I was cleaning the threads for the head bolts in the block when a oh-no happened.Any ideas for getting the rest of the tap out? broke off 1/4 inch below the deck surface.thanks Bob Adamsky

Sounds more like an OH $HIT :eek:

I did that once on a timing cover bolt hole. I just left it in there. I don't know how you would get it out........Sorry

Look in the phone book on Monday & start calling machine shops in your area to find one that has an EDM, sometimes called a tap burner. Tell them it is a block. It will usually take the tap out without hurting the threads.
Try general machine or cnc machine shops.

You also can use a carbide bit if you can find one.We have had a few at work break and had to use a carbide rotory file in a grinder but only when the hole dia. alowed access.We then could work the end to where we could shatter them, but this would be a last resort.

GoodLuck :eek:

Can you get two small straight shanked punches down the sides between the four flutes and hopefully twist it out??

pdq67

Snap-on sells a left hand drill bit, that will usually spin it out as soon as it grabs the first time. I bought it as a set of drill bits and easy-outs. hope it helps!

A machine shop supply house should have tap removers (this sort of thing happens more than any machinist will let on smile.gif ). They are not expensive. EDM will likely cost you about $40.

Sometime you can take a needle nose pliers or screwdriver to turn them out. If you broke it because it bottomed out you may take a punch and back it out with a tap. Otherwise the machine shop sounded like the right choice. Mark

if you twisted that big tap hard enough to break it look at getting it burned out.WORST case you will try and shatter it with a hardened punch.

Thanks everyone,think i will call the machine shop on Monday.Spent the last 2 evenings trying turning,twisting,needle nose and drilling.tap is lose moves less than a 1/8 turn.Think it will need some thread repair.Good thing is it time for Chevelles at Daytona(turkey rod run)


Thanks Bob Adamsky

Originally posted by bob_adamsky:
Thanks everyone,think i will call the machine shop on Monday.Spent the last 2 evenings trying turning,twisting,needle nose and drilling.tap is lose moves less than a 1/8 turn.Think it will need some thread repair.Good thing is it time for Chevelles at Daytona(turkey rod run)


Thanks Bob Adamsky Bob,
The reason it only turns about 1/8 turn is when a tap breaks it usually shatters & is in more than one piece.
If the tap seem to move than a tap extractor will most likley remove it as Pat said.
A drill will not touch a tap. You will just end up screwing up the hole.
Tap extractors come in 3 & 4 flute types depending on what type tap you had. The 2 & 4 flute taps use the 4 flute type you just remove two "legs"
The way they work is they have small "legs" that drop down between the tap flutes & keep all the broken pieces turning at once so it will hopefully back out.
I have both sets & about half the time they work :(
Carbide drills, hammers, chisels etc have their place but in my opinion removing taps from a hole you would prefer not to screw up is not one of them.

Those broken tap removers work great.As was stated above,theres either 3 or 4 "legs" that extend down into the flutes of the tap so it all comes out at once.I recentley snapped off a head bolt on a SB & was able to work the piece out with a center punch.I'll never re-use head bolts agian. graemlins/clonk.gif
I got lucky me thinks.

Matco man is in tomorrow,80.00 for a set of extractors .I got to try it,then i will spend 80.00{est.} at the machine shop.

I worked on my neighbors vette a few weeks ago who had a broken easy-out in his head for one of his valve cover bolts. I spent three hours using several carbide bits on a dremmel tool to slowly grind away the easy-out. I then drilled it and installed a helicoil. Worked great but you have to be real careful you don't enlarge the hole. I think I used a 13/64ths bit for a 1/4-20 heli-coil/bolt. What a PITA. I would definitely try the tap extractor first though. Good Luck.

THEY WORKED!!got the broken tap out using the tap extractors graemlins/hurray.gif graemlins/hurray.gif saved the thresds too graemlins/hurray.gif That was the first time i had used the extractors.They were the 4 prong from Matco.
Thanks everyone
Bob Adamsky

cool deal, Bob. I've seen these but never bought any because I didn't think they would work. Open season on a set of them now.

Tom

Those things only work if the threads are already there. If you break a tap while cutting threads, these isn't a chance those things will work. I've destroyed more than one in my day!

Jeff