Rebuilding Spinnaker Pole

[Capt.Don]

I want to rebuild an old spinnaker pole. There are at least 4 things to do: (1) sand and LP paint the pole, (2) unfreeze one of the ends, (3) replace all the trip lines, (4) redo rivets holding the end.....

Repainting the pole and unfreezing the forespar end is where I'm stuck.

The pole looks to be old anodized aluminum that is badly corroded. I took 220 sandpaper and knocked down and smoothed out the raised corrosion (about 65% of pole). How is best to prepare the pole for LP paint? I read somewhere that I need to etch the pole and prime. Specifically, what do I need to do?

The pin in one of the Forespar ends is frozen. I am able to move it about 1/4" using a dowel and hammer. I've tried soaking in vinegar, using PB Blaster and Liquid Wrench. I'm about ready to try a bigger hammer or give up on the end. Any suggestions on how to free the pin? Can these ends be rebuilt? Best case I unfreeze the pin, but can I replace the spring?

Once I get the end working, I'll tackle the paint and rebuild. Rivets and trip line should be easy!
Thanks,
Don

[skipmac]

I had to rebuild the end of a pole and called Foerspar who sent a new pin and spring at no charge. Hare to argue with that kind of customer service.

To free the pin next step I would try is heat but don't get it too hot or you'll weaken the aluminum then apply force again, aka heat and beat.

When I overhauled my windlass I primed the aluminum case with Petit Alumaprotect, a two part epoxy primer. Been three years and still looks like new. Not sure if there's anything better out there but bet some one will chime in if there is.

[Capt.Don]

Thanks - I'll try heat. I also hadn't thought about replacing the pin/spring - I'll call Forespar!

[Hydra]

On my spinnaker pole, the pin on one end froze with salt when it stayed on deck (on the lee/wet) side for a few days. I used fresh water and tapping with a medium-sized hammer. I filled the fitting with winch grease to prevent water ingress but it didn't work well.

I solved the problem by replacing both end fittings. One was stuck inside the tube, I had to saw/hammer it off.

Alain

[Capt.Don]

I spoke with Forespar customer service - their recommendation is to soak in vinegar for 2-3 weeks. Replacement piston and spring are available. We'll deal with parts and paint if/when I can free the jaws!
As far as paint/primer, I'm going see if one of the guys will prime/paint for a few bucks.
Don

[Capt.Don]

I managed to get the pin out of the jaws. The pin is held in place by an a small cross-pin across the end. This was broken anyway, so I removed it. The spring was another problem. It finally came out in pieces. Fortunately, the springs are available from Forespar.

As far as paint - I decided to the let the local boat painter paint the pole. I priced out the supplies for 2 part acid, yellow primer, LP primer and LP paint, and we are talking over $200. He'll paint the pole for less.

Next question - to prepare for paint I removed all the fittings (several of the rivets were broken anyway). The ends and the trip-line fittings were riveted to the pole. Should I replace with aluminum or stainless rivets? Any suggestions on how long rivet to use (e.g., 1/4" longer than material?). If stainless, I'm assuming these should be coated to prevent galvanic corrosion.

Hopefully next week I'll put this back together!

[donradcliffe]

Originally Posted by Capt.Don

Next question - to prepare for paint I removed all the fittings (several of the rivets were broken anyway). The ends and the trip-line fittings were riveted to the pole. Should I replace with aluminum or stainless rivets? Any suggestions on how long rivet to use (e.g., 1/4" longer than material?). If stainless, I'm assuming these should be coated to prevent galvanic corrosion.

If you are joining aluminum to aluminum, use an aluminum rivet. If stainless to aluminum, you should use a stainless rivet--coat in silicon to minimize (prevent is too strong a word) corrosion. Your rivet length is about right for a 3/16" rivet, but you might go a bit longer for a 1/4" rivet. The end pieces may be put on with 1/4" rivets, which means you may need to borrow a bigger rivet gun.

[Capt.Don]

Thanks - I'm assuming the ends of a Forespar spinnaker pole are cast aluminum. If so, then here I'm joining aluminum to aluminum with aluminum rivets, which makes sense. I'm still a bit concerned about the loads on the end of the pole, which may warrant the stainless rivets. Also, aluminum rivets are much easier to set, which makes sense considering the material.

[Hydra]

Capt.Don
On my spinnaker pole, the loads on the ends are mainly in compression: the rivets only keep the ends in place, they don't support a heavy load. And the ends are cast white metal (not steel), so aluminum rivets are OK.

I suppose the loads are also in compression on your pole ends, so aluminum rivets should be strong enough.

Alain

[Capt.Don]

Just an update. I'm waiting for replacement spring and cross-pin needed to rebuild the jaws. In talking with Forespar, instead of rivets, they recommended using 1/4"-20 machine screws. I'm thinking this might be a good idea - thoughts? If I do tap this, the drill size for 1/4"-20 tap is 13/64" or #7. It should be pretty easy to drill out the holes on the fitting, tap. Just want to double check before putting the pole back together!

[skipmac]

Originally Posted by Capt.Don

Just an update. I'm waiting for replacement spring and cross-pin needed to rebuild the jaws. In talking with Forespar, instead of rivets, they recommended using 1/4"-20 machine screws. I'm thinking this might be a good idea - thoughts? If I do tap this, the drill size for 1/4"-20 tap is 13/64" or #7. It should be pretty easy to drill out the holes on the fitting, tap. Just want to double check before putting the pole back together!

Should probably use SS screws but coat them with Tefgel before assembly. Good stuff. Will isolate the dissimilar metals and lasts a long time.

[Capt.Don]

Originally Posted by skipmac

Should probably use SS screws but coat them with Tefgel before assembly. Good stuff. Will isolate the dissimilar metals and lasts a long time.

Yes - thank you!

[Jim Cate]

FWIW,

I've always used s/s machine screws to secure the pole ends... you may well want to remove one again someday (broken trip line, etc). And while Tef-Gel has a lot of fans, it's pricey and we've used either anti-seize or lanolin with success for years.

And since you are springing for nice paint, you might consider putting some leather around the pole where it will intersect the forestay... keeps it from getting all scratched up.

Cheers,

Jim

[Capt.Don]

Agree with everyone on the machine screws. I have the 1/4-20 tap and 13/64" (#7) bit ready to go. One thing I've been thinking about is coating the inside piston/spring assembly with lanocote. It was very difficult to get the piston out of the jaws and I had to dig the spring out in a dozen pieces. This might keep the assembly free from salt & corrosion.

[Stumble]

Don,

I don't like lanolin, or really anything on the springs. The problem is that everything I have tried winds up attracting dust, and results in a thick goo of what used to be lubricant, and crud.

For working parts like this I always stick with dry lubricants.

There shouldn't be much of a corrosion problem really. The ends are typically cast aluminium, with stainless (hopefully 316 springs and jaws). This can result in some small amount of galvanic corrosion, but unless you have a carbon fiber pole I have never seen galvanic problems with one. What typically binds jaws up is a mix of galling that can't really be prevented, salt, aluminium oxide powder (again inevitable from the oxidation of the alumiium parts), and whatever lubricant and dust get trapped.

Keeping the parts operational is typically just a matter of fresh water rincing, regular dry lube applications, and working the jaws regularly to prevent build up of crud.