Easiest way to bend 8mm brass/steel rod right angle

[Tetsuaiga]

I would like to bend an 8mm brass rod but am not really sure what sort of tool I'd need.

Does anyone know the easiest cheapest option?

I was thinking I could perhaps drill then use a tap and die set to install two steel bolts/rods into a section of metal then fit it into my bench vice, use a pipe as leverage to bend the rod between the steel pieces.

If there's something cheapish I could buy I'd be happy to save the time of building something. If steel is easier I can use that.

Thanks.

 

[Phil Pascoe]

Heat it red hot and put it into the vice with the end of the jaws where you want the bend and hammer it sideways. I wouldn't think you'd get the bend any tighter any other way - which I assume is what you're aiming for. Don't quench it unless you want it soft.

 

[Eric The Viking]

I think the biggest problem might be the appearance of the finished item. Is it going to be seen, or does it have to look neat?

I have some 8mm brass bar stock and it's really hard to bend by hand because of its thickness - brass work-hardens and becomes brittle quite easily. The other thing is the radius of the bend. You can get 8mm bending tools quite easily, for copper pipe (vehicle fuel pipes and plumbing), but the radius will be about 30mm probably.

Anneal it by heating until it discolours, to make it softer, locally. There are a number of YouTube videos about this, as shooters recycle their old brass cartridge cases, and have to re-form the necks of them from time to time. Search on "annealing brass".

If it has to look really neat, I'd try to find an engineering workshop locally, or a model engineering club, and contact them. There are 'bending brakes" for sheet materials, and they might have something similar for bar stock. Model engineers are a very inventive lot, and may come up with something for you.

Allow quite a bit of extra for mistakes and experiments!

E.

 

[Tetsuaiga]

Thanks for the replies.

Yes keeping a clean appearance is important. I might look into using steel instead, perhaps its less brittle than brass? At least certain types as i know theres a lot.

I can probably go down to 7mm but when i bought the rods before I just saw 6 8 and 10mm sizings.

 

[Sheffield Tony]

Grade of brass matters a bit; see here:

http://www.ukworkshop.co.uk/forums/fold ... 87803.html

CZ108 is easier to bend, CZ121 better for machining.

If you want a radiussed corner, your jig with the two pegs is tthe right idea. Here's one I made earlier

This was for forming the hook on bowl turning tools, so quite small/light duty, but the idea is the same.

 

[Tetsuaiga]

I'll keep the grade in mind. Is a pipe over the rod the best thing to use for applying the pressure?

Your jig is just what I was thinking of making. Probably worth a go before buying anything.

 

[Sheffield Tony]

I copied this idea from my dad, who used a larger version to form decorative scrollwork in mild steel for gates, etc. With this, he had a second tool consisting length of round bar as a handle with two similar pegs welded to the side of it at one end (like an elongated F shape), with which you can apply pressure close to where you want the bend, without generating a kink. A length of pipe might be worth a go though.

When making my jig, I was worried that the pins might bend. They are unhardened silver steel (I wanted to use it for hot work, so no point heat treating). The most likely point is where the pegs enter the block. Rather than threading the whole depth of the hole, the top bit is a snug clearance size before the thread starts, to avoid the bending force being on the threaded part of the pegs.

 

[Tetsuaiga]

Interesting, I hadn't thought of an F shape lever, i might just try drilling a matching 8mm hole in some hardwood and see what happens.

Thanks for the help.