Dissolving broken bolt with alum

Using a tip I read here, trying to dissolve a broken off bolt in my trucks intake manifold that the PO left for me. I would like to thank Kmoe and other members for posting this great tip.
The modeling clay looks ugly but it's holding the alum solution. Not sure how long it should take, or if I need to renew the solution. Will check on progress tomorrow evening.

 

I have tried this with no success. Not sure if I did it correctly. Even added hygenpoxide to help boost the process.

 

I did add a splash of hydrogen peroxide, I watched a video on YouTube that showed adding heat to the equation may speed up the process. I will check for any progress tonight, fortunately for me time is not really a factor.

 

I let mine set for about a week with a 40 watt bulb for heat, but did not work.

 

If the fastener is stainless this won't work. It does take time, and the solution should be fairly strong.

 

Interesting, I wonder if we are using the same ingredient. This is what I purchased.

It was about $8 on Amazon, not sure if it's what you are supposed to use. I don't think this is what you would find in the spice isle at the grocery store.

I do not believe the bolt in question is stainless steel, it was magnetic, but from what I was reading that does not necessarily rule it out.

The clay is still holding the solution so at least I did that part right. The solution turned a nasty yellow color so that leads me to believe something is happening. The broken bolt was protruding 1/4" above the surface, I decided to stick my pinky in there and I did not feel the top of the bolt though the clay may have had something to do with that. I went ahead and sucked out the yellow solution and topped it off with more of the solution I mixed up yesterday. I will go ahead and give it another 24 hours before removing the clay to get a good look at what's going on.

 

I got the Alum from the local Bulk Barn store.

 

Alum is potassium aluminium sulphate, or ammonium aluminium sulphate.
Typically bulk sellers and grocers won't list wether it's potassium or ammonium, since both are equivalent for the usual purpose.
Nitric acid is another chemical that will dissolve steel, but not aluminum. It's s bit more dangerous to handle though (and shold NOT be used in combination with, or after, or before, alum).

I think that some of the issue with failure to chooch is the solution strength hasn't been made clear (may fault here I think). You dissolve the alum in hot water until the solution is saturated.

 

Chooch! Someone has been watching AvE on YouTube

 

Ya (that's who jolted my memory about this being a thing that works), but that's not the first place I heard the word. I love how he blends ethnic slang in new and interesting ways. I'm a particular fan of his regular use of Chinook trade jargon; I grew up using it myself.

 

I stirred the alum into hot water until the water became cloudy which I believe was the saturation point. I just used a solo cup to mix it in and left it sitting overnight in my garage. Is the solution still viable, or does it lose potency over time? Should I mix up fresh solution?

 

It's viable until there are no more reactants available in the solution. Heat speeds up the reaction. The color change that you saw is from the iron being violently ripped away from the broken bolt.

 

Update: I finally got around to removing the clay today and it was still holding the solution, but no discernible difference to the bolt.

Double checked to make sure bolt was magnetic. Thought maybe I did not mix enough alum into solution, so I mixed more in until I got clumps floating in the water that would not dissolve. The solution now is the consistancy of maple syrup.

Tried rebuilding clay dam but no go could not get it to hold liquid. Maybe because of 30 degree difference in tempature from last time. Decided to try to epoxy a aluminum can to the intake like I seen the gentleman in the YouTube video use, but could not find one around the house. After contemplating for a while I thought I would try the solution on a known steel bolt before I go to the trouble of trying to seal an aluminum can to the intake.

Will check on progress on test bolt tomorrow.

 

Just to update this thread I left a random bolt sitting in the alum solution with no heat for a couple of weeks now with no discernible difference. I have since moved on to other methods of removal with no luck so far, though i have been too busy to spend much time on it.

I believe either I purchased the wrong type of alum or heat is a very important ingredient to the chemical reaction. I was trying to use it outside and in my unheated garage in 40°f temperatures.

 

Ancient thread but I tried this as well and it didn't work for me. No little mermaids. The avE video about alum no longer exists as far as I can tell.

 

I do know that AvE (among others) have had to remove some videos for language/content in order to keep their videos monetized (and in some cases to keep their channels). That may be why he removed that one.

It does work. But the variables have to be controlled.

Here is another method, but it's a teeny-bit more dangerous.
Don't be like the video maker and just talk about using PPE. Use PPE!

 

The safer and longer method, since the AvE video is gone.

 

Also note that there are commertial products that chemically erode steel, but they cost a bit more.

 

i found that it works for taps that have been broken off did not have any luck with a plain screw in a test. I did mine on the stove kept adding soluition. to about 16 hours.
I mixed the alum based on what internet said was saturation level

 

Another take. Watch to the end to see how he overcame the difficulties many of you (and I) have seen while trying this on the intake bolts.
https://www.full30.com/watch/MDIxNTM3/cannon-rescue-part-6-historic-cannon-build-series-guncraft101

I think a block heater would be the best choice for keeping things hot enough for the reaction to take place consistently.