Finally got the tap for my screwed up keggle welds.

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Skrimpy

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For those of you that missed my thread, two links for reference...
https://www.homebrewtalk.com/f51/help-welder-didnt-do-what-i-wanted-103809/
https://www.homebrewtalk.com/f51/possible-solution-my-welding-problem-107638/

So I ground down the inside lip of the opening in one of my keggles with a dremmel and grinding stone bit. Then I went out and bought myself a pipe tap and got up the guts to give it a go on the gummed up threads. After some jiggling up/down, back/forth and clockwise/counter-clockwise, it worked like a charm. Opened the threads right up and the tap goes in and out all the way to the center of the coupler. Now I have another problem. I tried to fit a 1/2 inch copper nipple in and......

bzzzzz.....wrong answer Skrimp. Thanks for playing. We have some wonderful parting gifts for you.

It won't go. Can't even get the thing to go in a half turn before it gets too hard even to turn with a wrench. I know the copper nipple is still good b/c it still fits into the one weld the welder did right. Anyone got any ideas? Poor cleanup? Cross-threaded? Do I need to find another way to do this?
 

fifelee

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It is a tapered thread and the tap likely doesn't go in far enough to completely clean up the threads. The threads in a coupling end abruptly at in the middle and that will stop you tap from going is as far as it needs to. You could grind some off the end of you tap so it will go in farther, but that is a bitch. I took a dremel and a small cutting wheel and touched up the high spots on the threads, but that is also a bitch inside a keg. No real good answers. Maybe a really big countersink bit and just take out the first few thread which are likely the ones that are messed.
 

Dwain

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Skrimpy,
I believe they make a bottom tap for NPT. It is called a bottom chamfering tap and is used to thread a blind hole when complete threads are needed "almost all the way to the bottom". I googled bottom chamfering tap and found this company. Give them a call and see what they can tell you. Untitled Page Let us know what they say. Luck - Dwain
 

fifelee

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Found some more info. Normal taps have a long lead in that doesn't do much cutting but guides the tap into the hole. (that sounded dirty) This is bad for blind holes as you can't get threads to the bottom of the hole. In cases when you need threads to the bottom they make special taps called "bottom" taps. These tap have cutting flutes all the way to the end. The problem is that they are harder to start in a new hole, but should be fine for you. I didn't think they made bottom taps for NPT thread, but google is amazing.

NPT Bottoming Pipe Taps HIGH SPEED STEEL - GROUND THREAD

I think this is a NPT bottom tap. The picture is of a normal tap, but the description sound like what you need. I think it must just be a stock pic. Anyway do some searching for "bottom tap"
 

bull8042

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You can use a regular pipe tap, but you have to do it from the inside. If you run a regular tapered NPT tap in far enough from the outside to clean out the holes, the threads will be way over-sized on the outside.
 
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Skrimpy

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You can use a regular pipe tap, but you have to do it from the inside. If you run a regular tapered NPT tap in far enough from the outside to clean out the holes, the threads will be way over-sized on the outside.
Ran it from the inside. I'm liking the bottoming (shorter?) pipe tap idea to finish the job on those first few threads. I'm going to try that before going with something more drastic. My thinking is these guys are right and I just haven't been able to get the tap in far enough to completely open up the boogered threads. I'd keep forcing it but I turn as hard as I can on the sucker and it won't move a bit more. If I don't get it to open up (I am told) that I can force the copper in with some teflon and it will form to the boogered threads and won't leak, but I would rather not force it. I'd rather it just went in the way it is supposed to. till next time...:rockin:
 

hooks

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I'd use a pipe tap with lead on it to ensure you are straight with the previously taped threads. Good luck as rechasing threads like that inside a keg will be a royal pain.
 

budrockdiesel

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Why not use a compression fitting, drill out the lip and make your dip tube long enough to go through and through the keg. Then connect your ball valve to the tube with another compression fitting. Wont be the most beautiful job but it would be easey. Just a thought.
 
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Skrimpy

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I'd use a pipe tap with lead on it to ensure you are straight with the previously taped threads. Good luck as rechasing threads like that inside a keg will be a royal pain.
Already have one done, the tap went in just fine. I think it just needs a little more cleanup after hearing some of these suggestions.

Why not use a compression fitting, drill out the lip and make your dip tube long enough to go through and through the keg. Then connect your ball valve to the tube with another compression fitting. Wont be the most beautiful job but it would be easey. Just a thought.
This is the drastic measure I was talking about. I didn't want to have to be unhooking two compression fittings and feeding a 3/8 tube through the couple every time I want to clean. Besides, doing that would make the welding pointless and the money spent, wasted.
 
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Skrimpy

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Finally found some time to get out in the garage and work on this thing...

I tired to mess with the thing before going out and buying the bottom chamfering tap. I forced the tap a little bit and jiggled the thing around in there to try and break some of the gunk up. Then I blew some compressed air in there. copper nipple went in like a charm. three 180 degree turns. Plenty far in the coupler to attach a syphon tube! I'm in business! Just have to build a chiller and will be all set! I might make big brew day! My LHBS is giving away extract kits and grains if you are brewing one of the official brews for big brew day on may 2nd! I don't think I can pass up 5 gallons of free beer! Especially good beer like homebrew! SWEET!

Bobby,
I think I owe you some serious brew. Between your advice, videos, ideas and inspiration you've given me, I probably should have just paid you 1k to build me a system...and mine isn't even done yet but there seems to be light at the end of the tunnel.
 
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