Help getting seal on stainless steel fusti

[Kepler]

Hi all,

So I've been using a stainless steel fusti (Sansone model) as my fermenter. It works great, nice internal welds, easy to clean etc etc.

The lid screws down and has a rubber gasket to form a seal. Only thing is it doesn't seem to hold a completely airtight seal. I've tested it lots and under any kind of minimal pressure (eg. blowing air through the spigot opening) air leaks out from the seal.

I know a lot of people don't feel a completely airtight seal is necessary for a fermenter. And I'm fine with that. But I wanted to try doing a pressure transfer from the fusti - so wanted to have it seal properly.

I purchased a fatter silicone oring (that is perhaps slightly too large diameter) but this didn't help.

Pictures attached. Any ideas?

 

[day_trippr]

I bet that would work better with an O-ring that would seat inside the lid at the top...

 

[Kepler]

I bet that would work better with an O-ring that would seat inside the lid at the top...

Thanks, do you mean a smaller diameter o-ring or a thinner one? Or both?

 

[day_trippr]

Smaller overall diameter, certainly. Not sure about the thickness, you'd have to judge that one for yourself.

It appears the gasket you tried goes around the neck of the fusti, while I think if you found a gasket that would stuff up inside the lid with a good fit it might seal tight...

Cheers!

 

[OleBrewing]

not sure how those threads hold up on the lid, but looks like you are on the right track maybe use a flat seal.

or for simple wrap it with electricians tape.

 

[MaryB]

I would get a flat seal(or cut one myself) from silicone rubber so that it friction fits inside the lid. Go with whatever thickness is needed to make it seal. Put some plumbers putty inside the lid in one spot and screw it down then measure how thick it is once flattened on the rim. Double that for your gasket thickness.

 

[Kepler]

I would get a flat seal(or cut one myself) from silicone rubber so that it friction fits inside the lid. Go with whatever thickness is needed to make it seal. Put some plumbers putty inside the lid in one spot and screw it down then measure how thick it is once flattened on the rim. Double that for your gasket thickness.

Thanks MaryB. I think that's what the original seal that came with the fusti is trying to do. If you look at the pics I uploaded there is one with the original white seal in place (on the lid that is upside down). Were you suggesting something different?

 

[MaryB]

That seal is outside the lid, I would put it inside so it sits on top of the jar threaded section.

 

[day_trippr]

Ahh...I have a feeling that we're being misled by the pictures.
I've been assuming that the lid screws OVER the fusti neck, but I'm beginning to believe that isn't the case and the lid threads to the INSIDE of the neck.

If that's the case then the white gasket as shown seems properly installed and would likely perform better than the red silicone O-ring. Perhaps the problem is the lid isn't being screwed down tight enough to squish the gasket...

Cheers!

 

[Kepler]

Ahh...I have a feeling that we're being misled by the pictures.
I've been assuming that the lid screws OVER the fusti neck, but I'm beginning to believe that isn't the case and the lid threads to the INSIDE of the neck.

If that's the case then the white gasket as shown seems properly installed and would likely perform better than the red silicone O-ring. Perhaps the problem is the lid isn't being screwed down tight enough to squish the gasket...

Cheers!

Sorry about that! Yes the lid threads inside the neck of the container. I can see how those pictures might be confusing! I have the lid sitting upside down on top of the container in most of those pictures.

I might still try and get a smaller o-ring that fits inside the neck of the container, or failing that a thicker gasket (although these seem harder to come by...)

 

[Kepler]

Dammit! So I've tried various sized and thickness orings and this thing still wont seal properly.

Does anyone have any other ideas (I really want this to work)? Or am I flogging a dead horse...

 

[Stealthcruiser]

Without doing a visual in person, I can't offer much.

The flat seal that came with it:
With the lid screwed on, sans the seal, how much gap between the two surfaces to be sealed?

Then how thick is the seal?

Thicker than the measured gap?

If so, when installing seal and lid, wet all liberally with alcohol, as it makes rubber and silicone rubber slick, and "should" allow the seal to "squish" a little more uniformly, without it extruding from between the lid and the jar.

Snug, mind you.......Not gonzo torque on it!

Good luck!