measurements, new and old

http://www.infoplease.com/ipa/A0001660.html

i know some use old arcane developers &c,
just in case you need to know how to convert
or what exactly 26 grains of xyz compounded into
37 drams of abc, mixed under subdue light
with 320 minims of mno,

if you need a conversion calculator this might help too
http://www.easysurf.cc/cnver8.htm

just be careful with the firkin, and good luck!

john

Thanks for posting this. I bookmarked the links.

Mark Overton

Last year I had to record a gas flow setting of 2 cm/sec in a gas chromatograph SOP, so I converted it to units of furlongs/fortnight and slipped that into the SOP. My peer level reviewer caught it and agreed to let it go, but no one else that reviewed the document mentioned it...

Kirk Keyes said:

Last year I had to record a gas flow setting of 2 cm/sec in a gas chromatograph SOP, so I converted it to units of furlongs/fortnight and slipped that into the SOP. My peer level reviewer caught it and agreed to let it go, but no one else that reviewed the document mentioned it...

Click to expand...

thanks kirk


- john

The Darlkroom cookbook, 2. ed. has tables on this from page 265 onwards, just punch the numbers into any 4-banger calculator.....

More importantly it has a very important table at page 275 : Teaspoon conversions, solving the riddle a certain blogger has been struggling with......
Anyone familiar with homeloading ammo will know that volumetric measures, like teaspoons and such is more than accurate enough to measure out very small amounts of powder.

Teaspoons are only more accurate when you have a material that is very tightly controlled as far as particle size and bulk density goes. With the wide range of crystals, powders, and other things that photographers have to measure, it's certainly not as accurate as even a cheap, modern scale can be.

Kitchen spoons vary in size and shape according to manufacturer. Kitchen measuring spoons are far better, but as Kirk says you should not use volume to measure out solids.

BTW, I have a complete set of the old Apotehcary liquid measuring graduates. Heavy thick glass things with the smallest about the size of your thumb and the largest nearly as long as your forearm.

PE

Over in EU there are of STANDARDS for these things, kitchen measures come in sets,
1 tsp = 5ml
1 tblsp = 15 ml
and one smaller which I call a pinch = 1ml

I have tested several og these kits, steel, plastic and from various sources, IKEA has a plastic kit that can be found in most of the "civilized world", they are all surpricingly accurate, and MORE than good enough for mixing Kaffenol...........

Other than that I'm a convined gram/ml guy and only offered this conversion table for those that wanna go from the mysterious US recipes to metric.....

Frequent appearance on many packaged dry goods: "Notice: Contents packed by weight, not volume. Some settling may occur."

I think that says it all.

Did you know that the west was won by 1000's of guys handloading 1000 000's of rounds on their kitchen bench using nothing but volumetric measures.
These guys did not have the money to buy fancy smchmancy weights, but they had to survive! Don't tell me it doesn't work I have 30 years experience proving that, all powder measures ever sold are volumetric devices, nearly all pistol ammo handloads assembled in the entire world are measured by volumetric methods, in USA alone we have around 8 million handloaders......

All that said, you misses the point, I think the table mentioned in the DARKROOM COOKBOOK vol 2 p. 175 can be valuable information to translate all the strange US recipes for Kaffenol, teaspoons and all that, into scientific measures, that was what I was after first and foremost.

The IKEA measures mentioned BTW, reflects US standards as far as these things goes.

Great if you develop film with buckshot.

YAWN

You simply don't get it: its the opposite its a roadmap to translate all those weird US recipes to modern standards....

I see someone's been using wolframalpha:
http://www.wolframalpha.com/input/?i=speed+of+light+in+furlongs+per+fortnight

Lee

Kirk Keyes said:

Last year I had to record a gas flow setting of 2 cm/sec in a gas chromatograph SOP, so I converted it to units of furlongs/fortnight and slipped that into the SOP. My peer level reviewer caught it and agreed to let it go, but no one else that reviewed the document mentioned it...

Click to expand...

Lee L said:

I see someone's been using wolframalpha:
http://www.wolframalpha.com/input/?i=speed+of+light+in+furlongs+per+fortnight

Lee

Click to expand...

Nahhh - I did it the old fashioned way - I looked up the conversions in my 18th Ed of the CRC Handbook of Chemistry and Physics, printed in 1932. I keep it on my desk at work as it's so handy.

OK - It wasn't completely the old fashioned way. I didn't to the math by hand, or even with a slide rule, I used a 1990-vintage TI-85 calculator.

In reply to posts #8 and 10, I would like to mention two facts not obvious to the casual observer here.

1. Kitchen flatware sets have teaspoons and tablespoons which vary according to manufacturer and style. There are also wide variations in the sizes of drinking cups. Both of these vary over a fair range and are not accurate. There are standards for measuring spoons and measuring cups. The variations can cause quite a "gotcha" if you use the wrong thing in the darkroom.

2. Gunpowder measurement is done by volume BUT two things hold true here. One is that the powder is made to very precise standards of size and shape for which the volumes are given in tables for the sake of precision and the other is that grains of powder are cut by the measuring device to assure uniform delivery of quantity. The old timers calibrated their powder systems by weight before they went to volumetric delivery, and they used powder that was uniform. Before the creation of corned powder, gunpowder was just a mix of the 3 ingredients and no method of delivery could assure uniform accuracy. In fact, powder trains were often surrounded by a haze of flammable or explosive dust due to the separation. Often the powder separated into layers in the powder wagons.

And, BTW, we had to calculate the speed of light in furlongs per fortnight back in the 50s. It was a popular request by physics professors in that era.

PE

analog what is that? said:

You simply don't get it: its the opposite its a roadmap to translate all those weird US recipes to modern standards....

Click to expand...

Many of the "old arcane developers" (OP) use grains, drams, minims etc., - it is by no means an exclusively "weird US recipes" issue. Most of those units of measure were inherited from Europe. Even those old measurements made clear distinctions between volume and weight (mass).

You inherited ALL from us kid!
Me I prefer French measures of course.............

Who is "you"?

analog what is that? said:

The Darlkroom cookbook, 2. ed. has tables on this from page 265 onwards, just punch the numbers into any 4-banger calculator.....

More importantly it has a very important table at page 275 : Teaspoon conversions, solving the riddle a certain blogger has been struggling with......
Anyone familiar with homeloading ammo will know that volumetric measures, like teaspoons and such is more than accurate enough to measure out very small amounts of powder.

Click to expand...

naaah

the folks who originated caffenol used teaspoon measures because caffenol is a "kitchen sink developer"
made from household materials, and why not use something that everyone has in their drawer, a teaspoon.
caffenol does not require exact measures, so it doesn't matter if the teaspoon measure is exact or way off ...
i haven't used a teaspoon to measure my caffenol in almost 6 years, and it works just fine.
i am not really sure what riddle you are referring to. a lot of the caffenol buzz now has to do with people
being exact / precise and scaling everything out, and adding things like salt or kbr or whatever
to turn it into an "upscale developer", rather than a "kitchen sink developer".

me, i eyeball measure, all my ingredients, and i am sure some of the folks loading rounds on their kitchen table
did the same thing. in the end it really doesn't matter, as long as you were too busy guzzling a rundlet ...

However, measuring powder on the table can lead to a squib. http://en.wikipedia.org/wiki/Squib_load

Your next shot might be your last!

PE

30 years of practiucal experience with handloading my own ammo, and being around a lot of newbies that came into this during the lastr decade, afyter "modern" equipment came on-line has told us a very important lesson : the most dangerous thing has been the modern "progressive" stations, where you in theory get one loaded cartrigde for each pull of the lever, after initial set-up. Admittedly they use volumetric powder measures, but that aint the culprit, per see, its lack if knowledge and experience, they don't know how to keep on top of things and loqad perform double or half-pulls on the lever, this faciliates a no-pwder squib load.... I got a pail with about 1500 duds from a beginner a year back, he lacks equipment for pulling bullets and gave up on the apparatus.... Its a hell of a job pulling all those bullets, some with double loads, some empty, bullets destroyed afterwards most of the time, anly recycleable resource is primed cartridge shells, powder to be burned in the back yard....

But it wasn't the powder measure, it was lack of knowledge!