custom gaskets

[NeverDie]

I now have a number of glass carboys that lack a good enough lid seal to support an airlock. The CO2 fermentation gas simply leaks around the lid seal instead of going through the airlock.

So, I'm thinking of making my own custom gaskets to provide an adequate lid seal. I figure that the lid can be used for compressing the seal against both the lid and the glass rim of the carboy.

So far, the gasket material I've found which appears to hold the most promise is: https://www.amazon.com/gp/product/B01NAG4I3J/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
It claims to be "food grade." I would have to cut it rather carefully to fit the lid.

Anyone else here making their own custom gaskets? If so, what gasket material are you using?

 

[Blacksmith1]

I just use drilled tapered plugs. I don't see how they could not work, unless the inside of the carboy neck is damaged.

 

[Maylar]

Do the lids screw on? How big are they?

 

[NeverDie]

Do the lids screw on? How big are they?

The 5 gallon glass carboy has a screw on lid (but no gasket).
https://www.austinhomebrew.com/5-Gallon-Glass-Wide-Mouth-Carboy_p_7990.html
I had thought that I could seal around it using masking tape, but that didn't work at all.

The demijohn lid is 5 inches wide and is not screw on.
https://www.morebeer.com/products/glass-demijohn-4-15-wide-mouth-plastic-basket-1.html?site_id=9
It came with a plastic lid that sorta snaps on, but it's not airtight. I haven't yet tried taping this one, but I'm now starting to doubt whether that will work. With no screw to provide compression for a gasket, this one might be difficult. One embryonic idea: maybe I could use a dumbell weight to apply gravity pressure around the perimeter with an airlock sticking up through the center of the weight. In that scenario perhaps a gasket might work, because the dumbell weight would be supplying the compression.

 

[NeverDie]

I just use drilled tapered plugs. I don't see how they could not work, unless the inside of the carboy neck is damaged.

Do there exist tapered plugs with diameters of 5 inches and 5.5 inches? My LHBS doesn't carry anything like that.

 

[Maylar]

Hmm. I have one of the big mouth fermenters that has a screw on lid, and there are replacement gaskets: https://www.northernbrewer.com/products/extra-lid-gaskets-5-count
I'd say they're about 5 inches, maybe 6. Cheap enough to try.

The one I have without a screw cap has a push-in cap with rubber "fingers" and it needs tape to keep it from popping out.

 

[Maylar]

Do there exist tapered plugs with diameters of 5 inches and 5.5 inches? My LHBS doesn't carry anything like that.

Check Northern Brewer's Big Mouth product line.

 

[parjay]

https://www.mcmaster.com/o-rings

Just measure inner diameter, outer diameter, and thickness.

 

[Blacksmith1]

Do there exist tapered plugs with diameters of 5 inches and 5.5 inches? My LHBS doesn't carry anything like that.

i don't think mine does either. You didn't mention that you could fit a small dog into the fermenter....

 

[CKuhns]

I use regular cling wrap. After you get your lid or cap on tight as you can wrap it real tight with that clear cling wrap you have in the kitchen. Works pretty well.

 

[NeverDie]

Hmm. I have one of the big mouth fermenters that has a screw on lid, and there are replacement gaskets: https://www.northernbrewer.com/products/extra-lid-gaskets-5-count
I'd say they're about 5 inches, maybe 6. Cheap enough to try.

Thanks! That's a great looking find at a really good price. I ordered it yesterday, but it won't arrive until Thursday. So, between now and then I'll try CKuhns's cling wrap method.

Bravo to both of you!

 

[NeverDie]

Reporting back: I tried Costco's stretch-tite wrap, but it was a fail. I'll next procure some actual Glad cling-wrap and try that. IIRC, Glad cling-wrap has a thicker gauge to it, and so maybe it will make a better seal against the lid.

 

[Blacksmith1]

I used glad as a 24 hr airlock by putting a pinprick in it. Worked till i could go get an extra drilled bung. Good stuff.

 

[NeverDie]

Reporting back: I tried Glad cling wrap, Glad Press and Seal, and also Saran wrap. All were fails at getting enough of an airtight seal with the plastic cap that was holding my airlock. I'll try again with the Big Mouth gasket when it arrives on Thursday. I suspect the plastic cap is pretty much garbage for this application.

Meanwhile, I set the lid aside, made a seal with just the Saran Wrap and pricked a tiny pinhole into it, I guess similar to what Blacksmith1 did above. This is the stopgap until Thursday. It seems to be working with positive pressure, because the saran wrap is puffed up into a domelike shape. The current SG is 1.014, so for now there's enough fermentation going on to maintain adequate positive pressure. Hopefully the positive pressure will maintain between now and Thursday.

 

[Yooper]

I don't understand what you're trying to do- you can't find the proper size bung for your carboy?

 

[Yooper]

Oh, never mind- I see the problem. You're trying to use a wide mouth carboy for mead?
Even if you get a better seal, the headspace is still pretty darn wide and I wouldn't risk it.

 

[NeverDie]

Oh, never mind- I see the problem. You're trying to use a wide mouth carboy for mead?
Even if you get a better seal, the headspace is still pretty darn wide and I wouldn't risk it.

Are you saying too much headspace is a concern during the fermentation phase? I thought I had read somewhere that it was only a concern during secondary aging.

I had wanted to use a wide mouth glass carboy for fermentation because it's easier to reach inside and clean it. But if I can't find a proper bung for it, with an airtight seal, I may have to abandon that in favor of a narrower mouth for which bungs are much more available. Either that or go plastic, which I'd rather not do.

 

[Blacksmith1]

That's why I have 2 large buckets. An 8 gallon and a 6.5

 

[NeverDie]

Do the lids that come with the wide mouth Big Mouth Bubbler glass carboys have a good airtight seal on them? I think I had read that the out-of-the-box lid was garbage, but that Northern Brewer had some kind of fix for it that made it useable for airlock purposes. All of this may be obsolete dated information though. Maybe the current offering is different.

 

[BruceH]

I now have a number of glass carboys that lack a good enough lid seal to support an airlock. The CO2 fermentation gas simply leaks around the lid seal instead of going through the airlock.

So, I'm thinking of making my own custom gaskets to provide an adequate lid seal. I figure that the lid can be used for compressing the seal against both the lid and the glass rim of the carboy.

So far, the gasket material I've found which appears to hold the most promise is: https://www.amazon.com/gp/product/B01NAG4I3J/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
It claims to be "food grade." I would have to cut it rather carefully to fit the lid.

Anyone else here making their own custom gaskets? If so, what gasket material are you using?

Have you considered using wax? If I understand correctly there is a lid but it just isn't airtight. Is that the deal?

 

[NeverDie]

Have you considered using wax? If I understand correctly there is a lid but it just isn't airtight. Is that the deal?

That's the deal. How would I use wax? Do I melt it and drip it around around the edges to seal it?

 

[NeverDie]

Or maybe when the plastic wrap airlocks lose positive pressure, I should then simply rack these larger batches into 1 gallon jugs for aging so that there's no headspace issues? Is that the better way?

I honestly hadn't thought that finding large enough bungs would be a problem. If I had known that it would be, then I wouldn't have purchased these supper wide mouth vessels.

 

[NeverDie]

It turns out my wife has an adjustable circle cutter, so I ordered this:
https://smile.amazon.com/gp/product/B0075DZFA0/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
to make a custom gasket for the 5 gallon carboy which has the seemingly lousy plastic lid. If it turns out that a 1/8" thick gasket isn't enough to seal the lid under compression, then I may punt and buy a different carboy.

 

[Blacksmith1]

Are you sure the airlock is making a seal?

 

[NeverDie]

Are you sure the airlock is making a seal?

AFAIK.

 

[NeverDie]

It turns out my wife has an adjustable circle cutter, so I ordered this:
https://smile.amazon.com/gp/product/B0075DZFA0/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
to make a custom gasket for the 5 gallon carboy which has the seemingly lousy plastic lid. If it turns out that a 1/8" thick gasket isn't enough to seal the lid under compression, then I may punt and buy a different carboy.

Reporting back: it worked. It was too thick for the circle cutter to cut through, so really a simple compass would have been good enough for marking out the cut line.

The material itself wasn't as spongy as I thought it would be. If I were to order more flat sheet gasket material, I would try to purchase something a bit more squishy.