Hi, I am wondering if it is possible to use builders expanding foam to strengthen/prevent crushing (to a certain extent) on your Ø12mm Carbon pultruded tubing?
I made an automated camera dolly/slider for shooting timelapse videos etc and although the tube is strong enough to support the weigth of the camera,lens etc I tend to have to treat it with care when out and about. Firstly,Would filling the tube with expanding foam fulfil this purpose? and secondly, Would the foam split, bulge or otherwise distort the tube? Any help would be greatly appreciated. TIA Hadrian

You could slide another smaller dia tube inside the first giving twice the wall thickness.

I looked at the tubes and they were a near perfect fit together.

IF the tube ends are open, then there should be no issues with splitting or distortion as the foam has somewhere to go and thus shouldn't build up any pressure. 

It would help stop the tube crushing and absorb a little energy but the carbon will still likely get damaged. A thicker wall would be a better choice.  Our Roll Wrapped tubes are stronger in crush strength if you can accommodate the sizes.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Thanks for both replies, Unfortunately I have glued in turned alloy inserts in each end so inserting smaller diameter tubing is out of the question but if I do suffer a breakage I will definitely keep the idea in mind, I had though of using balsa dowels but was unable to find any with the correct diameter.

Warren, thanks for the reply, fortunately the alloy inserts are drilled and threaded thro' so I will attempt the expanding foam. If all else fails I will probably opt for the Ø12mm/Ø10mm woven.

Thanks once again Hadrian