Is there a downloadable chart for fine metric thread dimensions that is free?

WobblyHand

WobblyHand

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I've been able to find a chart for metric coarse threads that gives the major diameter and pitch diameters along with tolerances for 6g.
Is there a table or chart for fine metric threads with similar information? At the moment I am interested in sizes encompassing M2-M14. Not really excited about spending 118 swiss francs for each of the 2 or 3 ISO standards. I want enough info to single point metric fine threads that have some chance at interchangeability.

I have a screw app for my android phone, "UN Thread", which I am not sure I trust. (Data security, as opposed to whether the info is correct. I don't care to willy nilly install lots of apps as it is not clear to me how well they really are vetted.) I want to make a spreadsheet that has all the information in one place. And tells me how much more to cut. The screw app's interface is functional but a little clunky and doesn't support preloaded wire tables. Nor does it remember any of your previous settings, which is part of the clunkiness.

Anyone know if there's a fine metric thread chart M2-M14 that has max, min for Major diameter and Pitch diameter? Bonus if it's in csv or similar format. It's no fun manually typing lots of data, but I'll do it if necessary.
 
Yes! I was on that site, but somehow missed the table.

Only thing I can't figure out is how to copy the table... Can't cut and paste it, and it's not a downloadable image. It would be a lot of typing. Maybe I can view the source html and get it? It's worth a try!
 
On the subject of Fine vs. Coarse, there is only one "preferred" thread in the metric standards. There are numerous other acceptable threads (usually, but not always, finer than the preferred). On drawings, a call-out for the preferred thread will just be designated by the letter M and the diameter. For example, M8 (1.25 pitch), M10 (1.5) and M12 (1.75). All others will be designated by diameter and pitch (M8x1.00, M12x2.00).
A bolt designated M8x50 is 1.25 pitch and 50mm long.
 
From my reading, the only thing that was agreed upon by ISO were the coarse thread values. Every country had their preferred "fine" and ultra-fine standard threads. No country wished to yield to another. Consequently, there are no established standard fine metric threads.

I'm planning on single point threading M6x0.75 threads, and wanted to know the min/max/nom settings for major diameter and pitch diameter. Might as well make the screw correctly - especially if I am using an M6 x 0.75 tap for the mating female threads. Why am I making a screw? Because I am making a differential screw for an adjuster. One end is M6x1, the other is M6x0.75. The threading requirements for the two pitches are different.
 
WobblyHand said:
Yes! I was on that site, but somehow missed the table.

Only thing I can't figure out is how to copy the table... Can't cut and paste it, and it's not a downloadable image. It would be a lot of typing. Maybe I can view the source html and get it? It's worth a try!
Click to expand...
Three possibilities ...
1. Take screenshot(s), which you can cut and past, or just print
2. Hit "Print," but print to a PDF file. There are PDF editors available, if you want to get rid of the material you're not interested in.
3. Little Machine Shop has downloadable/printable tap & drill charts. Both are at
 
The table appears to be embedded in the html. I copied it and am pondering how to efficiently clean out the cruft that's not interesting. I initially started hand stripping out the html, but it's tedious. At least I don't have to type the table. I'm after the actual numbers to use in my spreadsheet.

@hman on #3, that will be helpful for doing the M6x0.75 threads in my tailstock. Thanks!
 
@mickri thanks for the table. I'm trying to get access to the numbers so I can enter it into my own spreadsheet. I wrote a python script to strip the html tags, but I'm having a little trouble with all of the regular expressions to get it to the point of exporting to csv. I know I can do it (eventually) but so far regex is kicking my butt. I have the lines separated, but I need to reinsert commas in the correct pattern. The table is very regular, so that helps a lot. There's 3 decimals of precision. Regex is like a language of its own - at the moment I am trying to decipher it. While I'm pondering regex, I am manually editing the table, which to be honest, is taxing my patience.

Like I said, regex is cryptic, these two lines delete all html tags, strip line feeds and start new lines if they detect an "M" in the file
Python: 
result  = re.sub('\<.*\>', '', line).strip() # strip out everything enclosed in html tags, and delete preceding white space
results = re.sub(r'M', '\nM', result)        # wherever there is 'M' substitute LF M

Haven't done anything like this before, so it is stretching the old brain cells. My parsed lines look like:
Code: 
M18 x 0.750.754g6g17.97817.83817.49117.42417.16616.962
M18 x 0.50.56g17.98017.87417.65517.56517.43917.257
M18 x 0.50.54g6g17.98017.87417.65517.59917.43917.291
One can figure this out manually, (but it is slow due to the size of the table) but making this exportable to csv, is what I am working on... Personally, I'd like to split the file to a 6g fit only and 4g6g fit only, as well as re-ordering the table from finest to coarsest.
 
Try Beautiful Soup for untangling the table from HTML, might have more success than rolling your own with regex.
 
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