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Mash in a bag in a cooler

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urg8rb8

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Hi, I mash my grains in a bag but have the bag in a 10-gallon igloo cooler. So this is basically a hybrid of a BIAB and conventional mashing. I feel like the grain bag I have now it's big enough for the larger grain bill recipes. Know where I could get super large bags? Maybe I can go to Walmart or a craft store and make my own bag? If so, what materials are good for use in this application?
 
I do bag in a cooler also. I just got a wilser bag a couple brews ago and couldn't be any happier. My wort is very clean coming out of the cooler with a 1 gal. vorlauf and the grain practically jumps off the bag when I go to rinse it off. Much, much better than any bag I've used before. You just tell him the dimensions and he makes the bag to fit. I highly recommend them. The hop bags they sell are just as good. Well worth the price.
 
I also do BIAB in a cooler, works better for me compared to using the kettle. If the sparge slows down, just pull up on the bag a little.
 
I believe that is a very coarse mesh bag and not what you are looking for.

Polyester voile material is what you want, it is a very fine weave, very strong and filters well.
Thanks
wilser
Walmart has that too. I could get that instead.
 
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Thanks for all the feedback everyone!

What do y'all think about getting some Voile and make a "pillow case" to fit in the cooler? Should be good right? Do I really need to make a cylinder-shaped bag?
 
Thanks for all the feedback everyone!

What do y'all think about getting some Voile and make a "pillow case" to fit in the cooler? Should be good right? Do I really need to make a cylinder-shaped bag?

If your cooler is cylindrical a cylinder shaped bag will fit it best. If it is rectangular, then a rectangular bag fits it best. Best is subjective, if you make a bag and it goes into the cooler and doesn't bunch up when you add the grain to the water the mash doesn't care what shape the bag was. Just make sure the bag is big enough to hold the grain loosely, not jammed together, so the water can get to all of it and the sugar can be dissolved.
 
fwiw, Wilserbrewer sells BiaB bags, is an HBT member and will whip up custom size bags...

https://biabbags.webs.com/

Cheers!

I've purchased 3 bags for various coolers from @wilserbrewer, 2 for me and one for our homebrew club. Couldn't be happier.

Honestly wasn't worth my time and effort in trying to make this, and I do a lot of DIY for this hobby. Of course I did sew right through my finger nail in high school home economic class, so at least I know my limitations.
 
I also purchased a bag from wilserbrewer in case I ever wanted to try my hand at biab... I honestly havent used it yet but for the cost. Its a solid made product and wouldn't hesitate to buy another if I needed it..
 
They aren't that expensive. I'd just buy one.

I MIAB using a cooler and custom bag and it works really well. I saw an immediate jump in efficiency vs the bazooka screen I was using before (with everything else the same). Cleanup is a breeze. About the only negative is that my wort is cloudy with MIAB vs pretty clear with the bazooka and a decent vorlauf. That really hasn't effected the beer and the beers I've expected to be clear (like the Centennial Blonde) have been crystal clear.

I haven't used a Wilser bag simply because I bought something else first. When it dies, I'll probably order one from Wilser because he's a regular poster here and I like to support the community.

Bottom line - MIAB works great. I highly recommend it.
 
For my 5-6 gal batches I mash in a round igloo cooler. Wort is clear after vorlauf. I use 1/4 lb rice hulls.
After the mash and batch sparge I turn the cooler over to dump the grain into a trash bag. I rinse out the cooler with a hose.
I hit a pretty consistent efficiency.

Can someone explain how using a bag is an improvement? Seems like just an extra thing to clean that makes stirring the mash more difficult ... ???
 
For my 5-6 gal batches I mash in a round igloo cooler. Wort is clear after vorlauf. I use 1/4 lb rice hulls.
After the mash and batch sparge I turn the cooler over to dump the grain into a trash bag. I rinse out the cooler with a hose.
I hit a pretty consistent efficiency.

Can someone explain how using a bag is an improvement? Seems like just an extra thing to clean that makes stirring the mash more difficult ... ???
The bag just replaces all the extra hardware you put into your round cooler.
 
I see. I spent $41.50 on the ball valve, 1/2" fittings, screen (all stainless), and 1/2" ID tubing.
Only $27 for a bag.
 
I see. I spent $41.50 on the ball valve, 1/2" fittings, screen (all stainless), and 1/2" ID tubing.
Only $27 for a bag.
I'm currently using a $6 large grain bag but it doesn't fill out the entire round igloo cooler, so I'm looking for a bigger one.
 
For my 5-6 gal batches I mash in a round igloo cooler. Wort is clear after vorlauf. I use 1/4 lb rice hulls.
After the mash and batch sparge I turn the cooler over to dump the grain into a trash bag. I rinse out the cooler with a hose.
I hit a pretty consistent efficiency.

Can someone explain how using a bag is an improvement? Seems like just an extra thing to clean that makes stirring the mash more difficult ... ???
well for one thing you wont need to ever buy rice hulls again allowing more actual mash to fit..
I have been brewing all grain for 5 years now at least and have only tried rice hulls once and found I dont need them... if the filter /false bottom is effectively designed and doesnt plug up, and the flow is low enough they are just not needed. IMO they are bandaid for folks who recirculate or sparge too quickly.. and I crush at .030. with a bag you can crush finer which allows higher efficiency,
I have never needed to stir my mash after doughing in either... did I mention I average 91% efficiency?

If it were me I use the bag on top of the false bottom or bazooka tube otherwise flow will suffer greatly.
 
well for one thing you wont need to ever buy rice hulls again allowing more actual mash to fit..
I have been brewing all grain for 5 years now at least and have only tried rice hulls once and found I dont need them... of the filter /false bottom is effectively designed and doesnt plug up, and the flow is low enough they are just not needed.. and I cruch at .030. with a bag you can crush finer which allows higher efficiency,
I have never needed to stir my mash after doughing in either... did I mention I average 91% efficiency?
How do you get 91%??? So you mill into flour??
 
How do you get 91%??? So you mill into flour??
No I mill to 1.030 a credit card thickness as many people do. I made a typo in my last comment.
I use a long ulwd rims I designed along with cheap 24v $20 pumps recirculating at a low 1.5-1.8 gpm flow rate which prevents channeling.
I use a cheap bayou classic kettle for a mashtun with the bayou false bottom but under that I have 30" of fine stainless braid as a second chance filter to prevent my small rims pump from Plugging.
Point is it works well and I have never needed rice hulls or to remix my mash.. there are many ways to skin a cat, I'm just trying to share what works well for me.. I can only suspect most people huge 7gpm pumps with rims and herms recirc toi fast and create thier own issues
The highest I got was almost 93% efficiency once but its consistently right around 91% for non adjunct beers.
 
Going this route (bag in cooler) next year for 5 gallons and larger brews. I make to much of mess pulling the biab bag out of the kettle otherwise. Staying with the normal bag in kettle for 3 gallons and smaller though. thats easy. No mess.
 
Going this route (bag in cooler) next year for 5 gallons and larger brews. I make to much of mess pulling the biab bag out of the kettle otherwise. Staying with the normal bag in kettle for 3 gallons and smaller though. thats easy. No mess.

If you have a place to fasten a pulley above the kettle you can lift the bag straight up and just let it hang to drip. Check out bags from Wilserbrewer as he has ratchet pulleys that will let you lift the bag and then hold it for you.
 
I used my Wilser bag for the first time Monday. I use a HERMS, cooler with a manifold MT. I had him custom make the bag for my cooler. Thought about BIAB, but have always been a fly sparger. The bag made for easy cleanup, and I was amazed at how clear my runnings were. Made me wonder why it took me so long to get the bag. I was able to recirculate at any speed that I wanted. It was a 20 gallon batch of Saison and got 88% efficiency. I do wish my HERMS could ramp faster though.
 
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