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Mark Bacchetti
01-17-2005, 11:48 PM
Do you guys have to learn the English unit system too?

I hope not... switching between the two suck. http://fsae.com/groupee_common/emoticons/icon_mad.gif

-Mark
Cal Poly Pomona

Mark Bacchetti
01-17-2005, 11:48 PM
Do you guys have to learn the English unit system too?

I hope not... switching between the two suck. http://fsae.com/groupee_common/emoticons/icon_mad.gif

-Mark
Cal Poly Pomona

Ashley Denmead
01-18-2005, 02:45 AM
why bother learning anything but metric and SI, if your are....your living in the past!

haha

ash

Frank
01-22-2005, 08:16 PM
i use length measures in "imperial" quite easilly,

you have to, so that you can deal with components made in other countries

thou, fractions of inches, and inches dont bother me at all

i learnt to convert spring and damping rates so that i can talk suspension, and of course pounds to kg

fasteners are a big thing, especially as you have a hard time finding "exotics" in metric (such as 1/2 height heads, jam nuts, predrilled etc)

we're usually stuck with tube thats inch diameters, rod ends with UNF threads, and any machinery thats US or english made will be inch everything

i still get pressures mixed up

generally we get quick at converting back to metric

as for "imperial" units of volume area temperature velocity, i try to avoid them altogether, and use a conversion table to get them back to metric initailly

executive summary, if the calculation involves converting using the number 25.4 or 2.2 we're ok, otherwise its time for tables and charts.

The worst thing is those damn BSP NPT and Dash fittings (not to mention random metric threads thrown on some things), plumbing really sux ass.

I find it difficult to understand why any country would still "teach" science/engineering and refer to non SI units

Denny Trimble
01-22-2005, 09:02 PM
We're taught in SI units in our classes, with some imperial thrown in. But when it comes time to get anything done in the US, it's 80% imperial and 20% metric.

James Waltman
01-23-2005, 01:15 AM
We use the convert program from joshmadison.com like crazy. There might be better ones out there but I never bothered to look.

http://www.joshmadison.com/software/convert/

NovaCat2005
01-23-2005, 11:26 AM
Do "SI Unit" based teams only buy metric tools?

The imperial system is simply insane and everybody knows it, but it will never go away. To make the experience less mind numbing all of my engineering classes use SI units. The thing I love about the SI system is that power is always watts, mass is always grams, and everything is base 10. Having a 2 horsepower microwave just doesn't make sense. http://fsae.com/groupee_common/emoticons/icon_wink.gif

Denny Trimble
01-23-2005, 12:35 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by James Waltman:
We use the convert program from joshmadison.com like crazy. There might be better ones out there but I never bothered to look.

http://www.joshmadison.com/software/convert/ <HR></BLOCKQUOTE>

I use the google bar in firefox or IE. Type in 600 cc in cubic inches, the result is:
600 cc = 36.6142465 cubic inches

70 foot*pounds in newton*meters:
70 (foot * pounds force) = 94.9072564 Newton * meters

jack
01-24-2005, 11:42 AM
i took a math test last week with a question on it that required you to convert mph to ft/sec. i didn't know how many feet are in a mile http://fsae.com/groupee_common/emoticons/icon_frown.gif i guessed 5200, so i was close...

when i see problems in that are totally in english units, even if its all in ft/sec or something where you dont have to covert, i allmost need to put it into MKS just so it makes sence.

Greg
01-24-2005, 05:06 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by James Waltman:
We use the convert program from joshmadison.com like crazy. There might be better ones out there but I never bothered to look.

http://www.joshmadison.com/software/convert/ <HR></BLOCKQUOTE>

One of the few smart things I have ever done was to put Convert on my USB thumb drive.

TomF
01-25-2005, 03:39 AM
Well once I had an exam involving imperial units. Measure in inches and force and moments in pound force and all that other crap. Luckilly I just studied some American textbook on brakes for Formula Student design. So I knew a lot of those conversion factors by heart, and was one of few who passed the exam. But it was quite unfair since we are never tought imperial units although one guy stated once that we had to know them because of literature.

Ben Beacock
01-25-2005, 01:04 PM
1" = 25.4mm
3/4=19.05mm
5/8=15.875mm
1/2=12.7mm
1/4=6.35mm

.065=1.651mm
.035=0.889mm

Those are by memory. I think that answers your question? Also.. our toolbox is a mess. :S

Ben

markocosic
04-05-2005, 12:53 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Do you guys have to learn the English unit system too?

I hope not... switching between the two suck. </div></BLOCKQUOTE>

Yes and No.

We're taught SI only, but there's so much old stuff (and American junk http://fsae.com/groupee_common/emoticons/icon_razz.gif http://fsae.com/groupee_common/emoticons/icon_wink.gif ) floating about that anybody who is 'practical' not just 'theoretical' also knows english units.

SI units rock for claculations, but english units are infinitely more practical for day-day making of stuff.

I'll use english units if making a set of shelves/planting trees/cooking. (think of the typicla sizes/distances/weights involved and compare them to the size fo the units and the english system is far more practical)

I'll use SI units in engineering though, so yes we know both but tend not to have to switch between them.

When you get metric coarse, metric fine, UNF, UNC, BSF, BSC, Whitworth, ACME and custom threads/fasteners on one vehicle is when you really have to start thinking! (or using the ine-size-fits all 4.5" electric spanner, and replacing them all with metric ocarse when you put it back together..)

BTW - 0.3048m is 1ft is the number you want to remember, as this is an exact conversion. From there 12" in a foot, 3 feet in a yard, 1760 yards in a mile - job is good, and no accuracy lost?

buddy
04-05-2005, 02:26 PM
On a somewhat off topic note, how are ratchet drives specified in SI countries? I have 3/8" drive and 1/2" drive ratchet at home (with associated sockets). If I purchase one elsewhere are my socket drives a physically different dimension corresponding to a standard metric dimension (say 12mm)? Just wondering.

buddy

Jarrod
04-05-2005, 04:12 PM
Every ratchet drive i have ever seen is imperial, even for purely metric sets.

FamousFrank911
04-18-2005, 11:39 AM
At our University we do have to learn each unit system. For example at an exam the 1st question can be in the SI unit and the 2nd will be Imperial.

They want us to lnow each and they strongly recomend not converting all imperials unit into SI because of conversion mistake.

If you don't switch between the two, one is not harder than the other, the equations are te same.

Rob86
04-18-2005, 05:16 PM
I like this website http://fsae.com/groupee_common/emoticons/icon_smile.gif

Online Converter (http://www.onlineconversion.com/)