Safe Speed Forums

Pne for the more elderly ( or perhaps some chippy types ). Years ago I was told how to size an imperial screw by measuring the head . I seem to remember it was to measure the head in 1/8" and then there was some juggleing . Any one remember how it was done ?. Not essential ,just bothering me that I can't remember that one .Mind you it was over 50 years ago .

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

What sort of screw? Woodscrews? The typical old sort of "pan head" ones?

YES ,thanks mate,pan/cheese & countersunk for wood. I found most places oly quote in mm, and getting hold of panheads in silver was almost impossible in amy small quantity. I did find one place selling about ten in a pack -almost £3.Then I looked at screwfix on line- 200 6x1" @£2 a box - job done. More than I'll ever use. Still trying to remember th formula though .

_________________
lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Glad you're sorted. This might help, but I don't know that the American numbering system was the same as the old British one.

http://www.jamestowndistributors.com/us ... rew+Sizing

I THINK it was (at least as far as shank diameter was concerned), but not sure about the pitch of the threads.

I found this one, but still intregued to remember .The method I knew involved measuring the head in 1/8 inch , subtracting a figure and multiplying by another

Found this ,which is similar

_________________
lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Ah yes, that sounds like the imperial system at it's best!

I prefer the metric system:

1. Place the shank of the screw between the jaws of calipers that can measure to half a millimetre. Adjust the calipers to read the diameter in millimetres, expressed to the nearest half a millimetre.

2. That's the size of screw you want!

I mean, WHY oh WHY did we ever persist with that system?! Did our forefathers have 12 fingers? Did they think "Oh, we've had 12 of those units now. Let's go for a different number in the next column".

"Ok, how about 8"?

"nah, we've already used 8. 8 of the small things make one big thing, and 12 of the big things make a bigger thing. How about three of the bigger things making a yard"?

"Great idea, then we can have 220 of those in a furlong, and go back to 8 of those making a mile"...

ah the number of times i've bought a box of 100 or 200 saying that's more than i'll ever need.... only to be back the next week for another box

I agree ,Ed- I've done that, but it's been csk ones, not cheese heads . I did get two boxes of drywall ones ( 1" & 2" not so long ago ,but these csk ones are so great for most jobs. Sharp point, so no need for a pilot), that are great on most materials wher you can hide a black head. I've still got the remains of a box of 8x2.5" I "rescued" from my kit when working for a firm over ten years ago . Not often I can find a use for them,but I've used a lot of csk ones in that time .

_________________
lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on