What's generally cheaper to do for a factory
- cut a disk from an aluminum rod and mill it for some time on CNC until it becomes a nice proper gear
OR
- make molds, cast aluminum into a gear shaped piece and mill it a little bit for a nice finish and accurate dimensions
?
It will depend on volume and needed material properties. Generally for very low volume/one off or prototype parts machining from stock is done. For mid to high volume casting may be one of the options chosen.
Well I asked about a factory, hence about production.
castings is cheaper.
next question?
> next question?
What casting method would be the best one? Lost wax or whatever? How is that wax copy of the gear is being produced?
die cast would be the cheapest route, an actual steel mold and liquid is pushed in at high pressure (reduces bubbles). Elon's gigapress is about making integrated car components from a single casting.
"Factory" isn't synonymous with mass production.
Neither is "production" hence the qualifier "mass" to describe a high level of output for any given time. You didn't specify or imply any quantity higher than "a gear", and need to learn to be more precise when asking technical questions.
Also, regardless of how many items a factory produces, the physical properties of the finished part may depend a lot on other operations you dont even mention that stabilize the material on a molecular level. Those add costs whether they are done to individual castings, or a billet that gets carved into the same shape.
It depends if you’re just wanting one gear or not really. Also don’t cast your own aluminum at home.
Manual work is probably good if you only need like one or two of these. CNC is good for repeatability.
Also chances are you can probably just buy this gear somewhere
>don’t cast your own aluminum at home
why
Its comes out with a lot of slag and the metal parts are not uniform, some parts are soft and some are hard. It can be bad if you try to machine it because the slag will dull your cutting tools. Not the end of the world for many dumb items like machine bases.
what were those paki's casting
While i dont like aluminum i have seen it used in cheap gears. Makes more sense in pulleys but ok.
Somewhere, probably buried on bikeforums.net is a good discussion about dropouts, and it goes into the various production methods. Stamping, casting, forging, cnc, etc.
>What's generally cheaper to do for a factory
Go to Boston Gear and order the gear you need.