Spiral Point Taps.

[Ace]

I posted this in another thread to SR5Dave, but I thought it would be of interest to all.

If your tapping with standard taps and having a hard time of it, pick up a set of spiral point taps. I promise you won't be disapointed!

I have this set, and highly recommend it, also includes the proper drill size for each tap:

http://www.use-enco.com/CGI/INSRIT?PMAKA=309-1003&PMPXNO=949033&PARTPG=INLMK32

Smallest is 6-32 though, so be sure to order a 4-40 spiral point if needed.

This lube is awsome too, for tapping and drilling:

http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=825-8140&PMPXNO=940175

[MUD4FUN]

Spiral points are normally used on machines/tapping heads. The problem with them is they have a much longer taper lead on the nose of the tap which limits the depth of thread cutting for a blind hole unless you drill much deeper - not normally a problem though.

You can also modify them by grinding the nose of the tap off a few mm or 1/8inch short of where the full thread starts but still leaving enough lead on it to allow you to get a start when hand tapping but allowing a better depth of thread or a shallower hole.

I usually grind a slight taper on my normal hand taps anyway to help getting a start in the hole. Only takes a few seconds on a bench grinder. :)

PS. If anybody ever runs out of tapping lube and needs a thread cutting urgently try using WD40, it makes things alot easier than dry cutting and lessens the chance of breaking the tap. I use it alot when cutting aluminium which tends to 'stick' to the tap otherwise.