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I'm sold on tap and die sets now and my bumper is secure!

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kinggeorge13:
My 1978 Bus has not had a rear bumper in the past three years so I decided this past weekend was the weekend I was going to tackle installing a donor bumper I bought in Vancouver over two years ago (my projects take forever.....).    Well what a surprise, the original 4 holes in the frame that the mounting bolts attached into were in useless condition from rust/corrosion and one of them had the original bolt snapped off in the hole.   So I slowly got the old bolt drilled and punched out.   

Then I drilled out all four holes significantly larger with a 27/64 drill that was specified for preparing for a 1/2" coarse thread bolt.   Went and bought my first tap and die set at Cdn Tire cuz it was one of those 70% off sales (who buys anything at full retail at Cdn Tire????).   I planned to use 1.5" long, 1/2" wide coarse thread bolts which were significantly larger (wider) than the originals.    The drilling made nice clean holes of pure metal (no rust).   

I then went to use my new tap to cut threads into my four new mounting holes only to find no way in a million years there was any space at all for the T-handle to turn up in that space.   Canadian Tire did not have anything I could find to solve this but Princess Auto did:  the answer was a "chuck" made specifically for this purpose and for holding the square ends of the taps.    The other end of the chuck was a typical 3/8" female connection for using your socket set ratchet and extension bar with.   It all went perfectly.   As you can imagine, the frame back there for mounting the bumper to is darned thick and it took some effort to turn the tap and cut those threads but once it started it instantly "bit" into the metal and guided it's way into the hole.   The trick (and the only way it works correctly without destroying your tap) is to use oil lots and to keep stopping and turning the bit in reverse lots of times as you progress into the hole to allow the tool to clear out the bits of cut metal from the new threads. 

I'm sure lots of you have done this so many time you are reading this and thinking "um yeah, we all do that all the time" but I'm still sure there are lots of others like me out there still learning as we go and for me this was the first time I'd actually done it and man-o-man, my threads turned out really nice and deep and allowed me to crank on my new bolts nice and tight to get that bumper mounted.   Before I started I considered just welding on the bumper but that seemed such a hack and it was an opportunity to buy a couple new tools and I'm very happy with the results.   

silas:

--- Quote from: kinggeorge13 on June 29, 2017, 08:37:56 AM ---...my first tap and die set...a couple new tools and I'm very happy with the results.   

--- End quote ---

yup!! a tap & die set is a great tool and something that everyone doing their own repairs should have! :)

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