dingy davits

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Aug 25, 2008
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30670
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I am going to be installing dingy davits to my 2001 Carver 356, and would like some advice. The davits will be installed on the aft end of the standard plaform, but the problem is that I cannot get to the inside of the swim platform to use nuts and bolts. Any ideas on how to attach the davits?
 
If none of our fellow ROs have any suggestions, I might call these folks at St. Croix Davits:

http://www.davit.com/

About 6 or 7 years ago I did business with them and they were very nice, courteous and knowledgeable. Maybe they can help...
 
I installed St Croix 400/401 davits on my 1995 model Carver 325. I tried a hundred different ways to get under the swim platform. For that reason I put off the job until last year.

The only option is to cut out circles for inspection plates, as that is the only way you'll ever get to the underside.

Also on my boat, the swim platform is balsa cored. I was surprised; I thought it would at least have been plywood. At any rate, you need to seal the balsa with epoxy and also you need some way to stiffen the underside. Fender washers won't do it. I used 4" aluminum channel.

I was able to get the aluminum channel fed to the inside of the swim platform from the cabinet in the aft cabin. Of course your boat will be different, but the idea is to find a path.

Here are some photos.

No two ways about it, you need to cut a couple of big ol' holes in the swim platform. I even checked with St. Croix as they show several Carver Aft Cabins with their mounts on their web page, and this is how they did those as well.

ddinst1.jpg


Next, I taped off the holes (or it will show as I am sloppy), and I used West Epoxy to soak the balsa coring really good.

ddinst2.jpg


Here is the aluminum channel I made. I started out with 3" channel shown here, as that is the only stuff the local supplier had, but the hole pattern was such that I had to cut into the sides. There are 4 channels, one for each side of each support.

Also you'll want to ground the channels to the boat's ground. You can see the green ground wire that I attached to the channels. St. Croix recommends this, and I have no idea why other than to drain any galvanic corrosion away to the zincs.

You can buy stainless steel channels from St. Croix, but for some reason they recommended using aluminum channels in their instructions. Never did figure that one out.

At any rate, you must use something like the channels to have sufficient holding power. Fender washers would probably simply pop through the balsa cored swim platform.

ddinst4.jpg


This ended up weakening the channels, as they bent under pressure of tightening the davit mounts down, so I later found some 4" channel on-line of all places (about $100 for 4 pieces), and believe-it-or-not, was able to replace them with the boat in the water.

ddinst3.jpg


I did this job last year before I launched the boat. The boat is 100 miles from my house, and I setup my mini-machine shop in the back of my pickup. I used a chop saw as I had to shorten the aluminum channels a bit to get them to fit.

Of course, this was all for naught, as I indicated I later replaced the 3" channels with 4" channels after the boat was in the slip.

ddinst5.jpg


Here is the shot you are probably most interested in, it shows the channels under the swim platform, mounted to the dinghy frame. You can already see where the aluminum channels bent. As I said, I replaced these with 4" channels that were wide enough that the mounting bolt pattern fit inside of the channel.

ddinst7.jpg


You will also want to use a liberal amount of 4200 sealant to seal everything when attaching to the swim platform.

Sorry for the poor lighting, but you can hopefully see the deck inspection plates installed in the holes that I cut.

I kept the hole cutouts as one day, I might teak the deck, and if I do, I'll permanently attach the 4" channels to the underside with captive nuts, then put the inserts back in, under the teak decking... or at least that is what the admiral has on my list.

ddinst6.jpg


One issue I do remember is that it was a bit difficult to determine where to place the support cages. There are a few obstructions in the way in the swim platform (the recess for the boarding ladder for one), and the placement was a bit limited.

However, I was able to place the support cages so that I still have use of the swim ladder, and in fact, they become an asset as there is now a hand hold to help board via the ladder.

As it turned out, the spacing is just a bit wide for my dinghy. But the cantilever action of the mounts work perfectly and self-adjust to the dinghy.

However, my dinghy is only 9ft and something inches; which means.... maybe a larger dinghy is in my future.

The other thing I discovered, is that you have to get the dinghy right up as high on the davits as you can during boat operation, as the boat squats quite a bit underway, and the dinghy can actually hit the water as you go onto plane otherwise.

When the boat sits in the slip, we usually leave the stern end of the dinghy quite a bit lower than the bow, so that any rain water that collects will easily drain out.

And for some reason, the davits tend to become a Jungle-Gym of sorts for spiders. They seem to love it.

Hope this helps. I'll try to find a better photo of the deck plates.
 
awboater. WOW!!! Awesome information. I could not ask for anything more. Pictures and everything. Great!! I may now put off this project until the fall, and do it RIGHT, like you did. You should write instruction manuals for a living. Nothing left to the imagination. Thanks again. Trevor
 
if you dont need reinforcement, there are special things you can buy designed especially for your situation. i've seen relatively inexpensive ones in a hardware store and really expensive marine ones. it's kind of a wing-nut looking thingie that has long plastic sleeves on each side. on the other end is a platic collar. you drill the hole, insert the wing thingie sideways so it fits, then push down on the collar. it rides down the sleeves and seats itself in the hole. then you snap off the excess sleeve and you have a neat install.
 
Awboater, that is a superb install, pics and description. Can you give me a rough idea of what those davits run? Checked the website, but couldn't find prices, just need approx. idea. Thanks!
 
I bought my davits last year. I think I paid around $2K for the whole thing. Unfortunately, you don't get a price break for a package deal when you buy both (items #400 and $401). After adding the price of the rope, metal braces, hardware, dinghy pads, shackles, lift bars, and so on, I think I have about $2,500 in it. That stainless hardware isn't cheap.
 
Here is the best on-line price I found for them last year; for both #400 and #401. I ended up getting them at a nearby dealer (Wolfs Marine in Benton Harbor, MI) for about the same price.

http://www.waypointent.com/St-Croix_2.html

If you have a soft-bottom dinghy, you'll have to get some glue-on D-lift rings.

http://www.sailrite.com/Dinghy-Rings-Glue-On-2-Standard-Gray?sc=2&category=110684

And don't forget the glue: you need a different kit depending on if your dinghy is Hypalon or PVC.

http://www.sailrite.com/Glue-Kit-for-PVC-Boats?sc=2&category=110684

The two rings and glue will set you back about $150.

Then you will need some sort of lifting kit. I made mine, but if you buy one, its another $150 or so. But honestly, after I purchased all of the stainless hardware, I am not sure if I saved any money.

And even the lifting line, 100ft of the good stuff (i.e. Samson or other similar mfg), will cost $50 or more.

I found the aluminum channel on-line (www.discountsteel.com). I live in a small town without many resources, so I bought the aluminum from an on-line place that will cut to suit, and have no minimum order. There goes about another $100.

I bought 4 pieces of "Aluminum American Standard Channel 4" x .247 -- Length: 30" I took my chop-saw up to the boat, and I had to shorten one of the pieces a bit (the one that goes behind the steps).

Then you need bolts, 5200 sealant, and 6" or 8" inspection plates. That about kills a $2,500 bill.

By the way, its a bit of a trick to get the aluminum channel into the swim platform. I could not find how to do this without having those inspection plates in the deck.

But I was able to take the two removeable bottom pieces out of the rear berth's vanity. Open the vanity - better yet, take the doors off (they come off easily with the euro hinges), then lift the two plywood bottom pieces - they have those lifting buttons on them, and are about 4" x 18" each.

Its also a good idea to take the doors off the lower cabinet as well, and take all of the contents out.

Before you put the U channels into the swim platform void, mark and drill them by using the St Croix #401 platform mounts. Mark which platform mount you use as they are not exactly the same (at least mine were not), and the hole pattern will vary slightly.

Also mark which U channel goes to the left and which one to the right as the hole pattern is asymmetrical left to right.

I then used a nylon line and tied it to the U channel, so if I dropped it into the void, I could retrieve it. Same thing for all of your tools.

The channels then will fit into the swim platform void by inserting them into the lower cabinet under the vanity, holding them horizontal, and rotating them around the top edge of the rear of the cabinet. There is just enough room to get the channels into the space. If you can have a helper outside with their arm into the 6" holes you drilled into the swim platform, this job is a bit easier.

Also, St Croix recommends grounding the davits to the ships ground. They don't say why, other than to do so. I suspect the reason is that the davits become a handy hand-hold when boarding the boat.

Anyway, fastening a ground to one of the U channels for each support is a convenient way to do this.

Feel free to ask any installation questions. It has been a year since I did this, and I changed out the U channels from 3" to 4" while the boat was in the water, so I did gain some experience.

One thought. I have a poor-man's milling machine, which means I bought an end mill bit and chucked it into my drill press. I elongated the mounting holes, and removed part of the sidewall of the U channels as the bolts come awfully close to the edges.

If you don't do this, I would recommend trying to find a 5" U channel; or you can buy item 402SS from St Croix, which is a backing plate, but they are almost $300, which is crazy expensive.

bracket1.jpg


Here is a photo showing the original 3" brackets I used, and the 4" brackets I replaced them with. If you look at the side walls where the 6 holes are on the left side, you may be able to see where I milled into the sidewalls.

OK, the elongated holes didn't come out so straight, but it was good enough, and about the best I could do with a drill press and a made in China milling bit.

On the 3" mounts (bottom piece), you can see where I cut the sidewalls out to clear the bolts. This ended up weakening the channels too much, which is why I replaced them.
 
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