The 1/2" sized pull through solder fittings have been around for a while and I couldn't be happier with the ease of install for even the most novice DIY soldering garage warrior. Then I made the radius faced TC fittings that could also be soldered on the outside of kettles. No problem there either, but the fittings are bulky and expensive to make so I'm working on getting cheap ferrules installed in a classy way. This isn't a new idea by any means so I'm not taking credit for that.
Here's where I am so far.
The key is in the tapered bullet mandrel and die along with a hardened drawing bolt. The trailing edge of the bullet is notched just enough to stay centered in the opening of the TC ferrule.
You'll make a hole in the vessel at 1.25" and this is what the mandrel looks like poking out of the hole:
Then you put the die in place on the bolt and tighten everything up. Lubrication on the kettle and mandrel helps. After the bullets pops through, you're left with a flared opening.
What I really didn't know at this point was if it were possible to pull the TC ferrule into that hole from the outside in because the flared opening does spring back to the point where the ID is nearly 1-3/8" instead of 1-1/2". I mean, it's obvious that you can pull it in from the larger side of the flare and that would be fine if you don't mind the soldered area being visible on the outside of the pot, but it will look better this way.
I reloaded the bullet mandrel onto pulling bolt but this time I put a TC ferrule behind it and used a drilled TC cap as a backing behind the bolt head. The cup die is then moved to the inside of the pot.
The bullet stretched the opening back up again just enough for the ferrule to pop in. I'd imagine easing the outside leading edge of the ferrule with sandpaper would make it a little easier. You also don't want the inside of that drilled hole to be sharp and burred at all or this may not work.
It looks pretty sweet to me.
Look at that fit and finish. A touch of solder in that valley and Bob's yer uncle.
I need to do some more testing on thicker-walled vessels to see if it's just as easy. The coolest thing is that I can't even budge the fitting by hand and it almost holds water without soldering (slow drip). The fit can't get any better than that. I have to work on sourcing the die part at a reasonable cost and then I'll have the tool ready to go. It uses the same bolt, nut and washers as the existing pull through tool.
Here's where I am so far.
The key is in the tapered bullet mandrel and die along with a hardened drawing bolt. The trailing edge of the bullet is notched just enough to stay centered in the opening of the TC ferrule.
You'll make a hole in the vessel at 1.25" and this is what the mandrel looks like poking out of the hole:
Then you put the die in place on the bolt and tighten everything up. Lubrication on the kettle and mandrel helps. After the bullets pops through, you're left with a flared opening.
What I really didn't know at this point was if it were possible to pull the TC ferrule into that hole from the outside in because the flared opening does spring back to the point where the ID is nearly 1-3/8" instead of 1-1/2". I mean, it's obvious that you can pull it in from the larger side of the flare and that would be fine if you don't mind the soldered area being visible on the outside of the pot, but it will look better this way.
I reloaded the bullet mandrel onto pulling bolt but this time I put a TC ferrule behind it and used a drilled TC cap as a backing behind the bolt head. The cup die is then moved to the inside of the pot.
The bullet stretched the opening back up again just enough for the ferrule to pop in. I'd imagine easing the outside leading edge of the ferrule with sandpaper would make it a little easier. You also don't want the inside of that drilled hole to be sharp and burred at all or this may not work.
It looks pretty sweet to me.
Look at that fit and finish. A touch of solder in that valley and Bob's yer uncle.
I need to do some more testing on thicker-walled vessels to see if it's just as easy. The coolest thing is that I can't even budge the fitting by hand and it almost holds water without soldering (slow drip). The fit can't get any better than that. I have to work on sourcing the die part at a reasonable cost and then I'll have the tool ready to go. It uses the same bolt, nut and washers as the existing pull through tool.
