hand thread and one right hand.
On a ‘normal’ carbon rod with two right hand threads any vibration would screw one end further in and the other out but the overall length would stay the same.
With this set up any vibration that leads to rotation of the rod will change the length.
I’ve not calibrated these yet. Need to build a jig to do so. Once that is done I’ll paint a witness line across the joint and rod. Any movement should be seen if the witness lines move relative to one another. That sound reasonable?
By the way, these took a long time to get here from China but I ended up with a spare set. If anyone wants a set of six (gratis, but UK only, sorry) then I’d be happy to post them on.
The place I got them from, HobbyKing, has loads of different sizes. I picked these short ones to match my existing ones closely.
adavidm
Sounds like a great plan. It will give you a good idea of the stability of the setup.
How much does it weigh for each one? I’m curious how it compares to carbon rods, which work great but are a bit more work to get built at the right length.
Difficult for me to compare quantitatively, I dont have scales that can measure that precisely. I should get some!
All I can say is that they feel only marginally heavier than my existing setup, which uses steel threaded adapters and smaller plastic joints than these. They feel very stiff, I’ve no concerns there. The appeal to me was that they took less than 5 minutes to build and can be adjusted/calibrated very easily. I’m just hoping they dont work themselves loose over time, but a drop of thread-locking glue should solve that if they do.
Real life prevents my getting them installed at the moment, but I’ll be back on it after the weekend.
adavidm
With a little threadlocker, I’m sure you’ll have a nice and reliable setup. And I agree it’ll be rigid enough. Not bad for just a few minutes work!
That’s a nice solution. A drop of superglue may be required when they are calibrated.