gauges and drill numbers????

[havoc]

Has anyone here a list converting plate and wire gauges and drill numbers and letters to metric sizes? I now have a few LBSC plans and would like to make a choice in it and then convert to metric. But when I look for that info I find most references in the US and I don't trust that these are the same than the UK ones. Not even sure they are the same now than when LBSC wrote the articles...

[paul]

www.csgnetwork.com/drillsizeconvert.html

[alanstepney]

Try:
www.alanstepney.info/page8.html

for drill sizes and thread sizes.

[havoc]

Thanks for those tables. Now I only need one for the plate gauges. I fear it will be a rather serious redesign...

Alan, I looked through the table on your page and I much appriciate the BA<>metric list. But there is one thing I don't understand: you put in your table for metric threads those I would expect to be at the ME threads and vice-versa. Like for 6mm, in the metric table is 6x0.5 and 6x0.75, both are metric fine threads and 6x0.5 is often used in model engineering work. The standard M6x1 is in the model engineering table.

[freddo]

This what you're after Havoc:

www.vhfman.freeuk.com/tables/swg.html

Freddo

[havoc]

Is the plate gauge the same as the wire gauge? Sorry, but imperial is a closed book to me.

[freddo]

havoc said:

Is the plate gauge the same as the wire gauge? Sorry, but imperial is a closed book to me.

Have a look at this page and scroll down a bit and you will see you are far from alone with the confusion:-

www.answers.com/topic/gauge


SWG = Standard Wire Gauge, UK official in 1883, standard in 1893 (Imperial Wire Gauge, British Standard Wire Gauge);
BWG = Birmingham Wire Gauge (Stubbs Iron Wire Gauge) of 1884;
(British) Stubbs Steel Wire Gauge (continues to gauge 80 for 0.013 in);
US Steel Wire Gage (Roebling Wire Gage, Brown and Moen Wire Gage, American Steel and Wire Gage);
AWG = American Wire Gage, from the Brown and Sharp of the 1850s;
W. & M. Music Wire Gage (USA);
US Standard Steel Plate Gage, authorized in 1893;
U.S. Manufacturers' Steel Sheet Gage;
BG = Birmingham Gauge for steel sheet, from 1884.Modern practice is to use direct measures of thickness, based on the R10" series of preferred numbers expressed in millimetres.ANSI/ASME B32.3M 1984

Then there's a table of differences.

Freddo

[cotswold]

havoc said:

... I now have a few LBSC plans and would like to make a choice in it and then convert to metric. ...

May I respectfully suggest that you consider very carefully before converting BA screw sizes. As you probably already know, 0BA is a coarse thread with 6mm diameter and 1mm pitch. Thereafter The BA series progress by a factor of 0.9 (rounded). Thus giving a smooth range down to 1mm x 0.23mm (14BA) or even smaller. BA screws and screwing tackle are widely available from the UK modelling trade and postage costs are not likely to be prohibitively high.

Good luck with your project.

[havoc]

Thanks for all the tables, I think I now have what I need.

As for the BA screws I prefer to go "hard" metric. Far easier to have only a single type of screws, taps and dies than multiple systems. And the differences are not that large according to Alen's tables.