Corded stainless bolts in cast aluminum

[scottgledhill]

I have two round cast aluminum instrument pods on my binicle that were bolted on with large stainless steel bolts. So far larger tools, various penetrants, and heat have failed to lossen the bolts. Your thoughts on how to remove them will be apreciated.

[robwilk37]

a pic would help...
im assuming the pods are painted and youve got wiring issues? the careful application of heat usually breaks the lock as the alu will expand first, but if the above is true then dry ice is the trick. try PB blaster first if you havent already.

[hellosailor]

Dry ice, crushed and mixed with alcohol so that it can be applied in a towel as a 'slurry' that makes the metals very cold very fast. Some caution is needed when working with that. Two or three cycles of freeze-then-heat usually can break any corroded bond.

There's also freeze spray in a can, sold in many hardware and auto stores although that's often out of stock.

Depending on how those bolts go through? Sometimes cutting off or grinding off one end and then pushing them out will do it.

[GordMay]

Greetings and welcome aboard the CF, Scott.

[roverhi]

You might try the jumper cable trick. Put a bolt in the postive lead of a 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 works really well as you are heating just the area of the fastener and not burning up the surrounding area 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. It also gets the fastener way hotter than you can with a MAPP torch. 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 self steering vane.

Having said the above, the hardest fastener to remove is not one that is threaded into aluminum but one that simply passes through an aluminum casting like cleats, etc. Getting the bolts out of the self steering casting took something north of 25 iterations, heating with the jumper cable and quenching with penetrating oil over many days.

[Lancerbye]

I have had good luck with this same problem using a hand impact tool. The hammer blows to the end of the tool plus the turning of the socket or screw driver tip seems to do the job.

[Tingum]

The best penatrating solution is a mix of acetone and ATF. But I agree this situation calls for the electric heat.

[groundtackle]

All good comments so far. I could add the TIG welding gives you a very controllable heat source. Nick finally got his 2 elec primaries off his cal 2-46 for regular service. Not expecting this...maybe he can add some colorful commentary.

[groundtackle]

Yup that was frustrating. Nothing was going to turn that screw. The winches were mounted by a California boat yard around 2000. The way they were mounted there's no way to get them fully apart for servicing without pulling them tight off the deck. Well I had an unpleasant surprise. Not only several screws frozen as they pass through the aluminum mounting plate with no real option to apply significant heat until it's off the boat. Finallly pried it off the deck and found out why that one wouldn't turn! Installer missed with first screw so they drilled it and put another on top making this impossible situation. I hate stuck fasteners!
Nick

[TheThunderbird]

There is a reason why rivets are used on Alu parts.

When not possible,chemical separation is a must or, bolt destruction by the drill

[groundtackle]

Originally Posted by TheThunderbird

There is a reason why rivets are used on Alu parts.

When not possible,chemical separation is a must or, bolt destruction by the drill

? translation required
ce

[Alan Mighty]

Originally Posted by groundtackle

? translation required
ce

Beats me.

I am still struggling with the 'corded' in 'corded stainless bolts'.

My usual English-Chinese dictionary suggested that corded bolts were bolts with striations or threads cut into or moulded onto their surface, in contrast to smooth bolts (e.g. clevis pin, rivets).

I tried Urban Dictionary (Urban Dictionary: corded).

I'm now in a worse situation, caught in a Schrodinger's cat situation, not being prepared to open the fridge door because that act might freeze the corded bolts into:

(1) the state that they will forever lack the capability to play lossy compressed audio files (mp3 protocol); or

(2) the state that forces the bolts to have striations or threads (in contrast to smooth rivets or clevis pins).

The horror.

[Djarraluda]

Originally Posted by Alan Mighty

Beats me.

I am still struggling with the 'corded' in 'corded stainless bolts'.

My usual English-Chinese dictionary suggested that corded bolts were bolts with striations or threads cut into or moulded onto their surface, in contrast to smooth bolts (e.g. clevis pin, rivets).

I tried Urban Dictionary (Urban Dictionary: corded).

I'm now in a worse situation, caught in a Schrodinger's cat situation, not being prepared to open the fridge door because that act might freeze the corded bolts into:

(1) the state that they will forever lack the capability to play lossy compressed audio files (mp3 protocol); or

(2) the state that forces the bolts to have striations or threads (in contrast to smooth rivets or clevis pins).

The horror.

Corded is an easy one. The "auto-confuse" function did not understand "corroded"!

Roger

[anacapaisland42]

"Mouse Milk" a very high quality penetrant used in aircraft maintenance, use for 4 or 5 days to let soak thru. Good with Al and stainless
Bill

Originally Posted by scottgledhill

I have two round cast aluminum instrument pods on my binicle that were bolted on with large stainless steel bolts. So far larger tools, various penetrants, and heat have failed to lossen the bolts. Your thoughts on how to remove them will be apreciated.

[scottgledhill]

Thanks all!