[mroy0404]

Hi guys


I have a print that states 32 surface finish, can one of you tell me what this looks like.

I should have mentioned the parts will be turned from 304 SS.

Is it possible to turn this finish

[mrainey]

Very slick - depending on the material, it can be challenging to hold a 32 finish on a production run of turned or milled parts.

[Tinmuk]

Holding a 32 finish in 304 is not hard. we routinely hold 12 -16 in CRES. the trick is to have the right nose radius and the speeds and feeds to match. In general the bigger the nose radius and the slower the feed, the better the finish.

That holds true up to certain point. if you are taking a big cut with big radius and too slow a feed, you will stall the machine.

so take a light cut (.005) with a rigid tool with a .012 or bigger radius with slow feed (you'll need to play around ) and you should be fine.

[NC Cams]

Here are some references to use as a visual comparison:

The ID of the big end of an automotive connecting rod (where the bearing fits) is roughly 40~60 micro inch (which is what I suspect you're units are).

The OD finish of a piston pin is roughly 6~10 micro inch.

The freshly honed finish of a cylinder bore is a bit rougher than what you're looking for but not much PROVIDING it is not a mirror finish like some guys use for racing.

If you have a record groove, it is WAY too rough,
If it is a mirror, it is WAY too smooth.

[Tim S]

There is a formula from Mitsubishi for calculating the surface finish you would get that I use when turning. The link to the page is below. 32 is not a problem.
Link for Formula:
http://www.mitsubishicarbide.net/mmu...n/formula1.htm