no sparge w/ rims tube?

i just got a rims tube from brewershardware. i as thinking of a smaller set up and quicker brewday. instead of biab, how effective would it be if i put the total volume mash water into my 10 gal. cooler, add the grains and recirculated it thru a rims tube, then mash out the preboil wort? similar to BIAB, but w/ out the bag and using a rims tube. how would i start off when entering effeciency?


i have no problem adding more grains to simplify the brew day.

Thats hard to say for sure...
Honestly, you would want to run through a brew day to calculate everything.

With that type of setup, personally i get around 75-80% (i have a 2 vessel, and i do a backward hybrid fly/batch sparge thing) regularly, but i mill my own grain, i have false bottoms in my keggles that are electrically fired on a single tier.... so unless you have that same setup, i can't say what you're going to have lol.

But i'd aim for 65-70% and go from there.

I have done a similar thing before, and the results were pretty good. I mashed in with the standard amount of water, and heated my sparge water in the kettle. Instead of a once-through fly sparge, I just started recirculating all of the water through the tun and back into the kettle, while heating it. At some point the mash reached 168, and then I let it all run out to the kettle. I got almost 90% efficiency.

in almost all cases, claims of 90% efficiency or higher usually have errors in the math. its easy to be plus or minus a few cups of water here, a quarter pound of grain there... on small scales, small errors add up fast.

there is almost no way, without sparging, to get 90 percent efficiency. that would mean that you have end with a grain bed that has nearly all water removed and collected in the boil kettle. outside of using some sort of centrifuge, this is impossible. no offense to anyone, but thats just how things work.

see here: https://www.homebrewtalk.com/f36/how-much-water-does-grain-absorb-42932/

15% absorption rate is a pretty good estimate. so if you add 1 gallon of water to 1 pound of grain and drain it, you can expect to collect somewhere near 0.85 gallons back out of it. assuming everything else that effects sugar conversion is flawless at 100% (a fairly large assumption), you can expect efficiency of 85% at the very most without sparging.

OP- you will definitely loose some efficiency if you skip the sparge. sparging is the process of extracting the extra sugars that are in the grain after all the wort has been run off. if you dont extract them, then you leave them behind. however, on our small scales, it might only be the difference of 1-2 pounds of extra starting grain, so it might be worth it to you to simplify your process for the extra $2 it might cost you.

One reason why BIAB brewers get pretty good efficiency is because the grain bag lets them mill very fine. Second reason is that lifting the grain bag out effectively squeezes more wort out of the grain. In your plan for a no sparge system that is NOT BIAB, you'll suffer efficiency hit in proportion to the gravity of the beer.

However, there is the possibility of fly sparging by using the RIMS as an inline tap water heater if you engineer it just right. You'd need to run it as a dual voltage system so that you can get the power up for the sparge but it can be done.... in theory.