machining silicon brass rod in 144" lenghts

I presume the amount is too small for rod suppliers to draw that diameter for you?

I would certainly be looking at changing the design to use the more commonly available diameter.

How precisely shaped does the rod have to be?

If your material temper is suitable and your product requirements can accept mill finish and mill tolerances, you should investigate the drawing process instead of machining.

TygerDawg
Blue Technik LLC
Manufacturing Engineering Consulting

What is the tolerance you require on the 1-7/8" Ø ?

I'd find a shop with a manual lathe with a hollow bore spindle.
They can use a Steady rest in place of the Tail stock and do it sections.
They will also need a stand past the lathe to keep the bar inline.

Thanks to all for your suggestions

Be sure you're looking at the correct material. C65500 is silicon BRONZE. C87500 is silicon BRASS. The two are not necessarily interchangeable (either from a mechanical or electrical perspective). That being said, the larger "copper" houses will either be able to draw a 2.00 inch diameter down to what you need themselves or have contacts within the industry where they can get it done (for a fee). End result is you get what you ordered.

It is possible to machine down a 2.00 inch diameter rod yourself - with the appropriate rests/clamps. If you can live with the shorter lengths (72 inch or so), cut the long rod down into the smaller sections, which are more manageable from a machining perspective.

Converting energy to motion for more than half a century

HI Gr8blu -

You and I are some of the few who know the difference between the two alloys. My background is actually in the copper base ingot business, where we produced these casting alloys regularly and cast them into ingot that were sold to foundries across North America.

If you might have any suggestions of who I could pay to draw the bar down, it would be appreciated. I have had no luck in trying to find anyone so far.

ds

Finding them or finding one that wants the business? I expect every mill that produces the stock can do it.