Fly Sparge Question

[Cantaloupe]

When I fly sparge I usually just keep the water going from the HLT until I get the preboil volume that I want, which generally leaves the mash tun full of water. Is there any advantage to fully draining the mash tun to finish off the sparge process? I have got 70% efficiency on my first two batches.

 

[gregpio85]

When I fly sparge I usually just keep the water going from the HLT until I get the preboil volume that I want, which generally leaves the mash tun full of water. Is there any advantage to fully draining the mash tun to finish off the sparge process? I have got 70% efficiency on my first two batches.

Do you take a pre boil gravity? The only thing I could think of is keeping the water in your mash ton to make slight gravity adjustments.

 

[Cantaloupe]

I usually take a pre boil gravity but we have always been within a couple points of where we want to be. Which prompts another question? Is a few points one way or the other a very big deal?

 

[statseeker]

If you're within a couple of points, I dont see a problem with that, not every brew is exactly the same without very good quality control and or elimination of several variables. I dont expect every brew to come out exactly the same in the specific style.

 

[Bru]

I maintain 2" of water above the grain bed untill I have my boil volume. I can't see any advantage to letting the MLT run dry. In fact you may get channeling.
Your efficiency could be better. I get at least 75%. Possibly try a slightly slower sparge and see what happens.

 

[Northcalais40]

I am in the same boat as you. I fly sparge and get about 70-72% eff. Nothing wrong with that. I consider the perfect situation to be: Full conversion in the mash, Very low final runnings SG (but greater than 1.010),and a good post boil volume and gravity.

I made a false bottom, because it seemed more suited to fly sparging, but was getting grain through the valve. I added a ss braid on the pick up tube (my FB is above the drain) and my efficiency went up to 76%. I think tis is due mainly to the braid getting a bit clogged and slowing down the sparge.

 

[sleepystevenson]

I always kinda wondered how everyone else went about this.

FWIW, I drain my mashtun entirely of sparge water to achieve total preboil volume in the boilkettle. It takes a few brewing sessions to establish and hone in your water/wort/grain soak-up volumes, but has been VERY repeatable and accurate since establishing a baseline. I can count on pretty much exactly 85% efficiency every time now for std. gravity beers. My mashtun has a full false bottom. I recirculate during the mash w/ burner to maintain temps and stir periodically throughout the mash and sparge (you can stir relatively close to the bottom without stirring up the runnings.)