Thursday, February 5, 2015

Anchors Aweigh

No, I'm not heading away just yet. But I am getting a step closer as I checked the anchor roller repair off the list today. Where I last left off with the story, I had just completed the fiberglass layup and was letting it cure before continuing work. With the weather issues, it has taken several days to complete this project.

After the fiberglass had cured for several days (long enough I hope it had bonded as well as it was ever going to), it was time to cut the excess fiberglass off to create the finished edge of the opening. Using the vibrating multi-tool I picked up at Harbor Freight a while ago, I trimmed the edge down even with the existing structure. I then sanded it to even everything out and make it look like it should.

Edge all trimmed, note how thick it is now.

Next, I needed to re-drill the mounting holes. In all but one case, part of the old hole was left behind so it was a simple matter to punch through the new layers of fiberglass (using a wood backing block helped to prevent splintering). Once those holes were in place, I temporarily mounted the roller so I could mark the location for the one new hole. After it was marked, that hole was drilled.

Originally, the anchor roller was mounted with simple fender washers to back up the bolts against the fiberglass. A better option, and one that may have prevented the failure of the fiberglass around the bolts in the first place, would have been a proper backing plate. So I decided I would do the right thing and I had a stainless steel backing plate made at a local machine shop.

Old backing versus new...which one do you think is better?

With new holes and a new backing plate, I decided it would be a good idea to test fit everything before I painted the new fiberglass. When fitting the backing plate, I noticed that a couple drips of epoxy were preventing the plate from sitting flush. I grabbed my Dremel tool, put on a small drum sanding bit, and removed the drips. The plate now sat flat. Of course, this was the point where my ring decided to go for a swim. Note to self: I need to make sure I remove jewelry, no matter how minor the project.

I had purchased some bilge paint to coat the new fiberglass in the anchor roller locker, but I guess I should have read the label better. Checking the label, it said it wasn't for use with epoxy without special primers and at the temperatures I would be working in, it said it would take two or three days to dry between coats.  I decided I would return the paint and use gel coat instead. It should provide good protection and won't have the same drying issues...or so I thought.

Proof the gel coat was mixed well.

I'm not sure what happened, but a couple small spots on the first coat of gel coat didn't cure properly. Even though I used finishing gel coat with wax, a few of the spots acted like the wax didn't work. What is it with waxed gel coat not always curing properly. I guess, in the future, I should just use laminating gel coat and plan to use poly vinyl alcohol (PVA) to seal the surface for the final cure. I ended up applying more gel coat to the problem spots and that did the trick.

Everything coated and ready to mount the roller.

After letting the gel coat cure, I used some sandpaper to clean out a few drips from the mounting holes and I was finally ready to bolt everything back together.  Once more into the dinghy (so I could work from below the locker) and with Bill's help I was able to get the roller mounted and the anchor back on the end of it's chain.

The Mantus back home where it belongs.

Everything seems very solid now, no movement of the roller bail at all even when I put all my weight on it. Between the added thickness of fiberglass and the new backing plate, I think the mount is significantly improved.  Hopefully it will keep the Mantus anchor secure for a long, long time.


  1. Nice job! That first photo really highlights how thin the original layup was, it looks much better now. The backing plate is great idea considering the amount of weight it will hold, and the vibration as the chain moves over the roller.
    Is that insert piece in last photo (next to the anchor) just to reduce the chance of things dropping through? I have not seen that before.

    1. Hey Alan,

      Thanks. Yeah, I've easily doubled the thickness of that rim and I think that aids the structure quite a bit...kinda like an I beam. The backing plate just made sense, I thought the fender washers were kind of silly.

      The function of that insert (the tray I first practiced can see the patch in the picture) I can only guess about. Your guess seems possible, or maybe it helps prevent an excessive amount of water from coming up through there in extremely rough seas...either that or they just wanted to make it even more of a challenge to attach the bridle during anchoring. Whatever it is, it is only 1/8 inch thick...including gel coat and paint, so it isn't very sturdy.