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godtool
01-23-2010, 09:27 AM
Heres some rambling for you. Took a pic to put in the carnage section but pic was not focused... so put my story here...

My 1976 dana 44 under the front of my 3/4 ton gmc plow truck has mile marker hubs. The lock tabs looked useless so I d id not use them and ended up tightening the bolts every trip or job. Finally I let it go and 4 cap screws broke off in the steel hub. I got 2 out with easy outs. The other 2 I have yet to get out. One I drilled and tapped with a 5/16" tap and the last one I broke the 5/16" tap off in the hole. Why you ask am I using a 5/16" tap to get the broken 3/8" bolt out? Well. I though I'd use 2 5/16" bolts to hold the locking hub on till I had more time to extract the broken bolts. So now I'm stuck with this broken tap in the hole. I see I can buy a tap extractor but would that really work? I figure try to burn it out but taps are brittle and I've smashed out a couple in the past. Then I remember I got my die grinder so I figure I'll go to Lordco today and buy a loooong bit to grind the tap out?? I thought of jb welding a couple studs in the 2 holes or even welding a couple studs in the 2 holes I messed up. Also the mile marker locking tabs, I wonder if I can get a larger set since the other ones looked to small to be of any use. So what are my options? I figure die grinding out the tap and getting the old 3/8" brken bolt out may take a day, lol. Welding a couple studs in will take a couple minutes. A tap extractor proably costs a mint plus the tap is in there about an 1" and jammed cock eyed in the hole and jammed against the "steel" of the hub since I drilled my hole off to one side... yes I did not use a 1/16" bit when I knew I should have. I center punched it and rushed, yadda, yadda... so now what.... its just a slow speed offroad plow truck... I think welding a couple studs in is the easiest....

Apathy
01-23-2010, 10:19 AM
tap extractors do work. but make sure you take your time.

if that doesnt work, what ive done in the past, is... ready for it,, it sounds wrong.

get a torch, concentrate the heat directly on the tap till its glowing red.

get your squirt bottle and spray the glowing red tap.. becomes extremely brittle.
get a punch and smash it.. it will shatter. You might have to do this a couple of times.

after its all dug out, chase the threads out.

I've done this a couple of times. and worked each time.

bakelite
01-23-2010, 02:49 PM
Old SCHOOL![36] :respect: Jeremy.[cheers]

Trooper
01-23-2010, 03:13 PM
Get a carbide drill and drill it out. I Dont like the hit the tap way seems to really fuck up the thread and you will most likely have to heli coil. If you can center the carbide drill into the tap you will have no problem.

godtool
01-24-2010, 08:13 AM
Carbide drill bit will drill out a tap? A tap only HSS? I'll see if Lordco's got one. If that don't work, then the welder will... maybe I'll try the torch idea too:D Thanks for all the tips...

nebowe
01-24-2010, 09:08 AM
tap extractors do work. but make sure you take your time.

if that doesnt work, what ive done in the past, is... ready for it,, it sounds wrong.

get a torch, concentrate the heat directly on the tap till its glowing red.

get your squirt bottle and spray the glowing red tap.. becomes extremely brittle.
get a punch and smash it.. it will shatter. You might have to do this a couple of times.

after its all dug out, chase the threads out.

I've done this a couple of times. and worked each time.


Yup this works...pretty good too

cowboy-truck
01-24-2010, 11:21 AM
Get another hub and set your locking tabs this time......

bakelite
01-24-2010, 01:18 PM
Get another hub and set your locking tabs this time......

burn.........[15]

Apathy
01-24-2010, 01:21 PM
carbide drill bit MIGHT drill it out,but doubtfull. and if it doens't work your out 30 bukcs for a drill bit

Trooper
01-24-2010, 01:54 PM
carbide drill bit MIGHT drill it out,but doubtfull. and if it doens't work your out 30 bukcs for a drill bit

Carbide will drill it out if he has a good hand. I drill HSS taps out all the time with carbide. I will usually machine a centering sleeve makes it allot easier. They just dont like vibration if you break the carbide you are compleatly fucked and will be griding with diamond for hours to get it out.

Get a micro100 carbide bit if you can afford it. you will want a centering/ spotting bit. Spades work well too if you can mount the drill

godtool
01-25-2010, 08:17 AM
Stores in town only had a cobalt drill fotr $20. No one has heard of a carbide drill but fab shop were not open sunday. Cobalt drill lost its edge. Torch did not work. Going to buy some wee little drills today. Mechanic buddy told me a carbide die grinder bit will most likely not work. My die grinder, grind bit worked until it disenegrated. Going to take hub off and drill wee little holes beside tap since its off to one side. Maybe drill through back of hub. I'm cheap and got time but a dana 44 hub is probably cheap too:D I'll try to get a pic.

godtool
01-25-2010, 08:18 AM
Cowboy-truck, post a pic of how the tiny tabs are supposed to work please

Apathy
01-25-2010, 09:22 AM
you can probably get a new hub for the same price as a carbide bit... seriously
and the cobalt won't even touch a tap.

godtool
01-26-2010, 08:00 AM
I figured finding a hub up here may be difficult and I just wanted to fix it quick. Parts guy in town told me to try melting tap out with small tip on cutting torch. Also said letting tap cool slowly will soften it so it can be more easily ground out. There is room beside tap to drill a couple small holes less than 1/8" so I'll try that first to loosen tap... Figuring the time and few bucks I paid for the cobalt drill and little wee drills yesterday could have called the wrecker for a hub...

Always broke
01-26-2010, 09:17 AM
Ok i got some thing for ya get about a three pound ball peen hammer hit it about a dozen times ........


















That won't get it out but it will make you feel better when you go to the wrecker to get another one !!!!! Haha

godtool
01-27-2010, 10:46 AM
I heated up the tap tried to blow it out. Then let it cooled down. Drilled around tap 3 holes with 7/64 bit and broke bit off in 3rd hole:mad: . Took die grinder bit ($25.00) and it ground it out until I was able to punch the tap to back of the hole. Helicoiled it:) .

http://i65.photobucket.com/albums/h213/godtool/DieGrinderBit.jpg

Tapped out all remaining hioles. Put grade 8 ready rod to bottom of each hole, put tabs on, and nuts. Bent useless little tab:( over side of nut with so nut cannot turn backwards. You may think I bent wrong part of tab but this was the only way the tab would not turn backwards. If this not work, then I'll make some REAL tabs... Thanks for all the pointers. All in all money put in...

25/64th cobalt bit 20.00
Carbide die grinder bit 25.00
Wee little drills 15.00
Total 60.00 and way too much time....

Stll have all the drills except one and the die grinder bit is still sharp. And the truck does not more *&^%^&* jaring when I put it in gear. So far so good...

http://i65.photobucket.com/albums/h213/godtool/MMTabs.jpg