Saturday, April 25, 2009

Begin forward sliding hatch replacement

The forward sliding hatch on a 1988 Gulf 32 uses teak rails as the guides for the sliding hatch. When new, it probably looked nice and worked well, but 20 year old teak starts to get brittle when neglected and the edges of my rails were cracking and broken in places. It was fine for inside waters here around the San Juan Islands and Georgia Strait, but you wouldn't want a large offshore wave crashing onto your bow.

Replacing the hatch had been on my mental list for some time, and so I've been taking measurements and pricing things.

I ended up going with a Lewmar Ocean 70 hatch, which should be a pretty exact fit. I read about other hatch companies, but either their standard models didn't fit my opening or I couldn't find a retailer for them. Price would be an issue too with some of them. Unbelievably, West Marine had the best price as they were having a huge sale on them. That, my friends, never happens. They even beat Defender and PY Yacht and Fisheries. Anyway, I order my hatch and what do I discover? It's used. Yes, you read that correctly. West Marine sent me a used hatch. They made good when I called and sent a new one that came: slightly damaged. Something had pierced the packing box and slightly scratched the acrylic lens. Oh well, I can live with that, since it'll happen soon anyway.

Removing the old teak rails has proved very tough. The screws holding it in are cheap little bastards with small heads that strip easily. Plus, they used 5200 to bond the teak to the coaming. This bastard is just not coming off easily. This is great, except that the top part of the teak that actually holds the hatch in place was brittle and cracked and broken. This bottom part that is so solid is sort of wasted strength, as the top is the business end. Anyway, here are some pictures of the carnage. I had to drill off the screw heads in many cases because they stripped. then it was a pry bar affair, pretty much. I'll have to do some modest fiberglass and gelcoat work, but nothing big. Once I get all this cleaned off, I can put on the new hatch, which should be very nice.

Reseating the steering pedestal

Hit a milestone with the reassembly of my steering system yesterday with the reseating of the steering pedestal. When first removed, I found that it had been seated with butyl rubber using a thin seal around the edge and a thick bulge just inside to prevent water intrusion even if something got past the lip. I decided it worked well for 20 years so I might as well stick with it. After drilling otu the bolt holes through the epoxy I began to put it all together.

The first thing was to clean all the corrosion of the SS bolts. The aluminum pedstal and SS bolts creates the problem. I saw the Edson now tries to sell aluminum bolts to solve this, and wants a crazy price for them when all it takes is a little Lanacote to solve the problem. I cleaned out the pedestal holes, lubed them up with Lanacote, put a bead of butyl rubber around the bolts and pressed them into the holes. Even though the lanacote will prevent the butyl rubber from sealing tightly against the pedestal bolt hole, it is all hydrophobic and will more than do the job. I couldn't be sure the butyl rubber would protect the bolt in all places from further corrosion and so took this step.

When pressed in, the butyl rubber squirted out nicely from around the bolt head. From under the cockpit, I could also reach up through the larger hole and press down the butyl rubber lip to the cockpit and get a good seal. Now I just need to reassemble all the pulleys and cables under the cockpit and check their adjustment. You can also see the upgrade to the far better pedestal guard feet. The original ones were plastic crap.

Wednesday, April 22, 2009

I love Butyl rubber for sealing!

I must sing the praises of butyl rubber here. When I replaced my pilothouse windows the original ones had been sealed with butyl tape and when I removed it, it was like new after 20 years. After reading about butyl rubber various places, I came to see how amazing the stuff is for certain applications. I've used almost every sealant known to mankind at some time or another, and none of them earn my love as much as butyl rubber.

Everywhere it has been used on Aeolus remained bone dry after 20 years in the Northwest. The stuff does the job impeccably. It sealed the steering pedestal to the deck for pete's sake, which means it was exposed to water under pressure, and when I removed the pedestal recently, there had never been so much as a drop of water to ever make it under the butyl rubber.

For applications where sealing is the only needed, and not bonding, it wins for me hands down.

1. It's sticky enough to stick to surfaces and prevent water from passing.
2. It lasts forever, I mean forever, and does not need replacing every X years like polysulfide. I've removed a lot of 20 year old butyl rubber from Aeolus and the stuff is like brand new.
3. It goes on, and comes off, without mess. NO mess. Polysulfide stinks and is a major mess.
4. It stores indefinitely and unlike tubes of polysulfide or silicone or polyurethane, doesn't go bad.
5. Last and least, it is fun to play with!

Note on plywood core rebedding

Just a note to say that all the books I read about rebedding hardware in cored fiberglass must assume the wood is balsa, because they always show using a bent nail to eat out the wood core to leave a doughnut of empty space that you fill with epoxy. Well, let me tell you, that on my Gulf 32 they used some high grade plywood as the wood core, and unless it is rotten, that stuff is as hard and solid as you would ever hope. There is no way you can chip it away with a bent nail, I've tried. I've even tried to eat it away with my Dremel tool but it's a pain and not very successful. It's just not worth trying. My solution has just been to drill the hole out big enough that when filled with epoxy, and redrilled at a smaller size for the bolt, a rim of hardened epoxy is left around the bolt to serve the purpose of preventing water intrusion into the wood.

Can't follow the books on this one!

Progress on steering system

I've made some good progress on the reassembly of the steering system over the past few days. This working full-time sure puts a kink in my boat project schedule. I reassembled the plate that holds the pulleys that guide the steering cables. There are four bolts that hold this plate under the cockpit floor. Previously, the bolt heads were not backed by washers, meaning there was little surface area. I decided to reassemble this system by adding large washers under the bolt heads to better distribute the compression forces. Everything worked fine and it feels really solid now. I tightened these bolts down pretty snug, but being careful not to crush the plywood sandwich of the cockpit floor. The bolts go through an epoxy tube (part of the purpose of taking everything apart and reassembling was to drill out the old holes, fill with thickened epoxy, drill to the bolt width to create an epoxy tube and thus prevent wood rot) and I sealed the bolt with butyl rubber, my favorite stuff.

I also drilled out the four larger holes that secure the pedestal itself. The bolts are about 1/2 inch and so my 1/2 drill bit doesn't expand the hole enough. I bought an 11/16 boring bit to expand the holes and refilled with epoxy. This will give a good 1/8 thick epoxy tube on all sides of the bolt, and provide the wood protection I seek. I think it also provides some compression resistance. While I have the pedestal off, and the epoxy made, I wetted the previously untreated plywood core with a film of epoxy to prevent any future water intrusion. Luckily, it had gone the previous 20 years without any water getting in. The pedestal had been sealed to the cockpit floor at the factory with butyl tape, again my favorite stuff. When I reassemble I'll do the same.

So far, so good, and boy it's nice to be digging into all this stuff and making sure it is solid.

Sunday, April 19, 2009

Removing, servicing and rebedding all steering related components

Today I took the plunge on a project I've wanted to do for a while. I've removed and rebedded most all deck hardware along the way for Aeolus, but had yet to really dig into the steering related equipment in the cockpit. This first photo shows the top of the pedestal taken apart.

My goal is twofold. For one, I'd like to take it all apart to make sure everything is solid, not corroded and in good shape. Secondly, I know the bolt holes were just drilled through the plywood/fiberglass sandwich and thus the wood is open to rot.

Taking the steering pedestal apart is fairly straightforward but with lots of small parts. The hardest part is lying upside down beneath the cockpit and removing the many nuts on the many bolts. I strongly suspect that putting things back together will be much harder than taking them apart, per usual. How do product engineers get away with designing so many things that are virtually unserviceable? This second photo shows the various holes for either the pedestal guard or the under-cockpit frame that holds the steering cable pulleys.

Anyway, today I removed all the above cockpit equipment, removed all bolts, drilled out all holes, and poured the silica thickened epoxy into them to cure overnight. Next I will be drilling the holes out to a smalle diameter for the bolts, and reassembling everything.

I was somewhat surprised to find no rot in any of the bolt holes. Good news, of course, as replacing the cockpit floor is evidently a dreadful job. The worst thing I found is that the large bolts holding the pedestal in place had thoroughly corroded with the aluminum of the pedestal base. I'll clean all that up and treat with Lanacote the way it should have been done originally. I don't think I've found any stainless hardware galvanically protected from aluminum contact on my Gulf 32. I suppose this is common to all manufacturers of old.

This last shot shows the epoxy in the holes. None of these shots show it, but the four bolt holes under the pedestal itself are being treated the same way.