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Steam
4th January 2008, 10:24
I need to put some bars on my bike to stop the soft panniers going into the wheel.
What's a good simple way to bend pipe or box for the home handyman?
It doesn't need to look good, just needs to work.
You can see what I plan in the photos, in red. There are good bolt-holes already there to bolt it to, very convenient.

Thanks in advance for your tips or suggestions!

The Pastor
4th January 2008, 10:30
you can get small pipe benders from supercrap for less than 20$, all they are is a radius to ben the pipe on.

Or you could just weld it together.


If the pipe is small enough you could just put it in a vice and beat on it.

Crisis management
4th January 2008, 10:31
Simplest and most effective way is to hire a manual pipe bender from your local hire shop. Try your local pipe supplier for hydraulic pipe and bend away happily.

xwhatsit
4th January 2008, 10:49
Would those pipe benders from hire shop do exhaust tubing?

Rosie
4th January 2008, 10:52
Clint640 made some pannier racks for my sherpa from 1/2 inch tube I bought from Hydraulink. http://www.advrider.com/forums/showthread.php?t=274521

We got them powdercoated to match the colour of the frame, and they look (and work) really well.

tri boy
4th January 2008, 10:58
You can pour dry beach sand into the pipe. Pack it lightly, and cap it with wood plugs.
Heat and bend the pipe/tubing with an oxy set, paying attention to add more heat to the outside of the bend. The sand stops the pipe collapsing while the metal reshapes itself. Great way to make complex header pipes from scratch.
Plus its cool to brag about your artistic bending skills.:yes:
An Orange glow on the metal is a sign that its close to bending temp.

trumpy
4th January 2008, 11:01
You are proposing to some quite tight bends so if you are going to do it yourself you can limit the flattening on the bends by filling the tube you are bending with sand. Just sellotape up the ends and pour the sand out when finished.

Steam
4th January 2008, 11:10
You are proposing to some quite tight bends so if you are going to do it yourself you can limit the flattening on the bends by filling the tube you are bending with sand. Just sellotape up the ends and pour the sand out when finished.

Aha! That's a good tip. Cheers.

So are the others, very interesting things.

Disco Dan
4th January 2008, 11:46
Used to use a pipe spring for bending copper pipes - just insert the spring and bend it with your hands, spring wont compress and flatten the pipe.

Firefight
4th January 2008, 11:50
Used to use a pipe spring for bending copper pipes - just insert the spring and bend it with your hands, spring wont compress and flatten the pipe.


shit you must be old,

I got a set of those in my workshop, most the kbers who stop by ask what there for:crazy: If you ever need to borrow them, give me a yell.


F/F

Disco Dan
4th January 2008, 11:54
shit you must be old,

I got a set of those in my workshop, most the kbers who stop by ask what there for:crazy: If you ever need to borrow them, give me a yell.


F/F

Nope, not old. Just one of those people who listened and watched their dad when I was a child. :yes:

My dad still has his set! So simple but it works wonders!

Firefight
4th January 2008, 11:57
listened :

My dad still has his set! So simple but it works wonders!


Your dead right Dan, simple as,

don,t see many round anymore,

last time our plumber came round to fix some shit at home, he didn't even know what they were when I showed him my set !


F/F

imdying
4th January 2008, 13:47
Naw, pipe springs are still very common, ask any HVAC engineer.

xwhatsit
4th January 2008, 13:49
Naw, pipe springs are still very common, ask any HVAC engineer.

How do you bend your exhaust pipes?

imdying
4th January 2008, 14:20
Either make them from stainless mandrel bent donuts and 90 degree bends, or make it any way you like, then have the machine scan what you've made in in 3D, and it spits a mandrel bent stainless bent tube out the other end :yes:

xwhatsit
4th January 2008, 14:41
Welding bits together typically looks like arse on a naked bike, though. It would even show through black coating?

Attached is the kind of look I want to avoid.

P.S. sorry about the minor thread highjack. I suppose it's somewhat relevant :D

imdying
4th January 2008, 14:43
Then just make them up like that, and have the 3D scanner/pipe bender thingy make them out of a single mandrel bent piece :yes:

If I were bending up a subframe like you're talking about (and I will be, for that same purpose as you), I'd be using either the 1/2" or 5/8" pipe bender I have :yes:

imdying
4th January 2008, 14:44
These ones are made from seperate pieces.

Steam
4th January 2008, 16:53
Attached is the kind of look I want to avoid.

I wonder how Britten did his sinuous intestine ones? Is that the kinda seamlessness you are going for?

Ocean1
4th January 2008, 17:03
I've used 5/8" hydraulic tube for racks, if you've got the right bender it's a snap. If you haven't it's invariably ugly.


I wonder how Britten did his sinuous intestine ones? Is that the kinda seamlessness you are going for?

A local guy's been making very tight exhaust-tube-dimension doughnuts for ages, you just cut the req'd pieces and weld 'em up. It's the only way you can really get sweet curves without seriously expensive tooling. Prety sure they're available from some of the auto-distributor places.

geoffm
5th January 2008, 08:32
An exhaust shop can bend tube for you - our locla charges $5/bend IIRC. You can also buy premade bends - Staniless Alloys do stainless ones.
The $200 pipe benders that use a 10T jack don't work on exhaust tubing - they are made for water pipe. Work well for that though, if you don't mind the extra wall thickness
Geoff

scumdog
5th January 2008, 09:40
You can pour dry beach sand into the pipe. Pack it lightly, and cap it with wood plugs.
Heat and bend the pipe/tubing with an oxy set, paying attention to add more heat to the outside of the bend. The sand stops the pipe collapsing while the metal reshapes itself. Great way to make complex header pipes from scratch.
Plus its cool to brag about your artistic bending skills.:yes:
An Orange glow on the metal is a sign that its close to bending temp.

ALWAYS always make sure the sand is as dry as a camls back..Any moisture MAY flash-steam when it's heated and MAY cause a filling of the Y-fronts (and worse) when the expanding steam splits the pipe.:doh:

sAsLEX
5th January 2008, 10:26
These ones are made from seperate pieces.

Saw a wastegate pipe once on a "really big bike...." that was made out of 27 odd triangular pieces of metal bent and welded, looked immaculate. There is no end to what the talented can do!

Ixion
5th January 2008, 10:32
Don't use beach sand unless you have no choice. It's very hard to clean the salt residue from the inside of the pipe afterward, and it can cause subsequent corrosion. Get some salt free dry sand from a builder's merchant.

AllanB
5th January 2008, 10:44
I wonder how Britten did his sinuous intestine ones? Is that the kinda seamlessness you are going for?


I read that each set of pipes took him 40 hours to make by hand. Lots and lots of little curves & cones all welded together.

I wonder if his kids ever saw him........

AllanB
5th January 2008, 10:49
Pipe below, the second picture took the bend out of my pipe......

offrd
5th January 2008, 14:57
I used solid bar for the ones i just whipped up this morning, Bits of flat bar for tabs to bolt to the bike, Mig and used gas to do the bends..:done: Easy as!

Not worth a million bucks but do the job!

Photos here http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=81666&d=1199496821 http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=81667&d=1199496821

xknuts
7th January 2008, 21:35
Simplest and most effective way is to hire a manual pipe bender from your local hire shop. Try your local pipe supplier for hydraulic pipe and bend away happily.

Thank you


ask any HVAC engineer.

But whats HVAC??


ALWAYS always make sure the sand is as dry as a camls back..Any moisture MAY flash-steam when it's heated and MAY cause a filling of the Y-fronts (and worse) when the expanding steam splits the pipe.:doh:

Is that like a brown eye in the Y fronts? Good advise, Scummy

rwh
7th January 2008, 21:42
But whats HVAC??


Heating, Ventilation and Air Conditioning

Richard

Bass
8th January 2008, 10:50
I used to design and build tuned pipes just cos I could. I was pretty anal about cross sectional areas, ground clearance, weight and stuff like that and so almost never used bends done in a commercial bender of any sort. Basically the bending dies are never a good fit for the tube that YOU want to use and so the pipe is crushed to some degree. However, if that doesn't matter to you, the simplest way is to buy commercially done bends, then cut and weld to suit.

If it does matter, then the sand AND HEAT method mentioned in here, including all the advice about sand selection, is the most versatile method because you can have any reasonable radius that you want or even any change of radius along the bend, if you so desire. Also you can take a fairly long length of pipe and sculpt it pretty much any way you please.
Further, this technique is quite easy to teach oneself and you will get proficient quite quickly. You will also find that a butane torch run off your barbecue gas bottle is adequate for small diameter or thin walled tubing. You can teach yourself to braize (sp) (not weld) aluminium with it too and do the whole thing in ally if you wish. There is a huge range of ally tube available out there. I recommend Weldwell Allyflow if they still make it, as the braizing rod. I got so I could braize 4 thou beer can with that stuff.
No matter how you go about it, note well Triboy's comment about more heat on the outside of the bend.

cooneyr
27th January 2008, 19:31
I'm all for the 10mm bar with 25x3 flat for bolting it on. Made two tail racks and three sets of pannier bars. Never had anything bend and works well.

Cheers R