Home made mash tun keeps blocking

[Pwntang]

Hi everyone,

After looking at lots of different ways to do it, I decided to make my own mash tun using a Thermos cooler and a copper manifold with slots cut in to allow for drainage.

I had the opportunity to use it for the first time today, but it hasn't gone well at all!

I let the grain mash for an hour then started the run offs but within a couple I lost the flow completely. Fortunately the way it's built has allowed me to use a mash paddle to push the copper ring out of its housing and now the wort is flowing out of the tap but VERY slowly and I think it will stop very soon.

I've been sat here for 30 minutes and not even 5 litres has come out! I think I have ruined this brew now!

Can anyone make any suggestions to me please? Have I cut the slots too big, too small, not enough of them?? Has anyone else had a similar experience?

Once the tun is empty I can take some photos of what it looks like.

Thank you in advance.

 

[Ohio-Ed]

Some photos, some description of what you were mashing, and water/grain ratio would help.

Ed

 

[buzzkill]

did you start the run off slow or just open it up?

 

[lostboysbrew]

Sounds like one of 2 things.......either you opened it up too quick and got it clogged, or based on what the mash was, perhaps got a stuck mash.........

+1 to Ohio-Ed, photos, and mash (grain/water ratio) would be helpful........

The lautering of your mash should take almost an hour, SLOW draining.....if you opened to fast, it probably clogged, more infor will help..........

 

[Revvy]

Are you using a hose at the end of the spigot? THat is the number issue I have found with people using their mash tuns for the first time. No hose on end of spigot. You still need to have a siphon to help draw out your wort, and a hose does that by lowering the level of your out hole.

Next thing would be to make sure the manifold slots are wide enough to get flow but not too wide to let grain particles get to the ball valve and block it. Thirdly make sure there are no pieces of copper that got knocked from inside the manifold to the ball valve and could be blocking that.

These tend to be the most common issues with the first test or usage. Sometimes initially it is purely mechanical and often a simple blockage or lack of siphon.

 

[malkore]

The lautering of your mash should take almost an hour, SLOW draining.....if you opened to fast, it probably clogged, more infor will help..........

assuming he's fly sparging. if he batch sparges you drain as fast as the system allows.

My vote: a $4 stainless steel braid swapped for the manifold. mine NEVER gets clogged up.

 

[Bobby_M]

It also sounds like you have the slots facing up. The slots should be hacksaw blade thin spaced about 5mm apart, going about half way through your copper tubing. The slots face down. Also, as mentioned, you need tubing on the output.

 

[Pwntang]

Hi,

Thanks to everyone that replied. I can confirm:

1. I was mashing 3.7kg Pale Malt, 300g Crystal Malt, 300g Wheat Malt with 12 litres of water
2. I opened the tap all the way
3. I was not using a tube on the end of the tap
4. The slots were cut with a dremel disk and I had them pointing up
5. I was going to use batch sparging, but I failed on the first run off.

I've just about finished cleaning up so I'll take some pictures of my mash tun and post them here.

It looks like there were perhaps several reasons for my failure that have been identified here.

 

[Revvy]

Hi,
3. I was not using a tube on the end of the tap.

FTW...This is more than likely the cause of it. Like I said before it is the most common new mashtun user issue on here.

 

[Pwntang]

Hi Guys,

Here are some pictures of my tun as requested. Apologies for the delay, I have been working away from home all week.

http://img227.imageshack.us/img227/8431/dsc02941w.jpg
http://img602.imageshack.us/img602/5906/dsc02939.jpg
http://img219.imageshack.us/img219/7/dsc02938w.jpg
http://img819.imageshack.us/img819/6350/dsc02937p.jpg

In response to advice here I have purchased some reinforced PVC tubing to use when I try again and I will not open the tap too much. I'll also put the slots downwards instead of upwards next time.

 

[Sawdustguy]

I would cut a chitload more slots in that manifold if I were you.

 

[Ohio-Ed]

Hi Guys,

Here are some pictures of my tun as requested. Apologies for the delay, I have been working away from home all week.

http://img227.imageshack.us/img227/8431/dsc02941w.jpg
http://img602.imageshack.us/img602/5906/dsc02939.jpg
http://img219.imageshack.us/img219/7/dsc02938w.jpg
http://img819.imageshack.us/img819/6350/dsc02937p.jpg

In response to advice here I have purchased some reinforced PVC tubing to use when I try again and I will not open the tap too much. I'll also put the slots downwards instead of upwards next time.

In my opinion, you need WAY more slots cut. Probably at least 2 between each you have cut now. And they could probably be a bit wider.

Put the slots facing down.

It looks like I can see some burrs on the inside of the tube where you cut the slots. Ideally, you would clean up the inside of your tubes to remove any loose debris.

As suggested earlier, a hose on the output of your valve should allow you to siphon down until air is sucked into the slots.

Good luck,
Ed

 

[boo boo]

Having the slots face up had to be his problem as well as opening the valve and letting it go full out. I batch sparge and will vourlaf with the valve partly open until I establish a good flow at which time I then gradually open the valve full.
When draining the tun I also do it slow at first.

 

[Pwntang]

More slots, got it.

I'll do exactly that before I try and use it again.

 

[Catt22]

More and deeper slots.

 

[BigBadMikey]

Ditto on cutting more slots. I used my bandsaw to cut a slot every 1/4" in my manifold. I made sure to cut the slot 1/2 way through by using a stop block on my bandsaw table. Took no time at all. I have had no stuck mashes, and I typically do not use a tube to add siphon, but I will try that next time I brew...

 

[DeafSmith]

Another suggestion, though this one isn't the cause of your blockage - it's hard to tell from the picture, but in the third picture it looks like you may have the left end of the manifold elevated in order to connect to the outlet. If the entire manifold is not lying flat on the bottom of the cooler, drainage will stop as soon as the wort level gets to the slots on the elevated end, allowing air to enter. You want to keep all the slots as low as possible because the dead space will be determined by the point at which air is first able to enter the manifold. The manifold should be flat on the bottom and use either an elbow, a bent copper tube, or a flexible silicon tube if needed to connect to the outlet. This will keep dead space to a minimum. It also helps during the last part of the draining to keep the end of the tube on the output under the surface of the wort in the kettle to keep air from entering from the outside end and possibly stopping the siphon.