I am looking at a use for some spring-temper 304 stainless wire, .009"
dia. It comes round, but it would be better suited for this use if it
was square-section. Can I run it (cold) through a couple pairs of
rollers to form it into a square, without altering the other properties?
Alternately does anyone sell smaller quantities of such wire (~1-lb
spools). I see there is flattened wire (about a 2:1 height/width ratio)
but it appears to be once-rolled with the ends rounded from forming, and
I want a (roughly) square cross-section with fairly sharp edges.
If you deform metal, it will work-harden. So, no, you can not roll it
without changing properties.
There are places that make square wire, for example:
A lot of custom spring companies will make springs with square wire, perhaps
they will sell you small quanitites of such.
However, my experience as an engineer is that when you think you need
something really unusual, then you are either not clever enough or too
clever for your own good. There are very rare exceptions when working on
really cutting edge stuff. In other words try to find a way to make do with
I may try to do this with some soft-temper wire I have around,,,, maybe
it will approach the spring-temper when done.
Generally I've not had good experience with such queries.
If it wasn't for the unusual things, I wouldn't be doing anything at all....
Norton is sharing wisdom.. it shouldn't be too difficult to accept. Finding
an existing spring product would be your best option.
I worked in plant maintenance at a steel wire mill facility. Soft mild steel
wire (nails, large staples, MIG wire etc) is fairly difficult to resize
and/or reshape, highly technical and the machines are generally
The flatteners I saw used numerous (dozens of pairs of) rollers just for one
Shaping or sizing gold or silver jewelry wire is more along the lines of a
Reshaping stainless alloys and high carbon steel would be many times more
difficult than mild steel.
Spring temper and 304 stainless steel is an oxymoron. One can't
harden 300 series SS with a heat treat. It will work harden but that
will change it=92s magnetic properties..
If one needs corrosion resistance and non magnetic properties I
suggest looking at NiTinol. Buy a sheet then water jet cut strips.
I haven't seen 304 spring wire but have seen and used 302. And I know
the way 302 is made into a spring is just through drawing. So the soft
wire is work hardened. If you draw 304 wire through a die I imagine it
would work harden too, considering that you can apparently buy the
round stuff. Jewelry suppliers sell dies for round and oval wire
drawing but I have not seen any for square. .009 round wire and .008
square have virtually the same cross sectional area so maybe you could
set up some bearings (like you suggested above) but instead roll the
soft stuff into hard. Run it through several times to work it a lot.
From what I understand spring temper means its fully work hardened. However
roll forming would be a form of working so if you set up a roller that will
work for you to form it into square wire it will harden more if its not full
hard. I don't see why you couldn't do it with larger wire, but I am having
a hard time visualizing something that will work with such small wire.
Well, something I could setup in my shop anyway. Maybe a series of
alternating direction parallel roller pairs to draw the wire through. Each
pair only a few 1/10000 close together than the last pair. Plain cold rolled
steel might work for a little while if it?s a small job, but it will groove
from the wire pretty quickly if it?s a bigger project.
Not sure, maybe a harder stainless or even titanium for the rollers if its
to produce larger quantities of square wire?
Regardless I am pretty sure you will lengthen and reduce the gage of a wire
by using this particular process.
How long of pieces do you need? For short pieces you might be able to just
press them into a machined groove in a metal plate with another metal plate
using a hydraulic press. They are going to curl rather severely I think
when pulling them out of the groove, but I bet you could get square wire
(roughly depending on your math skills) this way too. One side will have
squarer corners than the other I suspect also. Or you may just wind up with
a plate with a nicely pressed in stainless strip. LOL.
Try it and let us know how it works.
Round carbide inserts are readily available, eg see links at link
below for $5.50-each to $19-each inserts. Minor challenge: they have
7-degree tapered sides for clearance, ie, are like sections of a cone.
So, would need to reverse one of each pair of rollers so that angles
complement each other, and would need to tip the axles 7 degrees to
avoid twisting the wire as it passes between the rollers.
I would need continuous lengths (thousands of feet) and the process
would need to be quick and easy. That's why I thought of the
bearing-rollers. -Which is not really "drawing", I suppose, but anyway.
I know it normally takes a lot of pressure to power-roll metal, but this