Seeking Advice on Milling Machine

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SL Ethel
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Re: Seeking Advice on Milling Machine

Post by SL Ethel » Wed Feb 14, 2018 5:18 pm

I'll double check the threads today. Everything else on the machine is metric, so I didn't think to try 1/4-20. I checked one of the original gib screws against M6 bolts (seemed to match for diameter) and M8-1.25 bolts (matched for pitch) at the hardware store, though not with a micrometer.

This machine has tapered gibs, with one screw at each end locating the gib. It seems like it would take a substantial load, but you are right that mild steel should probably work.

Thanks,
Scott
SL Ethel
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Re: Seeking Advice on Milling Machine

Post by SL Ethel » Wed Feb 14, 2018 7:10 pm

DetroiTug wrote:Quote: "And these screws are M6-1.25."

1.25 pitch lead equals .0492"

20 threads per inch equals .050" pitch lead.

6mm equals .236"

1/4" equals .250"

I think you have 1/4-20 there. Try a 1/4-20 bottoming tap in the hole.

-Ron
If there was an egg-on-my-face emogi, I think I'd have to use it now. Ron, I'm certain you are right - they're just 1/4-20. 1/4-20 fasteners fit perfectly. I've been chasing around like a fool after an imaginary fastener spec when what I needed was the most common possible size. I have 1/4" threaded rod by the yard in my shop, 1/4" nuts in multiple hardness grades etc. And I totally missed that. Thank you, Ron.

And now back to my regularly scheduled bumbling...

Cheers,
Scott
Mike Rometer
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Re: Seeking Advice on Milling Machine

Post by Mike Rometer » Thu Feb 15, 2018 12:56 pm

DetroiTug wrote:Quote: "And these screws are M6-1.25."

1.25 pitch lead equals .0492"

20 threads per inch equals .050" pitch lead.

6mm equals .236"

1/4" equals .250"

I think you have 1/4-20 there. Try a 1/4-20 bottoming tap in the hole.

-Ron
As I suggested the real question is whether it's Whit or UNC. When these machines were cloned, they cloned EVERYTHING and stuck with Imperial measure 'til they learned to change it to metric, when they then changed the designs to suit themselves. If you copy something do it exactly then you know it'll work.
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DetroiTug
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Re: Seeking Advice on Milling Machine

Post by DetroiTug » Thu Feb 15, 2018 4:21 pm

Scott, If I had a Nickle for every time I did something similar, I'd have several nickles. :)

50 years ago we were told in grade school "The metric system is coming, better prepare yourself!" No one could have prepared themselves for the amount of cost and confusion it has caused. I have no quibble with the Metric system and I wish we had switched over instead of this never-ending limbo we've been in, it is much easier to understand, the pitch lead for fasteners is better in regard to tap breakage, run a 10-24 tap any length of time and you'll know what I mean. When I did automotive tooling, all of the prints were in Metric, and most of our machines used English dials (and the brand new machines still do), all of the stock coming in was in nominal English increments. So, we worked in English, which meant every drawing coming in had to be converted to English measurements. Just about every machinist or fabricator doing that type of work was having to do the same thing, now imagine the cost in lost time it incurred and the mistakes it caused resulting in spoiled material. It's been very costly.

Anywho, glad you got your mill in place. Time to make some stuff! :)

Mike, Yeah you called it. My experience is tooling etc coming out of Asia, they have no standard, it might be Metric or English. I think what it is, some of it is copying an existing design right down to fastener sizes and some of it is, their planned target market, American or European.

-Ron
SL Ethel
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Re: Seeking Advice on Milling Machine

Post by SL Ethel » Thu Feb 15, 2018 6:46 pm

Mike, thanks for the reminder to check the thread form. 1/4-20 threaded rod felt right threading into the machine, but I don't know if whitworth might also fit. I'll double check. I have most of the original gib screws, so I should be able to be sure fairly easily.

Thanks!

Scott
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