Pipe bender marking pipe

[!lsx!]

Hi

I'm trying to learn the basics of how to use my new Hilmor GLM pipe bender. I'm not a plumber, just someone who'd like to learn how to do my own bends rather than using elbows.

So I've done some test bends on some old bits of pipe, but I'm getting pitting (bits of silvery colour not copper) along the side of the pipe from where the pipe sits in the former (see pics).

I'm getting the marks when I use the 15mm and the 22mm which makes me think I don't know what I'm doing rather than a defect with the bender. There is a rough patch in the casting on the 22mm former (see pic), but it's in the centre so I imagine it's not the problem.

Any advice appreciated. Please help

Thanks

 

[johnny2007]

It's normal, won't affect integrity of the pipe.
After all you're stretching a tube made of copper...

 

[Gasguru]

Wait till you bend 22 and the inside radius is rippled

 

[!lsx!]

Wait till you bend 22 and the inside radius is rippled

So I have nothing to worry about then?

It's just none of the videos on youtube show the pipe being marked like I've got.

 

[Gasguru]

The casting looks poor but it's almost certainly a Chinese made bender.
You could try a little grease but I wouldn't worry about it.
You could always try British made.. https://www.benditnow.co.uk/product/bhb-15-22-15-22mm-hand-bender/