Clogged tap on the wrong side of aluminum

[matthewsx]

Good thing about the Dremel is if you can't get the aluminum off you are already there with the tool to cut the tap

John

 

[Firstram]

I'm notoriously sloppy.

Buy a pound of lye from the hardware store, mix it in a metal cup and lay your part across the top with the tap submerged. Back the tap out in a day or two, profit!

 

[ChazzC]

Dental pick

 

[Inferno]

These are really good taps so I'd rather scrap the part than to cut off the top (Even though it makes a god bottoming tap at that point).
I went looking for the dremel and saw my mini hacksaw. The blade is narrow enough to get between the threads so I opted to try that. I got the bulk out and then scraped the best I could with a utility blade.
I am 99% sure I didn't damage the tap and I was able to back the tap out, mostly by hand. This will be my spare clamp and if I really needed it, I could always chase it with an 8mm if the threads don't hold.

I'm going to get some NaOH to finish cleaning the tap.
From now on I won't tap so deep without oil.

FWIW, usually I have residual oil from drilling which lobes the tap but this time I was going for speed and barely used oil while drilling. My drill bit seems fine but it was careless of me to go that route.

 

[WobblyHand]

Buy a pound of lye from the hardware store, mix it in a metal cup and lay your part across the top with the tap submerged. Back the tap out in a day or two, profit!

Not an aluminum cup! Or you will have quite a mess to clean up. Stainless might work, but I leave that to the chemists to look up. Glass would work.

 

[Firstram]

You

Not an aluminum cup! Or you will have quite a mess to clean up. Stainless might work, but I leave that to the chemists to look up. Glass would work.

You're right, steel, stainless, plastic or glass, the wife needs new measuring cups anyway!

 

[Inferno]

I'll just use one of my beakers. If it were to get ruined (highly unlikely) I'd just toss it. I have several hundred more.
Or, for something so small, I could use a test tube. I have over 1000 of those.
Or one of my, more than 100, graduated cylinders.

 

[RJSakowski]

Stainless, polyethylene, and polypropylene are safe to use with lye solutions of any strength. Lye will etch glass although slowly. As long as you aren't concerned with a minor amount of etching, you can use glass as well. If mixing lye with water, a large amount of heat is generated. The best way is to add lye slowly to the water while stirring. Cooling the solution in a cold water bath helps to keep the heat down. When I worked as an analytical chemist, I used to mix up five liters of concentrated NaOH solution on a regular basis. Wear PPE, especially a safety shield. to protect your eyes and face. Lye solution will readily dissolve skin.

 

[Dyspnea]

Why not use a 6mm nut and thread it on the backside. Might clear the chip.

 

[Inferno]

Why not use a 6mm nut and thread it on the backside. Might clear the chip.

I did try that and the nut wouldn't go. I think, if anything, it made it worse.