Dear Mr. Wizard,
I recently have acquired a keg from a buddy at work. I’m not sure where he got it, but I was wondering if I should pay a welder to cut the top off the keg or if I can do it myself? Also, to add a spigot, does that have to be welded on the keg or could I use something else instead of welding?
Sterling Heights, Michigan
Mr. Wizard Responds:
Jeremy, this sort of question comes about once a year and when I answer I always “beat up” the questioner . . . so I hope you’re a good sport! Okay, just so I understand, your buddy at work found a “stray keg” that was abandoned at a party or behind some skanky bar and gave this keg a nice warm home in his basement. Now the keg has been donated to you since you are a homebrewer and can put this sad and lonely keg to good use. Is this a decent re-creation of the facts of how you got this keg?
The true owner of the keg does not really care where your friend got this keg. The owners really just want their property returned. Most keg owners do not camouflage their identity to confuse prospective keg users with questions about who really owns the keg, rather they stamp the brewery name on the perimeter of the top (called the chime). Sometimes they even paint their name on the side of the keg. Boulevard Brewing Company in Kansas City, Missouri, has clever stickers on their kegs asking customers to help return lost kegs to the brewery. These stickers also comically explain that keeping one of their kegs is theft.
The reality of kegs is that some are damaged to the point where they can no longer be used and are actually retired. For those readers interested in buying used kegs, start with your local craft brewer. This is a legal way of acquiring property. Many brewers, especially the larger guys who don’t sell their used stuff to individuals, sell used kegs to companies like Sabco (www.kegs.com) who recondition and resell them. Reconditioned kegs typically have the original owner’s name ground off of the chime, especially if they are resold to another brewery. Sabco even sells the parts required to convert a keg into a kettle, and actual keg-kettles.
This is the end of the prelude to the answer to your question and that is about paying someone to do the work versus doing it yourself. I know a lot of folks who work on stainless steel and not one of them would dream of paying someone to do something that they can do themselves. The fact that you ask about attempting this yourself leads me to believe that you have no experience cutting or welding stainless steel.
My recommendation on this project is to have someone do the work for you if you have never done this before. Or, at very least, have someone that does have experience help you do the work. If possible, I would cut off the top with a plasma torch for the smoothest cut that would require a minimal amount of grinding to remove burs and irregularities in the shape.
As far as outlet fittings, you can go with a welded outlet or a bulkhead fitting. A bulkhead fitting is inserted in a hole and sealed with a gasket and nut. The advantage of this style fitting is that it requires no welding and is easy to replace. The disadvantage is that the gasket and nut present a crevice on the inside of the kettle and is not as easy to clean as a smooth, welded connection. I prefer welded fittings for this reason.
If you have the outlet welded to the keg you can either weld a valve directly to the keg or have a fitting welded to the keg. I prefer having a fitting on the keg and then attaching my valve to the fitting. This allows for the valve to be removed for maintenance or replacement if the valve becomes damaged. If you want to use a ball valve with a threaded connection you can have a NPT coupling welded so that it will mate to a ball valve (which are readily available). I have a personal thing against threaded connections and prefer sanitary fittings. I would have a ferrule welded in the keg and attach my valve with a clamp and gasket. This method requires a more expensive outlet valve that is more difficult to find than the ubiquitous ball valve available at every home hardware store.
I hope this information helps in your decision making process!
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