Help! Busted off tap in SS part

[Bob W.]

I have a lot of time into this part and I busted of a #8 thread forming tap because I mistakenly posted the op as a drill cycle instead of a tap cycle. The tap is stuck in a through hole (.2" deep) that is easily accessible. What would be the best way to remove this?

 

I know an EDM could do it, but how about a carbide spade drill or a small end mill? I know the tool would be destroyed in the process buy it would still be cheaper than sending it out.

 

Thanks,

Bob

[Teh Bear without Brains kinda idiot]

but how about a carbide spade drill or a small end mill?

~~~~~~~~~~~

I prefer end mill .

What is your end mill for your tap .

I am metric ,so #8 tells me nothing

Give ne your em diameter and I will give recommendations

[DavidB]

Is the Tap Carbide or HSS?

[Storkman]

if it is a HSS tap just plunge a carbide endmill down through it.

[Guest]

I'd be be careful with the term used there "plunge"

 

It's more like nibble away at it, lest you end up with broken carbide in there.

[chris m]

Hey Winnie, #8 is American for M4

 

Forming taps are tougher to remove than cut taps; I'd chip away at it with a 2fl carbide endmill

 

You might want to try to run a dead tool [worn out drill or something] in reverse and push on it a little because sometimes you back 'em right out if you're lucky. Gotta do that in the Bridgeport, though...

[Guest]

EZ Outs

[Namliek_J@TheeCircle™]

I cut out alot of 10-32 Elektralube taps with a .125 Carbide Endmill. Crank the spindle up to about 5000 to 7500 RPM. Jog down until you touch the tap and start feeding very slowly. I usually feed about .5 inches a minute. Use an airline to keep it cool. Should have no problem. Dont go too fast or you will melt the endmill and have to EDM the hole out.

 

Thread forming taps are more tricky because they dont have flutes. The 10-32 taps that I use are 2 flute gun taps so they have the flutes which make fore easy removal. Best of luck.

[Thad]

We drill them out with a carbide ball nose; about .5 IPM and .005 - .010 peck. Go get a cup of coffee and it's done when you get back.

 

Thad

[Hardmill]

quote:

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We drill them out with a carbide ball nose; about .5 IPM and .005 - .010 peck. Go get a cup of coffee and it's done when you get back.

---

:GOLF CLAP:

 

PEACE

[Bob W.]

I set the mill at .0001" jog and manually pecked at it with a .125" carbide end mill in .003" increments, and it came out great. I saved the part and I didn't lose the end mill either. Thanks for the help.

 

Bob

[Teh Bear without Brains kinda idiot]

I usually drill them out with end mills too .

Slow rpm and slow feed

Cooling -air

For end mill 3 mm i would give 400-500 rpm and jog it slowly

No need for high rpm on manual feed and this is also safety .

If you are wearing glasses that`s not protects your other parts .

Those of you folx ,who are professional conventional milling machine machinists know that on 600 rpm you can mill everything

[scoomes]

when I was a pup, and working with this old guy who set up the original hp model shop, he broke a 6-32 tap off in a tool we were working on and cursed a little. A snotty young engineer standing near buy comented that he had never broken a tap. Quick as a wit the old guy comes back with "you havent tapped many holes have you?

[Guest]

heres a trick i learned for getting a blind sheared off dowel pin out.drill a small hole thru the center.fill the hole with candle wax.take a drill blank a few thousands under and drive the pin down thru the hole. the wax will force the pin out or a least it did for me.

[DavidB]

del,

I've seen this method too but with Greese.

 

I've also seen a toolmaker with a blind hole with a broken drill in it, fill it up compact with match heads then light it. BANG out fly's the drill.

[FeareFerretNC]

DavidB.. I have seen that "bang" as well... the little b***** dowel hurt when it hit me in the back of the head.

 

1. If i have a broken tap (non carbide, cuz i have never used a carbide tap), EZ Out is great in most cases, but an old worn carbide end mill is the best...

 

2. after my little crack in the head (yeah it happened, but maybe he just hit it through the clearance hole ) for dowels i drill a hole, force some putty down there and use a drill or drive punch to get it out.

 

theres my 3 cents (inflation)

 

FF

[#Rekd™]

Hi,

 

If the tap or tool is HSS we have an acid mixture that disolves the tool and does not touch the stainless steel, if it is in aluminum we put it it the anodizing tank and it will remove it there!

 

John Ford

[Brad MacKinnon]

when this happens to me i perfer to do it manually and not in the cnc. and use a carbide endmill or left hand carbide drill. I find it alot better manually cause you have all the feel unlike the cnc.

 

We generally get about 4-6 parts a week that we have to remove broken blots, screws, work hardened snapped pins etc. being a job/repair/cutsom shop.

 

another thing i seen that wasnt mentioned was that if you have enough matl. sticking out of the part you can weld a nut or an extension and a nut and remove it that way. If its a quick and drity kind of job.