Odd thumper results query

[Orwellian Steeze]

Apologies if this has been discussed as I did my best to scour the forum for prior discussion on this.

I ran my first thumper session with some odd results. I’m on my fourth generation of UJSSM and the priors have all been run through a pot still setup with predictable results. Stripping runs through a 30gal milk can into a Sanke keg which was then fitted with the same spool and condenser and run to spirit. All good separating foreshots, heads coming out around 160, hearts around 150-155, and a precipitous drop off to low proof tails where the majority of oils and off flavors were cut out.

For the thumper run I assembled the same boiler with an elbow, spool, going into my downcomer and back out a separate elbow to condenser. It’s a mix of copper and steel and steel parts packed with copper mesh. The thumper was charged with some unpalatable heads and a touch of tails as recycling from the previous run, brought down to about 50 proof with water while the boiler was charged with beer from the UJSSM ferment which finished dry at about 20 proof as per previous runs.

The heads out of the thumper came out tasting very corn-forward and oily as though they were tails. The temp was consistent with previous runs through the pot still and output rate was identical. The proof throughout the whole run hovered between 120 and 110 until the very end of the run. Never going higher. The hearts came out nice but I’m struggling to understand why the heads were so oily. At the end of the run when cleaning up I noticed that my backset in the boiler smelled normal (a bit acidic) but the contents of my thumper smelled like pure corn water. I’m trying to understand how this happened and where I went wrong.

[LWTCS]

Internet says that corn oils are not soluble in water. Says corn oil is miscible with diethyl ether. Slightly soluble with ethanol which is why I assume it came over in your distillate.

[NZChris]

If you want to smear tails into your hearts, put them in the thumper. If you don't want the smearing, put them in the boiler with the wash.

[shadylane]

The thumper was charged with some unpalatable heads and a touch of tails as recycling from the previous run, brought down to about 50 proof with water while the boiler was charged with beer from the UJSSM ferment which finished dry at about 20 proof as per previous runs.

The heads out of the thumper came out tasting very corn-forward and oily as though they were tails.

Maybe charge the thumper with something that's already drinkable.
Put the "unpalatable heads" and tails back to the boiler.

[Yummyrum]

Can’t comment on Corn as not ever done it . But Rum heads work very well in Thumper , but tails need to go in the boiler .That order seems to make the separation more defined .

Thump is like Pot still though , got to keep power so that run time takes about 6hours from first drops . Thumpers will smear just like a Pot if you run too hard .

Personally , I don’t dilute heads in Thumper . It’s not the boiler .
Only dilute enough so that the thump tube is covered if I don’t have enough in there .

[Orwellian Steeze]

I appreciate the feedback on all counts, here. As I said, it was my first run with the thumper and I’m glad I’m able to refine going forward.

One thing I’m still unclear on, here, is why the proof coming out of the thumper remained so low throughout the run. I certainly understand the smearing based on inclusion of corn congeners from tails in the thumper, but shouldn’t physics still play the same song coming out of the thumper as in a pot wherein the lower boiling point of various alcohols indicates that they will be first into the condenser, whereas the molecular weight and high boiling point of oils/congeners should exist last, once the alcohols have been largely boiled off and the temperature progressively increases in the thumper?

[LWTCS]

Perhaps you're throwing a bit too much power at the system? That could contribute to the lower proof?

With the thumper it will hold proof a bit longer, but no mater what as the run progresses and the primary kettle surrenders more (and more) of it's alcohol the abv will steadily drop, just like it does with a basic pot still.

I'd give shady's recommendation a whirl and then see what your observations are?

[Orwellian Steeze]

That’s a possibility though as I’m running a 2100 watt element in a 30 gallon boiler to power that and the thumper it’s not something I’d considered. I’d assumed given that low amount of power for the system size it’d behoove me more to watch the temps (one thermometer in the elbow exiting the boiler, one at the top of the condenser column on the thumper end) than the power. I’ll try slowing it down (and leaving the recycling in the boiler or to kill weeds in my driveway) on this next run and see what happens.

[LWTCS]

Also, its super easy to get sort of distracted with the over emphasis of paying too much attention to collecting the highest proof possible. I certainly did for a awhile.

Try to focus more on the sensory aspects and that may help you arrive at your desired outcome? Balance is the artful part.

[Stags]

2100w is in no way too much power for 30g. I run 4000w in my ten gallon for strips and maybe 2100-3000 for a spirit run.

[LWTCS]

2100w is in no way too much power for 30g. I run 4000w in my ten gallon for strips and maybe 2100-3000 for a spirit run.

Ah, right. I missed the 30 gallon volume part. It does take more input to bring the thumper on line in a timely manner.