??Machined Aluminum?? How does it work?

Mr. No Stripes

Hello,
i know several members that have machined aluminum parts. I was just wondering how its done? what type of machine is used?

Thanks

temponaut

I'm sure some members with actual experience machining aluminum will chime in momentarily, but in the meantime, here are some reference videos and articles that might provide some of the information you're looking for:

Machining Aluminum Videos

"How to Machine Light Metals"

"Machining Aluminum"

pennausamike

Machining any material is basically using cutter tooling to shape a raw material into a finished product.

An example would be the Dobson pistol I machined out of aluminum flat stock and round bar.



I used a lathe to turn the "barrel" and "slide" shapes, a vertical mill to cut the "frame" and the various small pieces, and used files and emery paper to deburr and final shape the parts.
I drilled and tapped some of the parts to bolt them together.



Mike

Mr. No Stripes

wow, so you do this by "hand" with the tools or does a computer do it?

how do people make copys of their work in aluminum?

exoray

In short there are different tools for different jobs...

A lathe does most "round" work, but some are also fitted for milling operations...

A milling machine does most 'flat' work, but with additional attachments, tooling, and/or multi-axes CNC controls it can do a bunch of contours and even a lot of what was traditionally done on lathes...

There are laser cutters, waterjet cutters that can rough out cuts with precision and there are plasma cutters and traditional saws that can also rough out stuff but precision lacks...

There are EDM machines, both wire and sinker/plunge... With wire EDM it's a very fine brass wire with an electrical charge and it slices through conductive metals like a cheese cutter, with CNC controls you can get some fantastic cuts... With sinker/plunge EDM you machine a shape out of a special material and charge that puppy up with electricity and sink/plunge it into the metal and it burns itself into the metal leaving a negative of itself burnt into the metal...

These are the most common tools in a metal shop, there are other specialty ones but the above will accomplish just about any task you have to do...

There are some very talented manual machinist out there that can do a lot without computers, but in todays market and world most things are easier and more cost effective to have done on CNC machines, unless it's real simple...

Hit up youtube and type in

lathe
milling machine
wire EDM
sinker EDM or plunge EDM
laser cutter
waterjet cutter
plasma cutter

There are a bunch of videos that will give you an idea on how they work...

I have been lucky enough that I have got private tours of a full scale aerospace machine shop and been able to watch these machines in action, it's simply phenominal to see them work...

pennausamike

No computer machining in my world.
It's all dials and indicators and mics and mechanical stops.
To make more than one of something, I set stops and make multiple pieces with one set-up.
But once I tear down to move on to the next step, there is no going back without making a whole new set-up.

Google image "bridgeport mill" and "metal lathe" to see what these basic machine tools look like.
Google image "lathe toolbits" and "end mill" to see the cutters that act on the material.

It takes the average machinist about ten years to be accomplished in the field. A lot of machining is knowing what to NOT cut away in the process order so that you can measure and hold the piece you are working on.

I have never made a decent return on any hobby project I've machined; at least not in the sense that I couldn't have made more money just doing my job. I think the best I ever did was about $8.00/hr. and I assure you I make more than that.
Machining is one of the most under-appreciated skills in the US today.
Businesses always bemoan the lack of skilled machinists but then they pay very poorly relative to the skills and responsibility required of machinists.
That's why I'm now a maintenance mechanic...

Mike

Mr. No Stripes

fascinating!
So when company's manufacture tools and such that are made out of aluminum, they would be using diecasting correct, not machined aluminum?

I know some guys that make Aluminum Fett parts, like the gauntlet darts... how do they get them to look so perfect to the original found part, they don't do those by hand do they?

pennausamike

I think you are confusing a mass produced item like tools with a one-off specialty item like a movie prop.
Different methods of manufacture are applied to an item to be mass produced
than an item that is a one-off embodiment of creative design.
Also, the term, "by hand" implies human powered tools like a file or a hacksaw.
Machinists use powerful tools with manual or power feeds,
but all inputs are from the operator in the case of manual machining.
CNC machines are programmed to move the workpiece or the cutters to form machined shapes.
Once the machine is programmed and set up,
the operator doesn't interact with the machining process until the cut is done.

So, in the case of Boba Fett's darts, the originals were likely done by a manual machinist on a lathe.
A hobbiest-machinist could duplicate the original parts with manual machines and they'd look as good as the originals.
But if someone wanted to reproduce and sell 100 or a 1,000 of the darts,
they could supply the dimensions to a CNC shop,
which would translate the dimensions into a program and a machining center could crank out part after part.

Normally, for a short run of complicated parts requiring odd set-ups and hand-fit shapes,
manual machining is the most accessible and cost effective way to go.
The last time I worked in industrial machining, manual mill time was $40/hr and CNC mill time was $95/hr.
When I put my Jayne LeMat on eBay,
I put a Buy-It-Now of $600 to represent the cost of making one at a shop rate of $40/hr.



I got $280 for it.
Which I could afford to take, but it didn't make me happy.
(Well, kinda; cuz I financed some other purchase with the money...)

Mike

Mr. No Stripes

Ok, that makes alot more sense. For some reason I was thinking something along the lines of wood carving with intense power tools, so it didn't make much sense, but now I get it.

Looks like you've done some beautiful work. Very well done. Thanks for sharing.

exoray

Actually the tools are not that much fancier or intense then wood tools you just cut MUCH slower, ie take off much less with each pass... And they are more rigid...

Yep it's not cheap, I get the cash under the table discount and it's still not cheap... And CNC doesn't always mean fast...