Sunday, March 23, 2008

Metric Question!

Hey Metric Heads, we Americans are not as familiar with your system as we probably ought to be. Or at least this American isn't.... :D

Here's my situation: I'm playing with the FunnyBone drawings and looking at common metric wrench sizes. Now, the ideal size progression on my tool is 6,8,10,12,14,16,18mm.

It is my understanding though that 13mm is a very important and common size. It also happens to be very close to our American 1/2" which is an extremely common size here so I can see the attraction. My question is, how critical is 13mm? The reason is, if I include it then it throws off the whole progression of sizes on the tool and they need to be 2mm apart to work out and be stepped correctly.

So I guess I'm wondering, what are the most important metric sizes that the rest of the world needs? I have other configurations worked out if the above mentioned list isn't good enough.

26 comments:

Alex said...

13mm is a common size and in the auto world at least it is indispensable. With metric sizes, on cars at least, almost all sizes from 7-19mm are used. If you can't fit a 13mm in the main metric opening, maybe you could place it in the space right above the bit holder as it's own full size?

Maybe you could release a completely metric and standard FunnyBone (for instance one head of the metric would be 7,9,11,13,15,17 and the other 6,8,10,12,14,16,18).

Anyway, keep us updated, I am super excited for the FunnyBone, my Girlfriend is going to get it for my birthday if we happen to catch it!

Peter Atwood said...

Yes, that is what I was wondering, do I need to do an entirely metric Funnybone with the odd and even scales on opposite sides? I'd like to do the SAE/metric version though too so what would my ideal limited scale be?

Brian said...

Possible solution: Could you make the bottle opener a 13mm wrench or would that be a bit big?

Pat Galea said...

Peter, if you make the metric version really funky, you could end up being single handedly responsible for converting the US to metric. :-)

Peter Atwood said...

That was my first thought but yes, it is way too big to be the bottle opener.

Alex said...

I just found this chart that show equivalences.

Wrench Conversions

That may help a bit.

When I worked on cars I rarely ever used standard wrenches on anything. 1/4" came up often for small bolts on American brands, as well as huge sizes (1" plus), but I normally could get by with all metrics.

I don't know if this would be the same in other industries. A lot of American brand equipment is still standard, so for "around the shop" type stuff standard is necessary.

Peter Atwood said...

Great chart, thanks!

Joe said...

I am not sure if this will work. But, for the bottle opener, if you make the cap opening arm have a "hook" following the shape of a 13mm wrench, will that cure the "bottle-opener-too-big" problem? Your current bottle opener design has the two arms parallel, and I guess that makes a 13-mm opening too big. I hope my description is not too bad here and you understand what I mean. Good luck Peter ! :D

Anonymous said...

If i understand Joe correctly I think he means like the bottlebug.

Andrew Albinger said...

For bicycles 10, 13, 14, and 15 will get you almost everywhere.

-Andrew

Bolster said...

Peter, my father gave me a compete set of tools (including metric wrenches) for Christmas sometime in the mid 1970s. To this day I recollect that gift as one of the best presents I ever received. I rebuilt cars to put myself through high school and college, so those wrenches got lots of use.

To answer your question, I pulled out my wrenches and examined them for wear! Those with the most wear were: 9, 10, 12, 13, 14, 15, 16, 17. Others by comparison looked almost new.

aki said...

I will defer to the pro's we seem to have here in terms of which metrics are used most often ^_^

Good lookin out guys!

Ben Hamilton said...

Here in Aus, the spanners I use most are the 8,10,12,14,15,17mm.
More rarely are the 6 & 19mm.
Mostly bicycles, motorbikes, occasionally a 4WD.

Joe said...

Mr. Anonymous is partially right and actually brought up another potential alternative solution. The bottle bug has a hook on the "cap pressing" arm and I was thinking having the hook on the "cap lifting" arm. But I guess either way will work.

Marc said...

Well, just asked, so 8-9-10-13-17-19 seem to be the most used sizes. Hope that helps!

Matt Bobryk said...

Peter,
In my experience 1/2 SAE is the same as 13mm. I do a lot of wrenching on European and American cars and motorcycles, and I use those two interghangably. As long as you have a 1/2 or a 13mm on at least one side, then that should work. Save the space for an aditional size which would make the best use of space on the tool. That's one of the many reasons I love your tools, their so efficeint with space. Lot's of features in such a small tool!

Marcelo Kawakami said...

Hello Peter and friends. We, SI (International System) users, are so happy that you ask that. I'd say that 13 mm wrench are one of the most important size in a tool box. Normally is the first wrench that "walk way" when you let your tool box opened in the machine shop...13 mm is the size of the hex head for 8 mm bolts and nuts. By the way, why you guys still using the imperial system? I never get it, the SI is so simple and logical, everything is related: lengths, weights and volume. One liter of water weights one Kilograms and has 10 cubic dm. In the other hand, one pint of water weights how many oz (or lbs) and how many cubic in or feet? So difficult... Sorry guys, not my desire to be a pain in the a**, but I never lose a opportunity to mess around with metric system with my fellow Americans... Peace from Brazil.

Cuso said...

I personally use 10, 13 and 17 a lot!!

Anonymous said...

OK after some serious research and countless hours of thought I have come to the conclusion that a 19mm is the perfect size for the following reasons:

1. I usually play with my Attools while watching TV and have no idea what sizes my TV uses but it has 19different connecters on the back and is a Sony, thus I use a 19mm metric.
2. A 19mm flips around my index finger well.
3. Finally 19mm looks a lot like
9mm which is the caliber of handgun in my bedside table(HK USP 9mm)
Therefore it must be a 19mm. I stand ready for all counter arguments.

Marc said...

I would suggest to take the "conversion info" into account. Some metric sizes nearly match SAE sizes, thus including for example 3/4 and 19mm (3/4 being some 0.05mm bigger) or 5/16 and 8mm (5/16 being some 0.06mm smaller) is redundant. It would be enough to include the bigger ones, in said cases the 3/4 and the 8mm. Thus one could save space. Other matching pairs would be 19/32-15, 43/64-17 and 3/4-19. Don't know how that would fit into the progression of the tool and if it would be possible to step it correctly, though.

p said...

13mm is indeed indispensable working on any of my german cars, and I'd definitely want one. However, when you consider how many people will use this tool, the 1/2" substitution is probably fine.

Working on a car in the garage, this would never be my tool of choice...I might use it to figure out what size to get out of the toolbox, or if I just had to check to see if something was tight, but the first rule of wrenching is ALWAYS use something that gets the best grip possible on a fastener. In decreasing order of preference: 6-pts, 12-pts, open ended and finally something adjustable.

The FunnyBone is kind of an ideal emergency tool for on-the-road repairs, though, so I'd be less concerned about not having a perfect grip and doing a little damage to fasteners...it's more important to have the widest range possible. So, the 1/2" for 13mm is A-OK in my book.

Roger said...

Japanese motorcycles use 8, 10, 12, 14, 17. You won't see 13 on a motorcycle. Cars, on the other hand, generally use 10, 13, 17, 19. Looks like you need different tools for differently-wheeled users.

Peter Atwood said...

I appreciate all the great input on this. :)

I think I'm going to build a small one first, will be 3.5" overall length and 1 inch wide. Material will be steel and I probably will also do a run in titanium. No bit holder and hex on the smaller one but it will retain the bottle opener.

I'm going to cut a sample and check the sizes and ergonomics on it first before committing to a big run. I may also add scallops in places on the perimeter for extra grip.

I will stick to the even number scale on the metric end for now. I will count on 1/2" on the SAE side to do double duty for 13mm and that will be the best I can do on this piece. But it sounds like it will do a fairly decent job of covering the sizes for a tool this small.

There may be a spin off tool up the road as well... :)

Anonymous said...

hi peter,
have you finished the SharkTooth ? :D.. when will be the next release..:D
thanks!

Peter Atwood said...

Nope, still not done with the SharkTooth...maybe have some by next weekend by I'm just not sure yet. In the meantime I am grinding and also planning and arranging for future batches of items including the RingCutter and the FunnyBone. All this stuff takes time and unfortunately nothing happens by itself.

Anonymous said...

10, 11, 14, 15