Cox R/C Cub - Fix Warped Styrene Foam Horizontal Stab

davehour Wed Aug 17, 2022 7:15 am

Hi,

I’ll appreciate help to straighten a warped styrene foam horizontal stabilizer of a 1979 Cox Radio Control Cub Trainer. Please see pictures.

Thanks!

Cox R/C Cub - Fix Warped Styrene Foam Horizontal Stab C0da9310

Cox R/C Cub - Fix Warped Styrene Foam Horizontal Stab 939de110

Marleysky Wed Aug 17, 2022 8:40 am

HOT WATER ! Not Boiling, but really hot. Gently pour water over bent or warped area and rub vigorously to reshape to desired shape. Let me see if I can find the video where I saw this being done.

edit: here are a few to view. there is one where the surface is "re-covered" in film to add some stability.
https://www.youtube.com/results?search_query=repairing+foam+airplanes+with+hot+water

OK ! SO I'm full of HOT AIR. That too will fix bends on your wings and tails

looks to easy...https://www.youtube.com/watch?v=ZvLZjWpKOlA

davehour Wed Aug 17, 2022 10:16 am

Thank you so much!
I’ll give it a try and let you know how it went.

davehour Thu Aug 18, 2022 9:04 am

Hi,

I tried the blower method and didn’t work.

I’ll place the horizontal stab pass straightened on hot ambient temp for several days.

Levent Suberk Thu Aug 18, 2022 9:18 am

Hi, open a groove along wingspan underside, then epoxy carbon fiber rod into this groove. If you don't want to do this then cover wing with brown paper with PVA glue and set the wing to dry under weights.

davehour Fri Aug 19, 2022 1:04 pm

Hi guys,

I was able to straighten the horizontal stab.

I used a large pan and hot water. The pan was filled to the top to be able to heat the warped area only. Water temp was about 150-170°F (estimated). After heating the concave side of the warp, the horizontal stab was pass straightened.

I recommend you start heating just for a few seconds and see what it does. Change heating duration accordingly.

Thanks.