yeast shaker RPM

[enkindler]

I know that magnetic stirrers are all the rage but I like big old complex things and thus I picked up the following at an auction for a song.

It is a lab orbital shaker, with heat.

What do you think the idea mix RPM would be and do you think this is as effective as a magnetic stirrer?

I was planning on putting in a ramp/soak pid to control the heat (goes up to boiling) with the idea that I should be able to automate starter boiling and stirring.

 

[Hex]

Jealous. Only recommendation is to test the machine with water only in a flask first. It is going to depend on the radius of the orbital...my guess is 120 rpm. Interested in hearing more about this project...

 

[CrazedArmadillo]

I work in a lab growing bacteria, and we always incubate/shake at 120 rpm (never magnetic stir bars). I would guess yeast would also do well at that speed.

 

[enkindler]

Thanks Hex and CrazedArmadillo, I'll do some water tests and start at 150, I may have a beer to keg in a week or two so it may just be worth it to do some experiments.

I think the temp rating on this unit is a bit ambitious as the heater is a little weak but the shaker and the blower works well.

I may have to adapt a new electric heating element and I may also re-insulate it with ceramic fiber board.

At that point I may just turn it into the control unit for the fermtroller project that I have been putting off.

Even if the heat doesn't work I will have capacity for 9 2L flasks for close to the same cost as a mag stirrer

Now had I not passed on the -80C under-counter freezer that went for $250 I could have been making long term cultures from dozens of unfiltered beers.

 

[BioBeing]

You are not going to get something like that to boil your liquid. It might be able to hold the air inside at ambient +60C or so, but probably not much more.

And you can shake at 250 rpm or more if you like. The harder the better really - you can't over do it, as long as you are not splashing the liquid out of the flask.