Thread sizes below 1/4 confusing

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moparspares

moparspares

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What is a No 10, 8, 6, 5, 4. What does this mean. Do metric threads fit these. I want to buy 10 - 24 nuts however most of these sizes i find are metric. I have read M5 .8 will also thread on. Is this true?
 
Yes some standard and metric thread sizes and pitches are close enough to interchange.
 
moparspares said:
What is a No 10, 8, 6, 5, 4. What does this mean. Do metric threads fit these. I want to buy 10 - 24 nuts however most of these sizes i find are metric. I have read M5 .8 will also thread on. Is this true?
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Those numbers are the ones given to the thread diameter of the screw itself.
Thread pitch on Metric, and SAE are different, so they don't interchange between the two.
Never tried to use M5, but it certainly wouldn't be proper.
Why are you having trouble finding 10-24?
That's a common size.
 
These screws are common as common gets. For example, the common hardware holding your electrical wall switch plates and outlets trim plates on are commonly 6-32. Just google "machine screw thread size chart" or similar...................

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It is important to understand that these are "common" and "standard" sizes. Holley carbs, for example, "back in the day" never used standard thread screws. Guns.....AMERICAN guns commonly use specialized threads different than common machine screw sizes
 
hemi71x said:
Those numbers are the ones given to the thread diameter of the screw itself.
Thread pitch on Metric, and SAE are different, so they don't interchange between the two.
Never tried to use M5, but it certainly wouldn't be proper.
Why are you having trouble finding 10-24?
That's a common size.
Click to expand...

Its a speciality nut I am looking for. It has a Hex Nut with a free spinning washer with rubber backing. It's 10 - 24 with a 5/8 washer. It holds on mouldings on an imperial and the rubber stops water intrusion into cab, trunk etc. www.clipsandfastners.com have this type but most of them metric sizes.
 
try Restoration Specialty Supply.
Look through their pdf catalog and if you can't find what you need, call, send an e-mail or both.

There are several differences between "Metric" and "American Standard."
I use quotes because these names are generally what people use, but if you're in the industry, then you'll be even more specific.
One difference is thread form. This is the shape of the thread in cross section, and the hieght relative to the diameter, etc.
Another is the dimensions - obviously.
And maybe almost as obvious is the designation method. Standard used nominal diameter and threads per inch. Metric uses diameter and pitch.

You asked about under 1/4" designations.
IIRC correctly these originated with gage sizes. There's a formula you can use to figure out the diameter, if you remember it.
diameter = .0600 + .0130 x size

Try it out.
Size 0 is what diameter? 0.060"
How bout a 10-32?
.060 + 10 x 0.013 =
.060 + .130 =
0.190"

For 0 and 00, use -1 and -2.
 
OP is AU, correct?

Not sure his light switch plates are the same as ours.
 
i wonder if you can buy some sheetmetal roofing screws an pull the sealing washer off of it?
 
YY1 said:
OP is AU, correct?

Not sure his light switch plates are the same as ours.
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Yup Looks like Queensland.
Must be some ironmongers or specialty houses with Unified/USS/Imperial/Whitworth & British Standard fasteners. But maybe no more convenient than if he can buy the correct ones from a specialty house here.
Look at the trouble even we have getting fasteners that used to be common here. :(
 
Try McMaster Carr? Good luck navigating their website.............
 
Question for OP-

What is "normal" for you regarding small fastener hardware sizing?
 
Yeah Qld, Australia. We are all metric here but of course you can buy imperial sizes but anything even slightly offbeat and your out of luck. I called about 10 fastner places the the other day and some had never heard of the free spinning washer nut and one guy even said they dont exist. I said they do I have one in my hand. I was at a fastner place yesterday to buy some more 10 - 24 threaded rod and out he comes with it. On the tag it says 3/16 and then says same as 10 -24. Yeah my whole point bloody confusing.
 
maybe if you guys had shaken of the yoke of imperial oppression, you wouldnt have this problem now, would you?

 
moparspares said:
Yeah Qld, Australia. We are all metric here but of course you can buy imperial sizes but anything even slightly offbeat and your out of luck. I called about 10 fastner places the the other day and some had never heard of the free spinning washer nut and one guy even said they dont exist. I said they do I have one in my hand. I was at a fastner place yesterday to buy some more 10 - 24 threaded rod and out he comes with it. On the tag it says 3/16 and then says same as 10 -24. Yeah my whole point bloody confusing.
Click to expand...
Well don't let the bewildered and clueless confuse you.
You now know the American or Unified thread system.
Not to be confused with Whitworth or British Standard. yet again different thread forms and designation method.

3/16 = .1875
10 = .1900
But 3/16 is not a proper American designation.
There is a British Standard Whitworth 3/16-24

Knowing the search engines sometimes limit geographicly, here's the place I place I mentioned earlier.
Restoration Specialties & Supply, Inc.
 
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I believe the term is "captive washer".

Not to be confused with integrated washer or washer head, which do not spin.
 
"But 3/16 is not a proper American designation."

That is correct. Per ASME, or per SAE, there is no such thing. It's a #10.
 
Many fasteners "do not exist" because the auto manufacturer had them specially made, and nobody else ever put them in stock, or had any use for them. So when they were all used up, there were no more made. A 10-24 nut with a 5/8 captive washer "does not exist". You can look thru every catalog like McMaster, Fastenall, or Graingers, and you won't find those. Add to that the integral rubber seal, and finding them just became 100X more difficult. What you will be able to find is regular 10-24 nuts, 5/8 (or so) washers with a 3/16 hole in metal and/or plastic, so that's what you'll need to use. You could superglue the 3 components together or something (I'm assuming the reason for it all being integral is for ease of assembly). McMaster p/n: Nuts 91841A011 $3.77/100 , .450 dia #10 Nylon self-retaining washers 91755A220 $4.61/100 , 1/2" dia. #10 washers 92141A013 $3.30/100 , 1/2" x #10 rubber washers 90133A017 $10.33/100 .
 
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