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I cannot for the life of me find this style of clamp holder with beaker base: enter image description here

I can find beaker bases on sites like Fisher Scientific/etc., and flimsy alligator clamp soldering stands on Mouser/etc., but not this specific alligator (or other wire holding) clamp with sliding connector, on solid rod, attached to a beaker base.

Does anyone know what those sliding clamp holders are called, or where I can get this as a kit? I use this for e-chem and love it but need more.

Edit, 15-Jan This is an older version of my actual setup, which I would typically have on top of a magnetic stirring plate:

Setup

I would then be taking 2 of the 3 probes and passing them through a number of other poured solutions. My current clamping setup is great because I can simply release the counter electrode and just move my working and reference to different baths; really, I just need more of what I already have. As these experiments are limited in scope and do not require it, I do not make provisions for salt bridges, nitrogen purging, hydrogen gas aeration, etc.

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  • $\begingroup$ Isn't this off topic as the question itself is not about chemistry and the mentioned equipment is not specifically designed for chemistry? $\endgroup$ – GreenSmurf Jan 14 '18 at 19:51
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    $\begingroup$ I doubt there is a special name for those. Alligator clips are fine for keeping wires in place, but are unsuitable for holding the glassware. The setup on the photo looks a lot like a DIY project to me, probably someone came up with this design and used standard "crocodiles" to simplify the process of mounting and adjusting electrodes in the beaker. $\endgroup$ – andselisk Jan 14 '18 at 19:52
  • $\begingroup$ I think you would have more success on the Electrical Engineering Stackexchange or something similar $\endgroup$ – GreenSmurf Jan 14 '18 at 19:58
  • $\begingroup$ @GreenSmurf This setup is used specifically for 3-electrode cyclic voltammetry experiments. @ andselisk I have standing beakers that work just fine, but the electrode holding is quite helpful. I was hoping to avoid cheezy soldering setups. $\endgroup$ – PoGaMi Jan 14 '18 at 20:24
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Cyclic voltammetry (CV) is often performed in an enclosed vessel with the purge gas (argon/nitrogen) constantly bubbling through to prevent the solution from aeration and unnecessary side processes, mainly oxidation by the atmospheric oxygen. You'd rarely see alligator clamps in any CV apparatus also because they are not suited for holding moderately thick round objects (such as electrodes) in place, they can damage the inlet and outlet piping (e.g. the one for the purge gas, or chemicals if one studies kinetics), plus they make the experiments less reproducible since the position of the electrodes is changed each time you change the beaker.

Typically a teflon lid with 4 (or more) holes is used, where all 3 electrodes and the purging line are adjusted in place with rubber rings or plugs so that they are all firmly attached to the lid. This is very convenient since you don't have to manually adjust the apparatus every time the solution needs to be changed. All that's required is take the lid off, rinse the vessel and electrodes, fill the new portion in and put the lid back in place.

Alternatively, one can use a 3-neck round bottom flask with the electrodes attached through the rubber stoppers in the side necks. The downside is problematic cleaning, so this setup is more appropriate for the continuous measurements when one doesn't have to switch solutions too often. This is the simplest setup; a more sophisticated one can as well look like this:

enter image description here
Image source

Either way, I would discourage from using alligator clips for CV. Even though they might work for simple measurements, in my opinion there are too many downsides.

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  • $\begingroup$ I added an edit to my original post showing my setup. I really do just need the clamps that I have, not the more traditional CV setup, as I'm doing rapid device fab and testing in a bunch of different baths. If I find what I'm looking for, I'll post it here. If not, I'll just mark this as answered and use a soldering setup. $\endgroup$ – PoGaMi Jan 15 '18 at 17:17
  • $\begingroup$ @PoGaMi Thanks for the update; I think that beaker on the second photo looks too big for the amounts you work with. I'd just extend the electrodes (e.g. by soldering wires), put them in the lid, make the compartment smaller, and let the wired alligator clips lie somewhere aside so that they don't mess with the setup. $\endgroup$ – andselisk Jan 15 '18 at 17:23

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