Alternative to carbon fiber arms?

Hi,

im upgrading some frame parts of my 40x40x50 delta and while looking at how the frame behaves I found out that the weakest link are the carbon fiber arms. Its not really bad and the machine works but they are also 40cm long so in the middle the wiggle quite a bit. I was thinking about aluminum tubes or square tubes and wondered if the added stiffness justifies the added weight.

Anyone using non carbon fiber and wants to share some opinions?

Carbon fibre will be stiffer per unit weight than just about anything else out there. Look at bigger diameter tube, and use woven rather than pulltruded rod.

I'm using steel rods on one of my deltas, but carbon fibre tube would be stiffer and lighter.

Just add some strengthening structure to the center of the rod. Like a short bigger rod glued in place.

yup, the best and only alternative to carbon fibre arms is better carbon fibre arms

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RepRapPro Mendel 3 Tricolour
RepRapPro Fisher
-Carbon Arms
-Easy adjust Carriage+effector
-axis stiffness mods
HE3D -600 delta
-Duet 0.8.5
-PanelDue
-DC42 Height probe
-RobotDigg metal components
Simplyfy3D
RS Design Spark CAD

Quote
nebbian
Look at bigger diameter tube, and use woven rather than pulltruded rod.

Stiffest tube in bending is unidirectional, not woven. [www.rockwestcomposites.com] . I use some of their 10mm od uni carb tube, very stiff.

I didnt know that and I have indeed only pultruded rods. Ill looks into getting something stronger. Thanks for all your inputs.

Pultruded is by nature unidirectional. While you get some benefit from compression during the wrapping and heating phase of unidirectional rolled tubing as opposed to pulltruded, a greater benefit can be had with larger diameter tubing.