Twists in pipe offsets?

[Ben ten ten]

How do you prevent twists when you offset copper pipe? I must be doing something wrong, but I can't figure out exactly what. The offsets are perfect apart from the slight twist I have to flatten out afterwords. Any help, or ideas please?

 

[Madrab]

When you're pulling the 2 bend you don't have the 1st one totally in line to the direction of the 2nd pull, look down the length of the benders to the 1st end to get it in line with the direction of the pull/in line with the guide.
If you think it looks straight and then when it's pulled it's a bit out, you just need to adjust the position of the pipe slightly further over than you think, from the direction of the usual twist, so the next time it pulls straight. You'll eventually get to know where to look down the benders to get it right.

 

[Razor900]

Most plumbers just eye it through on the benders to make sure it's in line or you can put a straight edge against the side of the former aligned with the end of the tube. Make sure the gap between them at the far end is the same as it is at the benders and you'll be spot on

 

[dilalio]

Like @Madrab said, if it's twisting by the same amount each time you pull one, then you just have to overcompensate left or right when eyeing up on your benders... Think of it like looking down the barrel of a shotgun - everyone is different and has to train their eye accordingly!