Bending brass rod

[David Boyce]

I wanted to order some 4mm diameter grand hinge pins, but Heckschers have none at the moment. So I have ordered some 4mm brass rod on Ebay.  Can anyone advise on the best way to make the right-angle bend, to make lengths of it into L-shaped hinge pins?

Best regards,

David.

[Ron Nossaman]

The best way? I have no idea, and likely wouldn't recognize it if I saw
it, but I know a way that works. Cut the brass to length (hinge width +
bend), and round the ends. Tape some maple or pinblock scrap to your
vise jaws to avoid marring the pin, and clamp the pin in the vise with
the end extending past the wood. With a hammer and another block used as
a punch, also to avoid marring the pin, hammer the free end over.
Ron N

[David Boyce]

On 11/11/2013 13:38, Ron Nossaman wrote:
> The best way? I have no idea, and likely wouldn't recognize it if I
> saw it, but I know a way that works. Cut the brass to length (hinge
> width + bend), and round the ends. Tape some maple or pinblock scrap
> to your vise jaws to avoid marring the pin, and clamp the pin in the
> vise with the end extending past the wood. With a hammer and another
> block used as a punch, also to avoid marring the pin, hammer the free
> end over.
> Ron N

Thanks for that, Ron. Good to know it can be done like that without
using heat and without the brass shearing. I was also looking at little
wire/rod bending jigs on Ebay. If I get good at it, I might also
consider being a bit more sophisticated and trying to make the little
L-shaped brass bookholders, which are now quite expensive.

The other day I was in a good hardware store we have here, a family
business. Some nice slot-head countersunk brass screws about 3 1/2"
caught my eye. They were £3.75 (over $5) EACH! It's made me eye with
renewed respect some boxes of brass screws I inherited that were my
father's....

Best regards,

David.

[Ron Nossaman]

On 11/11/2013 7:47 AM, David Boyce wrote:
>
> Thanks for that, Ron. Good to know it can be done like that without
> using heat and without the brass shearing.

Sometimes, sometimes not. It depends on the alloy. If it's soft 360,
you're in business. Otherwise, it's a crapshoot. If you have to heat it,
you'll have fun with a propane torch (tourch <G>) standing around
waiting for it to heat. If it comes to that, try drilling a hole in a
pinblock scrap, the depth of the bent over end. Leave the rod full
length, heat the end red, jam it in the hole (in the vise), and quickly
bend it over, tapping with a hammer to square it up some. You'll burn up
your "jig", but it is after all, scrap. Or use steel and not hurt the
jig at all, but it'll suck the heat out of the brass very quickly if you
don't heat the jig too. Then you'll have to cut to length and round the
ends of a much more awkward piece.

> The other day I was in a good hardware store we have here, a family
> business. Some nice slot-head countersunk brass screws about 3 1/2"
> caught my eye. They were £3.75 (over $5) EACH! It's made me eye with
> renewed respect some boxes of brass screws I inherited that were my
> father's....

I don't remember details, but some time back, a big copper mine shut
down. Word then was that all things copper and brass would get expensive
as a result (because they can, and there is an excuse). Now, it's like
gas prices. We've been trained to accept that all things copper and
brass are more valuable than silver, and prices reflect that. Scrap
metal places buy brass for around $1.50 here, and sell it for around
$5.00. New brass was over $8.00 lb last I checked. The screw pricing
just reflects a fine price gouging opportunity, that's probably cheap
ten year old stock marked up 7000%. Because they can.
Ron N

[Isaac OLEG]

I use a large vice, something to protect the rod if necessary (not with my vice as I can change the jaws ) 

A hammer to bend and flatten a little the small part.

Never had to use heat anyway for small rods. 

But it may allow to make a sort of eyelet or a more nice small part, as brass may crack if bend too much. I have no idea of the brass qualities, 

 it is not easy to have all the necessary diameters, some are 4.2 mm for instance - better not loose the original ones.

New rods are useful for vertical music desks, also. here also , rarely an exact diameter in my experience.

[Ron Overs]

David and all,

The success in bending without heat will depend on the type of brass and its condition. We buy free machining brass for workshop stock and it won't bend to ninety degrees without breaking unless it is heated before bending.

We have in-house-made forming tools for making lid pins with abnormal diameters. If the pins required are 4 or 5 mm it is much cheaper to buy them from a supplier. But if you require a special diameter you can turn nominal stock down to a specific diameter and make forming tools quite quickly.

We use 1/2" black steel rod for making forming tools (which are kept in a drawer for future use when required). Two forming pieces are made, one with a through hole which is slightly larger than the pin diameter, and another length drilled only to the depth required to accommodate the bent shorter piece of the finished pin. The piece with the shorter hole needs to be long enough to allow you to hold the brass rod while heating where the bend will be made, and to use it as a bending handle once the brass has been heated to the required temperature (dull red). Both the handle piece and the drilled through piece need to have a 45 degree flat chamfer ground at the end where the bending will be done, to allow the brass rod to be supported right to the bend as the bend is formed.

The procedure we use is:

Cut the rod to the length required for the hinge length plus the bent shorter segment.

Radius ends and polish with a buffing machine.

Place drilled through part of bending kit into vice with hole horizontal and with end protruding slightly from vice jaws, to avoid heating jaws and annealing them when heating the brass. The chamfered flat will be sitting with the chamfered face vertical to allow for clearance when the bend is made.

Place the brass into the bending handle, then holding it horizontal, withdraw brass rod enough to heat it before making the bend.

With the brass rod in the handle, the protruding brass is inserted into the drilled through piece which has been placed in the vice - leaving enough brass exposed to allow for the rod to be heated right at the place of the bend.

Using the oxy-acetylene torch, heat the brass to red at the place where the bend will be made, then quickly set the torch aside, move the brass into the drilled through piece while ensuring that the rod is fully pushed into the handle, then bend to 90 degrees plus a little more to allow for spring-back.

You should now have a nicely formed lid hinge which requires light sanding at the bend followed by a final buff.

Hope this helps. We've been making pins for many years, but where possible, we always use off the shelf pins when available. If anyone would like to see an image of the bending tools, let me know and I'll photograph them with my phone.

Ron O.

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[David Boyce]

Thanks for this Ron. 

Heckschers, my usual suppliers, stock three diameters of hinge pin. I had some of all three sizes but I recently used up the last I had of the middle, 4mm size.  When I called today they had none of that size in stock.  So as an experiment I have ordered 30cm of 4mm dia brass rod from a supplier on ebay.  I will see what it's like when it arrives, and let you know how I get on!

Best regards,

David.