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Pfrey
Tinkerer
Username: Pfrey
Post Number: 1
Registered: 08-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 05, 2008 - 10:47 am: | 
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Hi, One of the screws holding the focusing ring to the helical ring on my Peckham Wray 4x5 aerial /press camera is missing..Does anyone know what standard Wray used for the screws? Metric, SAE or BA? I took the screw to the local Fastenal, but their plastic index is worn and didn't really give me confidence...one size screw seem to fit an SAE index, and the other seemed metric..possible during the short WWII production, but I kind of doubt it. There's a place called British Fasteners that I can send a sample to, but before I went to the trouble, I figured I'd ask this forum. thanks |
Glenn
Tinkerer
Username: Glenn
Post Number: 389
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 05, 2008 - 07:29 pm: |
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Depends on the diameter of the screw in question. Small diameters will be BA, larger ones could be BSF. There was a British Standard produced during WW11 that rationalised screw/thread sizes, in order to simplify supply. Many instrument makers followed this standard - not much choice really as only limited ranges produced. So unless Wray made their own fasteners or had large stocks, I guess it most likely will be BA - which as you will probably know is a metric pitch series. Hence your metric observation? |
Pfrey
Tinkerer
Username: Pfrey
Post Number: 3
Registered: 08-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 06, 2008 - 08:56 am: |
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Thanks for the info Glenn. I guess I'll just send it off and see what the British Fastener guy says. thanks |
Glenn
Tinkerer
Username: Glenn
Post Number: 390
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 06, 2008 - 10:26 am: |
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Peter,
If you can accurately measure the diameter - in both imperial and metric - I can send you some samples of BA and BSF screws. By accurate I mean to two decimal places, using a vernier caliper or micrometer. If we assume it is BA, a ball park figure for the diameter in inch or mm would allow me to send you the correct BA size and the size above and below - just to ensure you are covered. I have various head forms, but you may have to reduce the length. Feel free to email me directly. |
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