Finally!

Do you have o/a? I saw this in a gunsmithing book, use your smallest cutting tip, heat the tap to near white hot, then kill the fire and hit it with oxygen. It'll blow out in a shower of sparks. I've always been leery of trying that on an expensive gun barrel, but what the hell, it's merchant steel and you're going to scrap it anyway. Good luck.

Pete Keillor

I have had success using dental drills and a micro air driven grinder from HF. The micro grinder is similar to what the dentist use. One can grind out the center and pick out the rest. I would not advise it on taps above 1/4 inch as it isn't fast. But faster than making another part.

I have also kludged up a EDM for a guy that broke off a tap in a gun slide. Again not speedy, but it worked.

Dan

Greetings Ken, Would it matter if the hole was tapped out larger and a 6-32 tapped plug screwed in? If so then try this: Turn a piece of drill rod to .228" dia and drill a .140 hole as deep as the broken tap is long. File two or four teeth and harden it. Running slow with lots of oil or coolant, and backing out often because the chips will load fast, will get the job done. Use a small pick or screwdriver to bend the pillar with broken tap in it back and forth until it breaks off. Tap 1/4-28. Make a plug threaded 1/4-28 and tapped 6-32. I have removed taps this way. It's slow, but faster than

I feel your pain. Next time use 5-40 instead of 6-32 and pitch it as soon as it starts getting dull. 5-40 will feel like you're tapping AL when you use it in steel.

======================= I have always had problems with 10 X 24. The large majority of taps I have broken have been this size. Just normal problems with 10 X 32. Must be why the UNF series was developed.

Any reason you are using UNC 6 X 32 rather than UNF 6 X 40?

Unka George (George McDuffee) ............................. I sincerely believe . . . banking establishments are more dangerous than standing armies, and that the principle of spending money to be paid by posterity, under the name of funding, is but swindling futurity on a large scale. Thomas Jefferson (1743?1826), U.S. president. Letter, 28 May 1816, to political philosopher and Senator John Taylor

Do yourself a favor and get some 5-40 screws and taps. I learned that trick from the old guys at BAEM. They advised that 6-32 is a horrible thread design that should never have existed.

I am personally trying to use 10-32 screws and taps, wherever it is possible.

Good if you can live with a #10 head size. I can't lots of times.

I've had some luck breaking up the tap with a good automatic center punch. Takes a bit of time, but if you just keep chipping away at it, it'll eventually break up.

Pete

Never tried this but is there a chance that you can tig weld a heavy tig electrode directly to the tap and than electrode and beck it out? May time I have accidentally buried the electrode in the weld pool and it can really stick. Any variations on a theme?

Not sure how long you can wait... McMaster-Carr has tap extractors built just for this type of problem. 2561a253 is the part number for the #6 size in 2 or 3 flute style. cost about $8.00. It has hardened fingers that slip into the flutes and a collet that holds the fingers and allows you to work the broken tap out.

I've never tried them but really think it is a neat idea if it works.

Stuart

I've had luck with a home brew version of this. As long as the tap is either 2 or 4 flutes, get a couple sewing needles that are just small enough to fit down in between the flutes. The needles are VERY stiff, and a pair of pliers holding the two needles right up against the work doesn't give them much room to bend. Before I got tap extractors & a tapping guide (which means I've never used the extractors), this worked a couple times on 6-32 taps. It's easier if they broke because you slipped & snapped them due to sideways pressure. If they are jammed up from cutting straight, it will be harder.

Doug White

Thanks for all the replies guys. Why 6- 32? - What I have in stock. It is instrument work so anything bigger is a non-starter. Trying to get the tap out will probably render the part useless anyway so I might as well bite the bullet and start over. I figure that I can cut the time to two hours to re-make the part but today was just too damn cold to use the shop (Arctic front in from the Gulf of Alaska) and the rest of the week looks like more of the same. When (if?) I get this thing finished I will post photos. I only have a couple of weeks left before I head South (Honduras) for the winter and I have to get an order in for some new sails for my boat (Westerly 25) before I go. That combined with an energy level (cancer treatment aftermath) that gives me a usable daily working time of about three hours means a really tight schedule. So much to do; so little time. Fortunately My 'golden dragon' just delivered eight liters of (190 proof) medicine to assist me with my 'mental' issues.

Regards. Ken.

I owned a tap extraction shop in Los Angeles Ca. for 18 years and had people send me parts from clear across the country. Places like Boston. So it might be worth checking yellow pages and calling for price and turn around time. Jim

Carbon steel taps can be broken but HSS taps just don't break...Randy

REEEEELY? I never knew that.

LLoyd

If that statement was true, then one would never have to worry about extracting a broken tap.

I managed to break a 10mm HSS tap on Saturday. I had been using it as a thread chaser to thread a 16mmX1.5mm hole for an electrical conduit fitting. The tap was mounted in a piece of 3/4" square bar used like a boring bar holder. I reached over to get an oil rag and knocked the assembly off the bench next to the lathe. Maybe I need to install a carpet or some rubber matting on the floor or just be less clumsy....

Mark Rand RTFM