Apera InstrumentsAI2801 Powerful Magnetic Lab Stirrer / Stir Plate, Speed Range: 0-2300 rpm, Max Stirring Capacity: 3000ml

Expensive but quality is top notch.

I'm a DIY kinda guy and I've build a few home made stir plates from computer fans and cigar boxes. While fun to make they had problems. They'd through the bar, it was hard to find the correct potentiometers for the power supplies, etc. So after the fan broke while making my last starter I broke down and bought a this stirrer.I like:1. Comes with two bars, each of which is capable of moving my 2000ml yeast starters2. Rubber feet prevent it from noisily rattling on my counter top. It's silent.3. Light weight but doesn't feel cheep. The switch has a green LED to let you know its on. The knob used to adjust the speed isn't too tight or loose, making it easy to adjust.4.Power supply is separate from the plate itself, making it easy to clean and pack away.5. Price. When pricing components for my DIY plates the cost was usually about $40. But then I'd buy the wrong part, or wire the potentiometer wrong and burn it out. I defiantly spent much more that the $59 I spent on this plate.I don't like so much:1. Diameter. The product description says it has a 3000ml capacity. I think they had cylindrical containers in mind when they wrote that spec. I use this with a 2000ml erlenmeyer flask, so the base diameter of the flask is appreciably wider than that of the plate. I works but is a bit precarious.2. The top surface is hard plastic and kinda slick, even with the moulded texture. I'd like a grippier, rubber surface to hold on to my often wet, glass container. I'm defiantly going to find a thin rubber sheet and glue it to the top of thee stirrer.3. It throws the bar at about a third of it's max dial setting in my 2000ml volume. Not a big issue for me because I don't need to stir that fast but there you go.4. The speed knob points to 12 o'clock at it's lowest setting and 9 o'clock at it's highest. I know its nit-picky but I wish it started at 6:00 o'clock. It's only an aesthetic complaint but I'm like that.Overall I'm very happy. There are only a few things I'd change if I designed it but it's totally functional and for the price compared to other commercial stirrers, you can't beat it.

Used it to grow yeast in an Erlenmeyer flask. Very easy to use. I boiled the stir bar (included) along with my wort. Place the flask on the stirrer before you turn it on, adjust the dial to your desired speed, then wait... So far I have had no issues.Taking away 1star. After 1 day of use, the dial adjustment will only spin as a higher speed. Not sure if this is normal, but it was definitely more adjustable when I first started using it.Update. Tried to use it for the third time and it no longer works.

I use this for DIY e-juice mixing. I have been making my own e-juice for a long time now and picked this up finally back in Feb. of this year. This unit does a fantastic job of mixing smaller quantities, 400mL or smaller amounts. When I try to mix around 500mL though I run into issues. The motor just isn't powerful enough to mix greater amounts than 400mL that are heavy in vegetable glycerin. If I keep the mL amount to 400 or below I have no issues but I prefer to mix 500 or more per batch. They claim a powerful motor that can mix in excess of 1000mL but that must be when stirring very thin liquids or something because even mixing 500mL e-juice at full speed this unit is not powerful enough to mix the ingredients at all. I have to manually mix it myself. I did not buy a lab stirrer so I can still manually mix my juice; that is what the machine is for.That very same mixture at 400mL or less is mixed very well with this stirrer. Anything more is a waste of time.Also the speed control is not the best. It goes from hardly moving to full speed quickly and I cannot mix anything properly without going full speed. I would have liked a bit more control over speed other than slow and full.So yeah, great lab stirrer but weak motor and just cannot mix larger batches that are heavy in VG. I'll be buying a more spendy unit soon. Something that can actually properly mix larger amounts.

Magnetic stirrers aren't all that complicated, it's basically a motor, a spinning magnetic surface and a stir bullet you put in whatever you are stirring. As such there are a LOT of very inexpensive options out there, which work just fine. This one from Apera Instruments is a really good step up from the bargain basement stirrers. I use these stirrers to make structured water with shungite, and the Apera handles 1 liter of water without batting an eye. I love the fact that it has both an on/off switch as well as an intensity dial. It comes with 2 stir bullets, which I really appreaciate, many of the less expensive ones only come with one. I have run this at top speed and it has never thrown the stir bullet off its axis. One of the things I really like about this stirrer is its small footprint, it's absolutely perfect if you are looking for something to have "out" or on your desk without taking up a lot of room. Ultimately, I appreciate the quality of this device, it's a pretty simple one and I've tried other cheaper ones and they tend to feel cheap. This one does not, and it does exactly what I want perfectly.