Push rod help 😩

[Coopers87]

Right spitfire build is under way, and everything is built, servos are placed in there marked position with diy control horns in place, but the problem I am finding is I am getting a lot of flex in both tail push rods so limiting my throw of both surfaces due to them bowing in centre
Any ideas on how to solve this problem, using 1mm wire for my push rod material.
Lee

 

[Chuppster]

One way you can help the deflection is the sleeve the pushrod in a coffee stirrer. Alternatively, for especially long control rods, you can guide them with zip ties tightened down all the way. Just cut the tail to a point and stick it/glue it into the foam board.

 

[Hai-Lee]

As already stated a coffee stirrer would suffice but in reality any semi-rigid small diameter tube would suffice.

One I use occasionally when I do not have the correct grade of wire to make a rigid enough pushrod is to use a few lengths of heatshrink to fix a BBQ skewer to the centre section of the pushrod, (securing each end and the centre). Whilst it adds a little weight it often weighs less than the correct gauge pushrod.

Personally I tend to mount all servos within a single straightened paperclip length of the control horn. The paperclips are easy to bend with pliers and rigid enough to take the servo generated forces. A few times, (due to a spectacular lawn darting episode) I have found that the servos survived as the paperclip bent and saved the gears in the servo.

Just some thoughts!

have fun!