...maybe easy is the wrong word. Usually I subscribe to "if it's not broke, don't fix it", but when I found my old plated bulkhead completely rusted 2 hours before brewday, I knew it was time for a switch.
I recently rebuilt all of my bulkheads from stainless fittings in the Blichmann style. I thought I would share the design (as read at http://www.theelectricbrewery.com/).
A quick disclaimer, measure twice; order once, when buying from Mcmaster. This project was a lot of trail, error, and spare parts, but the below items worked for me. Hopefully my record keeping is correct, and the design will work for you too.
From what I read, Blichmann uses a bulkhead design that rests a thick high temp o-ring INSIDE a slightly thinner stainless shim on the outside of his weldless fittings, and uses a locknut on the INSIDE of his products to "pull" the fitting/ball valve against the vessel, compressing the o-ring enough to seal, but leaving you unable to over-tighten and ruin the o-ring. In other words, you can only compress the o-ring to the thickness of the Shim; enough to seal, not enough to crush/contort.
There is a great picture of what I awkwardly explained at the above website, but the gentlemen gave part #'s for a 1" conversion, leaving me to figure out 1/2" and 3/4" conversions myself.
The design is as follows (from outside the kettle->in)
(for 1/2")
SS Barb/QD/Etc with 1/2 male threads
1/2 SS Ball Valve/or whatever fitting you are trying to set.
1/2xClose Nipple
Small SS Shim (to compress against o-ring, because the diameter of the BV is too small to grab it) - Mcmaster 98126A706 - .048 Thick, 1"ID, 1-1/2"OD
Large SS Shim - Mcmaster 98126A803 - .09 Thick, 1-1/8"ID, 1-5/8" OD
High Temp Silicone O-ring (actually sits inside Larger Shim) - Mcmaster 9396K32 - 13/16" ID, 1/8 width, 1-1/16 OD
Kettle/MLT/HLT Wall
Small SS Shim (to protect inside wall from the torque of the lock nut) - Mcmaster 98126A706 (Same as Small Shim Above)
1/2 SS locknut - I bought from Bargain Fittings . com, very happy with speed of service, and it seems one of the few places to get SS Locknuts at a decent price.
(for 3/4")
1/2 MPT SS Barb/QD/Etc
3/4x1/2 SS Bushing
3/4 SS Ball Valve
3/4xclose SS Nipple
Small SS Shim - Mcmaster - 98126A803 - .09" thick, 1-1/8" ID, 1-5/8" OD (Again, the valve's diameter is too small to pinch down on the o-ring, so I needed a second shim to do the compressing against the o-ring. In the design at the electric brewery website, the gentelman was using a large electric box to do the "o-ring compressing" so diameter was not a factor)
Large SS Shim - Mcmaster - 98126A809 - .09" thick, 1-3/8" ID, 1-7/8" OD
High Temp Silicone O-Ring (once again, this actually sits inside large shim) Mcmaster - 9396K32 - 1" ID, 1/8" Width, 1-1/4" OD
Kettle/MLT/HLT Wall
Inside Shim - Mcmaster - 98126A430 - 1-1/8"ID , 1-5/8" OD, .008" thick (I bought this super thin so that it could flex and would not take up too much prescious space on the nipple. The more thread on the inside, the easier it is to attach a coupling/reducing coupling for manifolds, dip tubes, etc.)
3/4 SS Locknut - once again, from BargainFittings.com
The main factors to keep in mind are that the OD of the o-ring has to be less than the ID of the Large shim, and the ID of smaller shim has to be less than the OD of the o-ring. That sentence gave me a headache.
I like this design for a few reasons.
1.) fool proof. The 1/8" (.125) thick o-ring is carefully selected to be thicker than the .09" thick shim. The difference is enough to create a seal, but not enough to over-tighten and ruin the seal.
2.) Stainless - It looks nice, it lasts forever, and you have no issues with dis-similar metals.
Good Luck,
Joe
I recently rebuilt all of my bulkheads from stainless fittings in the Blichmann style. I thought I would share the design (as read at http://www.theelectricbrewery.com/).
A quick disclaimer, measure twice; order once, when buying from Mcmaster. This project was a lot of trail, error, and spare parts, but the below items worked for me. Hopefully my record keeping is correct, and the design will work for you too.
From what I read, Blichmann uses a bulkhead design that rests a thick high temp o-ring INSIDE a slightly thinner stainless shim on the outside of his weldless fittings, and uses a locknut on the INSIDE of his products to "pull" the fitting/ball valve against the vessel, compressing the o-ring enough to seal, but leaving you unable to over-tighten and ruin the o-ring. In other words, you can only compress the o-ring to the thickness of the Shim; enough to seal, not enough to crush/contort.
There is a great picture of what I awkwardly explained at the above website, but the gentlemen gave part #'s for a 1" conversion, leaving me to figure out 1/2" and 3/4" conversions myself.
The design is as follows (from outside the kettle->in)
(for 1/2")
SS Barb/QD/Etc with 1/2 male threads
1/2 SS Ball Valve/or whatever fitting you are trying to set.
1/2xClose Nipple
Small SS Shim (to compress against o-ring, because the diameter of the BV is too small to grab it) - Mcmaster 98126A706 - .048 Thick, 1"ID, 1-1/2"OD
Large SS Shim - Mcmaster 98126A803 - .09 Thick, 1-1/8"ID, 1-5/8" OD
High Temp Silicone O-ring (actually sits inside Larger Shim) - Mcmaster 9396K32 - 13/16" ID, 1/8 width, 1-1/16 OD
Kettle/MLT/HLT Wall
Small SS Shim (to protect inside wall from the torque of the lock nut) - Mcmaster 98126A706 (Same as Small Shim Above)
1/2 SS locknut - I bought from Bargain Fittings . com, very happy with speed of service, and it seems one of the few places to get SS Locknuts at a decent price.
(for 3/4")
1/2 MPT SS Barb/QD/Etc
3/4x1/2 SS Bushing
3/4 SS Ball Valve
3/4xclose SS Nipple
Small SS Shim - Mcmaster - 98126A803 - .09" thick, 1-1/8" ID, 1-5/8" OD (Again, the valve's diameter is too small to pinch down on the o-ring, so I needed a second shim to do the compressing against the o-ring. In the design at the electric brewery website, the gentelman was using a large electric box to do the "o-ring compressing" so diameter was not a factor)
Large SS Shim - Mcmaster - 98126A809 - .09" thick, 1-3/8" ID, 1-7/8" OD
High Temp Silicone O-Ring (once again, this actually sits inside large shim) Mcmaster - 9396K32 - 1" ID, 1/8" Width, 1-1/4" OD
Kettle/MLT/HLT Wall
Inside Shim - Mcmaster - 98126A430 - 1-1/8"ID , 1-5/8" OD, .008" thick (I bought this super thin so that it could flex and would not take up too much prescious space on the nipple. The more thread on the inside, the easier it is to attach a coupling/reducing coupling for manifolds, dip tubes, etc.)
3/4 SS Locknut - once again, from BargainFittings.com
The main factors to keep in mind are that the OD of the o-ring has to be less than the ID of the Large shim, and the ID of smaller shim has to be less than the OD of the o-ring. That sentence gave me a headache.
I like this design for a few reasons.
1.) fool proof. The 1/8" (.125) thick o-ring is carefully selected to be thicker than the .09" thick shim. The difference is enough to create a seal, but not enough to over-tighten and ruin the seal.
2.) Stainless - It looks nice, it lasts forever, and you have no issues with dis-similar metals.
Good Luck,
Joe
