I adjusted the height of my Hadcock 242 silver arm today. I noticed the correct size 1/16" allen key felt loose in the socket of the grub screw in the base. does anyone know the size & thread of the grub screw George used please. as I wish to replace it, being Imperial could be several ie UNF UNC BSF or even BA.
Hi, it would not be UNC or F as no self respecting Englishman would use that thread range. However is could be metric.
Go to your local machine shop & ask to try several know small machine screws in the threaded base hole.
Cheers
Go to your local machine shop & ask to try several know small machine screws in the threaded base hole.
Cheers
1/16" = 1.58 mm
1.6 mm may be the correct size, Metric.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjTot_IxeP5AhWQ4XMBHcIIDV8QFnoECCAQAQ&url=https://en.wikipedia.org/wiki/Hex_key&usg=AOvVaw2zYjuFsvw4sdHdKpXkVCeo
Or you can measure across flats with Vernier calipers, and work it out from that.
'George'?
If custom made, you may have some work to do, I knew somebody who bought taps in scrap, so his work had us using both Imperial and Metric wrenches...said new taps were too expensive!
1.6 mm may be the correct size, Metric.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjTot_IxeP5AhWQ4XMBHcIIDV8QFnoECCAQAQ&url=https://en.wikipedia.org/wiki/Hex_key&usg=AOvVaw2zYjuFsvw4sdHdKpXkVCeo
Or you can measure across flats with Vernier calipers, and work it out from that.
'George'?
If custom made, you may have some work to do, I knew somebody who bought taps in scrap, so his work had us using both Imperial and Metric wrenches...said new taps were too expensive!
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Thank you gents 1/16" allen key is the correct size & was included in the box with the arm. London used to have a couple of specialist screw/fastener companies none within 45k of my HA now. It was suggested on another forum it may be 4BA after someone took their grub screw out, it is definitely not metric. "George" was George Hadcock who designed the original arm & held the patent on the 4 ball bearing pivot point, my friend Len Gregory (deceased) AKA The Cartridgeman helped with the 242 arm.
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