I was always taught for bending 90’s, take off half pipe diameter for copper ( in this case 7.5mm ) and add on whole pipe diameter for iron pipe ( in this case if it were iron pipe you’d add 15mm on ). In practice, the very first bend you did in this video, you’d measure the 125mm then take off 7.5mm which is 117.5mm. Now, where you had your scrap pipe and the set square, now you wouldn’t need the scrap pipe, you’d put the set square on the pipework and slide it into the inside of the pipe former, and align the 117.5 mark to the set square. Now you don’t need the scrap pipe AND the set square, just the set square. I mention this technique because I never have access to a vice on site. I’m always scrabbling around on the floor with my pipe, bending machine and set square, so one less thing to hold is a major plus, you need 3 hands to use a bender, so by eliminating the scrap piece of copper it helps a lot. This is a very helpful video for both new and experienced plumbers, thanks for uploading. I’m a pipefitter/welder by trade, been bending pipe for nearly 40 years and can bend pipe millimetre perfect. Everyone has their own preferred technique, there’s lots of different methods to get the same 100% accuracy, learn this one and then develop your own to suit you. EDIT I never actually measure 7.5mm, come on, either taking off 7mm or 8mm will give you a very accurate bend. Just remember, bending 22mm pipe you’d take off 11mm, and bending 28mm pipe you’d take off 14mm.
I would use a hybrid of both, the problem with the second one is you are doubling the tolerances for each measurement. I would take the off set off the centre line distance and then measure once (effectively using the McKeowen method but without two lots of inaccuracies from the measuring. Hope this makes sense?
i remember Mckewons way like speed limits of car 70 mph legal for 15 mm. half 70 for 45degree third and 2 thirds of that tor 30 and 60 degrees 100 mph my speed illegal 22mm and repeat
Is there a way to do really small offsets, where a rad just doesn't line up with pre-existing pipes? It looks like the 60mm offset you did was about the limit, otherwise the bending tool doesn't have space to hold pipe between 1st and 2nd bends.
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I was always taught for bending 90’s, take off half pipe diameter for copper ( in this case 7.5mm ) and add on whole pipe diameter for iron pipe ( in this case if it were iron pipe you’d add 15mm on ). In practice, the very first bend you did in this video, you’d measure the 125mm then take off 7.5mm which is 117.5mm. Now, where you had your scrap pipe and the set square, now you wouldn’t need the scrap pipe, you’d put the set square on the pipework and slide it into the inside of the pipe former, and align the 117.5 mark to the set square. Now you don’t need the scrap pipe AND the set square, just the set square.
I mention this technique because I never have access to a vice on site. I’m always scrabbling around on the floor with my pipe, bending machine and set square, so one less thing to hold is a major plus, you need 3 hands to use a bender, so by eliminating the scrap piece of copper it helps a lot.
This is a very helpful video for both new and experienced plumbers, thanks for uploading. I’m a pipefitter/welder by trade, been bending pipe for nearly 40 years and can bend pipe millimetre perfect. Everyone has their own preferred technique, there’s lots of different methods to get the same 100% accuracy, learn this one and then develop your own to suit you.
EDIT
I never actually measure 7.5mm, come on, either taking off 7mm or 8mm will give you a very accurate bend. Just remember, bending 22mm pipe you’d take off 11mm, and bending 28mm pipe you’d take off 14mm.
Thanks for this it is interesting
Great video. 👍🏾👍🏾
Thanks for that tutorial . very well explained.👍👍
You can heat up a needle till it’s red hot and press it through your fingernail to get that blood out.
Won’t get away with that on-site !!!
I would use a hybrid of both, the problem with the second one is you are doubling the tolerances for each measurement. I would take the off set off the centre line distance and then measure once (effectively using the McKeowen method but without two lots of inaccuracies from the measuring. Hope this makes sense?
i remember Mckewons way like speed limits of car
70 mph legal for 15 mm.
half 70 for 45degree third and 2 thirds of that tor 30 and 60 degrees
100 mph my speed illegal 22mm and repeat
Mckewons for me
Is there a way to do really small offsets, where a rad just doesn't line up with pre-existing pipes? It looks like the 60mm offset you did was about the limit, otherwise the bending tool doesn't have space to hold pipe between 1st and 2nd bends.
Hi just bend it less. Like 10 degrees and back 10 degrees see my recent video level 1 pipe bending offsets
@@Londontradecollege cheers. Just watching now.
Promo'SM 💘