Welcome to Club Cobra! The World's largest
non biased Shelby Cobra related site!
- » Representation from nearly all
Cobra/Daytona/GT40 manufacturers
- » Help from all over the world for your
questions
- » Build logs for you and all members
- » Blogs
- » Image Gallery
- » Many thousands of members and nearly 1
million posts!
YES! I want to register an account for free right now!
p.s.: For registered members this ad will NOT show
Main Menu
|
Nevada Classics
|
Advertise at CC
|
January 2025
|
S |
M |
T |
W |
T |
F |
S |
|
|
|
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
14 |
15 |
16 |
17 |
18 |
19 |
20 |
21 |
22 |
23 |
24 |
25 |
26 |
27 |
28 |
29 |
30 |
31 |
|
|
CC Advertisers
|
|
07-01-2008, 06:52 AM
|
|
CC Member
|
|
|
Join Date: Apr 2008
Location: Mechanicsburg,
PA
Cobra Make, Engine: Everett-Morrison, 429CI
Posts: 98
|
|
Not Ranked
Why not use a tool called a tap extractor? They sell them with the number of fingers to match the number of flutes of the tap. The fingers are hardened, not too hard and brittle, but more like spring steel. You clean out any chips which curl up in the flutes slide the extractor fingers into the flutes, slide the collar down to reduce flex in the fingers and use a tap wrench to remove the tap. If that doesn't work the tap will have to be burned out on an EDM machine. Don't worry about going oversize on the hole. You can always redrill it and use a thread insert or helicoil.
|
-
Advertising
07-01-2008, 11:15 AM
|
|
Member of the north
|
|
|
Join Date: May 2003
Cobra Make, Engine: A Cobra
Posts: 11,207
|
|
Not Ranked
5 pound sledge and a drift pin. If it broke once, it will break again.
|
07-01-2008, 11:44 AM
|
|
CC Member
|
|
|
Join Date: Jan 2008
Location: Williamsport,
PA
Cobra Make, Engine: Kellison Stallion 468 FE
Posts: 2,703
|
|
Not Ranked
taps arrrgh
for the sole purpose of saving the workpiece, in this case the DOOR !
i have found a left hand cut endmill ran in the counterclockwise direction
will extract all if not some of the tap. the rest can be pulverized with a small
tipped drift. taps are hard but brittle they can be shattered.
|
07-01-2008, 11:48 AM
|
|
CC Member
|
|
|
Join Date: Dec 2006
Location: Corona del Mar,
CA
Cobra Make, Engine: FFR MKIII, FMS BOSS 302 "B" cam
Posts: 170
|
|
Not Ranked
Go to mcmaster-carr.com and search for tap extractor (it's catalog page 2507).
I broke off a tap while drilling out my spindles. The tap extractor works. Be gentle working it back out. Back and forth, back and forth. I'd wager forcing it is what broke it in the first place. Tap slowly, not continuously.
HTH,
|
07-01-2008, 12:34 PM
|
|
CC Member
|
|
|
Join Date: Jan 2008
Location: Williamsport,
PA
Cobra Make, Engine: Kellison Stallion 468 FE
Posts: 2,703
|
|
Not Ranked
link
|
07-01-2008, 12:43 PM
|
CC Member
|
|
|
Join Date: Mar 2001
Location: Madison, AL,
al
Cobra Make, Engine: Midstates in-work again
Posts: 73
|
|
Not Ranked
Back drill the hole it should turn the tap then plug the hole or move the hole location. Taps are a ***** to get out.
__________________
Treblig
|
07-01-2008, 12:52 PM
|
|
CC Member
|
|
|
Join Date: Sep 2002
Location: Fort Worth,
TX
Cobra Make, Engine: Superformance Roush 427
Posts: 436
|
|
Not Ranked
Glyn, db here, give me a call 214.725.7585
__________________
Don Barnes
Driving Instructor
texasdrivingexperience.com
Texas Motor Speedway
|
07-01-2008, 12:59 PM
|
CC Member
|
|
|
Join Date: Mar 2007
Location: Daly city,
ca
Cobra Make, Engine: classic roadster,408cu
Posts: 212
|
|
Not Ranked
Baz, in the aircraft industry this happens to the best of us !!! sometimes it is in a part costing hundreds of thousands of dollars EDM is the least destructive and going down the list to a carbide burr on a high speed grinder ..with patience it will eat it up and if not perhaps you can eat the surrounding metal enough to move it or punch it through . I do not have much faith in the tap removers especially after you tried hitting it through. Baz I have used the cabide burr with much success and it is very cost effective feel free to PM me if you need more info ...WD
|
07-01-2008, 01:55 PM
|
CC Member
|
|
|
Join Date: Mar 2006
Cobra Make, Engine:
Posts: 277
|
|
Not Ranked
Have you tried shrinking the tap by freezing the area with a CO2 fire extinguisher. Shrinks away both the tap and the base materia. Rag up the area around the hole to confine the CO2. I have used this method many times in removing corroded-in-place bearing cages ,and the like. Common practice for us Salt water mechanics.
|
07-02-2008, 03:44 AM
|
|
CC Member
|
|
|
Join Date: Feb 2006
Location: Perth,
WA
Cobra Make, Engine: RMC 302 Windsor Supra 5 speed Jag Suspension
Posts: 139
|
|
Not Ranked
Hi Baz,
This is the door lock from my RMC, you can cut through the fibreglass on the inside of the door to expose the back of the plate where the tap is broken. You might be able to get a grip on the tap from there.
Good Luck
Ross
|
07-04-2008, 06:05 AM
|
|
CC Member
|
|
|
Join Date: Mar 2006
Location: Perth,
WA
Cobra Make, Engine: G-Force MkII, Ford 429, Tremec TKO, Jag Suspension, Sequential LPG Injection, On The Road.
Posts: 35
|
|
Not Ranked
Hi Baz,
Have you had a win yet with getting the tap out ?
To add to the suggestions, a stud welder might be an approach worth considering.
Heavy machining/engineering firms, especially mining oriented ones use these.
It will allow you to reach into the back of the tap and should form a weld with a good surface area providing enough strength to back it out.
Cheers
__________________
Andrew
|
07-04-2008, 08:15 AM
|
CC Member
|
|
|
Join Date: Jun 2006
Location: Newcastle, Warners Bay,
NSW
Cobra Make, Engine: RMC . 393 Dart alloy block Stroked 351 alloy heads ..all the goodies plus a pre oiler. al
Posts: 1,495
|
|
Not Ranked
Quote:
Originally Posted by Philm
HI Baz,
I did something similar with an NPT tap into a brand new dart block.
I recon I lost 10ltrs of sweat when I realised what I had just done.
I grabed an old spanner and cut one end of and cut the center out, if you like made a 2 tine fork, the tines fit into the groves of the tap.
Then with plenty of tapping fluid and a gentle hand backed the tap out.
Phil
|
Aha a builder! You beat me to the punch. Once, a long time ago I broke a tap in a bad spot and sweated blood until I made a two pronged "spanner" out of an old screwdriver, hardened it and screwed out the busted tap. I thought I was just lucky.
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -7. The time now is 11:58 AM.
|
|