littlebritishcar
Well-known member
I have a bucket full of mixed used nuts and bolts that I need to sort and organize. How the heck can I sort between metric and SAE? Some of this stuff is automotive that goes back to the 50s so it isn't marked.
How to tell Metric vs SAE?
- Thread starter littlebritishcar
- Start date
jkwilson
Well-known member
Thread gauge would be a good start. Older stuff is most probably SAE.
countryroad82
Well-known member
What JK said. Get an elcheapo thread gauge and start sorting.
Cyberbear
Well-known member
Being "old school" I never understood the need for metrics, but it's here to stay, I'm not.
Everything I work on is pre 1980, so no problem, I throw away all metric fasteners I run across.
You may find it easier at first to obtain metric threaded nuts in various common sizes and simply screw the bolts into the nuts until you develop the skill to size metrics at a glance, as I did many years ago for SAE fasteners, it's not that difficult. In order to make my life a little easier, I long ago bought a small bin rack and stocked fasteners from #8 up to 1/2" because I got tired of having to run to the hardware store each time I needed a dollars worth of nuts and bolts. This allowed me to buy grade 5 automotive instead of the **** grade 2 usually found at most outlets.
Everything I work on is pre 1980, so no problem, I throw away all metric fasteners I run across.
You may find it easier at first to obtain metric threaded nuts in various common sizes and simply screw the bolts into the nuts until you develop the skill to size metrics at a glance, as I did many years ago for SAE fasteners, it's not that difficult. In order to make my life a little easier, I long ago bought a small bin rack and stocked fasteners from #8 up to 1/2" because I got tired of having to run to the hardware store each time I needed a dollars worth of nuts and bolts. This allowed me to buy grade 5 automotive instead of the **** grade 2 usually found at most outlets.
nadogail
Well-known member
The stick with holes in it with the various sized bolts protruding through.
Works fine & lasts a long time.
Works fine & lasts a long time.
Buckgnarly
Well-known member
Grading on the head.
Metric=numbers, SAE=lines
Edit, for not marked I LOVE this set....or the larger separate sets at bottom...
http://www.amazon.com/dp/B00GB03OLU/?tag=atomicindus08-20
Metric=numbers, SAE=lines
Edit, for not marked I LOVE this set....or the larger separate sets at bottom...
http://www.amazon.com/dp/B00GB03OLU/?tag=atomicindus08-20
By the time you get half way through the pile you will be able to determine the SAE from metric glance. The bolt diameter is clue from a distance and tell the difference. Just by stank diameter metric will be 5,6,8,10,12 mm ......metric pitch after diameters sorted is no problem.
As mentioned grade marks are another easy to determine.
As mentioned grade marks are another easy to determine.
In many cases you can tell by the look of the fastener/threads. Usually metric looks like SAE fine but weird or off in some way.
But a more better/faster way is for bolts, use a set of calipers (best is digital with metric/English readings) to size the thread, SAE will conform to English measure. Metric will match Millimeter sizes fairly precisely. SAE coarse and fine look quite different and you'll get the hang of judging the difference quickly.
Nuts you'll be best served by a collection of known English and metric sized bolts to use as gauges.
But a more better/faster way is for bolts, use a set of calipers (best is digital with metric/English readings) to size the thread, SAE will conform to English measure. Metric will match Millimeter sizes fairly precisely. SAE coarse and fine look quite different and you'll get the hang of judging the difference quickly.
Nuts you'll be best served by a collection of known English and metric sized bolts to use as gauges.
maxpower_hd
Well-known member
Diddo on the thread gauges. They are only a couple of dollars or so and useful for other things if you work on the old rusty **** like I have and you break a bolt. And I have sorted piles of hardware too. You will soon identify the different ones at a glance only using the thread gauges for confirmation.
APEowner
Well-known member
This. sort the bolts first and then you can use them to test the nuts.
Personally, I throw out any hex head bolt with no marking. I have very few applications where an ungraded fastener is appropriate and I'm afraid that if I have them around I'll be tempted to use them "temporarily".
myredracer
Well-known member
Having both sux. 
Can never tell when something is gonna be metric or SAE ("Imperial" in Canada) when you buy it. Don't know if all Chinese stuff is metric? I'm forever trying a metric and SAE spanner or socket on things I know nothing about and sometimes when I think I know what it oughta be, things are a surprise. I was shocked to find that our '09 Ford SD truck is all metric. Our skid steer is SAE. Not sure what our travel trailer has, maybe both? Maybe a compressor can be either? Sometimes a metric wrench or spanner fits better on an SAE nut or bolt and vice versa. Sometimes an SAE bolt will fit better in a hole (or washers) sized for metric, and vice versa. What an unnecessarily complicated world we live in... Pffft.
I could go on (and on) but have things I need to do today.
Anyway, there's no big shortcut to sorting through metric vs SAE nuts & bolts. If you don't have a gauge and have some known nuts/bolts you could use those in lieu of. Or sort them all into like piles and take one of each to a hardware store (HD, Ace, etc.) and compare to what's in their open bins.
Can never tell when something is gonna be metric or SAE ("Imperial" in Canada) when you buy it. Don't know if all Chinese stuff is metric? I'm forever trying a metric and SAE spanner or socket on things I know nothing about and sometimes when I think I know what it oughta be, things are a surprise. I was shocked to find that our '09 Ford SD truck is all metric. Our skid steer is SAE. Not sure what our travel trailer has, maybe both? Maybe a compressor can be either? Sometimes a metric wrench or spanner fits better on an SAE nut or bolt and vice versa. Sometimes an SAE bolt will fit better in a hole (or washers) sized for metric, and vice versa. What an unnecessarily complicated world we live in... Pffft.
I could go on (and on) but have things I need to do today.
Anyway, there's no big shortcut to sorting through metric vs SAE nuts & bolts. If you don't have a gauge and have some known nuts/bolts you could use those in lieu of. Or sort them all into like piles and take one of each to a hardware store (HD, Ace, etc.) and compare to what's in their open bins.
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I found it is much easier and cleaner to just throw the old stuff in the scrap pile, go to your local farm supply store and purchase new - by the pound. I have always hated using old fasteners on a project. Just me but at less the $2.00 a pound my time is worth more.
Unless I have the grand-kids around and need busy work!!!
Unless I have the grand-kids around and need busy work!!!
four.cycle
Well-known member
thread gauge.
you can eyeball most of them after you've picked through enough coffee cans full of mixed-up nuts and bolts for years, but you're still going to get confused at times with 8mm x 1.25 vs 5/16-18 NC and 6mm x 1.0 vs 1/4-20 NC and.... on and on and on....
or get one of those gizmos that you can actually screw the bolt/nut into/onto like they have at Ace Hardware....
nahhh........
thread gauge. cheap. easy. idiot-proof.
you can eyeball most of them after you've picked through enough coffee cans full of mixed-up nuts and bolts for years, but you're still going to get confused at times with 8mm x 1.25 vs 5/16-18 NC and 6mm x 1.0 vs 1/4-20 NC and.... on and on and on....
or get one of those gizmos that you can actually screw the bolt/nut into/onto like they have at Ace Hardware....
nahhh........
thread gauge. cheap. easy. idiot-proof.
GYPSY400
Well-known member
Use a wrench maybe.. I.e: 3/8 bolt will be 9/16.. M10 "should" be 17mm
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
pmiranda
Well-known member
Thread gauge, a 6 year old kid/grandkid/nephew, and a bag of leftover Halloween candy
Seriously, from about 4 years old on my son loves playing with hardware like that, so might as well get some work out of that!
Seriously, from about 4 years old on my son loves playing with hardware like that, so might as well get some work out of that!
LS6 Tommy
Well-known member
^^^This^^^
FYI, a lot of the late 70's early 80's GM metric fasteners had blue painted heads, too...
Tommy
This set is fairly priced and fast to use. I find threads-per-inch edges to be a very quick hint as to whether I'm in metricland, or that archaic stuff.
Thexton THE432 Universal Thread Gauge
http://amzn.com/B003QI0MOM
Thexton THE432 Universal Thread Gauge
http://amzn.com/B003QI0MOM
bwringer
Well-known member
I agree that you'll be able to tell at a glance after a while. Next time you're in the hardware store, ponder a 1/4" fine (25tpi) bolt next to a 6mm X 1mm thread pitch bolt. Mathematically, they're very close (1/4"=6.3mm, and the thread pitches are within a few percent), but the threads look very different to me. And of course the usual head sizes are different -- 7/16" is a lot bigger than 10mm.
Same for 5/16" and 8mm. Diameter is very close, but the SAE threads are courser and look different.
Nuts are a little harder, but you can tell pretty quickly after a while.
The advice to scrap ungraded fasteners is spot-on. Same goes for anything with any visible wear, corrosion, or damage. Toss it out so you won't be tempted to compromise later on. Way too many people hoard vast quantities of dangerous rusty ****.
My old Suzuki motorcycle (all JIS metric) came to me with several 1/4" and 5/16" fasteners crammed in where they didn't belong, many with the original white or brown Briggs & Stratton paint... Grandpa's damn coffee can was the bane of my existence.
Same for 5/16" and 8mm. Diameter is very close, but the SAE threads are courser and look different.
Nuts are a little harder, but you can tell pretty quickly after a while.
The advice to scrap ungraded fasteners is spot-on. Same goes for anything with any visible wear, corrosion, or damage. Toss it out so you won't be tempted to compromise later on. Way too many people hoard vast quantities of dangerous rusty ****.
My old Suzuki motorcycle (all JIS metric) came to me with several 1/4" and 5/16" fasteners crammed in where they didn't belong, many with the original white or brown Briggs & Stratton paint... Grandpa's damn coffee can was the bane of my existence.
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csp
Well-known member
That works fine for SAE, but ever farm store I've been in sells metric by the piece, not pound.
rayra
Well-known member
I've used my racked sockets of both types as a sorting gauge. Metric threads got metric heads.
I just set the socket racks before me and size-check the pieces. It goes pretty fast. Hell of a lot faster than trying to thread things together in a known nut or threading die.
If you can use both hands semi-independently it goes even faster still.
And if you have a lot of material to sort, another trick is doing a big rough sort first, on vision alone. Get all the 'like' stuff grouped in their own piles and it makes it faster to run them all against the same socket. Instead of hunting and pecking one at a time.
But all that just works for standard-design-head bolts and nuts.
/i'm no fun building puzzles, either. efficient methods take all the fun out of it.
I just set the socket racks before me and size-check the pieces. It goes pretty fast. Hell of a lot faster than trying to thread things together in a known nut or threading die.
If you can use both hands semi-independently it goes even faster still.
And if you have a lot of material to sort, another trick is doing a big rough sort first, on vision alone. Get all the 'like' stuff grouped in their own piles and it makes it faster to run them all against the same socket. Instead of hunting and pecking one at a time.
But all that just works for standard-design-head bolts and nuts.
/i'm no fun building puzzles, either. efficient methods take all the fun out of it.
By sight. Either head markings or recognizing threads as previously mentioned. A good friend has a motorcycle shop and specializes in older Brit bikes. Just be glad you do not have Witworth and BSC fasteners in the mix that each have a different thread pitch.
ibedayank
Well-known member
Nope. BSC - British Standard Cycle. Also known as BSCy
>> http://britishfasteners.com/threads/cei.html