Van De Graaff Generator, 325KV, With Humidity Control

Worked perfectly and as intended in my high school science class.

The quality of the comments for this product are superb and should be formally included in the instruction manual.Bruce points out that the base of the unit needs to be placed on an insulator (plastic) while the instructions from Lethan indicate "when the instrument is in operation, the main console / base should be grounded." I suppose I'll have to determine which advice is correct experimentally.Thanks to Skyking and techie67 for suggesting to add a copper collecting comb to the stock collector bar. Increasing the surface area of the collector truly is key to operating this device at its full potential. I ended up purchasing this 30mm bare copper braid grounding strap ( https://www.amazon.com/dp/B07MXCTQ2P ) and this 25mm conductive adhesive copper foil tape ( https://www.amazon.com/dp/B07D56B82F ) to attach the braided strap to the bar. I'll try to keep the 1/8" pickup spacing as per Skyking's findings. They'll be arriving tomorrow, so I'll update this review after I've performed the modification.According to Sci-Supply, "voltage is dictated by dome size", so I suppose Jenn and Dan's larger domes would produce >325KV, but I'm just interested in recharging N95 mask fibers and getting my nephew's hair to lift up, not trying to recreate the Tesla Wardenclyffe Tower 😂And speaking of fair price, guitarguy56, I snatched this up when it was $276.69 (before tax), the best historical price since Amazon started fulfilling it themselves in Sept. 2017. So, yeah, excellent value!Juan is right, though, about the grounding cable breaking easily. The plastic screw threads are just so brittle and cheap that they break off just from the force required to extract the banana plug. Just use your own, better banana plug leads.I concur with David Storm's assessment of the difficulty of placing the top dome over the bottom one. The tolerances are so tight that Sci-Supply recommends "placing the upper half in the refrigerator for 5 minutes." That doesn't make much sense to me. For one, wouldn't you want to actually heat the upper half to create thermal expansion so it slips easier around the lower half's lip? Cooling the lower half makes more sense. And two, cooling the dome below ambient temperature risks going below the dew point and collecting condensation on the inside of the dome, something they caution you on multiple occasions in their literature. As for his unexpected arachnid squatter, removing the two plastic side covers only takes 8 philips screws, so vacuuming that compartment out shouldn't be too difficult. But webbing ending up anywhere else would ruin the overall efficiency of the machine, so plugging the dome's hole with a sealed banana plug is cheap insurance.Mark's comment about an anti-static coating around the plexiglass tubing made me wipe down the tube's exterior surface with reagent-grade isopropyl alcohol. I didn't really notice any discoloration on my lint-free chem wipes, but I guess it dissolved whatever was on there. I'll probably do the inside as well. It isn't that hard to disassemble and I can wrap an alcohol-soaked wipe around a bristle brush to really scrub out any residues.The equipment itself is solidly constructed of two stainless steel hemispheres, sturdy plexiglass tubing, and rigid painted (though not powder coated) sheet metal for the base console, capped off on the sides with two plastic handles that come apart fairly easily with 4 phillips screws each. I attached some rechargeable desiccant canisters to each end cap to further reduce the humidity in there ( https://www.amazon.com/dp/B08NCZRHV2 ). My biggest gripe is about the packaging it shipped in. They used that styrofoam made of those compacted individual beads. You know, the kind that creates a ton of little electrostatically attracted particles if you so much as look at it? Those little packaging bits get all over the unit and I even found some inside the tube. Would it have killed Sci-Supply to vacuform a plastic bag/shield around the styrofoam padding to contain all that detritus? I'd feel a lot more comfortable packing the machine in there if I knew I didn't have to spend unnecessary time cleaning off that maddening waste every time I pull it out.

Out of the box, the generator produced little or no spark. Did all the standard fixes, such as cleaning belt and dome. Also cleaned rollers with alcohol and adjusted pickup spacing. Still no spark. I decided to add pieces of fine copper braid to the lower pickup. Instantly the spark could reach 8" or more. The copper braid I used is from a quality roll of de-soldering wick. Available here:https://www.amazon.com/gp/product/B008O9VLA2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1I cut two 1/2" pieces and fanned out one end of each, then used a small bit of masking tape to hold the un-fanned ends. Attach this to the lower pickup with the fanned ends close to the belt. If the copper touches the belt, no problem, the fine wires will be immediately pushed away when the belt runs. That's it. You should have an 8" discharge spark.Update 12-26-2019It may be best to leave about 1/8" space between the wire pickup and the belt.This generator is awesome, once it is working properly! The grandchildren were amazed.

My class loves the demonstrations. A great way to show static electricity.

It did not work right out of the box. I submitted a refund request and till date haven't received any email from the seller. I am very dissatisfied with the purchase and will not buy anything from this seller.

Somewhere in the ad, you brag that you double check quality of each Vandergraft Generator. Whoever does it is tightening screws inside it too tight. HAND Tight. Don't use electronic driver. We had to redrill some screws and replace them. It wasn't hard to do, but so easy to avoid.

I first purchase one of these for my company lab. I recently purchase a second one for personal use. I take it into schools for demonstration of static electricity and the traditional hair raising experiment. This model has a heavy duty motor and a heat source in the base which helps to reduce humidity in the base. The heat source increases the voltage output, producing larger sparks. The entire machine is ruggedly made. The custom foam enclosed shipping box make a nice protective carrying case for storage and for transporting the unit to various schools. The voltage output is higher that that of the other Van De Graaff generators on Amazon. It can give you a nasty shock is if you don't know what you are doing. Remember there are three types of electricity: that which can give you a shock, that which causes you to piss you pants, and that which can kill you. This has not killed me. You need a sturdy plastic stool. Metal will not work. I recommend the 10 piece accessories for demos. Belt is rubber, so lifespan depends upon use. It ages like rubber bands left in the desk drawer.

This is a fun toy and conversation starter. I live in Phoenix where the humidity is generally low so I can get 8" sparks out of this thing on a good day!