It's not like sweating copper.
Making Bulkhead fittings on the cheap
I used a 56% cad free silver
1/2" NPT: nipple, coupler, straight thread lock nut. Gotta get an o-Ring for each.
Ya gotta pre-tin the threads (make & female) with silver first. If you assemble them and hope the high percentage silver to flow in you will have about as much success as other things all full of hope tend to have.
Pre-tinning the threads is absolutely mandatory 'cause high silver doesn't flow like lead.
Unless you have some way to achieve tight control over the heat ya gotta use unfluxed silver brazing material and A high Temp flux. I used Harris Safty-Silv Black high Temp flux. It's for those apps like mine, where heat control is dicey. I used a MAPP torch, not a brazing furnace.
Then with the pipe fittings so hot (not glowing red) that the silver braze is liquidus ya gotta screw the parts together gingerly.
Bulkhead fittings 001.jpg
Bulkhead fittings 002.jpg
Clean up with file, abrasives, SST wire brush, passivate in Ascorbic Acid