Exercize In Futility

[Ronno6]

A guy advertised machine shop work on the local FB
I asked him how I would go about getting a quote, and ASKED him what tolerances he could work with........
He said to send him a sketch w/dimensions, and NEVER replied about the tolerances.

So, I sent him pictures and dimensions for a couple of parts, specifying +/- .001", 125 micro inch finish........
From my mechanical purchasing days, those were STANDARD commercial tolerances........
He about had a cow!!
Said he couldn't work that tightly.......
So I reminded him that that was maybe the SECOND thing I asked..............

He has gone away now in short, sharp, jerky movements.......
Or, maybe he flew around in ever decreasing circles til his head flew up his own..................

[Ronfiveo]

I worked in a machine shop for years and if I remember right, +/- .005 with a 125 machine finish was
the standard for ordering a production part that would be on a mass produced scale.

However, +/- .001 could be ordered on a higher price scale. That's close to a
press fit. The higher price would be to cover the unavoidable higher scrap percentage.

And a 125 finish is standard machine finish, but a 63 finish is very shiney with less tool marks per inch, and a 32 finish
was like chrome or glass.

Or is it the other way around. It's been 40 years.

It's been a very long time but you brought back some fond memories.

Ron

[pan60]

to funny when i am doing mic parts we hold way tighter then those.
i am currently doing a item and holding +/- .0005

[Ronno6]

He was advertising CNC work.
I wold think that +/- .001" would be slop work for CNC........

[nced]

I worked in a machine shop for years and if I remember right, +/- .005 with a 125 machine finish was
the standard for ordering a production part that would be on a mass produced scale.

However, +/- .001 could be ordered on a higher price scale. That's close to a
press fit. The higher price would be to cover the unavoidable higher scrap percentage.

And a 125 finish is standard machine finish, but a 63 finish is very shiney with less tool marks per inch, and a 32 finish
was like chrome or glass.

Or is it the other way around. It's been 40 years.

It's been a very long time but you brought back some fond memories.

Ron

Very interesting thread! LOL, "higher price would be to cover the unavoidable higher scrap percentage" describes my "seat of the pants" machining using a Chinese bench top lathe and my "whittle down till it fits" machining style.........

[Ronfiveo]

I wish I had a set up like that. Very nice.

That's would be my way of machining. It's takes longer to whittle it down but you
end up with a machine part that fits right and works like it should, like you did.

Nice job.

Ron

[glassman98]

to funny when i am doing mic parts we hold way tighter then those.
i am currently doing a item and holding +/- .0005

Pan60
What type of a machine are you doing your +/- .0005 on? I thinking a grinder.  Craig

[pan60]

to funny when i am doing mic parts we hold way tighter then those.
i am currently doing a item and holding +/- .0005

Pan60
What type of a machine are you doing your +/- .0005 on? I thinking a grinder.  Craig

some but not all. micropone capsules are supper tight just a few microns

[pan60]

to funny when i am doing mic parts we hold way tighter then those.
i am currently doing a item and holding +/- .0005

Pan60
What type of a machine are you doing your +/- .0005 on? I thinking a grinder.  Craig

p.S.
here is a product that parts are held to .001 and if i could find someone who coud do these at what i want with out breaking the bank they would be .0005 that is what they where speced out but i guess only ones that met that spec was the one we made n house wich would have been maybe 30 units.
the rings that hold the filters are where the tolerance is.

http://www.petesplaceaudio.com/blast-pad-mic-pop-screen

[JPSAXNC]

Most of the time, the finish left by a properly cutting tool is smooth enough. Unless it's going to be a bearing surface

[JPSAXNC]

CNC is not more accurate than a conventional machine, just faster and with more options.

[Ronno6]

I purchases a second Hardinge DVM 59 turret lathe yesterday.
These machines, once set up to manufacture a part,will turn out part after part,
very quickly, dimensionally accurate and each one identical to the one before and the one after......

Hopefully, when my machining days are behind me, I can sell them for as much I paid.......

[pan60]

I purchases a second Hardinge DVM 59 turret lathe yesterday.
These machines, once set up to manufacture a part,will turn out part after part,
very quickly, dimensionally accurate and each one identical to the one before and the one after......

Hopefully, when my machining days are behind me, I can sell them for as much I paid.......

dont give away all my secrets : )

[Ronno6]

I purchases a second Hardinge DVM 59 turret lathe yesterday.
These machines, once set up to manufacture a part,will turn out part after part,
very quickly, dimensionally accurate and each one identical to the one before and the one after......

Hopefully, when my machining days are behind me, I can sell them for as much I paid.......

dont give away all my secrets : )

Payback.......

[pan60]

LOL
oh i see how that works : )

[Ronno6]

LOL
oh i see how that works : )

Yeah, you get the credit for this one.....