johnthepolisher

Topic: Vibratory finishing prior to electropolishing question

I'm finishng a bunch of 306 stainless parts which require manual polishing prior to electropolishing. I would like to eliminate a majority of the physical labor involved in the process by vibratory finishing. I was wondering if anyone has any information pertaining to the selection of the appropriate media for finishing the stainless prior to electropolishing.

DustinGebhardt

Re: Vibratory finishing prior to electropolishing question

How big are your parts?  Are you looking to vibe them with an abrasive powder or another type of media?  Are you trying to use regular vibe bowls or use high-energy vibe systems?  What final finish are you looking for?  What is the starting finish condition?


In my plant, we use regular vibe bowls to polish hardened hand tools (sockets).  We also use the vibe process to clean off the heat treating scale.  Our smaller sockets go into bowls with an abrasive aluminum oxide powder for a few hours.  Our mid-to-large sockets get run with a chemical accelarant along with a high-density non-abrasive media.  The finish on these bowls is outstanding (for us at least) with an Ra measurement between 5-12.  In the past, we've also used an abrasive plastic media along with the accelerant, but the finish wasn't as good.  We are transitioning away from that stuff and going to the ceramic nonabrasive stuff.  We typically start with an Ra as high as 25 and get it down to the 5-12 range within 2-3 hours (including burnish and rust preventative cycle time).


Our vibe chemical supplier is second to none.  I can send you his contact info to see if you'd like?  I'm not sure Ohio is in his territory, but he's a wealth of knowledge nonetheless.

-Dustin Gebhardt, CEF

Advanced Manufacturing/Finishing Engineer

Moen

Sanford, NC

johnthepolisher

Re: Vibratory finishing prior to electropolishing question

Hey Dustin, here is the scoop:

The 19" X 3" X 3/8" parts are cut from unfinished flat stock. The edges and the faces are pretty rough. I uploaded a picture of a couple of polished pieces to give you a better idea of what I am talking about...

I have a small bowl type vibratory unit which I use to finish small parts prior to chrome plating, but it is inadequate for the job at hand. So, I have been looking at purchasing a tub type vibratory finisher to handle the larger parts. Since I am new to mass finishing (but experienced in "old-school" polishing), I'm not really sure about the types of media/compound combinations would provide the best/fastest results.

I'm trying to go from a belted finish (course surface conditioning belt), to a finish that is suitable for electropolishing. Manual polishing and buffing takes roughly two and a half hours per piece, start to finish - which is way too long...

By the way, the parts in the photo were buffed, not electropolished. Electropolishing will eliminate the the extensive final buffing time, but I would like to reduce the manual polishing time as well.

As usual, your thoughts on this are greatly appreciated... 


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Tonzze

Re: Vibratory finishing prior to electropolishing question

you can have polish them at rotary polishing machine.

Jeddy Huang

www.tonzze.cn

Jeddy Huang

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Deburring & Polishing Machine

http://www.tonzze.cn