onetrack Posted October 9, 2020 Posted October 9, 2020 (edited) AF stands for "Across (the) Flats" - the measurement from one flat face on the bolt head or nut, to the opposite parallel flat face. Used to work in with another earthmoving contractor bloke name Austin (Aussie) Fulford. When we were doing repair work on the dozers (we would often work our machines together on the same job), and we were finishing up and gathering up our respective tools - sometimes there'd be a little residual doubt over ownership of a particular spanner. Aussie would always cheerfully claim any tool with AF on it, as his - because his initials were stamped on it! Edited October 9, 2020 by onetrack 1
old man emu Posted October 9, 2020 Posted October 9, 2020 58 minutes ago, Bruce Tuncks said: OME, does it mean Automotive Fine? Nope. Onetrack got it. 1
pmccarthy Posted October 9, 2020 Posted October 9, 2020 3 hours ago, Bruce Tuncks said: There is a letter from James Watt about how this wonderful new cylinder was only 3/8 inch wider in one diameter than another. I guess that this is why they invented piston rings. I think those first steam engines used greasy hemp packing. 1
pmccarthy Posted October 9, 2020 Posted October 9, 2020 I have recently discovered the great advantage of the old Imperial system. When you are trying to reproduce old and damaged parts, it can be impossible to know what the original dimension was in millimetres. But in inches it is obvious. This was a one-inch board, or the rebate was 7/8 inch deep.
spacesailor Posted October 9, 2020 Posted October 9, 2020 AND .you can measure without a dedicated tape-measure! !. spacesailor
old man emu Posted October 10, 2020 Posted October 10, 2020 3 hours ago, pmccarthy said: When you are trying to reproduce old and damaged parts, it can be impossible to know what the original dimension was in millimetres Obviously when working with things made pre-metrification, you have to work in the units of the day. I've just got a heap of my Dad's old spanners and I see that there are Whitworth ones amongst them. Whitworth and BSF spanner markings refer to the bolt diameter, rather than the distance across the flats of the hexagon (A/F) as in other standards. Whitworth is still used. The standard tripod mount on all SLR cameras and, where fitted, on compact cameras, and therefore on all tripods and monopods, is 1/4 Inch Whitworth. Larger format cameras use 5/16 inch Whitworth with tripod adaptors from 1/4 inch Whitworth if necessary. Fixings for garden gates traditionally used Whitworth carriage bolts, and these are still the standard supplied in UK and Australia. The 5⁄32 in Whitworth threads have been the standard Meccano thread for many years and it is still the thread in use by the French Meccano Company. https://en.wikipedia.org/wiki/British_Standard_Whitworth
pmccarthy Posted October 10, 2020 Posted October 10, 2020 I think the best grounding in mechanical skills is a few years building Meccano when you are quite young. 2 1
Yenn Posted October 10, 2020 Posted October 10, 2020 (edited) Witworth is interchangeable with UNC, unified national coarse thread. I think the only difference is that the whit threads are 60 deg sides and the UNC are 55 degrees. The yanks are not only mad to be using fraction sizes, but they also have bolt sizes in numbers. No 0 is .060" and each increase of number is an extra .013' in diameter. Still in common use in aircraft. Edited October 10, 2020 by Yenn Extra
spacesailor Posted October 10, 2020 Posted October 10, 2020 Yenn Do the number drills have a correlation to those number bolt sizes ?. If it does , it could have been a game changer. spacesailor
old man emu Posted October 10, 2020 Posted October 10, 2020 Number and letter sizes are commonly used for twist drill bits rather than other drill forms, as the range covers the common sizes from 1/16", increasing by 1/64". Number drill bit gauge sizes range from size 80 (the smallest) to size 1 (the largest) followed by letter gauge size A (the smallest) to size Z (the largest). The gauge-to-diameter ratio is not defined by a formula, but is instead based on, but is not identical to, the Stubs Steel Wire Gauge, which originated in Britain during the 19th century. Although the ASME B94.11M twist drill standard, for example, lists sizes as small as size 97, sizes smaller than 80 are rarely encountered in practice. When a number is used to describe a size, the larger the number, the smaller the diameter. The two sizes commonly found in aircraft maintenance are #40 and #30, which are the sizes of drills used for making the holes that nutplate rivets, as well as #21 and #11 and "F" for solid rivets, and also #27, #20, #16, #10, # 5 and "I" for Cherymax rivets. You should always consult the specifications for a rivet before drilling holes as the amount of slop in the hole determines the quality of the grip of the rivet. Needless to say, you shouldn't use drills from a set of common sizes (1/16 to 1/2") when drilling holes for rivets. Another place that numbered drills are used is in carburettors to clear the galleries associated with the fuel jets. But let's not consider playing with those. The worst thing about numbered drills is trying to put them back in their correct order if you drop the box. 2 1
facthunter Posted November 7, 2020 Posted November 7, 2020 it's when your DAYS are numbered you have to think outside of the square or at least tidy a few things up.. Nev
Bruce Tuncks Posted November 14, 2020 Posted November 14, 2020 Three score years and ten shalt be thy days.... bugger, I'm well past that.
willedoo Posted December 6, 2020 Posted December 6, 2020 Arrgh! Today is Pirate Appreciation Day on the Pastafarian calendar. 1
Marty_d Posted December 7, 2020 Posted December 7, 2020 Isn't it funny, the Pastafarians say "May you be touched by his noodly appendage", where the Catholic altar boys are hoping like hell they aren't! 1 1
old man emu Posted January 1, 2021 Posted January 1, 2021 Getting back to the Special Creation -v- Evolution discussion, I wonder what members of the other branches of the Abrahamic tradition say about it. I feel that the debate is only between European Christians, especially the Protestant Fundamentalists and more so especially the American Protestant Fundamentalists. Is the rest of the world who practise a monotheistic religion happy to accept that it doesn't matter how Life got to where it is, as long as you attribute to God the role of instigator of the process? 1
Bruce Tuncks Posted January 1, 2021 Posted January 1, 2021 Gosh OME, there is a very close correlation between accepting evolution and treating your women well. I am sure that is not coincidental. I really like how you refer to "branches of the Abrahamic religion". It is scientifically correct...Would you get killed for blasphemy saying that in ISIS territory?
old man emu Posted January 1, 2021 Posted January 1, 2021 29 minutes ago, Bruce Tuncks said: there is a very close correlation between accepting evolution and treating your women well. Call an ambulance! Bruce has caught the Trump virus! That, my friend, is what is called a logical non-sequitur, as in "Dogs have tails. Horses have tails. Therefore a horse is a dog."
Marty_d Posted January 2, 2021 Posted January 2, 2021 6 hours ago, old man emu said: Call an ambulance! Bruce has caught the Trump virus! That, my friend, is what is called a logical non-sequitur, as in "Dogs have tails. Horses have tails. Therefore a horse is a dog." Not really. More education (of non-religious kind) = better acceptance of science including evolutionary theory. More education also = fairer treatment of women. So Bruce's statement is not really a non-sequitur, there is a relationship there. 1
Bruce Tuncks Posted January 12, 2021 Posted January 12, 2021 I had a fantasy on seeing a video of an ISIS court on a flat roof 3 story building. They were trying suspected homosexuals and throwing them off the roof on being found guilty. My fantasy was being superman and going there and throwing the judges and soldiers off the roof.
Marty_d Posted January 12, 2021 Posted January 12, 2021 My fantasy involves being irresistible to women, but I've got about as much chance of that as you have of flying without your aircraft Bruce! 1
Jerry_Atrick Posted January 14, 2021 Posted January 14, 2021 By implication, doesn’t a fantasy of being Superman include being irresistible to women?
Marty_d Posted January 14, 2021 Posted January 14, 2021 2 hours ago, Jerry_Atrick said: By implication, doesn’t a fantasy of being Superman include being irresistible to women? There's a problem with that, described in the aptly named short story "Man of Steel, woman of Tissue Paper".
Jerry_Atrick Posted January 14, 2021 Posted January 14, 2021 55 minutes ago, Marty_d said: There's a problem with that, described in the aptly named short story "Man of Steel, woman of Tissue Paper". Heated steel can be quite malleable...
Marty_d Posted January 14, 2021 Posted January 14, 2021 Hmm, red hot molten steel - not sure that would be any less painful for the woman of tissue paper!
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