More efficient steel braid based MLT Design?

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TheYoshi

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So I am sitting here (admittedly after a few beers) thinking about MLT designs, I really like the steel braid approach (my current setup) but got to thinking there are probably some ways that it could be made more efficient and friendly to fly sparges if one chose to go that route. The typical design is a steal braid up the middle of a cooler, works quite well and all but could potentially encourage channeling in a fly sparge setup, also the relatively small surface area of the screen is going to increase likelihood of stuck sparges.

I got to thinking, this could really be stepped up a notch by adding adding a T junction at the end of the straight piece of mesh and then putting two additional pieces that curve around the sides of the cooler (assuming round cooler). This would give a ton more surface area and drainage area for the good stuff to filter through, reducing the likelihood of a stuck sparge and also helping reduce channeling likelihood in a fly sparge setup. Here is a diagram of what I was thinking, please use caution when viewing, my illustration skills may blow your mind.

I think these are self explanatory but in case they aren't the mesh (crosshatch) areas are steel mesh, the sold areas are joints, everything else is labeled.

Design 1 - Simple Single point connection from central tube (click for enormous image), the shading at the ends of the side tubes is meant to represent a plug:


Design 2 - Dual connection points to central line from side meshes:


Design 3 - Ridiculous, at this point cost probably dictates that it would make more sense to just buy a true false bottom but here it is:


Two questions:

1. Thoughts?

2. Does anyone know where to pick up stainless T-joints and 4-way joints?
 
So I am sitting here (admittedly after a few beers).................


Have a few more beers.....:mug: All kidding aside, nice sketches.

The braid will always try, and will drain the wort closest to the outlet of the tun regardless of configuration. A short 6" braid will perform almost identically to an elaborate setup as you have shown IME. A false bottom w/ center drain w/ dead space is an optimal setup for fly sparging and reducing channeling.

Sorry to be a pundant.:mug: But IMO the braid lends itself to batch sparging.

If you really want to play, I would suggest a braid in a ring 1/2 -2/3 the diameter of the tun w/ the cross piece hard piped w/out perforations collecting wort from the center of the cross, this way the wort will be pulled evenly from four points of the tun, rather than just one point near the drain bulkhead.
 
Have a few more beers.....:mug: All kidding aside, nice sketches.

Beer produces some of my best ideas :D

The braid will always try, and will drain the wort closest to the outlet of the tun regardless of configuration. A short 6" braid will perform almost identically to an elaborate setup as you have shown IME. A false bottom w/ center drain w/ dead space is an optimal setup for fly sparging and reducing channeling.

Sorry to be a pundant.:mug: But IMO the braid lends itself to batch sparging.

I agree but to me that also means you have more opportunity for the place that tries to drain fastest to clog with wort and end up with a stuck sparge right? I think in general if one does get a stuck sparge it's going to be the filtering area that clogs, not the inside of the braid/tube, etc. if that's happening you likely have a bad filter setup (which is more or less what braids/meshes/etc are, just filters). I do think as clear wort enters the mesh it's going to want to flow but perhaps I'm wrong there... I could probably test this with some water and food coloring I suppose.

If you really want to play, I would suggest a braid in a ring 1/2 -2/3 the diameter of the tun w/ the cross piece hard piped w/out perforations collecting wort from the center of the cross, this way the wort will be pulled evenly from four points of the tun, rather than just one point near the drain bulkhead.

Yeah, a solid pipe to the center would certainly be ideal, the question still remains as to where to find SS connectors, may have to go with brass here...
 
My MLT setup is a 5gal rubbermaid with a circular braid off of a T. Like your design without the center piece. It's worked great for me whether I batch or fly. The liquid will be forced to the path of least resistance and most of it will get out of the cooler. I think the center piece just adds complexity with minimal gain (although it won't hurt). I think my setup would be less effective in a larger 10g cooler, though.

BTW you might need to reinforce the braid to maintain that nice semicircle. I've seen designs that insert 12gauge copper wire inside the braid to get it to hold a shape.
 
I just use 1/2 inch plastic tube tied to the inside of a bent double perforated stainless steel sheet (6 inches x 6 inches) the whole inside a very fine nylon bag and then a coarse nylon bag around that. I drain off liquid very fast and fly sparge. Works for me.
 
I've found that the wort tends to get attracted to the drain side of the cooler. You have to slow down the flow rate to keep it from channeling to one side.

Palmer has a great article on MLT design and it helped me immensely
This link is a good starting point:
http://www.howtobrew.com/appendices/appendixD-2.html

I tried a braided manifold and it worked, but I didn't see crazy efficiency over the single braid.

 
I would be cheaper if you just went with copper tubing and copper will last you longer.
 
I'm running a similar setup to jturie. I have a T coming off my drain valve, with a 4 foot steel braid that I have in a circle around my rectangular cooler. Been working fine so far. But I batch sparge :p
 
Palmer has a great article on MLT design and it helped me immensely
This link is a good starting point:
http://www.howtobrew.com/appendices/appendixD-2.html

I tried a braided manifold and it worked, but I didn't see crazy efficiency over the single braid.


Based on that article the 2nd or 3rd design I have would be ideal with the exception of needing to pull in my outer braids a bit from the cooler walls so they don't encourage drains right down the side of the walls...
 
I like the second one well enough, can't really speak in terms of efficiency. I'm assuming that for your braid you use the plain you can get from McMaster and you put the stainless steel "spring" coil inside of it?I think that is the BEST braid setup, no matter what!
 
I like the second one well enough, can't really speak in terms of efficiency. I'm assuming that for your braid you use the plain you can get from McMaster and you put the stainless steel "spring" coil inside of it?I think that is the BEST braid setup, no matter what!

Well I have a bunch of braid because I went nuts, one from the bargainfittings.com guy (who is fantastic btw, highly, highly recommended) which I'll likely use for my next batch as I'm formulating here and some I got from Home Depot (sharkbite hotwater heater connection hose, really great much larger diameter than most I've seen). This is the sharkbite stuff: http://www.cashacme.com/prod_sharkbite_flexhose.php they don't list it on HD's website but mine had it in stock.

The other I have is this stuff I got at a plumbing supply place here where I live (http://www.rffager.com/). It's probably the best braid I have and it was just some scrap they gave me, it's a bit smaller than the water heater connection but MUCH more rigid, the braid itself seems to be made of a somewhat heavier gauge wire. I can push very hard on it and not make it collapse, much harder than the other meshes I have would ever bear.
 
Based on that article the 2nd or 3rd design I have would be ideal with the exception of needing to pull in my outer braids a bit from the cooler walls so they don't encourage drains right down the side of the walls...


Yeah, that Palmer article really gets the head spinning...doesn't it? I wound up with two braids because I had 'em, like I said probably doesn't make a difference in the end...but that doesn't mean 4 wouldn't!
 
As promised in the PM, here are the pictures of my Mash Tun.

I think I should note that the center section (that connects to the ball valve assembly) is actually elevated a little bit, kind of like a dome tent. This way, the tube from the coupling to the manifold is completely level, while the manifold is still resting on the floor of the mash tun. This way, I do not have some strange contraption suspended in the air and stressing the braids.

MASH TUN 1.jpg


MASH TUN 2.jpg


MASH TUN 3.jpg
 
As promised in the PM, here are the pictures of my Mash Tun.

I think I should note that the center section (that connects to the ball valve assembly) is actually elevated a little bit, kind of like a dome tent. This way, the tube from the coupling to the manifold is completely level, while the manifold is still resting on the floor of the mash tun. This way, I do not have some strange contraption suspended in the air and stressing the braids.

I assume the fittings, etc. at the top is what you are using to add water? Nice way to do it as it will start the water flowing in a circular pattern helping the mash almost stir itself.

Interesting design here, I'm sure it's quite effective with all the drainage surface area. I actually came up with another thought after reading some of the posts and the article posted by shroomzofdoom. I'll post another awesome sketch in few.
 
I assume the fittings, etc. at the top is what you are using to add water? Nice way to do it as it will start the water flowing in a circular pattern helping the mash almost stir itself.

Correct, I recirc my mashout for clarity, and I found it much easier to generate a gentle whirlpool on top of the mash during fly sparging than some rain-down style contraption. I think it helps prevent channeling, but what do I know? When I was using a traditional 3 tier gravity sparge, I just wrapped a hose into the mash tun from the HLT, but with my newly built sculpture, the MLT is actually above the HLT, so I pump from my HLT up through the assembly at the top of the mash tun, and allow runoffs to enter my kettle through gravity. For reference, it is the exact set up of the B3 1550, but I only need to use 1 burner. The HLT and mash tun are both igloo coolers.

Joe
 
Ok, here's what I'll call my "final" design. Based on the fluid flow testing article posted by shroomzofdoom I think this makes the most sense, it gets the flow away from the cooler edges and keeps the spacing between drain pipes pretty much optimal without being overly complex.

I'm not sure you would need to bother with the T-joint at the end of the straight mesh but I like the idea of the straight mesh being linked to the round mesh, even if they don't flow through...

As usual, click the image for a giant version:
 

I am not sure about the center braid. Here's my thinking: by adding that, the wort will take the path of least resistance and eliminate the rounded sides (longer path, longer resistance)

Not sure if you saw this kind of design or if this helps, but hey...I am not a 'round cooler' guy, mine is square.

Braid_MLT_HBT.jpg
 
I am not sure about the center braid. Here's my thinking: by adding that, the wort will take the path of least resistance and eliminate the rounded sides (longer path, longer resistance)

Not sure if you saw this kind of design or if this helps, but hey...I am not a 'round cooler' guy, mine is square.

Well it's not exactly path of least resistance, it comes into play as to where the possible entry points are, if it was always path of least resistance even a copper pipe or cpvc pipe based design would have the same issue because the pipe closest to the drain would be the only one that gets wort flowing to it. In reality it's based on the nearest path to least resistance (there is likely a fluid dynamics name for this that I don't know).

That ring without the center piece would likely work just fine, just like a center pipe alone would work ok, but if you read the article here, you'll see that a much more optimal scenario is having multiple entry points for the wort into a path that ultimately leads to the drain but not too close to the walls of the MLT because that causes wort to just want to drain right down the sides.

By having the center piece you keep pretty close to optimal distance between potential drainage points (based on the afore mentioned article) but also keep a relatively simplistic MLT design. I mean you could have two concentric circles but that's more complicated to build without much benefit. This would be *relatively* simple assuming you could get the right fittings.

Also keep in mind the path of least resistance is always going to be inside the braid, the wort there can flow freely without any restriction from the grain bed.

I'm likely way over thinking this but hey, what fun is a hobby you can't do that with? :mug:

Here's the article I keep referring to: http://www.howtobrew.com/appendices/appendixD-2.html

Basically to me this is about 2 things:

1. Better distribution of collection points leading to higher efficiency (although well executed double batch sparges can get great efficiency even with just a single braid as has been proven.

2. Larger surface area for wort to drain into lowering the chances of a stuck sparge... even if the center piece became clogged and stuck you'd still have the ring, etc.
 
Also keep in mind the path of least resistance is always going to be inside the braid, the wort there can flow freely without any restriction from the grain bed.

Ahh...not really. I like the reasoning that the wort inside the braid will flow freely, but in order for it to flow, new wort must flow through the grain bed and enter the braid. I would guess that unless you drain very slowly, the bulk of the wort enters within the first few inches of the braid as it is very porous.
 
Ahh...not really. I like the reasoning that the wort inside the braid will flow freely, but in order for it to flow, new wort must flow through the grain bed and enter the braid. I would guess that unless you drain very slowly, the bulk of the wort enters within the first few inches of the braid as it is very porous.

It's possible I'm wrong but I'm not sure this is the case, here's my reasoning...

As soon as you open the drain anything in the line is going to be the fastest thing to flow out the drain, as there is next to no flow restriction within the line (by line I mean the braid). Any point inside that braid that isn't full of wort is going to be a void, at that point the wort outside the braid is going to want to fill that void, regardless of where it is. We are talking about a limited volume that can pass through any point in that braid so I think as long as your flow is enough to keep the full tube somewhat drained constantly you're going to get good flow through all parts of the tube.

That's my thinking anyway, obviously there is plenty of calculations around this that could be done to determine optimal flow rate based on braid volume, surface area and porousness but in general if there is a void in the braid wort will flow into it. Same principle for any other MLT using copper or cpvc with slits cut in it really, as long as you create a void wort should flow into it, the trick is making sure that you are draining at the right speed for your particular setup I would think....

Again, I could be wrong but it seems logical. Once I get something setup I will try draining some water with drops of food coloring in different places that should at least give some indication as to what's going on, it won't be exact without a grain bed but it should be good enough for testing theories here. If I'm feeling ambitious maybe I'll video it and post it here.

Man I'm over thinking this....
 
TheYoshi,

Did you ever do any tests with this? I am building a round cooler MLT and came to the same conclusion as you about the braid construction.
 
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