How hard are copper heatpipes?

May I ask if anyone knows how hard copper heatpipes are and if it is possible to bend them by hand/without heat? I am slightly confused as I have come across sites that said heat is needed but also sites that said the pipes are really malleable and soft? Anyone has any idea? Thanks!

 

You can bend them but it's important to know that they will just kink and you lose significant efficiency.

 

If heat is uses correctly would it still kink?

 

Thanks, will check it out!

 

To avoid kinks:
E.G.
Pipe bender 3 In 1 180 degree 6mm / 8mm / 10mm Pipe Tube Bender / Copper Tube / Air Conditioning Tube Manual Elbow Tool @12
https://s.click.aliexpress.com/e/b3Z6V1Ji

Heat pipes have really thin walls, the smaller the diameter, the thinner the walls. Usually about 0.5mm or so, they are very fragile. It is far better to bend, then flatten. Once flattened they are harder to bend along the plane of the flattening, and too tight a bend risks a tear on the long side, and any bend perpendicular has a high risk of collapse or kink.

Any crack or fissure will cause the vacuum to be lost at which point its thermal conductivity reverts to that of a plain copper tube. Kinks are almost impossible to remove. Collapses however can usually be remedied by heating up the heat pipe just enough so that it swells up, but then it will have to be re-shaped and re-flattened.