Seeking best finishing process for 303SS shaft...

[quizzical1]

Hi All,

We're seeking the most suitable finishing process that will produce an 8uIN finish (for use with a Variseal) on a .154/.152 diameter x 4.00" long 303 SS precision ground shaft (e.g. McMaster Carr # 88915K42). I've been told: electro plate, electropolish and chrome plate. Any validity to these?

Thanks in advance...

 

[grinderguy]

Any process that puts chrome plating on stainless steel is tough to do. The plater may tell you he can "level" the finsh. Many times the plating just makes the flaws look worse. Electopolish has looked very good to me. Many of the medical parts I grind are later electropolished. Maintaining the finish before the electropolish can be done with a centerless grinder. AGM does that process. The electroplater will tell you what finish they want at the beginning of the process. The most econommical finsh from the centerless operation is a 32 micro. It is not a common procedure to put a tolarance on the microfinish but I would recomend that it be done. The 16 microfinish does not cost much more. I would ask for a 32 micro before electroplating. The other method is to treat it like jewelry and polish it in tumbling media or by hand with rouge. The quanity of parts and the handling requirements will be important. Sometime it cost us as more to handle the part to protect the finish than to grind the part into a loose container.

Robert Setree

http://www.advanced-grinding.com

 

[unclesyd]

Before you go to a lot of work contact these people about your precision rod.

http://www.bostoncenterless.com/stainless.htm

 

[unclesyd]

303 SS isn’t the best material to work with and can be especially troublesome in any plating process. Aside from purchasing finished bar I think a mechanical approach would be better.

I seen these peoples’ work and it is very good. I would contact them and see if it is feasible to micro finish a part your size.

http://www.impco.com/Microfinishing.htm