How to free SS bolt from corroded aluminum fitting

[coopec43]

Originally Posted by Jim Cate

Where do I apply to get double my money back when it fails to work?

Jim

But! But! Plenty of people (even technical people) swear by it.

[coopec43]

Originally Posted by coopec43

As I mentioned in an earlier comment I have the fitting immersed in three liters of white vinegar. It has been there for a week now and I am prepared to keep trying - time is on my side. Thanks

I just hooked up my small welder for a short while and there is something definitely happening as the vinegar is bubbling near where the shaft enters (red arrow) the aluminum fitting. But that may be of no significance I suppose.....

May be I should persevere with this idea?

This is roverhi's approach

Seized tang bolts in aluminum mast 14-05-2018

Jumper cable trick.
You might try the jumper cable trick. Hook jumper cables up to the battery as you normally would. On the other end put a bolt (1/4" x 2" bolt works fine) in the postive lead clamp of the jumper cable. Clamp the negative lead as close to the offending bolt as possible. Touch the bolt in the positive lead clamp to the head of the fastener. You set up what is essentially an arc welder. Will heat the fastener to a cherry red if left in contact long enough. It also gets the fastener way hotter than you can with a MAPP torch. It works really well to heat up just the area of the fastener and not burning up the surrounding country side like you do with a torch. Really the only way to get serious heat to a fastener if there is painted surfaces or plastics close by. Quench the heated fastener with penetrating oil. Try to remove the fastener with an impact driver, either manual or power. Repeat the process till you break the fastener loose. Other than using the trick to remove all the fasteners on a 44 year old mast, used it to get corrosion welded bolts out that passed through substantial aluminum castings on my steering.html" target="_blank">self-IRJDSUNE9932123321222xxeww-steering vane

https://www.cruisersforum.com/forums...st-201200.html

[captchetco]

Originally Posted by Boatyarddog

is the step still attached to the deck?
Is it off, but has a stuck bolt stud in it?
The process will vary with other possiabilities.
If the step is off, cut the shank(threaded end) off flush with a die grinder, or grind flush with the base.
Use a punch to dimple the cut end in the middle, the penetrant works even better if you shock the bolt repeatedly, hammer and punch, every day for a week or so, even less.
The vibration will allow the penetrant to creep down the threads, and dissolve the corrosion.
Then try to turn it, a little at a time back and forth if it's moving at all you'll eventually loosen it.
If that doesn't work, you'll have to drill it out, this can be tricky.
Using a small sharp drill bits , titanium bits, progressively drill a bigger hole down the shaft center.
Once you get to the size of the bolt, the side will come away from the hole, and you should be able to pound out the carcass.
It's always a difficult job and one that can be frustrating.
Have any pictures of what your working on so we can see better?
SHOCKING THE BOLT WORKS WELL.
Cheers,
SV Cloud Duster

I agree with the forgoing. I have found that patience is the best tool. Small amounts of heat to the bolt, then cooling with a good penetrant, I like "Blaster" will cause the penetrant to soak into the corrosion which will also break up the corrosion a little, then the back and forth motion tapping on the head of the bolt will break the bolt loose always (almost). Don't so much use force, cause its easy to twist of an SS bolt. just repetition a little heat, penetrant, back and forth, while tapping on the head. Rarely one won't come out.

[sailah]

Originally Posted by coopec43

It had crossed my mind that I should use a hole saw and cut the aluminum thread and then re-tap the hole. The hole saws I priced were diamond tipped meant for ceramics. I didn't find any carbide tipped saws but I'll look again. I suppose ideally the saw should be thin walled.

If I can't extract it using liquids and/or force I'll follow your advice. Right now I'll do an eBay search for a suitable hole saw.

Thank you for your advice.

I would, under 0.0% circumstances, ever hole saw something like this. Hole saws won't produce a truly round hole. The precision version of a "hole saw" is called an annular cutter or rotabroach. These are extremely expensive. Even mounted in a milling machine, hole saws are rough tools. You'd end up with a really large, sorta round hole that would require expensive taps to bring back to size with a threaded insert.

Keep going with the the low impact, patient methods you have been using. If you break the bolt head you can move to more advanced techniques. Just keep rocking that bolt head fore and aft like you were trying to free a truck stuck in the mud.

[coopec43]

Originally Posted by sailah

I would, under 0.0% circumstances, ever hole saw something like this. Hole saws won't produce a truly round hole. The precision version of a "hole saw" is called an annular cutter or rotabroach. These are extremely expensive. Even mounted in a milling machine, hole saws are rough tools. You'd end up with a really large, sorta round hole that would require expensive taps to bring back to size with a threaded insert.

Keep going with the the low impact, patient methods you have been using. If you break the bolt head you can move to more advanced techniques. Just keep rocking that bolt head fore and aft like you were trying to free a truck stuck in the mud.

I don't think I'll use a hole saw at this stage but if the bolt fitted exactly within the hole saw surely that would produce quite an accurate hole?

After seeing the video clip I'm more inclined to use heat from my big welder (if I fail to remove it using vinegar and moderate force)

My experience drilling bolts out I "end up with a really large, sorta round hole that......"

You come across as a person who knows something about machining metal but a quick look at your personal profile doesn't confirm that?

[sailah]

Originally Posted by coopec43

I don't think I'll use a hole saw at this stage but if the bolt fitted exactly within the hole saw surely that would produce quite an accurate hole?

After seeing the video clip I'm more inclined to use heat from my big welder (if I fail to remove it using vinegar and moderate force)

My experience drilling bolts out I "end up with a really large, sorta round hole that......"

You come across as a person who knows something about machining metal but a quick look at your personal profile doesn't confirm that?

Re my experience, I've been a tool junky my whole life. My machining skills came from building enduro motorcycles. I started with a 14x40 Enco Turn Pro lathe and TIG welder. Rebuilt a lot of very heavy old American woodworking machines (1000kg table saws etc). Worked in a large machine shop with a variety of manual and CNC equipment. In my home machine shop I have 14x40 lathe, Bridgeport 9x42 milling machine, Powermatic 1200 drill press, horizontal band saw, Brown & Sharpe surface grinder. Taught waterjet training at a local school. So while I'm not a professional machinist that earns his wages with my hands, I've done a lot of machining.

A basic hole saw requires an arbor and bit, in the US these are almost always 1/4" pilot bits. Yes you can run a hole saw without a pilot, basically a poor mans annual cutter, but they aren't rigid enough and will walk all over the place when you try and start the hole. You may get lucky and use the SS bolt threads to essentially act as the arbor. I would think the chances of something going wrong are fairly high.

I've never tried the welder to heat things, although I thought about it once when I had a frozen copper pipe. I have a Lincoln Precision TIG 185 that can act as a DC stick welder and read somewhere on the internet that old timers would use this trick to unthaw pipes. Unfortunately it would have taken a lot of cable to get my welder to the pipe so I waited for nature to do her job.

[rbthorson]

If a magnet will stick to the bolt, you might try an induction bolt heater. An induction heater will only heat the bolt. Limit each application as the bolt will over time heat what it is attached to by conduction.

https://www.amazon.com/Bolt-Buster-B.../dp/B00ATSL7VE

[skenn_ie]

I suggest that heating the bolt might crack the surrounding alloy. A butane torch, or an industrial heat-gun, focused on the alloy would be a lot safer. Also, cut the bolt in the middle so that you are only working on one lug at a time.

[coopec43]

Originally Posted by skenn_ie

I suggest that heating the bolt might crack the surrounding alloy. A butane torch, or an industrial heat-gun, focused on the alloy would be a lot safer. Also, cut the bolt in the middle so that you are only working on one lug at a time.

Did you see the photos of the aluminum fitting?

[coopec43]

Originally Posted by sailah

Re my experience, I've been a tool junky my whole life. My machining skills came from building enduro motorcycles. I started with a 14x40 Enco Turn Pro lathe and TIG welder. Rebuilt a lot of very heavy old American woodworking machines (1000kg table saws etc). Worked in a large machine shop with a variety of manual and CNC equipment. In my home machine shop I have 14x40 lathe, Bridgeport 9x42 milling machine, Powermatic 1200 drill press, horizontal band saw, Brown & Sharpe surface grinder. Taught waterjet training at a local school. So while I'm not a professional machinist that earns his wages with my hands, I've done a lot of machining.

.

I'm impressed!! [Sadly on all the forums we get the "armchair experts" who are always ready to give their vast amount of advice}

I could watch expert machinists all day using lathes and milling machines etc and I often spent hours with the local expert who always made me feel welcome.

I may have to resort to more brutal methods but I'll stick to vinegar and welder/heat just for now.

Thanks

[coopec43]

As I said before I have one of the bolts on the aluminum fitting completely immersed in white vinegar.

This morning I attached the welder to the fitting/bolt and immediately a puff of steam shot out from around the bolt. That would indicate to me that the vinegar is penetrating the thread.

Here's hoping!


Does vinegar dissolve aluminum oxide?
Vinegar does contain acetic acid so in theory yes, vinegar can dissolve aluminum if used in large amounts or for over extended periods of time

[Bigmarv]

Originally Posted by Crusty Joker

Sorry that was ammonia and bleach... produces the highly oxidizing agent Phosgene... or Mustard gas... Use very tiny amount to see if it will dissolve the bond produced by the electrolysis. Good luck and keep us posted. We have been where you are now. All of us have resorted to FORCE with varying amounts of success and failure. Good Luck and Encouragement!

For clarity, mixing ammonia and bleach is very dangerous. Haven't read the thread in full to see if anybody else has mentioned this, but it can easily kill.

[coopec43]

I completely immersed the bolt in vinegar for 12 days. Everyday I heated it at least three times (with the welder) and immersed it each time. I belted it with the hammer (not too hard) often as well.

The pole fuse blew out at the power pole. Could I have done that using the welder?

This morning I used the socket spanner to gently work it back and forward going bit further every time. I was going well I thought then the bolt head dropped to my feet: I had snapped it Of course I am going to have to drill it out so I have ordered a 7.1 mm L/H drill. If I have to go to a 10 mm bolt i don't think it is a big deal.

I now have the bolt at the other end soaking in a 50/50 mixture of ATF/acetone. I 'll leave that for a week or so and see if I snap the other one too.

[goeasy123]

Jeez. Reading this thread is like (as my old grandmother use to say) 'watching two sisters of mercy trying to pick up dog sh!t with knitting needles'.


Get a Helicoil kit of ebay, drill, tap and fit. It's a 5 minute job and you finish up with a better solution.... the way it should have been manufactured in the first place.

[sailah]

Originally Posted by coopec43

I completely immersed the bolt in vinegar for 12 days. Everyday I heated it at least three times (with the welder) and immersed it each time. I belted it with the hammer (not too hard) often as well.

The pole fuse blew out at the power pole. Could I have done that using the welder?

This morning I used the socket spanner to gently work it back and forward going bit further every time. I was going well I thought then the bolt head dropped to my feet: I had snapped it Of course I am going to have to drill it out so I have ordered a 7.1 mm L/H drill. If I have to go to a 10 mm bolt i don't think it is a big deal.

I now have the bolt at the other end soaking in a 50/50 mixture of ATF/acetone. I 'll leave that for a week or so and see if I snap the other one too.

Depending on how it snapped off, suggest you plunge down with an endmill to establish a flat. Then poke a starter hole using a center drill. If you just try to drill it out with a regular jobber length drill bit it's very easy to walk off center.

Something like this, start at 15:00

https://www.youtube.com/watch?v=lXmZB0vDxUI