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  1. #21
    Hi Guys
    Just out of interest, how will you be gauging the thread ?

  2. #22
    Quote Originally Posted by mekanik View Post
    Hi Guys
    Just out of interest, how will you be gauging the thread ?
    With a thread gauge (like a pocket knife with thread patterns cut in the blades)
    you could use a camera if your cnc has one... If it is M12 it can only be one of a slack handful pitches

  3. #23
    Hi Mark
    That only lets you know you have the pitch right, what about the effective diameter.
    in another life i used top be a mechanical inspector in a machine shop and we had the luxury of screw ring gauges, i have thread parallels @ home but find them very fiddly in use.
    Regards

  4. #24
    Ah, so it was a loaded question then?

    I would take it to Gandalf the Gray and ask him what the angle of the dangle was :)

  5. #25
    I was thinking of offering to make them, but without a proper gauge it's not an option really, also the PEEK is GBP75 for 22mm Dia Bar so that only GBP75's worth of beer tokens
    PS angle of dangle will be 60deg for Metric thread
    Last edited by mekanik; 16-06-2013 at 12:07 PM.

  6. #26
    Quote Originally Posted by mekanik View Post
    I was thinking of offering to make them, but without a proper gauge it's not an option really, also the PEEK is GBP75 for 22mm Dia Bar so that only GBP75's worth of beer tokens
    PS angle of dangle will be 60deg for Metric thread
    IF my memory serves me 22mm wouldn't cover the full standard M12 hex head, it would need to be 25mm rod (next standard rod size up)
    as an "M12" surly it can only be ISO1.75 or ISO1.25 for fine... I'm not with you on the "proper gauge", what is a "proper" gauge and in what sense would you need one? (just out of interest :)

  7. #27
    Hi Mark
    The little sketch doesn't specify a hex head and as someone had mentioned just slotting it i assumed 20.5 Dia not A/F(my bad).
    1.75mm & 1.25mm refer to the pitch, the effective diameter has to be within a given tolerance for the type of fit required or the thread with either be too slack a fit or will not fit its matting component.
    There's a little sketch in the ZEUS handbook that will explain.
    I wasn't trying to be clever, i was just interested how an accurate thread could be produced with limited equipment, with a CNC lathe it shouldn't be a problem.
    I would consider a ring gauge to be a proper gauge also the thread parallels, these are required to find the effective dia, in the case of the ring gauge you have a go-no go situation, if it fits and isn't a loose fit it's acceptable,with the parallels you do get a definitive size. just want to be clear that i have zero knowledge of CNC turning/milling ect
    Regards

  8. #28
    OK I'm with you, to be honest I am not so keen on the job either, I was thinking thread milling them was the way to go, two tool changes+slit saw, it would mean more waste (for work holding) but the hex head would be nice n simple
    I would see how far from the 12mm the sample was and speak to the customer if there was anything wild going on.
    I am sure with a thread mill you could sneak your way in till you hit the sweet spot then run 12 off..... but Iv never cut Peek....

    I get the feeling the issue is one of material over an uber precise M12

  9. For CNC you still need some form of gauge to check the size/fit.
    CNC has the advantage that it should be easier to get things on size, and then once things are set on size, they shouldn't change by much.

    From the original post, I'm assuming tolerance isn't that tight.

  10. #30
    Yes tolerance isn't that tight at all. They are only meant to be done up finger-tight. Hex head is not needed. However my friend said he has run out of money for now and will need to wait a few weeks.
    Last edited by Tenson; 17-06-2013 at 05:24 PM.

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