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General Category => Equipment and Software => Topic started by: kylekohlmorgen on July 03, 2013, 01:40:54 PM

Title: Erlenmeyer Flask Size?
Post by: kylekohlmorgen on July 03, 2013, 01:40:54 PM
I am building a stir plate and looking at Erlenmeyer flasks.

My first instinct is to buy a 5L flask for high gravity starters and 10 gallon batches. Would this flask be too big for average-gravity, 5 gallon batches?

If I wanted to grow up a large pitch of yeast, could I just use a 1 gal growler?

Any makes/models I should stay away from? Pyrex brand is a bit more expensive, but the durability is fantastic.
Title: Re: Erlenmeyer Flask Size?
Post by: HydraulicSammich on July 03, 2013, 02:28:04 PM
I use a StirStarter brand plate.  I always do 5 gal batches.  I have a 2, 4, and 5 L Erlenmeyer. My go to flask is the 4 L.  Most of the time the yeast I have immediate access to is one to two months old.  But, my 5 L always works just as well on this inexpensive but good plate.
Title: Re: Erlenmeyer Flask Size?
Post by: AmandaK on July 03, 2013, 02:37:47 PM
I've grown tired of Erlenmeyer flasks breaking or cracking. I've had ones from the LHBS and Pyrex ones. I now use a glass cookie jar that I picked up for $4, that thing holds 3.5L and has lasted me longer than all of the Erlenmeyer flasks combined!  8)
Title: Re: Erlenmeyer Flask Size?
Post by: ns3580 on July 03, 2013, 02:52:31 PM
I have a 5L I use for everything from 5 to 15gal batches.  flexibility to do big pitches
Title: Re: Erlenmeyer Flask Size?
Post by: kylekohlmorgen on July 03, 2013, 03:03:47 PM
I've grown tired of Erlenmeyer flasks breaking or cracking. I've had ones from the LHBS and Pyrex ones. I now use a glass cookie jar that I picked up for $4, that thing holds 3.5L and has lasted me longer than all of the Erlenmeyer flasks combined!  8)

I was thinking that a mason jar would do just fine.
Title: Re: Erlenmeyer Flask Size?
Post by: Joe Sr. on July 03, 2013, 03:20:33 PM
I've got a couple of flasks and a whole bunch of growlers that serve me well for starters.

If I need a really big pitch, I brew a smaller beer as a starter.

I've got a couple 3 or 4 gallon carboys that work well for small batch starter beers.  And for trying out new recipes.
Title: Re: Erlenmeyer Flask Size?
Post by: klickitat jim on July 03, 2013, 04:27:23 PM
I have two plates and two 2000ml flasks. Use one for <big and both if doing >big or lagers
Title: Re: Erlenmeyer Flask Size?
Post by: thebigbaker on July 03, 2013, 04:30:04 PM
I have a 5L I use for everything from 5 to 15gal batches.  flexibility to do big pitches

+1!  I was lucky enough to find a starter set on CL that had a 1L, 2L and 5L flasks to go along w/ a stir plate.  I only use the 5L flask and the 1L and 2L flasks are just collecting dust on my shelves. 
Title: Re: Erlenmeyer Flask Size?
Post by: mabrungard on July 03, 2013, 04:46:39 PM
I have 2, 4, and 6L flasks.  Its the 6L that I use all the time.  Using the larger flask is better for even small starters since it provides a very large surface area for oxygen transfer to the wort.  I pump filtered air into the flask headspace to keep the oxygen content up and flush the CO2.  I find there is no need for a stone on the air line in this case and that helps avoid foaming. 

I do like Amanda's idea of using an alternative jar for starters.  Clearly, with a 6L flask, it will be crying time if I have a mistake with the flask. 
Title: Re: Erlenmeyer Flask Size?
Post by: AmandaK on July 03, 2013, 05:05:03 PM
I've grown tired of Erlenmeyer flasks breaking or cracking. I've had ones from the LHBS and Pyrex ones. I now use a glass cookie jar that I picked up for $4, that thing holds 3.5L and has lasted me longer than all of the Erlenmeyer flasks combined!  8)

I was thinking that a mason jar would do just fine.

I've used those as well. Problem was when I tried to find anything over 2qts - they got pretty expensive compared to the lowly cookie jar.
Title: Re: Erlenmeyer Flask Size?
Post by: klickitat jim on July 03, 2013, 05:13:50 PM
Seems like anything would work but metal and can't have too domed of a bottom or the stir bar has trouble. If I ever break a flask I probably will replace it with something with a dished bottom
Title: Re: Erlenmeyer Flask Size?
Post by: hopfenundmalz on July 03, 2013, 05:21:41 PM
I've grown tired of Erlenmeyer flasks breaking or cracking. I've had ones from the LHBS and Pyrex ones. I now use a glass cookie jar that I picked up for $4, that thing holds 3.5L and has lasted me longer than all of the Erlenmeyer flasks combined!  8)

I was thinking that a mason jar would do just fine.
I like your cookie jar solution. Looks like a flat bottom, and pretty cheap.
I've used those as well. Problem was when I tried to find anything over 2qts - they got pretty expensive compared to the lowly cookie jar.
Title: Re: Erlenmeyer Flask Size?
Post by: AmandaK on July 03, 2013, 05:28:24 PM
I like your cookie jar solution. Looks like a flat bottom, and pretty cheap.

I use the stir bars with the little ring in the middle : http://www.amazon.com/Scienceware-371100138-Magnetic-Integral-Diameter/dp/B002VBW5HW/ref=pd_sim_indust_7 (http://www.amazon.com/Scienceware-371100138-Magnetic-Integral-Diameter/dp/B002VBW5HW/ref=pd_sim_indust_7)

That seems to mitigate any problems with the slightly convex bottom.
Title: Re: Erlenmeyer Flask Size?
Post by: Scot (one T) on July 03, 2013, 05:41:42 PM
  I have 2 2L and 1 5L .  The only flasks that I have had break in 10+ years, are the ones I've loaned out.  I use the 2L for most brews and the 5L for lagers and larger batches.
Title: Re: Erlenmeyer Flask Size?
Post by: Jimmy K on July 03, 2013, 07:59:21 PM
Since you want to promote oxygen exchange, I don't think it can really be too big.
Title: Re: Erlenmeyer Flask Size?
Post by: davidgzach on July 03, 2013, 08:17:43 PM
I use my 5L Bomex directly on the stove to boil the DME, then cool and pitch yeast for all brews.  It's a nice and easy process.

Dave
Title: Re: Erlenmeyer Flask Size?
Post by: Pinski on July 03, 2013, 09:55:37 PM
2 plates, 2 2000ml, 2 5000ml.
Versatility and I usually do split 12 gallon batches so I'll often use two different strains of yeast.