Airlock Hole Diameter

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cliffo

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Hey Guys,

I bought a couple of the 25L drums from Bunnings and have to drill a hole to fit the grommet. Can anyone tell me what size the hole should be to fit the grommet snugly?

Cheers,
cliffo
 
I think you'll be safe with 1/2" (13mm) holes, this seems to be the norm. The grommets do vary though.

FWIW Grain and Grape have some larger 3-piece airlocks, made from a softer translucent plastic and having a tapered tube, so I've been using these pushed into the hole with no grommet. A lot less messing around. You'll need a larger hole (16mm).

Another option is to use a drilled rubber bung in a 1" (26mm) hole.

Grommets suck.

:super:
 
Oh, and if you are going to use a grommet try to avoid putting it in the lowest point in the middle of the lid - any liquid that collects in the lid (eg condensation, spills etc) will try to seep through the hole and into your brew. I don't think grommets seal very well.
 
Clifffo

12mm is the correct size for an airtight fit.

Cheers
 
vin said:
Clifffo

12mm is the correct size for an airtight fit.

Cheers
[post="93441"][/post]​


Spot on, 12mm. The lid of one of my 32L plastic fermenters has a 13mm airlock hole. Have to use the two piece airlocks with it as the S bend type will not seal properly (they have a slightly smaller OD tube). Mistakenly drilled 13mm holes in the caps of some of my 2L starter bottle caps (missed by 1mm) and have the same problem with them.
 
Thanks guys...off to Bunnings I go.... :)

cliffo
 
Wortgames said:
Another option is to use a drilled rubber bung in a 1" (26mm) hole.



:super:
[post="93424"][/post]​

hi wortgames,

this sounds like a good idea, have you used it without any problems ?

cheers
yard
 
I have seen airlocks with rubber on the bottom, gets rid of the grommet and gives you an airtight seal in a 12mm hole.

Can't remember where I saw them though..
 
yard glass said:
Wortgames said:
Another option is to use a drilled rubber bung in a 1" (26mm) hole.
[post="93424"][/post]​
this sounds like a good idea, have you used it without any problems ?
[post="93560"][/post]​

Hi Yard Glass,

I've used it in demijohns plenty of times. I haven't tried it in a plastic lid but I can't see why it wouldn't work.

Here's someone using it in a converted keg fermenter:

kegferm.jpg

:beer: WG
 
Bought two of these barrels today wondering how did you make the hole did you drill it or did you use a wad punch? Don't want to split the lid... Thoughts?
 
You do realise this thread is ten years old?
As mentioned above, drill it out. Be sure to place a bit of wood under it to prevent cracking.
Or ditch the plastic lid for gladwrap. Just use the lids o ring to hold it in place.
 
No I didn't realize it was that old OK thanks will drtill it.
 
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