Can you link us to those directions? That's not a common mash tun drain installation. I doubt that bung is going to stay put and seal well, it may loosen up or even drop out at some very inopportune time...
Here's a collection of bulkhead fittings:
https://www.bargainfittings.com/index.php?route=product/category&path=47
@Bobby_M from BrewHardware.com also has a variety of bulkhead fittings
but I can't seem to find them on his site listed here:
https://www.brewhardware.com/SearchResults.asp?Search=bulkhead&Submit=Although I'm not familiar with
your tun output spigot, you probably want something that resembles these:
https://www.brewhardware.com/product_p/truebulkheadmale.htmor
https://www.brewhardware.com/product_p/vb2.htmA stainless 2-piece valve would typically go on the outside.
The mash tun side of a stainless bulkhead is visible in the pictures in this post:
https://www.homebrewtalk.com/threads/how-long-can-a-starter-last.703882/post-9339220You don't need the whole manifold I built, just anything that can keep the grain in tun while letting the wort run out will work fine, such as a braided hose, Bazooka tube, copper pipe with slots or drilled holes, etc.
Here is what I used and where I found it. The guy who wrote it up, Denny, is a member of the American Homebrewers Association. They have a forum that I am part of as well. Great info there too. I go between here and there just to get as many opinions as I can. His Website is Dennybrew.com. He has been a really great provider of info for me. If this doesn't work, then I will look into what you posted. But for now, I have all the items and am going to give it a go. I bought everything I needed except the cooler on amazon for about 20 bucks. I found the cooler for 20 bucks used, so my output here has been about 50 bucks all told. I have a couple of extra bungs and valves just in case. Also, I used the food grade silicon. I found that when I adjusted the hose where it went thru it leaked just a small amount. I am going to run a bead around the hose where it goes thru the bung as well, that dropped a few drops of water too. But nothing significant. Rock on!!!!!
I apologise up front if using the following instructions from his website is a violation of any rule or policy of the forum. Please feel free to remove it and the web address if that is what is right.
Building the Mashtun
For the mashtun, you’ll need a cooler. I prefer the rectangular ones. The large top opening makes it easier to stir the mash than a round cooler does. Since grain bed depth makes practically no difference in batch sparging, one of the main reasons people use the round coolers is nullified. The rectangular ones are also cheaper. You’ll also need a rubber bung for a minikeg, some 1/2 inch ODx3/8 inch ID food grade vinyl tubing long enough to reach from whatever you set your cooler on to the bottom of your kettle PLUS 6 inches, an inline nylon valve, and a length of water supply line with a stainless steel braid for a jacket, and 3 hose clamps. The length of the water supply line doesn’t really matter. I use one that’s long enough to run the length of the cooler, but my experiments have shown that shorter ones seem to work as well. Feel free to substitute parts if you’d like something a little snazzier. The only really crucial piece of the whole setup is the stainless hose braid, so if you want to put a fancy ball valve or something else on your mashtun, go for it!
NOTE: The minikeg bung fits snugly into the hole left from removing the drain in most of the 48-54 qt. coolers I’ve checked. If the fit is loose, or you’re worried about leakage, apply some food grade silicone sealant on the flange before inserting the bung into the cooler. Be creative!
Step by Step
1.) Remove the spigot from the cooler. Usually, there’s a nut on the inside of the cooler holding the spigot on. Unscrew that and the spigot should pop right out.
2.) Remove the plastic insert from the hole in the minikeg bung, and insert the bung into the spigot hole, from the inside of the cooler. The beveled edge of the bung goes in first, and the flange of the bung should end up flush with the cooler wall.
3.) Cut off a 6 inch piece of the vinyl tubing and, from the inside of the cooler, insert it into the hole in the minikeg bung. Let a couple inches of tubing protrude from each side of the cooler.
4.) Cut the threaded fittings off the water supply line (I use a hatchet). Pull the tubing out from the braid, leaving you with a hollow length of hose braid. Flatten the last inch or so of one end of the braid. Fold it over on itself 3 times to seal the end. Squeeze the fold with a pair of pliers to crimp it closed.
5.) Slip a hose clamp over the end of the braid, and slip the braid over the end of the vinyl tubing INSIDE the cooler. Tighten the clamp until snug, but don’t squeeze the tubing shut! photos 2nd row #2 and #3
6.) Insert one end of the valve into the tubing on the outside of the cooler and secure it with a hose clamp. Slip another hose clamp over the end of the long piece of tubing, connect the tubing to the output side of the valve, and secure with the hose clamp.
That’s it! You’ve built your Cheap ‘n’ Easy mash/lauter tun! Now, let’s brew some beer!