Does a fellow Austinite have a TAP REMOVAL TOOL that I can borrow??

Upon finally getting the sheared bolt drilled out of the bottom of my motor, I was re-taping the hole and the tap sheared in there! It is one of the holes that the oil pan mounts to.

I have tried a million things to get the tap out, but so far no luck. I read online that there are tap removal tools, it seems to be something the old schoolers all had. Unfortunately, Harbor Freight has not started carrying them! Does anyone have a tap removal tool that I can borrow. I live in central Austin and can come grab it from anywhere nearby. I should only need it for the day, so I will have it back to you the same day.

Also, does anyone know if not having one of the screws that holds the oil pan on will affect the performance of the 1970 350 sbc? Perhaps, if I could run it without that screw?

THANKS FOR YOUR TIME.

Cater Joseph
(512) 663.6007
caterjoseph@gmail.com

 

i would guess the oil pan would leak with a bolt missing, if it was tin one.

a cast pan could parobably stand to have one gone.......just my guess, though im an expert on braking bolts,lol

never heard of a tap removing tool, love to see it


skull

 

Look at either McMaster-Carr or MSC online catelog, either should have them. I'm guessing it's a 1/4X20? Good chance of getting it out if it is. The tool looks like a pen with little slidey things on the side that go down beside the flutes of the tap into the hole. They are specific for tap size. You are outta luck if it's a 3 fluted tap. I have excellant luck tapping the tap sideways a little to loosen it. Then use a hardened pin to turn the tap out. Maybe pointy needlenose pliers too. PATIENCE IS A VERTUE!

 

They seldom work in the smaller sizes - like 1/4".


There are some threads here on the HAMB about tap removal.

Best bet is to get a HAMB machinist involved.

Go to Social Groups and look for the Chipmakers Club.

You'll have to join, but no big deal.

Some experienced and smart guys there and they'll be able to help.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I made a 4-sided lathe tool block for little brother and broke a 1/4-20 tap off.

Dinked around with it off and on for about a year.

Finally gave up and sawed off one side then presented little brother with his new three sided tool block....

 

You try driving nails into the flutes, and then twisting the nails with pliers?

 

I have actually shattered them before with a punch but I can't say that it will work. Sometimes it does and sometimes it doesn't.

Without the bolt your pan will probably leak. If nothing works for you you could try taking a piece of square stock long enough to reach the next too holes and drilling it so you can lay it over the pan rail and hold it down with the two adjacent bolts. its a kind of backyard remidy but its doable.

 

I have run without one bolt and used rtv, no problem. If you can mig weld into a pile high enough to get vicegrips on you may be able to get it out. I have sucessfully gotten out bolts with the head broken off that way.

 

Thats what I would suggest as well.

 

I used to be a salvage rework mechanic for an aircraft engine manufacturer. A good tig welder can tig weld a stem to the end of the broken tap then tig weld a "t" to the end of the stem. Twist the stem back and forth with a good pair of vise grips.
Doing this and using some compressed air to blow out the small pieces of the tap if the tap is shattered is probably the least neandrathal way to get it out.

 

if its a high speed steel tap welding on it wont work. the weld will break off. the best thing to do is find a friend with a mill and drill it out with a carbide endmill. then remove whatever is left of the tap with a pick or something that fits in the hole. for a 1/4-20 tap i would use a 3/16" endmill. that should clean out most of the tap.

 

Thank you guys very much for all of the advice...please keep it coming! I am going to decide on a path tomorrow morning.

 

cutting torch, burn it out. If you do it quick it won't heat up the block much.

 

I know they sell reverse drill bits , thats always worked for me when bolts have broken off.

 

left hand drills are the best when it comes to broken bolts for sure but wont touch a tap. you have to use something harder than the tap itself or like squirrel said, burn it out.

when you machine a part, usually the last step is tapping the holes, and even then when a part it pretty much done and you break a tap in it, its often more economical to start over than to try and remove the tap and possibly still ruin the part.

 

Of course. If you aren't handy with a torch you might not understand that, but someone that knows can understand the concept. Just heat the broken nub to a glow, a quick blast on the o2 trigger to blow it out, might have to run another tap in to clean the slag out of the threads.

 

to burn it out, id reccomend a guy with an e.d.m. machine, rather than a torch


skull

 

Could you : Weld up the "broken tap bolt hole" in the oil pan. Then drill and tap a new hole into the oil pan and pan rail about 1/2 in. away from the edge of the original hole. Too bad nobody makes a portable EDM machine.

 

Like Skullhat said, see if you can find a machine shop that has an EDM type tap disentegrator (sp?). Almost guaranteed to not mess up the threads. I have gotten many out also using a carbide end mill but you must mount the block in a ridgid milling machine.

 

that would work. you wouldnt even need to go that far away from the original hole. id say 5/16"-3/8" away would be sufficient assuming you have a way to drill into the block straight.