Sciencemadness Discussion Board

Centrifuges

magnus454 - 14-9-2011 at 08:54

I found one made in china for $125 recently on E-Bay. It holds 6 tubes at 20ml a piece as ISO certification, it only runs on 220volts, 50hz, I acquired a 50W 110-220volt adapter, but it will still be running at 60hz instead of 50hz. I did the figures, and it will spin approximately 20% faster, the RCF's will be 2554 instead of the usual 1790. Talking with a few people, this shouldn't pose a problem, this should be enough since its a direct drive motor system, and not geared or belted it shouldn't draw too much current and damage the winding, if it were geared or belted, it very well could over amp.
I won't know true numbers until it arrives, I have a hand held tachometer (mechanical) that I can use to actually get a direct reading on it with, and also patch in my amp meter and take a reading on the motor at full speed. 20ml centrifuge tubes are difficult to come by, they make them in poly but haven't found any in glass. If there is an error in their specs, it may be that they are 15ml, or I can probably use some cheap poly tubes in 20ml to make adapters for 15ml glass tubes. What's nice about this if it works, is I get a faster centrifuge for the price, considering the voltage converter was 5$ with free shipping. If I need a higher wattage due to an error on my power conversions, no big deal either.

http://www.ebay.com/itm/220840246406?ssPageName=STRK:MEWAX:I...

http://www.everichmed.com/product/45-low-speed-centrifuge-80...


45-1194506475668-big.jpg - 30kB

Magpie - 14-9-2011 at 10:32

This looks good to me.

I bought a small Clay Adams centrifuge on eBay some years ago. The only thing I use it for is qualitative analysis where it is indispensable.

It is 115VAC, 1.5a, 60Hz. It will take 6ea 15mL centrifuge tubes but I normally only use the small 13x100mm test tubes - one for the sample and one for the counter balance. I don't know its rpm or g rating. I run it for 1 minute - it does the job. I can't find my sales receipt but it seems like it was around $100. It had been poorly packaged and was out of kilter when I received it. But I was able to make the simple repairs.

What do you plan to use yours for if I might ask?

Things

magnus454 - 14-9-2011 at 10:43

Qualitative analysis, purification of extractions, maybe some DNA work. Still need a thermal cycler for PCR, and a power supply and gel box for Electrophoresis. Love to get an electroportion unit and curvettes some day for gene splicing.

Electrophorisis chamber

Steve_hi - 14-9-2011 at 14:18

Here is one I made a couple of years ago easy to do
http://teach.genetics.utah.edu/content/build_gel_box.pdf

magnus454 - 14-9-2011 at 14:31

Hi, how well did the Electrophoresis chamber work for you? Looks good, I could use some high alloy stainless steel for the electrodes.

Steve_hi - 14-9-2011 at 15:33

To be honest I never used it it has sat in my drawer and is still a virgin but Im sure it will work it's quite simple. You could get stainless mig wire from a welding shop for the electrodes.

magnus454 - 14-9-2011 at 18:32

Yeah, I suppose I could get some high alloy stainless there. I have a 35 volt dc power supply lab grade for my electronics work, that should be good for around a 10cm chamber I believe.