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Allen Wrench Gage?

adamsgt

Cast Iron
Joined
Nov 7, 2007
Location
Fort Worth Texas
Have a lot of allen wrenches jumbled in boxes, including a box of hundreds I picked up at an auction recently. Question, does anyone make a gage similar to a drill gage that could be used to size allen wrenches for sorting? A google search revealed nothing as did a search on MSC. Failing that, does anyone know of a quick and easy way of measuring, Identifying and sorting allen wrenches? Spending hours and hours with a mic measuring allen wrenches could lead to alcoholism. :bawling:
 
A digital caliper, or even a dial caliper, is very fast to use.

Of course, I always first look for stamped markings. I prefer to use the USA brands with the size marked for actual wrench use.

If it says Taiwan, China, etc. or no marking at all, I throw it in a separate box. I use the foreign stuff when I need hex bar stock to make a little nut or cap screw. I draw the temper and machine it as required.

Larry
 
Not sure that a digital caliper might be faster than trying to find the right hole or slot. Anyway, like you say, it's a good excuse for lots of beer.
 
A fairly effective test gauge is to make a plate with a sample allen head screw for each size screwed in.
If you haven't got a screw that size you probably don't need a key.
Helps to pre-sort into several boxes of roughly similar size, have something handy that you can jam the best ones into as you go through. That way its easy enough to end up with a couple of sets of good ones. Time I had to do that I made some across corners hole gauges for pre-sorting.

if you have mixed metric and imperial in real small sizes, pray 'cos pretty much nothing else will help much. You could make hole gauges to nominal across corners sizes in metric and imperial. It will et most of them somewhere near.

Having sorted mark the imperials & metrics to keep them apart. I have one set where metric are silver and imperial black. Great idea.

Chop the doggy ones to have a short and long bit of hex. Great get of jail tools:- hook a spanner on for leverage, cut down and hook a spanner on where now't else will go in, weld a shank on when you need a real long one and so on.

Clive
 
Make a "taper guage" to test them for size. IOW, make up a dohickey with a tapered slot, slide a known wrench along it till it stops and mark your guage to that size, rinse,lather, repeat.

Tim in D
 
I had to do the same thing recently. I used some dial calipers and these figures from some known allen wrenches.

Allen Wrenches Sizes
Standard Approximately
1/16 0.0600
5/64 0.0770
3/32 0.0940
7/64 0.1090
1/8 0.1230
9/64 0.1380
5/32 0.1545
3/16 0.1865
7/32 0.2175
1/4 0.2490
5/16 0.3110
3/8 0.3745

Metric Approximately
1.5 MM 0.0580
2 MM 0.0775
2.5 MM 0.0970
3 MM 0.1170
4 MM 0.1560
5 MM 0.1950
6 MM 0.2350
7 MM 0.2720
8 MM 0.3155
10 MM 0.3930
 
1.5 mm is 1,5mm
2mm is 2mm

SI allows either the period (full stop), ".", or the comma, "," for use as the radix point, or separator between integers and fractional portions of the number. For international blueprints, SI does specify the comma as the radix point.

I thank God on my naked knees I am fully metric :cheers:

I am thankful that I am bi. Errr, bi-unit that is. Hmmmm. Bi-unit still sounds a bit abnormal.

I can work in both. And in wood working, it's much easier to use fractions when you are dividing dimensions in half. So I actually LIKE "English" customary units for that.

But you know, exquisite work has been done in all units. And Europe gave the world Whitworth and Loewenherz!

Best,

Jim

PS: To the OP's point, if you have some SHCSs in each of the sizes, you could tap and screw 'em into a piece of scrap, and label it well. Or glue it into a piece of 2x4. Err, that would be nominally 2 inches by 4 inches, which is really 1.5 inches by 3.5 inches.... Ok, so maybe there IS something to this metric stuff.
 
Make a "taper guage" to test them for size. IOW, make up a dohickey with a tapered slot, slide a known wrench along it till it stops and mark your guage to that size, rinse,lather, repeat.

Tim in D

This is probably the fastest way. I believe they make taper gauges for drills and a size is a size as long as you measure across the flats. Get an inch, taper style drill gauge and mark the metric sizes on it. Then go for it.
 
Thinking about the geomtery of this measurement.

EPAIII:

Your post is very thought-provoking !!! You wrote: " I believe they make taper gauges for drills and a size is a size as long as you measure across the flats. "

You just opened up an interesting new issue! One cannot truly measure "across the flats" of a hex wrench with a tapered-slot gauge. With perfect alignment, one would AT BEST be measuring between two corners (arrises) which have one arris in between them.

If the corners are not perfectly sharp arrises, then the reading between two arrises is not quite the same thing as the measurement across the flats adjacent to these arrises.

You've raised a whole interesting mathematical question about how the rounding of the corners would interact with the taper of the gauging slot depending on the angle of the slot !!!

(Also included in this is thinking about those slotted drill gauges. They are marked with drill diameters, but they actually measure a chord of the circle, not a full diameter. I never thought of this before you brought it up!)

You also shot down the suggestion I was going to make about calculating the size of the hole that various Allen wrenches would fit through and make a round-hole gauge plate. This idea founders when the issue of less-than-perfectly-sharp corners is considered.

OK, then the IDEAL Allen gauge looks something like an old-fashioned sheet metal gauge as made by Starrett or Brown & Sharp. Its a disc about 4 inches in diameter with PARALLEL-SIDED slots cut in the rim, one slot marked for each size.

I would not be surprised if such a gauge has actually been marketed, with suitable fractional sizes, for some purpose other than Allen wrenches.

What a great post, in terms of how much thinking about geometry it provokes!

John Ruth
P.S. Since the smallest Allen wrenches are not stamped with the size, I've considered coding them with colored stripes using the same code used for electronic resistors. Only problem is that the color black is used as a zero in that code, which would be a problem coding metric Allen keys. (Black paint does not show against a black Allen key.)
 
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Think how good you'd be with reading a mic!

I dumped out a good 2/3 of a 115pc drill index once and had only a mic to judge the smaller sizes which aren't stamped. Got a lot of practice that day. :willy_nilly:

Every time I get a bit out of the cabinet at school I check it with a mic that is laying on the
shelf right above. You just never know where a student has "replaced" a bit when they
return it. :-)
...lew...
 
The color coding works well. I just sorted all my old "keys?". (why are they called keys?)
Then I used different colors of electrical tape to color code some of the more commonly used sizes, very helpful when you have a boxfull.
I also just used digital mic calipers, (inch-metric of course, I'm Canadian eh!) Pretty fast but still led to some beer consumption.
Peterv, it is nice to know the inch size of a metric key as you often are measuring in inches and come across a metric key. Once you get familiar with the sizes you can spot them right away.

I was also amazed at the difference in tolerance within a given size. I can't remember the amount of variation but there were some keys that I just threw away, but now I will keep them for small bols etc as per post #2 by L vanice.

Love the PM!
Michael Moore
 
How about get one of those $4.99 sets of calipers with the cute little 3' tape measure and 6"rule. The plastic calipers are measured in inches and fractions, and cm/mm. True value had them in the garbage tool bin the last time I was there.
 
Jim,

"Err, that would be nominally 2 inches by 4 inches, which is really 1.5 inches by 3.5 inches.... Ok, so maybe there IS something to this metric stuff."

While I'm comfortable with both also, I don't think the metric is better in the quote above. I smile as I say that, not nitpicking.

Our 2 X 4 was AT least a full 2 X 4 many years ago, and has steadily shrunk as mills decided they could make more money from a given quantity of wood by selling smaller pieces for the same purpose at the same or ever escalating price.

Ask some of the older European members if they remember what their 50 X 100 mm studs were way back then, and if they are now sold as the same but measure 37.5 X 75 mm. Maybe that's a 5 X 10 cm stud, instead.

I'd eyeball the keys into approximate sizes then use a set or capscrew to finalize the sorting. If you have bigger ones without a capscrew to fit, 1/4 or 3/8 drive 6 point sockets will work They make them in metric, too.

I gotta admit, my own are piled into a toolbox with nothing else in it, not more than about 10 pounds. When I need one, I eyeball and try on a sample cap or setscrew. You get down to an .050, you probably should mike it.

Cheers,

George
 
1.5 mm is 1,5mm
2mm is 2mm
ASO ASO

I thank God on my naked knees I am fully metric :cheers:

According the the measurements provided by Ron of Va (converted to metric), 1.5 mm = 1.4732 mm allen key.

Or in Holland, are the allen keys sized for an interference fit? :D
 








 
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