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These instructions are applicable to any style of weldless bulkhead or ball valve including 2 and 3 piece versions. Common model numbers here are WLbulk, WL2PBV and WL3PBV. The instructions also apply to installing in most cylindrical beverage coolers except for the steps that involve drilling of course.
Determine Drilling Location:
In an undrilled metal vessel, the first step is to determine the center point for the hole. Whether you are converting a Sanke keg or drilling a regular pot, you must provide interior clearance for the locknut so that it does not bottom out on the bottom of the pot or get hung up on the curved part of a keg. The center point should be approximately 1" up off the bottom of the pot or above the skirt weld in the keg. It is also a good idea to position the hole away from vent holes in the keg skirt to avoid excess overheating.
Drilling the Hole:
Drilling stainless steel is a tricky maneuver if you haven't done it before but you'll get through it if you take your time and heed all warnings and tips here.
Lay the pot/keg on its side on a piece of cardboard or old carpet on the floor. Line the wall of the pot/keg with a rag or a towel to catch lubricant and shavings for easier cleanup.
The first step is to make a tiny divot or depression at the centerpoint where you intend to drill. A pointed center punch and hammer is preferred but if you don't have one, you can use a 10 penny nail. This keeps the bit from wandering across the surface. We recommend first drilling a "pilot" hole of approximate 1/8". Step bits are not great at making that first piercing cut.
Fill a shot glass or similar sized cup with vegetable oil, chuck the step bit into your drill, dip the bit about half way into the oil, position over the 1/8" predrilled hole and apply a firm pressure when you start the drill. After you reach each new step on the bit, stop. Dip the bit back into the oil and let it drip off before drilling the next step. Don't make the mistake of overdrilling the diameter. The WL bulkhead and any other 1/2" NPT penetrations require a 7/8" hole.
While you're drilling, it's best to have someone help by holding the vessel stable. Hold the drill firmly and even prop the back of the drill against your thigh if you can so that if the bit grabs and tries to rotate the drill motor in your hands, you don't hurt your wrists.
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Technique Tips and Tools:
The general mantra for drilling stainless is heavy pressure and slow speed. As the step bit turns against the work, it should be slicing a thin ribbon of material away the entire time. If the bit is spinning but NOT cutting, you run the risk of work hardening the stainless which is wear the bit down almost immediately. One of the biggest problems people have with this job is that their dril does not have enough low speed torque to allow for the pressure required to be applied. In other words, if you push as hard as you should be, some drills bog down. The user will try to overcome this problem by running the drill faster. Stop, stop.... No one likes to admit defeat but you may want to ask a friend or neighbor to borrow their drill. A 12 volt or higher cordless drill/driver that is multiple speed adjustments is highly recommended. The reason these work so well is that their speed adjustability is done with gearing, not a variable trigger squeeze. The low RPM setting provides a LOT of torque while keeping the speed slow. We love the DeWalt XRP series, not that you were shopping for a new drill.
We are being extremely wordy here, but it's important because we've received a lot of complaints about how cheap and dull our step bits are. While they are not the same quality as Klein or Greenlee, those higher end bits would also fail miserably with poor tequnique and a drill with inadequate torque. If you do not have a high torgue/low speed drill and can't borrow one from somewhere, you'd be much better off finding a plumber or electrician that can use a 1/2" conduit punch on your pot/keg. We have drilled many many holes using these "cheap" step bits and we know for a fact that you can get at least a half dozen holes drilled before you make them paper weights.
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Assuming the drilling operation went well, the next step is to deburr the hole. The back edge or interior side of a step-drilled hole is usually rolled over with a very thin layer of metal and it is SHARP. Don't go rubbing your finger over it to verify what we're saying here. No, really. Don't. A round file or a grinding stone on a dremel works well but as a last resort, wrap some sandpaper around something round like a drumstick or sharpie marker and go to work. One other way to deal with this is to drill out to 13/16" from the outside and finish up to 7/8" from the inside of the pot if there is enough room to do so. Please do not skip this deburring step as you will end up with leaks if you leave a jagged edge.
Bulkheads generally ship with two silicone gaskets (one is a spare) and one stainless steel metal washer. Remove one gasket and the metal washer leaving a single red silicone flat gasket sitting flush against the hex locknut.
Wrap the threads of the bulkhead with 3-4 turns of yellow, pink or blue teflon tape, or 5-6 turns using the thinner white teflon tape. You should be wrapping in a clockwise direction if you have the threaded end facing you.
Insert the bulkhead from inside the vessel through the hole. Start by threading the ball valve on to the threads, rotating the vavle while holding the bulkhead still on the inside. Once hand tight, hole the bulkhead inside with either a large adjustable wrench (preferred) or channel lock pliers (last resort) on the hex nut. Use a wrench or large pliers on the ball valve to snug it up. If the threads mesh before the silicone gasket inside is crushed flatter, remove the ball valve, retape the threads, and reassemble with the metal SS washer on the outside, just behind the ball valve. This washer acts as a shim.
If when tighted the ball valve is not in the desired rotational location, such as having the handle on top, it is better to loosen the assembly, THEN rotate the bulkhead the appropriate amount, rather than try to spin the assembly when tightened. The gasket inside may become torn or otherwise damaged. For example, if the ball valve handle is at the bottom, mark the bulkhead, disassemble, then reassembly with the mark on the bulkhead rotated 180 degrees. The valve should now snug up in the desired orientation.
We do NOT recommend starting with the SS washer in place on your first install attempt because if the threads do not have the chance to mesh they will leak. Do not attempt to use both silicone gaskets, the system is designed to be leak free with only one of them. |
