GEARWRENCH 5/16 x 18 NC Taper Tap Review
I purchased this tap from Amazon on September 13th of 2019 to repair damaged thread holes on the primary mounting flanges of a aftermarket Harley S&S 107ci Super Sidewinder Evolution motor.
First let me preface this by saying "I typically have had good experiences with Gearwrench products".
A common question asked on the Amazon Q&A section was "Hot long is the tap?". As seen in the picture above:
Length: 2 3/4 inches
The packaging is a standard click to lock plastic container.
For all tapping and drilling I use the same ancient bottle of 3-1 Household oil (with lubrashield!). I'm pretty sure I bought this at a yard sale 20 years ago.
Here is a picture of the tap loaded up with oil (overloaded). It sounds silly but not all taps hold oil the same way. I would imagine it has to do with the finishing of the material used to make the tap.
The tap cut cleanly and retained the metal shavings in the fluted recesses. I could not hand tighten the socket head bolt in to this thread before hand, but was just about able to thread the tap in with only minimal resistance.
The threads cut true and after a quick spray of carburetor cleaner, the fastener threaded in perfectly with no wobble.
Buy it if you need to cut or chase threads in aluminum. I have not tried it with steel, but I think going slow with enough lubricant should be no issue.