Tapping Weld in Bungs for Links

Toddy · Jul 10, 2015

Taps are about like anything else, you get what you pay for. We ordered a bunch from Grainger one time and some of the smaller taps weren't even the right thread. Said one thing on tap but was cut to another size.

Best bet for what your doing is prob a EBay tap. New taps in that size are usually big bucks. For the most part big taps like that won't be used much and tossed out and end up on eBay. If you just plan on chasing threads look for a bottom tap if you plan on threading links or making bungs a starter or plug will be needed.

Elliott · Jul 10, 2015

Tapping fluid and holding it straight and you shouldn't have to do anything else

ranger11 · Jul 10, 2015

Re:

Tap magic for cutting new threads. I agree with the others on getting the wrong tap. Measure out 1" on the tap and see how many threads are in that 1" section.

kmcminn · Jul 10, 2015

Whenever I buy taps or drills, I always buy Made in the USA. You can expect to pay at least double but the quality is there. Good taps last for years, cheap Chinese taps may last 2 or 3 times. Also try to make sure you use the correct size tap drill. A 1/32 either way on the size will make them tight or loose. Also if your drill has been sharpened the person could have ground one side more than the other,that will also make it drill bigger. You could check that by drilling a test hole in a separate piece of material then check the inner diameter with some calipers. That is where I would check first but I am no machinist either.

patooyee · Jul 10, 2015

When The Boss and I were doing some links in my lathe we found that if we just powered right through the entire tap the threads would turn out looser than if we went a little ways, backed out, blew all the chips out, went a little further, backed back out again, etc.

I agree with everyone here, seems like something is messed up about your tap. But I figured I would add the little bit of experience I have with this.

GT_Buggy · Jul 11, 2015

Thanks for all the feedback guys.

kmcminn said:
Whenever I buy taps or drills, I always buy Made in the USA. You can expect to pay at least double but the quality is there. Good taps last for years, cheap Chinese taps may last 2 or 3 times. Also try to make sure you use the correct size tap drill. A 1/32 either way on the size will make them tight or loose. Also if your drill has been sharpened the person could have ground one side more than the other,that will also make it drill bigger. You could check that by drilling a test hole in a separate piece of material then check the inner diameter with some calipers. That is where I would check first but I am no machinist either.

I am just trying to chase the threads in the bung. After it was welded the rod end would not go in. I tried putting it in a vice and a huge screw driver and it still wouldn't got in. Figured a tap would do the trick but I guess I need to find a better tap.

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outlaw yota · Jul 12, 2015

i coat threads on rod end with antisieze,then put it together.clean any excesses off,weld then pull rod end out.i've never had to rechase threads with that method,done probably 20! :smoke:

mac5005 · Jul 12, 2015

outlaw yota said:
i coat threads on rod end with antisieze,then put it together.clean any excesses off,weld then pull rod end out.i've never had to rechase threads with that method,done probably 20! :smoke:

Done this on a dozen links or so, never had a problem.

I tigged one set with just the tube adapter in the dom, and had to force the heim in with cutting fluid when done. Thought I had ruined $$$ in dom and inserts.

Now I stick to quoted method. Works for tigging the root and plug welds or migging the whole thing.

Just very diligent about getting the heim out and cooled off ASAP.