> First is to extrude the shapes in long bars, that's where product design
> comes in. Next you have to slice the parts out of the bars. Because of
> the extrusion shape and the compound curves you can't band saw them, well
> the clamp parts can be sawed but the bridge can't. So my choice would be
> to wire or water jet them, laser is nice but much more expensive. So now
> we have the shape and we have the size, now cut holes, threads, and
> counters, toss them all into a tumbler and get your final finish, anodize
> them and boom your done. The set up for doing holes, threads and counters
> is much easier and faster and less tooling intensive than doing it all
from
> billet. Extrusion tooling is pricey ($5K each) but the advantage is that
> it can sit on a shelf until you are ready for the next batch. Most
milling
> machine tooling would be set up for each run and I guarantee it will
never,
> ever be the same twice, within tolerance, but not the same. You don't
need
> a huge indexing mill to do it efficiently either so a cheaper job shop
with
> CNC can do it.
>
Wire EDM cutting? Water Jet Cutting? These are spendy in comparison to
milling, but they are great processes. (WJC sure is messy though!)
Hmm. I toured Richland Specialty Extrusion this year, and they had some
pretty loose tolerances on their tubes, compared to Sandvik Special metals,
which uses pilgering for its seamless tubing. As far as the milling
operation, that has a lot to do with what kind of mill you are using, and
the state of tool wear, and who the operator is. I machined a precision
gyroscope last term, and I can garuntee you it is within a .0005" tolerance,
which is far closer than you would ever need for most any other project.
> 7000 series is easily extruded as is 6000 series, then again the same
> tooling techniques and costs will be involved to extrude titanium, only
> material costs will go up there.
>
Titanium and Zirconimum are generally unsuitable for extrusion due to their
crystal structure (hexagonal close packed, it cracks under the residual
stresses imposed during the extrusion. Pilger rolling is the preferred
process). The government found this out the hard way. They built the
worlds largest extrusion press to extrude zircoloid tubing to use as nuclear
fuel rod cladding, and discovered that the process was seriously flawed
after conducting a couple of runs. They now lease that facility to Richland
Specialty Extrusion, a division of Kaiser Aluminum. I've seen it in
operation, its great. They take these aluminum billets that are about a
foot in diameter and two feet long, then press that out into a 40 foot long
tube, which then gets shipped off to Easton Sports who draws that into
softball bats.
> So who's up for taking this design to production? I'll do all the design
> and FEA work, I'll provide the prints and I get 5-10% royalty, hell I'll
> even middle man with the shops I normally work with. Not interested in
> patents, but I am putting this all down on paper and will mail it to
> myself, certified mail so don't think about borrowing my ideas without a
> whooopin.
>
Are you a P.E.? Don't you have an intellectual property contract with your
company? I'm sure they will take a piece of that too, even if you did think
it up on your own time at home. You know, the problem with patents is that
once you apply for one, your design is out there for everybody to see, and
unless you have lots of money for a good legal team, your idea can get
stolen. I did some work for a associate professor who owns his own company.
They are designing and producing power converters to use with fuel cells,
and he is afraid of applying for a patent for that very reason.
Jeff