measuring beakers

[Jim C.]

Just finished mixing up some E6 chemicals and I found myself using 2 different beakers one a
paterson graduate and the other was a graduated pill cup for the small amounts, the marked
measurements always differ in my experience ( 500 ML in the paterson graduate was more in a Jobo container )
and wondered what everyone here uses as measuring beakers ?

[Eric James]

As you've discovered, beakers aren't very accurate. You can purchase inexpensive graduated cylinders through Amazon.

[Greg Lockrey]

Since most of my E-6 is limited to 500ml or 1000ml solutions I use 10 ml graduated pipettes to draw down my chemistry. Each pipette for a specific chemical. They are very accurate and being consistant is the name of the game for color work.

[Jim C.]

Greg, I hadn't thought of using pipettes for measuring out small quantities, are you using the disposable polypropylene type ?

[Nathan Potter]

As Eric mentions, use graduated cylinders like chemists use. I use glass or plastic syringes for small amounts.

Nate Potter, Chicago IL.

[Eric James]

Good recommendation Nathan. Plastic syringes for medical and laboratory use come in 1, 3, 5, 10, 20, and 50(60) ml. The latex-free rubber portion of the plunger may not stand up to E-6 chemistry unless you rinse them well with water.

[Drew Wiley]

For critical work I use polymethypentene cylinders from LSS. Solutions don't stick to
the edges like cheaper plastics, and they wash out more thoroughly. For casusal work
measuring cups etc are OK, but are virtually never really accurately marked.

[Greg Lockrey]

Greg, I hadn't thought of using pipettes for measuring out small quantities, are you using the disposable polypropylene type ?

The glass type with the valved squeeze bulbs. Glass is easier to flush out for some reason.

[kmack]

My past dealings with http://www.pelletlab.com/laboatory_glassware have been positive.

[Jim C.]

My bad in using the 'beaker' word, I am using a graduated cylinder ( Paterson brand )
but like I had mentioned it's the measurements molded / engraved on the cylinder
I'm suspect of, I've been thinking of getting calibrated cylinders or traceable ones,
or am I being too critical ?

Greg - thanks for the info on the type of pipette you're using

[wclavey]

Digging back into the dusty reaches of my memory through the way-back machine, as Wayne might say, if you have 1 or 2 or 3 commonly used volumes I always found it handy to have a volumetric flask. It has no markings on it except on the neck, where it has a single engraved line that marks the point where when the meniscus of the liquid in the flask touches that line (generally, at room temperature) the volume is exactly the stated volume. I ran a reaserch lab at Columbia for 3 years and this was the handiest way, short of a mechanical dispenser to do set-ups using the same volumes - - and they are much more accurate and a lot cheaper than the mechanical dispensers were at that time.

For smaller volumes (<=100ml), as described above, we used glass pipets, with a pipet bulb for hazardous or biological materials.