ajmac Posted July 2, 2010 Share Posted July 2, 2010 Post War into the 1960s (started to go Metric in the mid 70s) the British motor industry moved over to UNF (General) and UNC (for aluminium casting etc) threads, I know.. I believe both these types originated or perhaps accelerated in use during WW2 due to the USAs huge production volumes. When restoring a wartime British vehicle is there any chance of UNC or UNF being utilised or is all the larger fastening going to be done with Whitworth threads? I know the obvious answer is to check on the vehicle.... but what if that isn't possible. Would the manuals have gone into the detail of thread type etc? Quote Link to comment Share on other sites More sharing options...
fv1609 Posted July 2, 2010 Share Posted July 2, 2010 The parts list/catalogue may define the thread. The relevant VAOS (Vocabulary of Army Ordnance Stores) might indicate this or it could be determined from the manufacturer's part number which is often inherent in the VAOS item number. Most fixings & fasteners would not be exclusively MT & would be in VAOS G1 Parts 1, 2 & 3. Although general MT stores not specific to one vehicle type would be in VAOS LV6. Quote Link to comment Share on other sites More sharing options...
Adrian Barrell Posted July 2, 2010 Share Posted July 2, 2010 Nice try Alastair but you're probably going to need BSF I'm afraid! :-D Not sure about the engines though, I suppose they could have been ANF and ANC due to their origins. UNF did not exist during the war, the sizes only becoming 'unified' in the 1950s I think. In general, the standard ANF and ANC pitches were adopted as the unified sizes but not all. As an example, the favoured ANF for 1" was 14 tpi, unified settling for 12 tpi. That can cause problems as there is a lot of 1" in Shermans..... Quote Link to comment Share on other sites More sharing options...
ajmac Posted July 2, 2010 Author Share Posted July 2, 2010 Nuts! Quote Link to comment Share on other sites More sharing options...
woa2 Posted July 2, 2010 Share Posted July 2, 2010 On a British Wartime Ford V8, the threads are UNC on anything produced by Ford (such as the engine and transmission), but the body is held together by Whitworth bolts and BA screws as it was produced by BMB a British company. It's a nightmare finding the right spanner sometimes..... Quote Link to comment Share on other sites More sharing options...
Stormin Posted July 2, 2010 Share Posted July 2, 2010 Nice try but Mr Whitworth was the pioneer who came up with the standard threads before metric came along. The Amercians just copied them with their ANC/ANF which later became UNC/UNF. Only changing the pitch of 1/2" by one thread per inch to differentiate. Most UNC are interchangeable with BSW (apart from 1/2") same for UNF and BSF I think. I think they copied their tapered pipe thread off ours as well with only slight variations. Quote Link to comment Share on other sites More sharing options...
Adrian Barrell Posted July 2, 2010 Share Posted July 2, 2010 British and American thread forms are different angles and unlike BSW/UNC (apart from the 1/2"), BSF and UNF are different pitches on all sizes. Quote Link to comment Share on other sites More sharing options...
antarmike Posted July 2, 2010 Share Posted July 2, 2010 (edited) On a British Wartime Ford V8, the threads are UNC on anything produced by Ford (such as the engine and transmission), but the body is held together by Whitworth bolts and BA screws as it was produced by BMB a British company. It's a nightmare finding the right spanner sometimes..... Wartime Fords V8 could not have had UNC (or UNF) since the system was not yet available Problems with lack of interchangeability among American, Canadian, and British parts during World War II led to an effort to unify the inch-based standards among these closely allied nations, and the Unified Thread Standard was adopted by the Screw Thread Standardization Committees of Canada, the United Kingdom, and the United States on November 18, 1949 in Washington, D.C., with the hope that they would be adopted universally. (The original UTS standard may be found in ASA (now ANSI) publication, Vol. 1, 1949.) UTS consists of Unified Coarse (UNC), Unified Fine (UNF), Unified Extra Fine (UNEF) and Unified Special (UNS). The standard was not widely taken up in the UK. This homes in on the exact date that Unified system came into existance. ( previoiusly mentioned by Adrian as circa 1950's). So Adrian is quite right that wartime American threads would have probably been A.N.C. or A.N.F. Nice try Alastair but you're probably going to need BSF I'm afraid! :-D Not sure about the engines though, I suppose they could have been ANF and ANC due to their origins. UNF did not exist during the war, the sizes only becoming 'unified' in the 1950s I think. In general, the standard ANF and ANC pitches were adopted as the unified sizes but not all. As an example, the favoured ANF for 1" was 14 tpi, unified settling for 12 tpi. That can cause problems as there is a lot of 1" in Shermans..... Edited July 2, 2010 by antarmike Quote Link to comment Share on other sites More sharing options...
Tony B Posted July 2, 2010 Share Posted July 2, 2010 Nice try but Mr Whitworth was the pioneer who came up with the standard threads before metric came along.The Amercians just copied them with their ANC/ANF which later became UNC/UNF. Only changing the pitch of 1/2" by one thread per inch to differentiate. Most UNC are interchangeable with BSW (apart from 1/2") same for UNF and BSF I think. I think they copied their tapered pipe thread off ours as well with only slight variations. Britsh pipe threads fit the top of a Dodge master cylinder, thnkfully. Makes for an easy fitting for a pressure bleder. Quote Link to comment Share on other sites More sharing options...
Adrian Barrell Posted July 3, 2010 Share Posted July 3, 2010 Britsh pipe threads fit the top of a Dodge master cylinder, thnkfully. Makes for an easy fitting for a pressure bleder. Again, some sizes of BSP and NPT are the same pitch but they are not interchangeable as such, there being differences in thread form and shape. Most sizes are one different in pitch. Quote Link to comment Share on other sites More sharing options...
Jiver Posted July 3, 2010 Share Posted July 3, 2010 I've got a box full of ANC taps of various sizes which are similar to unc but pitch angle is slightly diferent. Are they any use to any body? Quote Link to comment Share on other sites More sharing options...
protruck Posted July 3, 2010 Share Posted July 3, 2010 Send ajmac a PM. he maybe interested for the Loyd carrier he has. Clive Quote Link to comment Share on other sites More sharing options...
tim gray Posted July 6, 2010 Share Posted July 6, 2010 Re various thread forms etc, If anyone is interested PM me and i can send a schedule of threads and tap sizes for a range of types that the school uses to teach the fitters etc . They are in PDF format so if someone can advise if the forum can support and show a pdf file i will upload them and you can down load at your leasure, may be usfull for those who are new into the vehicle scene etc. Regards Tim Quote Link to comment Share on other sites More sharing options...
abn deuce Posted July 6, 2010 Share Posted July 6, 2010 Something that should have a sticky and or put in a Forum folder Quote Link to comment Share on other sites More sharing options...
tim gray Posted July 6, 2010 Share Posted July 6, 2010 Something that should have a sticky and or put in a Forum folder I will try to post the first PDF as a test to see how it comes up, multiple PDF,s as the kit at work will only do a certain size, it used to be able to do JPEGS which would have been better for us but the IT guru,s decided to lock every thing up :-( Screw Threads 1and 2.PDF Quote Link to comment Share on other sites More sharing options...
tim gray Posted July 6, 2010 Share Posted July 6, 2010 Last post seemed to work so will post the rest, opened fine on my machine as long as you have a PDF reader, If any of you splendidly capable IT users out thier can convert to a JPEG image fill your boots as it may provide access to a wider audience. Regards Tim Screw Threads 7 and 8.PDF Screw Threads 5 and 6.PDF Screw Threads 3 and 4.PDF Screw Threads 9.PDF Quote Link to comment Share on other sites More sharing options...
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