Bending 28mm Copper pipe by hand??

Oct 10, 2018 16 Replies

Hi All I have a plumbing job to do at some point which will include bending so me 28mm Cu pipe (to a water tank. I have a pipe bender somewhere in the lof t or garage - one of the large-ish two-handled design - and had presumed to use that. However on checking these out recently I see that they tend to o nly do 15mm and 22mm!



What to do? I am a little weedy and did not make a good job of bending even 15mm pipe using a bending spring, years ago. The larger machines are 50qui d or so a day to hire which seems OTT. Any other solutions?



Cheers J^n


Heat the area you want to bend to cherry red and plunge into cold water, it will then bend fairly easily but you'll need to either use a spring or pack it tightly with sand to prevent the pipe collapsing as it bends. Alternatively, find a friendly plumber.

some 28mm Cu pipe (to a water tank. I have a pipe bender somewhere in the l oft or garage - one of the large-ish two-handled design - and had presumed to use that. However on checking these out recently I see that they tend to only do 15mm and 22mm!

en 15mm pipe using a bending spring, years ago. The larger machines are 50q uid or so a day to hire which seems OTT. Any other solutions?

pipe benders get you leverage, but still bending 22mm may be too hard if we edy. And IME the amount of force for 22mm is pushing it for a handheld devi ce. So 28mm would not be a hand-held machine's thing.

You can get hydraulic presses or weld a frame together & use a car jack. Th en use I forget the name but it allows pipe bends with one. But why not jus t use elbows etc?

NT

g some 28mm Cu pipe (to a water tank. I have a pipe bender somewhere in the loft or garage - one of the large-ish two-handled design - and had presume d to use that. However on checking these out recently I see that they tend to only do 15mm and 22mm!

even 15mm pipe using a bending spring, years ago. The larger machines are 5

0quid or so a day to hire which seems OTT. Any other solutions?

weedy. And IME the amount of force for 22mm is pushing it for a handheld de vice. So 28mm would not be a hand-held machine's thing.

Then use I forget the name but it allows pipe bends with one. But why not j ust use elbows etc?

parallelling smaller pipes may also be an option.

NT

Buy an elbow, cut the pipe, and solder it in:

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Is the correct answer. It's called annealing. Best to buy a spring rather than use sand.

22 mm in a Hilmor bender is OK provided you don't expect to just push the handles together between your hand/arms. I normally work it against the floor or some other imovable object. 22 mm and a bending spring is really hardwork and not very accurate. It might be OK if you have the abilty to anneal the pipe first, that is heat to cherry red over the entire length of the bend at the same time then quench it. Yer average hand held blow lamp can't do that.

I doubt that 28 mm is doable with either of the above methods. I think you'll need a hydrualic bender of some sort.

Properly bent pipe looks nicer? Offers less resistance? Generates less turbulance in the flow. You can get 28 mm long radius bends but they don't look as if the radius is that of a Hilmor.

My thought were initially like yours, but after looking up the annealing temperature of copper and finding its 400C, annealing and subsequent bending looks quite doable.

There seems a general consensus that once annealed it seems possible to bend using a spring. It might be that the pipe work hardens in the process and has to be re-annealed.

Hum, that sent me off to google fully expecting to find consistent/colabatory information but didn't. Most places say heat to cherry red and quench but copper doesn't nessarily need the quench (wikipedia annealing). There was mention of watching the colour of the metal as you heat it and once past a plum red it has got hot enough. That's a surface colour of the metal BTW not a heat radiation glow.

If copper only needs to get above 400 C (plum red?) and doesn't need to be quenched to anneal then it should be possible to heat a small section of pipe and slowly move that along the pipe to anneal a longer section.

Copper is very soft when annealed but does work harden quickly. If you didn't form the wanted bend in a single smooth movement I think you'd have to re-anneal for a second or subsequent adjustments.

some 28mm Cu pipe (to a water tank. I have a pipe bender somewhere in the l oft or garage - one of the large-ish two-handled design - and had presumed to use that. However on checking these out recently I see that they tend to only do 15mm and 22mm!

en 15mm pipe using a bending spring, years ago. The larger machines are 50q uid or so a day to hire which seems OTT. Any other solutions?

You don't need a machine to bend copper pipe, these are a new thing relativ ely. Previously a "bending block" was used. A bit of 3" x 3" x 36" wood with a p ipe sized hole drilled near one end. The pipe is stuck in the hole and bent progressively working back and forth . However, it takes some skill.

You need the right grade of copper to bend it too.

Do you really need 28mm to a water tank? I have one here, and 22mm seems adequate.

If you really do, hiring a floor standing pipe bender would seem to me worth the cost.

I tend to agree, but alternatively do it in plastic?

I rather enjoy working with copper pipe and (trying) to make a neat job of bends. Very satisfying. Rather than the drooping plastic I seem to see everywhere. But I do have a decent pipe bender.

Me too. But not a 28 mm one. And even the 22, using stock (half hard) pipe takes quite a pull, especially if working away from a big bench-mounted vice. In the dim and distant past, when I had (other) possible pipe bending projects I took a look at hydraulic benders like this

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That looks pretty good value, actually. Doesn't seem to say what sizes it covers, though.

Strangely, specified in imperial

Thanks for all the replies... I am rather embarrassed ot say that I was fixating so much on the 'bending' bit that I had totally forgetten about using a 45degree elbow! That may well work, I will have to check.

It is actually to replace a pipe *from* a water tank (not *to*), and I don't want to change any other fittings, is the main issue.

I would love to have a try at annealing and bending that way, but I suspect that soldering an elbow is the way to go. I'll put my muscles away this time...

Cheers J^n

Its bigger cousin

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does 1/2", 3/4", 1", 1.1/4", 1.1/2", 2", 2.1/2", 3".

Which is a bit of a problem if you want a metric pipe bent. Also imperial sizes are a bit ambiguous because traditionally they were i.d. and the o.d. depended a bit on the pipe material and grade.

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