Great Article June Popular Science

[Dan Wright]

Issue features
Meredith Patterson
Open PCR
Cathal Garvey and his Dremelfuge
Great Job!

[ByoWired]

The concept of using a timer to "control" the temperature of an incubator is a burnt-down apartment complex waiting to happen.  Without some sort of proper temperature feedback (thermostatic control), there is a good probability that heat can build up over time and possibly set fire to the incubator, especially if the incubator is made out of something flammable like cardboard, etc.  

Also, since when does Carolina sell GFP, plasmids, etc. to Joe and Jane Schmoes?   Last I heard, they sell stuff like that to only schools and businesses - and they can be strict about exactly what kind of business they will sell it to, too.

 

[Meredith L. Patterson]

The incubator in question was a repurposed mini-fridge from The
Sharper Image, which came with a built-in Peltier to keep food and
drinks either hot or cold. It ran on 12V DC or 120VAC, and was
designed to be left heating for hours at a time, but only to one
temperature; that's where the lighting timer came in.

Carolina was more than happy to deliver to my apartment in SF. This
was in 2008; I don't know whether things have changed since then.

--mlp

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[ByoWired]

mlp,

I'm just guessing that in your particular case, with the Peltier doing the heating, the mini-fridge couldn't get very hot even if left on continuously forever and ever.  But I cringed when I saw that timer technique presented as a "good" idea.  No doubt other people are going to see that technique and use it because it seems straightforward.  And I am forever warning people about the dangers of these nifty thrifty DIY incubators made of flammable materials that will set themselves on fire if there's a glitch in the thermostatic control system.  Many DIYers do not seem to understand that temperature and heat are very different things, and if a thermostat goes bad and allows a heater to run continuously inside a well insulated box, the heater/box could get hot enough to catch on fire.  I've warned people that it's not the possibility of frankensteins escaping DIY labs that will get DIY shut down by the law, instead it will be the result of people accidentally reducing apartment complexes to ashes due to bad makeshift designs. But I'm afraid it's a warning that's doomed to fall on deaf ears because proper design translates into spending more money.  A non-flammable box (metal, fiberglass), for example, costs a lot more.      And DIYers pride themselves on doing everything on the cheap.

Anyway, fix your faulty thermostat when you get the chance.  And congrats on scoring some GFP from Carolina.  I think nowadays they are stupidly strict.   

On Wednesday, May 23, 2012 8:36:22 AM UTC-4, mlp wrote:

The incubator in question was a repurposed mini-fridge...

[Nathan McCorkle]

On Wed, May 23, 2012 at 10:16 AM, ByoWired <byow...@gmail.com> wrote:
> mlp,
>
> I'm just guessing that in your particular case, with the Peltier doing the
> heating, the mini-fridge couldn't get very hot even if left on continuously
> forever and ever.  But I cringed when I saw that timer technique presented
> as a "good" idea.

> Anyway, fix your faulty thermostat when you get the chance.

Maybe Meredith had a potentiometer or current controlled power supply
to adjust the temp, and was cycling between ON temp and NIGHT temp or
something...

--
Nathan McCorkle
Rochester Institute of Technology
College of Science, Biotechnology/Bioinformatics

[Tom Randall]

Carolina was more than happy to deliver to my apartment in SF. This
was in 2008; I don't know whether things have changed since then.

I think Carolina has changed policies. They will ship things such as spatulas, stir bars and other equipment to your home, but chemicals (or plasmids) they wont.
Those I simply have them ship to my work address if I cant find elsewhere. Of course, I live in Carolina, so maybe that is the policy within the state for them. Going through Chemsavers.com is a better option,
they always ship to your home.