DrDistillation

It's a bad idea because it's taking away from what could be fermented ABV wise. Typically you would want your mash to be so that when fermented it's the "perfect" ABV to carry the flavor you're looking for. For example 8.5% for a whiskey or brandy. Now if you were making a wash for a vodka you may use grains or cane sugar or combination and maybe upward of 14% if you can keep the wash from developing off flavors. So again you would want to maximize the ferment with sugar conversion to alcohol. The point of the ferment is to create alcohol on it's own. If you already have some alcohol like feints then you can combine that with the ferment when it's done and about to strip it. If you strip first then do a spirit run for vodka you may want to add the feints in during the strip to get a distillation from it and help remove flavor. But if these feints are for a whiskey you would likely not want to strip them again (loosing flavor) but would only add them back to the next strip run to help build a consistent flavor for each run. Make sense?

https://www.ncsl.org/research/financial-services-and-commerce/direct-shipment-of-alcohol-state-statutes.aspx#:~:text=Five states—Arizona%2C Florida%2C,%2C Oregon%2C Vermont and Virginia. might be worth a read. You guys might want to checkout: https://drizly.com/ https://thirstie.com/

Well, you really answered your own question about taste. At that high an ABV off the still you aren't going to have much taste left. You need to get that way down for a whiskey. For a pot still style run I'd strip fast and down to nothing left and you should have an ABV of 25%-28% or so in the low wines. This would allow you're spirit run to produce hearts right around the 160 proof mark and will slowly drop during the run. Tails will then be somewhere in the 130 to 110 proof range when they come over depending on grains and how clean your ferment was. After blending take your left over heads and tails and throw them into a feints container and mix them in with your low wines on the next spirit run of the same spirit. The combination of feints, sour mash and lower proof off the still should get you the flavors you're looking for.

Have you checked places like https://www.uline.com/ ?

Slickfloss, I know 5 or 6 different ways to use them to help with distillation. However anymore I think thumpers have fallen out of favor with packed columns and plates being easily used or doublers more in fashion at commercial distillers. Being able to control energy very easily these days the other advantages of thumpers is also diminished. I'd love to hear your comments that you deleted and it surely wouldn't offend me in any way. This is the way we all learn! With that said, the only real use of thumpers I do anymore is to put the grains in them for a fast strip run that is crazy smeared and fully flavorful, but most of the stuff I personally make these days is fermented off grain so...

Slow proofing helps to prevent saponification as well as help to preserve fruity aromas that are hard to keep in whiskey. Most people who make fine gins are well aware of proofing and resting and how it affects the botanicals, same with other spirits. Here's some light reading. https://blog.distiller.com/proofing-whiskey/ https://thewhiskeywash.com/whiskey-styles/bourbon/proofing-watering-whiskey-right-way/ “By allowing the molecules of the alcohol, water, and fatty acids time to bond properly, it helps preserve the fruity bouquet on the nose and intensity of aromas on the palate,” Fraley says. “We believe this process helps add a soft, silky mouthfeel to the whiskey.” https://issuu.com/artisanspiritmag/docs/artisanspirit_issue011_web/41 click the right arrow a few times to get to the Resting Spirits article. Do a test yourself and pull off a couple of gallons before bottling. Make the first your control and proof it down all at once as usual and bottle it. With the 2nd gallon proof it down slowly over a month. Now pull a 3rd gallon before bottling and proof that down. Now taste all the 3 the next day and you see a difference in all three.

What kind of information are you looking for?

Probably just a slower ferment whiskeytango. When you have a fast or violent ferment the CO2 rising up pushes up the particles and you get the cap. You can knock the cap down to help speed up the ferment or just let it fall on it's own if it develops.

Start your thumper about half full of either mash or low wines and it really can't run dry assuming it's just a thumper and you haven't added a heat source to the thumper (don't want to do this). BTW, you can't judge if it ran dry looking at it later because as your boiler cools down it will "suck back" juice from the thumper as the pressure changes in the boiler as it cools off. The way to stop this is to have a break or ability to open the pipe between the boiler and thumper and vent to the atmosphere. Typically this is done with a vent in the pipe of the boiler itself. This is always a good idea but with 2 SS kegs you're boiler won't collapse from pressure as it's pretty strong. If you use tri-clamps you can throw on gloves to handle the hot pipe and undo/break a pipe to prevent the "suck back" and get a true visual of what is left in the thumper. To answer your question, you can go very deep in the strip run until your alcohol meter shows 0 coming out of the still. Realistically the sweat water I mentioned is usually about 5% ABV as measured at the parrot/alcohol meter and your temp is 210 to 212F or 99/100C and basically just water left in the boiler while you drive what ever vapor is left in the column/riser out that still has some alcohol in it. So test the taste of this down low and see if it's worth keeping for each new spirit you make. Otherwise just do the math to see where the trade off of energy vs alcohol produced is worth it. A sugar wash is easy on your time and may not be worth running down past 15% coming off the still but a hard to sparge or higher cost grain mash is worth getting the most out of especially if it's just an electricity cost and not your time/work. Only you can decide this but if you get "something" useful from the strip run like sweat water that you can't get otherwise then it adds to your product if used wisely. Certain spirits produce sweat water worth using and some don't. I wouldn't bother with a bourbon mash but would with a 100% malted barley mash. With a Rum you can get some good oils down low that you'll want especially if trying to make "funky" rum or Jamaican style rum.. With a still your size it's worth experimenting as the difference in heating what you have left in the boiler is likely under a buck in costs which is nothing for a hobby/experimentation. I've got a test system similar to yours which is a 26 gallon boiler and 15.5 gallon 1/2 keg to use as a thumper. Basically exactly twice your size so I know the runs well.

However if you are using a thumper for the purpose of being able to ferment on the grain and distill it then you are GETTING flavors this way, not loosing them. You're able to get more flavor as well as not lose alcohol from discarded grains. With a thumper you can still run down low for fantastic flavor down to the 1 to 2% ABV (left in boiler) where lots of flavor resides but most people stop far short of, thinking they are wasting energy (but missing out on fantastic flavor). On a strip it's done quick and using a thumper of good size adds another benefit in that it allows you to strip more per run. From the standpoint of the op he could for example do 2 strip runs using the thumper and likely have enough to fill his boiler with low wines. Thus the energy spent on 2 strip runs with thumper vs 3 typical strip runs without thumper will almost certainly use less energy as well. The spirit run could then be done without the thumper or could be used with feints from a previous run to again bring over more flavor. So depending how you use the thumper you can add, not remove flavors. Not sure what the dilution part is about as you would not be adding water back later during the distillation process. Matter of fact, you can hold back the "sweat water" to use specifically to dilute the distilled product back down to cask strength adding yet more flavor in. You can even "oak" some sweat water to use for dilution after oaking is done as well. This would be impractical in commercial distillation but for the home distiller is pretty easy to do. Home distillers have it nice from the standpoint that an extra buck per run for electric is meaningless if it helps to produce a better product for them. Same with cleaning. A 7.5 gallon thumper is easy to take out side and house down to clean. A lot of things not practical to do in a big distillery are easy to do at the home/hobby level and can help to produce better spirits.

Yea and when you get time try a small 5 to 10 gallon ferment to see how much actual yeast slurry you actually need. Kveik yeast is known to like being under pitched compared with other common yeasts so you may not be doing yourself any favors over pitching it which it sounds like.

Two schools of thought on that. Some people actually keep ferments going on for many generations never taking more than 2/3 so the yeast stay alive to work the next batch. Other school of thought says if you have 2 smaller batches underway and plan on doing more combine the first 2 first so they will finish giving you something to run while the other ferment and finish a day or two later. This will require more yeast but if you manage yeast it's not a problem. People do both methods and I'd imagine you will get slightly different tasting mash/wort this way as well (good or bad).

Hard to know what to say except to check the pH and see if it needs to be raised. That 200 gallons of yeast slurry per batch sounds way over the top. What "constitutes" slurry. You could just have a lot of unfermentables in your wash due to this and the SG won't drop. Something I'd suggest doing is a small test. Make a batch in a single 5 gallon carboy or two and pitch a small measured amount of this yeast slurry to see how it works and how much is actually needed. Try two tables spoons and see how fast this kicks off. Have you tasted the wash? Still sweet or dry?

That's a high abv but not sky high by any means. Why did you top it off with more water and re-oxygenate the wash after it was almost done? What's the purpose of the mash? It it supposed to be a rum or something using light brown sugar? That won't have much molasses in it at all. What was the pH before pitching yeast? What is the pH currently and what's the temperature? Where did this Yeast Slurry come from? Why did you use so much? What is in it? 5 Liters of yeast would easily do that size batch as Kveik yeasts do very well under pitched.

Take a glass of whiskey and add a couple of drops of water to and and see how it opens up immediately after doing this. That is the chemical reaction taking place he's talking about. Generally if you can it's hard to do better than a slow addition of water to lower proof 1% per day then give it a month rest after doing this before bottling. Of course that's not always possible so you try to do what you can. Can you limit changes of proof to 5% per day and do a rest for 2 weeks? If you must proof down at once try to store/rest it as long as possible before it goes in the bottle. You'll have to figure out what works best for you and your production line but you won't go wrong doing slow proofing changes and giving spirits up to 5 weeks rest before it goes in the bottle.