Dave,

Glacial Acetic Acid is almost pure acetic acid. Any chemical supply house
will have it in small bottles. Be careful while handling it. Add acid to
water rather than water to acid when diluting. Et c.

Dave M.

On Wed, 30 Jul 2008 10:42:02 -0400, wrote:

On 30 Jul 2008 08:56:02 -0500, Dave wrote:

On Wed, 30 Jul 2008 06:58:45 -0400, said:

Vinegar is greatly diluted acetic acid. Something around 5% acidity. Acetic acid
can also be 20%, 50%,100%, or anything in between, all which might surprise you
with their effects on metals including stainless.

Where does one buy the higher concentrations? I'm looking for something to
apply to the aluminum stanchion bases in order to get loose the stainless
bolts securing the stanchions to the bases. Might the higher concentrations
of acetic be what I'm looking for?

I don't know. Have you tried PB Blaster, and a hammer driven impact
driver?

If you want to try a strong acid, use the stuff they sell for
dissolving barnacles. Just be very careful with it, and don't
accidentally inhale the fumes.

Hydrochloric, sold as muratic for cleaning mortar from bricks, and for
adjusting the acidity of swimming pools.

Casady

wrote:
Hammer DRIVEN Impact driver

Like this:

http://www.harborfreight.com/cpi/cta...emnumber=37530


When you strike this device with a hammer, it applies the impact, as
well as turning force at the same time. Very effective. Japanese
motorcycles used to have steel Phillips head screws holding on the
aluminum engine parts. This tool could get them out, even of the screw
heads were already partially rounded out from previous attempts.

Absolutely correct! Still have mine I bought in the '70s to pull the
screws out of my Kawasaki. Works like a champ.

Keith Hughes

wrote:
On 30 Jul 2008 11:48:01 -0500, Dave wrote:

On Wed, 30 Jul 2008 12:32:47 -0400, said:

Hammer DRIVEN Impact driver

Like this:

http://www.harborfreight.com/cpi/cta...emnumber=37530


When you strike this device with a hammer, it applies the impact, as
well as turning force at the same time.
Might be worth a try. I have one of those and have used it to remove some
tough fittings. Didn't occur to me that banging and twisting on the head end
might be more effective than trying to simply drive the bolt from the
threaded end.

It's not quite a substiture for a pnuematic impact driver, but when a
compressor is not available, it's a good alternative.

Sorry, I missed what the OP's use would be, but for slotted/phillips
screw removal, the hammer version is actually much more effective, since
the downward (or inward if you prefer) force will keep the screw head
from stripping. For hex/allen heads, I'd agree with you about the
pneumatics.

Keith Hughes

wrote:
On Wed, 30 Jul 2008 11:39:39 -0700, wrote:


wrote:

He's trying to free steel bolts from aluminum after 30 or 40 years.

Ahh...

We
are in agreement about the hammer driver vs. the pneumatic gun for
screws, although, when I had air available, I always tried each screw
first with the small air gun first, because it usually worked, and was
so fast. Recalcitrant screws got a follow-up from the hammer driver.
Occasionally a screw was so welded to the aluminum that the screw head
would twist and break off, but that thankfully didn't happen often.

No, but it happened *too* often :-) And 30-40 years ago, I couldn't
afford a compressor!

Keith

On 30 Jul 2008 14:33:05 -0500, Dave wrote:

On Wed, 30 Jul 2008 14:46:05 -0400, said:

He's trying to free steel bolts from aluminum after 30 or 40 years.

Not quite correct. The PO apparently removed the stanchions from their bases
each year when he covered the boat, and I also removed them from their bases
the year after I bought the boat. So it's been about 3 years since they were
loose. I'm surprised at how quickly the bolts became irremovable.

Tapping and patience often works with frozen bolts. Soaking with your
choice of a "rust-buster," then whacking repeatedly, coming back later
and whacking a bit more. Only loosen the nut enough to protect the
end threads from the hammer, and bang on that, not hard enough to
deform the threads so the nut won't come off. But even banging in the
direction of insertion provides corrosion freeing action.
Might work for you, but use due caution not to overdo it.
I've used the method with good success. Even works on recalcitrant
pipe joints, preventing smaller rusted pipe diameters from twisting
off in the joint.

--Vic