Cheapest way to make a part?
Cheapest way to make a part?
(OP)
I have a part which is a 3/8 X 3/4 X 9" aluminum bar which has 8 irregularly spaced inline 7/16 tapped holes. I'm attempting to determine the cheapest way to manufacture lots of 1000 or more. I was thinking of multiple spindle drills vs gang drilling vs NC drill. I need to determine how many could be done per hour.





RE: Cheapest way to make a part?
That way, the limit on throughput is the time it takes to unload and reload the fixture. You should be able to do 20..50 parts in a cycle with a simple fixture on a modest mill. The lower number is if you have to mill both ends of the bar.
If you do, it may be quicker (than sawing and handling short bars) to load long stock into the fixture and mill across to separate the parts.
Mike Halloran
Pembroke Pines, FL, USA
RE: Cheapest way to make a part?
If it's not that high, the NC machine will likely be your best friend, especially if you already have one in house.
RE: Cheapest way to make a part?
Why limit yourself to machining? Cheapest for high volume would probably be some sort of casting or possible metal injection, with cast threads or threaded inserts.
"Art without engineering is dreaming; Engineering without art is calculating."
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RE: Cheapest way to make a part?
It might be someone out there making similar parts with all the investment in machining already done.
RE: Cheapest way to make a part?
As to the outsourcing, I would have to find someone producing a similar part, unless it was an NC job hich could be modified easily. My experience with outsourcing a few years was that it was cost prohibitive. To avoid the investment in equipment, I've found leasing the machine to be a preferred option, although I would still have the labor and consumables to deal with.
There is nothing complicated about the part, standard threads, 6061 material. If I knew the total annual volume, I would not have a need to pose the question.
Which is why I'm leaning toward the NC option to begin with, then if the volume ramps up, I like the dedicated machine.
RE: Cheapest way to make a part?
There are many hidden costs in making the part yourself: Logistics (handling raw material suppliers), maintenance and set up, breakdown costs, etc.
These are very difficult to put in the balance that is why they are easily forgotten until the day that they start bitting your profit.
I am just saying htat you should notrule out htis possibileity just because some years ago the cost was prohibitive.