imperial/decimal/metric

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Hi all.Wondering if anyone could give me a list of the imperial system from 1/2 inch through to 1 inch. I have a converter so I dont need the metric system. I used a drill bit holder for the first half, but it only goes to 1/2 inch. Would be great if anyone knows the decimals for these as well.Im using an old drawing at work at the moment and Im not used to working with imperial. Any help would be really appreciated.Thanx
Reply:Originally Posted by juiceHi all.Wondering if anyone could give me a list of the imperial system from 1/2 inch through to 1 inch. I have a converter so I dont need the metric system. I used a drill bit holder for the first half, but it only goes to 1/2 inch. Would be great if anyone knows the decimals for these as well.Im using an old drawing at work at the moment and Im not used to working with imperial. Any help would be really appreciated.Thanx
Reply:Hey Clive,Thanx mate. Just one question? ( shows how much I kknow about the imperial system) Is it 63/64 then 1 inch?? Sorry, I just have never used that system.It really makes it hard to understand a lot of the threads in this forum as well.  No offence to anyone!!!There is just no use of imperial in oz unless you get old drawings like I did, or you are talking to people that used it, or used it and converted. I was too young to learn it. Metric man me
Reply:Originally Posted by juiceHey Clive,Thanx mate. Just one question? ( shows how much I kknow about the imperial system) Is it 63/64 then 1 inch?? Sorry, I just have never used that system.It really makes it hard to understand a lot of the threads in this forum as well.  No offence to anyone!!!There is just no use of imperial in oz unless you get old drawings like I did, or you are talking to people that used it, or used it and converted. I was too young to learn it. Metric man me
Reply:Mainly all we see at work is imperial in say one hole at 1 1/16 and say another  1 16/32. Then I have to find the centre to centre measurement. Its mainly on three point linkage set ups, whick do have a bit of play in them, but I really like to be precise!!And as you would know, a steel rule or tape are never that accurate at measuring a hole that has been drilled imperial to measure in metric. Maybee I just need to learn the imperial system as well.Thanx for your help Clive
Reply:The main reason I wanted to know about the 1/2 inch to 1 inch is that I have a small exersize book that Im writing down the conversions in for future referance.I think it may be a helpful thing to have. If I could take my pc with me I would be better off, but I dont think it would appreciate the metal dust. lol
Reply:Google is your friend...lookup drill bit charts.  This is the first hit I chose.http://www.saw-online.com/Tips/drill.htmUse a chart!  I have seen countless screw ups with holes drilled or punched the incorrect size simply because someone guess the inch or metric equivalent.
Reply:Juice,If you are converting imperial to metric from a fraction first find the decimal. ie 63/64, 63 divided by 64 = .984375 so .984 is close enough. then multiply by 25.4 =24.99mm, call it 25.The imperial system is simple enough first the inch is divided by 2 =1/2.Then that is divided by 2 again= 1/4 and so on. General workshop practice you wont measure 1/64 with rule or tape, that is why we have clearance holes to allow for slight differences where a hole has been centre punched and it is slightly off, drill sharpened incorrectly so same again and so on.If you are measuring say a pcd on a flange and find it is say 146mm. That is not a basic metric size which are usually in 5mm increments, not always tho'. So divide it by 25.4 you will get 5.748" which is 2 thou less than 5 3/4 so that is obviously an imperial conversion. When we went metric a lot of things stayed the same but the sizes were given in metric. A classic is welding rods.Unlike the USA we always classified by gauge (Birmingham wire gauge) so our basics were 12 gauge, 10 gauge, 8 and 6 these became 12g=2.6mm. 10g =3.15mm 8g =4mm, 6g =5mmNearly the same with bolts, we went 1/4 to 6mm 5/16 to 8mm. 3/8 to 10mm. 1/2 to 12mm, 5/8 to 16mm, which are not exact conversions. I am fairly certain we went to these sizes as approximations that would fit existing holes rather than following the French or German system. So for example if you had a bit of plant that was held together by 5/8 bolts you would be able to bang a 16 in the same hole no trouble. And after changover we had machinery that we worked on and a couple of bolts would get gassed off because they were tight so they would be replaced with metric and you ended up with both on the same machine. I used to carry a spanner that fitted 5/8 BSW and I filed out the hex on the other end to fit the 16mm nut. With your hole centres, for the same sized holes go from edge of one hole to the same edge on the next that gives you dead centre.Clive
Reply:Thanks clive. Thats a naet trick to work out the decimal ant then multiply it by 25.4. I love to learn tricks like that!!!