How To Patch Hole In Cooler Mash Tun?

[notung]

Hello all,

Well I'm glad I've got a sense of humour, because I've buggered up my Keep Cold mash tun a bit... Yesterday I installed a large-dial mashmaster mkii thermometer, which involved cutting a 19mm diameter hole with the hole saw. I think I mustn't have been thinking very straight, because I drilled just a short distance above the tap, coming out on the inside right next to indent (pictured). Anyway, this didn't leave enough room at all for the washers & nut to attach.

Anyway, I have installed the thermometer in a far wiser position with no problems, but this does not fix the fact that I have a suddenly leaky mash tun!!! I am looking for inspired ideas on how to patch up the hole (which is smaller than 19mm on the inside). So far I have thought of cutting a piece of silicone/flexible plastic to size and gluing down with selleys silicone sealer. I wondered if I could fill the interior with some of that expanding foam stuff, so no heat was lost either...

Does anybody have a better idea than this? I wondered if there was some sort of patch kit that you could get for plastic containers like this? If anybody knows of something that would suit, please let me know!! Below are pictures of the exterior, and interior. There is the taphole obviously, then above that is my mistake.

Cheers

 

[Supra-Jim]

Try your local plumbing supplies shop for a 3/4" threaded plug and matching nut. Push the plug through the hole and then tighten the nut on the inside of the esky. Maybe use some silicon washers/orings to help ensure it is leak tight.

 

[kram]

According to Ross' post 'Selleys Knead It' is food safe.

 

[Swinging Beef]

bung in a bung!

 

[trevc]

A threaded plug with a bunch of Teflon tape might be good for sealing it up.

Also, I found that the washer on my MM was leaking no matter what I did. I replaced it with a slightly larger silicon one.

 

[Doogiechap]

Also, I found that the washer on my MM was leaking no matter what I did. I replaced it with a slightly larger silicon one.

In fact you will get leaks fairly easily between the internal nut and the washer. You are better off ditching the internal washer and thread sealing the internal nut and just using the silicone washer and then using the external nut to tighten the assembly so the internal silicone washer isn't deformed.
Well this makes sense in my head anyway.
:blink:

 

[trevc]

Good point Doogiechap. I learned this the hard way by over-tightening, and ripping the inside silicon washer.

I find the MM washers too small, and too rigid to give a good seal. You can generally make a better one by ripping apart silicon kitchen accessories.

 

[buttersd70]

I agree with beef, a solid rubber bung. Heat the bung in boiling water so its as soft as its going to get, jam it in super tight. The bungs are pretty good, i use one with a hole for my outlet with no leaking around the edges.

 

[FarsideOfCrazy]

I agree with trying block it up with an assembly of some description as that type of polythene plastic can have adhesion issues if you try to use a glue of some sort of description.

 

[notung]

that type of polythene plastic can have adhesion issues if you try to use a glue of some sort of description.

Thanks for the suggestions everyone. I have looked into threaded plugs at Reece's but the things just have to short a thread! These cooler walls are pretty thick! The bung idea could be a real goer, and economical too... As another idea, I have wondered about engaging the services of a plastic welder. I am going to drop by today with the mashtun for a quote.

Thanks for the warning about adhesion issues BG. Do you know if the famed Selleys Knead It - Aqua would be up to the task? Sounds like nice stuff...

What an expensive mistake - everyone should take their drilling very seriously!

 

[crozdog]

you could always use a piece of nylon (aka white breadboard available from $2 shops) glued over the inside holw with aquarium silicone. I used this technique on my old esky type tun & had no issues.

 

[afromaiko]

Thanks for the suggestions everyone. I have looked into threaded plugs at Reece's but the things just have to short a thread! These cooler walls are pretty thick! The bung idea could be a real goer, and economical too... As another idea, I have wondered about engaging the services of a plastic welder. I am going to drop by today with the mashtun for a quote.

Thanks for the warning about adhesion issues BG. Do you know if the famed Selleys Knead It - Aqua would be up to the task? Sounds like nice stuff...

What an expensive mistake - everyone should take their drilling very seriously!

Use a standard bung with a small hole up the middle. Jam it into the hole from inside.

Then a bolt going out through the bung to a nut and washer on the outside. Done up tight should seal well.

Use a wide headed bolt if you can. If you need to also put a washer on the inside to stop the bolt head pulling through then cut up a silicone backing tray to make a tight fitting washer to sit between the metal washer and bolt head.

Stainless bolts, washers etc can be found at Bunnings.

 

[notung]

Good morning,

I thought I would post some pics of my patch job on the mash/lauter tun. I ended up using a whole lot of Selleys Knead It Aqua, and cut a bit off a silicone baking sheet for an extra seal. I put the knead it right over the top of the silicone layer however, and it has formed a bond with the plastic.

Also a chance for me to show my braided hose setup. These bits of drinking water hose will help to pick up from the bottom of the tun, as I found I was leaving a bit behind with the hosebraid hooked directly up to the brass T. What do you think?

Thank you for your help!

 

[yardy]

tested it with the heat yet ?

 

[FarsideOfCrazy]

tested it with the heat yet ?

Yeah I'd do a run with just water before you go and put a brew in it, other wise spillage might occur which is very bad.

 

[MaestroMatt]

Sorry to resurrect an old topic but the same thing has just happening to me in almost the same circumstances.

Just want to know if the Selleys knead it aqua stuff is still the best options for trying to repair a hole in an esky.

I need to repair a hole I made due to installation of the temp probe much too high up on the tun.

Any help would be great!

 

[notung]

MaestroMatt,

Doesn't it drive you to despair!

I can tell you how it went with my mash tun if that helps. Basically the Selleys Knead It 'Aqua' stuff that I tried was pretty inadequate! It just did not adhere to the plastic effectively enough to keep a reliable seal. In the end I ended up plugging the hole with Knead It as you can see in the pics above. I then used a piece of Reject Shop silicone baking mat, cut into a little square and glued on to further patch up the interior side of the hole. I attached this with aquarium grade silicone. This has given me no leaks and I am happy with the seal.

For future mash tuns, I really don't think I would mount a dial thermometer. For their iffy accuracy, I would probably satisfy myself with a little digital stick one.

Hope this helps. If there's any other advice I can give, let me know.