Hello!
I'm having trouble sealing a drain valve on my keg, I know you can't use silicone in distilling as it can leach nasties into the product. But can you use Sikaflex 221 100% polyurethane
DESCRIPTION
(from their data sheet: Sikaflex®-221 is a high-quality multi-purpose 1-component polyurethane adhesive / sealant)
CHEMICAL RESISTANCE Sikaflex®-221
is generally resistant to fresh water, seawater, diluted acids and diluted caustic solutions; temporarily resistant to fuels, mineral oils, vegetable and animal fats and oils; not resistant to organic acids, glycolic alcohol, concentrated mineral acids and caustic solutions or solvents.
Oh I hate these questions.
I really feel you should be addressing the reason your drain is leaking .
Got some photos or explanation where and why it’s leaking ?
I’m sure a real fix is better than applying a bandaid in a tube .
Maybe 10% abv wash isn’t going to be a problem , maybe 30-40% low wines will be .
muse wrote: ↑Tue Feb 13, 2024 2:54 am
CHEMICAL RESISTANCE Sikaflex®-221
is generally resistant to fresh water, seawater, diluted acids and diluted caustic solutions; temporarily resistant to fuels, mineral oils, vegetable and animal fats and oils; not resistant to organic acids, glycolic alcohol, concentrated mineral acids and caustic solutions or solvents.
Besides ethanol, fermentation produces lots of organic acids. Better to avoid it altogether IMO.
Basically the hole is slightly too large and the solder doesn't fuse the gap it just runs away from the gap. Can you use copper wire or some method to provide a packing to allow the solder to sit?
Harris makes a solder that's supposed to work better for loose fits and gaps. Last i looked it was less $ than Stay Brite 8. Be sure to use a good stainless steel flux (e.g. Stay Clean).
Swedish Pride wrote: ↑Tue Feb 13, 2024 10:59 am
Copper wire may work, it's a bit finicky.
Cut a copper disk slightly larger than the hole, solder that on your drain and then solder the whole assembly over the hole.
Using silver solder on the disk/ drain and normal leadfree on the hole will make it easier but it should all be doable with leadfree if you're patient
Yep, that's what I'd do too.
But I'd tin up the disk and the mating face, then the same with the drain assembly, then when you heat it all up both solder joints will flow at the same time.
Also much easier if you can drill through the drain stub after soldering, so you've got no issues with centering the disk up.
muse wrote: ↑Tue Feb 13, 2024 10:02 am
Thanks guys, I'll avoid.. Damn haha.
Basically the hole is slightly too large and the solder doesn't fuse the gap it just runs away from the gap. Can you use copper wire or some method to provide a packing to allow the solder to sit?
Thanks everyone. I avoided any silicone, adhesives and managed to make a copper ring out of fine wire flux it up and insert over the 15mm shotgun pipes. This allowed me to bridge the gaps with solder drips.
Leak tested and great!
Onto the next problem, my flux is useless for stainless, I've ordered some strong stainless flux. Hard to find on shelves in the UK!
When I first joined way long ago, I had a book called The lore of Still building, and the nix was the best of them, Ive seen a bit on here about them. also, why that tube that goes from the bottom of the cup back to the reflux tube ? and why needled valves ? How do they stak up against a bokabob if ...... " head to head " does a new still beat them ?
When I first joined way long ago, I had a book called The lore of Still building, and the nix was the best of them, Ive seen a bit on here about them. also, why that tube that goes from the bottom of the cup back to the reflux tube ? and why needled valves ? How do they stak up against a bokabob if ...... " head to head " does a new still beat them ?
