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No Longer Active
09-19-2011, 11:48 AM
Hi All,

I have embarked on a project where all the measurements are 'imperial' which is what is used in the US etc, but being from the UK I need to buy in 'Metric'.

How or where can I find information on converting imperial hardware to metric.

In the UK, we just don't use inches as its all MM, and inches is confusing the **** out of me.

Or, I wished there were a site where I can buy all my hardware in imperial and just get it all shipped to me in one go without the headache of converting a 5/16-18 nut into a metric one, and something that a british guy will understand.

Can anyone help me?

blueskydriver
09-19-2011, 12:04 PM
Alex, just use a "inches to mm" converter on the Internet...like this one:

http://www.convertunits.com/from/mm/to/inches

As far as tools, us US folks feel the same about metric; therefore, you have to buy and learn to use both measurements. If you don't have two sets of tools (imperial and metric), then you need to invest now. As for the conversion, you could print out a conversion chart like this:

http://mdmetric.com/tech/cvtcht.htm

Hopefully, you'll soon feel better about the measurement systems. We used to hate using metric, but truthfully, it is amazingly easy to understand and use. What could be more simpler than divisions of 10?

BSD Team

No Longer Active
09-19-2011, 12:09 PM
Hi.

But, as for a 5/16-18 what is that. ok 5/16 equals 12.7mm, but a 12.7mm nut doesnt exist in the uk. What does the '-18' at the end of 5/16's mean.

Maybe I sound thick but metric is all 1's, 10s' and 100's etc, its very easy as for working in eighths, sixteenths etc.

Alex

fordgt40
09-19-2011, 12:31 PM
Alex

I do not know your project. Unless it is a highly stressed piece of fabrication, I doubt that it requires exact metric equivalents in terms of size, stress capacity, thread sizes, on bolts etc. I would just take the nearest metric size that suits/looks ok and/or fits the hole :)

BTW 5/16 does not equal 12.7mm, it should be 7.9mm. As 1 inch = 25.4mm then 1/16 of an inch = 25.4/16 = 1.5875mm. Therefore 5/16 of an inch = 5 x 1.5875 = 7.937mm

I am old enough to have had to learn both systems

Good luck

David

smendlik
09-19-2011, 01:14 PM
Hi.

But, as for a 5/16-18 what is that. ok 5/16 equals 12.7mm, but a 12.7mm nut doesnt exist in the uk. What does the '-18' at the end of 5/16's mean.

Maybe I sound thick but metric is all 1's, 10s' and 100's etc, its very easy as for working in eighths, sixteenths etc.

Alex

The -18 means there are 18 threads per inch. If you were to rotate the the bolt/nut 18 full turns it will travel 1 full inch. As with metric threads we there are fine and coarse threads for each nominal bolt size, depending on your needs.

Ronson2k9
09-19-2011, 01:27 PM
Alex.. I use the DAS Unit Converter (http://das-uc.110mb.com/) all the time for making conversions. It converts nearly everything. I use it for quite a bit of stuff. Also all you need do is type in (for example) 2 inches in cm (http://www.google.ca/search?btnG=Google+Search&q=2+inches+in+CM#sclient=psy-ab&hl=en&safe=off&biw=1181&bih=751&source=hp&q=2%20inches%20in%20cm&tbs=search%3FbtnG%3DGoogle%2BSearch&lr=&as_filetype=&pbx=1&oq=2%20inches%20in%20&aq=2&aqi=g4&aql=&gs_sm=sc&gs_upl=0l0l2l610l0l0l0l0l0l0l0l0ll0l0&bav=on.2,or.r_gc.r_pw.&fp=df36a59dfc595e91&pf=p&pdl=300) into google search and google will do it for you.

I like the DAS converter though because you can just update the one and it will do the other without having to retype everything

No Longer Active
09-19-2011, 01:56 PM
Hi All,

Thanks for all your help so far, my head is hurting having been at work all day and now number crunching again lol!

Who can tell me what is the UK equivalent of:

1) #8-32 screw
2) #8 or #10 washers
3) #10-24 screw
4) #6 screw
5) #4 hose clamp

if i know what the above is called in the uk, then i think i can work out the rest!


many many many thanks!

Ronson2k9
09-19-2011, 06:49 PM
Now there is the Metric and Imperial version of these screws. They should come in both types in the UK as they do in Canada and we are officially metric as well.

However there is The Metric to Imperial Screw size conversion chart (http://www.thesitebox.com/Page/21/Metric-to-Imperial-Screw-Size-Conversion.aspx). Here is a UK based hardware store with Imperial screw sized screws Builder Depot (http://www.builderdepot.co.uk/tools-fixings/screws.html)

There is also a difference from Self Tapping to Machine screws as well.

I do hope that helps though.
Ron

cscotthendry
09-20-2011, 01:58 AM
Hi.

But, as for a 5/16-18 what is that. ok 5/16 equals 12.7mm, but a 12.7mm nut doesnt exist in the uk. What does the '-18' at the end of 5/16's mean.

Maybe I sound thick but metric is all 1's, 10s' and 100's etc, its very easy as for working in eighths, sixteenths etc.

Alex

Alex:

The -18 after the 5/16 is the number of threads per inch(TPI). Unfortunately when it comes to nuts and bolts, the two systems are totally incompatible in that you cannot put a metric nut on an imperial bolt no matter how close in size they are.

Without knowing what you're trying to do, the best advice is what a previous poster said; find a source for imperial nuts and bolts on the internet for those situations where you absolutely HAVE to have an imperial part and use metric stuff wherever else you can. Also, for the smaller, wire-size nuts and bolts such as #4-40, #6-32 etc, they can usually be sourced from local hobby stores.

BTW, 1 inch = 25.4mm This is good enough to do conversions between the two systems.

Meridian
09-20-2011, 09:30 AM
Alex,

The 8-32 and 10-24 are UNC screw threads used widely in the USA and Canada.
If you go onto e-bay(UK) and search 8-32 UNC you will find a selection of 8-32 UNC screws of all types, the same with 10-24.

All the best,

Andrew

No Longer Active
09-20-2011, 02:08 PM
Hi All,

Again thanks for the replies. Well I have got a few cnc plans, one being a small moving table machine and another slightly bigger. The small 10 x 9 cnc machines has nearly 5 times the parts than the bigger 13 x 13 machine. All parts lists are in imperial and both plans are designed so that all parts can be purchased from 'lowes' an american hardware store.

I am totally convinced that 'diy' is the way to go, especially for a first time machine. I have been researching cnc for a long time now after getting many of my parts made from cnc. I find cnczone my biggest inspiration for cnc at the moment.

Unfortunately, the UK lacks in any good plans and kits, although the 'good ones' are either very expensive in kit form or are just simply 'plans' and not 'how to's'. I have two excellent 'how to' cnc plans but they are just all in imperial. A metric list will be so much cheaper and easier for me to source parts.

Luckily my outlay so far covers only the cost for the plans, I hope to have 3 Nema23 steppers within a week, plus controller and power. I will use MACH3 to test.

Anyway I hope this clears up my reasons, and I will post updates soon....

Cheers.

Alex

blueskydriver
09-20-2011, 04:26 PM
Alex,

This is where the good old hardware store guy comes in, you go to the store with said metric bolt or screw and he helps you match it up to the Imperial one (on vice-versa). Although, if you do not have the said bolt or screw in hand you just need to have a conversion chart printed out.

Here is another way; do you know what a drillbit/bolt size checker is? It usually is a small plastic card that has holes and printed above the holes is sizes. One side of the card has Imperial and the other has Metric, so if you look at it you'll get the numbers you need; plus, it will help when you do have said bolt or screw in hand. You put it through hole and you now have the size of drill bit to use to make the same size hole. The Hardware store will have these cards.

Best Regards,

BSD

blueskydriver
09-21-2011, 10:31 AM
Looks like johny.7389 is a Bogus member. He has copied the post word for word and then added something that makes no sense...please check him out mods.

BSD

fordgt40
09-21-2011, 10:49 AM
BSD

Already reported, he has a few posts and has already caused confusion!!

David

JWS
09-21-2011, 02:28 PM
BSD

Already reported, he has a few posts and has already caused confusion!!

David

David,

did not receive a report notification. But came across the posts and acted upon your request.

Thanks anyway.

JWS

fordgt40
09-21-2011, 02:36 PM
JWS

May not have reported this post, but definitely did one of them - did not want to barrage you with duplicates :)

Thanks

David

JWS
09-21-2011, 03:22 PM
David,

let me rephrase, I did not receive any report notification. Strange.

JWS

fordgt40
09-21-2011, 03:27 PM
JWS

very strange indeed - I definitely pressed "report" wrote some text, and believed I had sent it.
Ah well, he was spotted anyway

David

JWS
09-21-2011, 03:53 PM
David,

be so kind to report this post so we can test if things are working properly.

JWS

fordgt40
09-21-2011, 04:04 PM
JWS

Done

David

JWS
09-21-2011, 04:24 PM
Hmmm .... no notification. I'll have to check this with Matt. Thanks.

JWS

blueskydriver
09-21-2011, 05:18 PM
JWS,

I reported it as well, so not sure why you're not getting the reports? I did type a note in the box also, so it sounds like a reporting feature is not working correctly...

Thank you for the great moderating work you do, without it, we'd have a 1000 BOGUS members to put up with!

Best Regards,

BSD

Westozy
09-21-2011, 07:10 PM
Hi guys, the reported posts are definately getting through to me.

I can't understand this type of behaviour, these people must have very sad lives!!

Cheers Gwyn

JWS
09-22-2011, 02:50 PM
JWS,

Thank you for the great moderating work you do, without it, we'd have a 1000 BOGUS members to put up with!

Best Regards,

BSD

You make me blush;-)

I informed Matt about it. Glad to hear Gwyn is getting them. I'm sure Matt will sort it out. So if there is no immediate (well in a day or two) response to a report, repeat it or send me a PM.

JWS

blueskydriver
09-22-2011, 03:17 PM
Okay, roger that...

BSD