Removing stainless fasteners from an aluminum mast after 30 years

[Oldrig]

My plans to launch last week came to a screeching halt when I inspected the gooseneck on my vintage (1982) Cape Dory 25D. Because the spars had either been stored atop the boat or in the yard's spar shed until this year, I had never taken a close look at it before now.

What I saw scared the heck out of me: In three decades of wear, the cast aluminum boom toggle had worn deep into the lower half of the mast bracket, almost wearing through. And, the holes in the toggle were now oval instead of round.

After spending nearly an hour on the Rig-Rite web catalog, I was able to identify the parts and order them. Rig-Rite, a firm not known for its customer-friendly attitude, told me it would be "two to three weeks" before the parts arrived. I suspect they're being custom fabricated.

But I might need all that time to get the old bracket off the mast. It is attached to the aluminum with six heavy-duty stainless-steel screws (slot-heads). And, of course, the manufacturer didn't use anything like Teff Gel to protect the fasteners from corrosion.

When I posted this question on the Cape Dory board, several people cautioned that I'd probably have to drill out the heads and reposition the new gooseneck. I don't feel confident to do that myself, so I called a friend and freelance boat-builder and repairer.

He suggested repeated applications of PB Blaster, use of a manual impact driver and a 2-lb. sledge and, possibly, repeated heating and cooling with a propane torch.

I started applying the PB Blaster three days ago, and I've been tapping the gooseneck bracket, waiting a few hours and trying to budge the fasteners with my impact driver. So far, I've had no luck at all.

Should I get a reciprocating saw and cut through the cast aluminum bracket, exposing the screw heads?  Any other ideas?

Thanks ... I'm going crazy watching all those sailboats in the water already ... it ain't pretty to see a grown man cry.

--Joe :'(

[Tim]

Joe, I just recently removed some screws from the Ariel mast that were tough. I ended up heating them up and clamping  small vice grips onto the filed heads.

[rorik]

I think rushing to cut or drill them out is over rated.
The bolts will come out - eventually.
I had to pull mine out of the mast half of the gooseneck last summer (8 bolts) when I re rigged. Heavy doses of CorrosionX, impact driver and dead blow hammer, heating with a normal heat gun. Rinse, repeat, ad nauseum. After a couple of hours of that, they all came out.
It is a long, tedious, frustrating pain in the ass, but it will work.

[Captain Smollett]

The bolts will come out - eventually.

...

It is a long, tedious, frustrating pain in the ass, but it will work.

Indeed.

A few years ago, I took the brake drums off a truck.  The drums were essentially rust welded to the hubs.  Several cans of PB Blaster, judicious beating the dickens out of it (with a couple pound masonry hammer) and multiple heating/cooling cycles with a propane torch did the trick.

It took a couple of MONTHS, though.  Partly that was I worked on it around a lot of other commitments and partly it was to let the PB Blaster soak.  Just when I was convinced one drum would never come off, booop, it plopped right off like it had never been stuck.

One trick is to heat it then spray the penetrating solution onto the hot surface.  Be careful though; if you get it hot enough, it might flash (not likely if using a heat gun).  But, that helps to get the penetrate into the joint.

I've also seen (steel, not aluminum) parts needing to be heated to a nice red glow to break that corrosion weld...but it will break.  I had some real fun getting the engine out of a dump truck one time when that truck had spent a decade and a half on road salt duty in NJ. 

I generally do not like to drill/grind parts out.  For me, there is just too much potential to screw something else up.  But, I have been known to do it.

Good luck.

[Leroy - Gulf 29]

I had some well stuck stainless bolts in some cleats.  I tried the heat, gentle persuasion (BF hammer), etc. and failed miserably.  I then used pentrol, and my DeWalt impact driver.  That worked.  Didn't get the bolt completely out (twisted off though inside the cleat), so continuing the penetrol and a drift punch and succeeded.

[Oldrig]

\
It took a couple of MONTHS, though.  Partly that was I worked on it around a lot of other commitments and partly it was to let the PB Blaster soak.  ... One trick is to heat it then spray the penetrating solution onto the hot surface. 

Thanks for the tips, guys. Like John, I have other commitments, including commuting from my Cape Cod location to my home in central Mass. Also, I'll try heating the fasteners and spraying PBBlaster while they're hot. I was doing it the other way around, which doesn't necessarily make a lot of sense.

I'm really reluctant to do any drilling or grinding if I can avoid it. But those screw heads are getting a bit worn. >:(

--Joe

[Captain Smollett]

I'm really reluctant to do any drilling or grinding if I can avoid it. But those screw heads are getting a bit worn. >:(

--Joe

Hi Joe, I don't know how much room you have on the heads, but one trick that I've found to work when the heads get knankered up is to use a sharp cold chisel and hammer, tapping on the perimeter of the screw/bolt head in a manner that should turn it.  This is getting near "last resort" territory, though...it's going to tear the head up worse.

Sometimes, too, you can take a hack saw and saw in a slot for a screw driver, or as Tim mentioned, file flats on the perimeter to get vice grips or pliers on.

Stainless heads should be hard enough to get SOMETHING to get a bite...

Pain in the transom either way ...

[Godot]

When the head of a crosshead screw is starting to round out where the screwdriver is having a hard time getting a grip, try dipping the head of the screwdriver in some comet or other powdered cleanser. It should dramatically improve the drivers grip on the screw. Once it gets well and truly rounded, cutting a slot with a hack saw can work; but you may only get a couple tries at it before the head gets completely buggered. Sometimes drilling makes sense.

[Oldrig]

Thanks for the tips, guys. Unfortunately these are slot-headed screws, and they're slightly recessed in the fitting. Still, a cold chisel might help. I'll probably just keep using the PB Blaster and heat for a few more days. If no luck, I might try hacking away at the aluminum fitting to provide better access to the screw heads.

Any way you do it, it certainly is a pain.  ???
--Joe

[Oldrig]

UPDATE: I've been spraying the darn fasteners with PB Blaster (I even built a dam out of plumber's putty and fillet with the stuff), heating with a propane torch and using an impact driver with a 2-lb. sledge for days and days, and still no movement. On Sunday my friend Dom, a contractor, former furniture builder and much more substantial guy than I am, tried whacking the impact driver with the sledge--no luck!

I guess it's time to start grinding. Frankly, I'm nervous about this.

--Joe

[Frank]

Sounds like the ole addage:  "if that doesn't work....get a bigger hammer" won't even work here.
Good luck grinding. "slow n careful"

[marujo_sortudo]

If drilling through stainless, make sure to go slow and break often to let it cool off.  It work hardens with heat and becomes an absolute female dog to deal with if you go too fast.  You can also start with small bits and work your way up to get it centered.  If you're VERY careful, you might be able to drill out the center of a bolt and pick out the threads leaving the aluminum untouched.  So far, my record is 50/50 on that technique.

[ralay]

Did you ever get this fitting ground out?

We've been going through exactly the same thing the past few weeks while removing all our stainless fittings for touch-up painting.  Our gooseneck fitting slides in the mast track and was totally jammed and doing a real number on the aluminum.  I soaked it in PB Blaster and banged it for two weeks before JW could get it out with an impact driver.  We're going to replace it with a bolt-on type that is easier to isolate.  Anyway, sharing the pain of banging on a recalcitrant gooseneck fitting made me wonder if you'd ever had any luck swapping yours out.