Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 01-06-2022, 05:27   #1
Registered User

Join Date: Jun 2019
Location: Rochester, NY
Boat: Chris Craft 381 Catalina
Posts: 3,687
Installed my new davits, thoughts?

My new davits arrived from Garhauer last week. Got them mounted, but haven't tried them out yet (dinghy is still at the house pending me finishing a few jobs on it).

They ended up taller than I was expecting, as I mounted them about 10" higher on the boat and at a slightly different angle. I originally planned to put the bases on the transom, but determined that wasn't going to line up well (stern rail leans in too far and other factors), so I put them on the deck instead.

I also still need to relocate the flag pole, although not all that much. I don't think we'll realistically lift the dinghy much above the top of the stern rail and instead just secure it at that height. The hardware I bought before figuring out the davits would be up higher should work (taller pole and straight base instead of angled). That should let the flag fly over the top of the dinghy and just clear the cross bar on the davits.

My only slight concern is flex in the stern rails. Even with the added braces to the swim platform, there's some flex if I push on the davit arms. But I'm not sure if it's actually a problem, as it's not a ton. And when I stood on the swim platform and pulled down on the lifting lines, there didn't seem to be any noticeable flex.

I'm thinking I may want to add some more bracing, but I'm not quite sure how to best do it. Any thoughts on that part?
Attached Thumbnails
Click image for larger version

Name:	PXL_20220525_222004553.jpg
Views:	191
Size:	432.7 KB
ID:	258733   Click image for larger version

Name:	PXL_20220525_222013517.jpg
Views:	216
Size:	450.0 KB
ID:	258734  

rslifkin is offline   Reply With Quote
Old 01-06-2022, 05:51   #2
Registered User

Join Date: Mar 2022
Location: Ontario Canada
Boat: Jeanneau SO 389
Posts: 1,407
Re: Installed my new davits, thoughts?

Looks like you need an engine mount and a pulley to hoist the motor.
On 3 power boats I had my Dinghy clipped and swung up on the swim platform. I didnít have an aft cabin window to obscure though. I have similar but shorter Davits and use my port electric windlass to pop the Dinghy up. Personally I donít like them. Stress on the glass drag on race day great for cruising I did have a 330 SeaRay Dancer with twin 502 hawks which could top out in low 50ís with a Dinghy folded up like a drag shoot because it was tucked tight on the transom.
Rumrace is online now   Reply With Quote
Old 01-06-2022, 06:03   #3
Registered User

Join Date: Mar 2022
Location: Ontario Canada
Boat: Jeanneau SO 389
Posts: 1,407
Re: Installed my new davits, thoughts?

My favourite Davit is the retractable model available on the Jeanneau 440 and up. First on the 54 they caused stupid place to put plywood problems in the quarterbirth. They since worked out the draining bugs
It’s one of the features which makes the 440 a touch better than the modestl faster 410.
Rumrace is online now   Reply With Quote
Old 01-06-2022, 06:10   #4
Registered User

Join Date: Jun 2019
Location: Rochester, NY
Boat: Chris Craft 381 Catalina
Posts: 3,687
Re: Installed my new davits, thoughts?

For the moment we're rowing, so no engine concern. But when we do put an outboard on, I sized the davits to handle lifting the dinghy with the outboard still on it. I'm not planning on a huge outboard for the dinghy (which is a pretty easily powered aluminum skiff), so we're only talking about an extra 55 lbs or so for a 6hp on the dinghy transom, plus some weight further forward in the dingy for fuel. The dinghy is about 150 lbs empty, so I figure with a 6hp, full 3 gallon tank, oars, and a small anchor left in the dinghy, total lift weight should be just about 250 lbs. The davits are rated for 400-ish if the stuff they're attached to is strong enough.

I'd rather avoid having to pull the engine off the dinghy every time, mostly for ease of use. It'll be lifted high enough (and on a powerboat, so no heeling) that I'm not worried about dunking the outboard or other stuff like that which would require removal.

For some perspective on lift height, the aft deck is about 4 feet above the water, the rail is another 29.5" tall above the deck. So if we lift the dinghy just above the top of the rail, the bottom of the dinghy will be a bit over 4.5 feet off the water.

We're not bothered by obscuring that window, as we never open the curtain on it anyway. And until we removed them, the boat had paneling along the aft rails like the stuff on the upper deck, so we're used to having no view out of that window regardless. I did debate the flip up davits (and we carried the dinghy tipped up onto the platform on fenders and tied down a few times before the davits), but I hate having the transom blocked (both for the name and the stern light). The biggest priority with sizing the davits was to be able to lift the dinghy so the lowest point was above the aft deck.
rslifkin is offline   Reply With Quote
Old 01-06-2022, 06:25   #5
Registered User

Join Date: Mar 2022
Location: Ontario Canada
Boat: Jeanneau SO 389
Posts: 1,407
Re: Installed my new davits, thoughts?

That sounds perfect. I canít recommend the YAMAHA 4stroke 4hp LOUD ENOUGH!
Great motor 65 pounds. You can buy a motor for 200$ less but run perfect for 20 years - Yamaha.
Iíve seen a flag pole with a funny custom curve to dodge the Dinghy and used to secure the Dinghy.
Looks great and a nice application for an aft cabin perfect. Iíd still sling the engine separate. The Nylon mount is not too ugly.
There is a little swim platform mount but soaks the engine. The Yamaha can lay down front or starboard side only. Even then it can foul a plug with oil. The range with just the on board tank is great and it comes with a 2 gallon tank hose bulb. The down side of Yamaha is they leave buying the right part youíre fault.
Rumrace is online now   Reply With Quote
Old 01-06-2022, 06:37   #6
Registered User

Join Date: Jun 2019
Location: Rochester, NY
Boat: Chris Craft 381 Catalina
Posts: 3,687
Re: Installed my new davits, thoughts?

Fortunately, the stern rail leans in enough that a vertical flag pole mount (instead of the angled one shown in the pictures) will keep the flag pole clear of the stern rail, but still inboard of the davit arms (and therefore clear of the dinghy). So that's an easy one to solve.

I haven't actually picked out an outboard yet (may not happen until next year), but it's pretty much between the Tohatsu 6hp, the Yamaha 6hp, or maybe the Suzuki. No point in spending extra on the Merc when it's just a Tohatsu on the inside. And the Tohatsu does have one feature I like and is hard to come by in that size: no internal fuel tank (I'm not planning to use it, so no reason to have it and the slight extra complexity). With a 3 gallon tank in the dingy, we shouldn't have to worry about carrying fuel for it separately, it'll just be a matter of topping it off as needed when we stop by a fuel dock for a pumpout, etc.

Ultimately, a decision on which outboard to buy may end up coming down to a combination of price and what's actually available when I go to buy (vs one I may have to wait 6 months for).

Once we have an outboard and put the whole setup together, we may still decide to carry the outboard separately. But being that the davits are sized for it, I'll at least see if everything works well to keep it on the dinghy when lifted. It'll be nice to be able to just pop the plug in, lower the dinghy and go (provided keeping the outboard on works well enough). In our case, the boat is a little heavy on the port side, so as long as we lift the dinghy with the transom to starboard the extra weight on one end of the dinghy won't be a problem from a balance perspective. And that's the stronger side of the stern rail assembly anyway due to the transom ladder placement.
rslifkin is offline   Reply With Quote
Old 01-06-2022, 19:52   #7
Senior Cruiser
 
Madehn's Avatar

Cruisers Forum Supporter

Join Date: Nov 2014
Location: Kemah Tx
Boat: Gulfstar 51
Posts: 402
Re: Installed my new davits, thoughts?

I think you might want to look at some X bracing between the two Daviits at the top. Also perhaps some bracing from the side toe rails up to about 18 inches up on the vertical of the Davit. These proved necessary on my boat to increase lateral stability in wave action. Just my two cents. Maybe try first to see if needed
Madehn is offline   Reply With Quote
Old 01-06-2022, 21:16   #8
Nearly an old salt
 
goboatingnow's Avatar

Join Date: Jun 2009
Location: Lefkas Marina ,Greece
Boat: Bavaria 36
Posts: 19,942
Images: 3
Installed my new davits, thoughts?

I once owned a boat with a similar deck layout, itís a bad idea to brace davits using the handrail , the whole arrangement looks very flimsy to me

Davits need to be braced down to the transom so that the handrail and more importantly the davit deck mounting are not subject to any movement.Click image for larger version

Name:	IMG_1654144585.379434.jpg
Views:	66
Size:	87.7 KB
ID:	258793
__________________
Interested in smart boat technology, networking and all things tech
goboatingnow is online now   Reply With Quote
Old 02-06-2022, 04:40   #9
Registered User

Join Date: Mar 2008
Location: On Barnegat Bay in NJ
Boat: Hunter 40.5 and C+C36
Posts: 200
Re: Installed my new davits, thoughts?

I also think the davit structure looks too flimsy. I suggest adding diagonal, SS, tubing attached to the transom as low as possible without interfering with the dinghy when hoisted. I suggest removing the dinghy engine while hoisted unless you are at anchor or in very calm waters. My solution was to have a hoist to lift a 15 HP, 2 stroke @ 75 lbs. With it I could plane with 3 adults. A dinghy is wet unless you are planing. With 6 HP only one person can plane. 90 % of the time I dinghied short distances and therefore I also carried a 2 HP, 2 stroke (later a 3.3.HP Mercury 2 stroke) which I could lift with 1 hand. Even the 2 HP was on the stern rail while under way.
j.g.evans is offline   Reply With Quote
Old 02-06-2022, 05:55   #10
Registered User

Join Date: Jun 2019
Location: Rochester, NY
Boat: Chris Craft 381 Catalina
Posts: 3,687
Re: Installed my new davits, thoughts?

As far as planing and engine size, the dinghy in question is a 12 foot aluminum skiff, not a RIB. They plane pretty easily and from what I've been able to confirm, a 6hp should plane 2 adults (not sure if it'll plane 2+dog). It won't plane the thing fully loaded, but any time we're carrying that much we're likely to be either in an area where it wouldn't be appropriate to plane anyway, or we're just not going far.

I did some testing on lateral support and they seem very solid in that department, at least from a twisting perspective. The existing cross brace seems adequate for that purpose. The only direction I can produce any flex is the stern rail flexing aft, although it doesn't flex very far. I'm expecting I'll tie the dinghy off to the stern cleats after lifting, so that will reduce the amount of lateral motion the davits themselves have to support. As far as sizing and strength, the davits and cross brace are 1.25" tube, the stern rail and supports to the swim platform are 1" tube.

I'm going to see if I can adjust the support struts running down to the swim platform slightly to pre-load the rail inward a little bit and see if that reduces the bit of flex before they seem to really take the load. I did confirm before launching the boat this year that the corners of the swim platform and the brackets there don't flex at all if I hang ~175 lbs off them, so the load from the support struts should be handled fine.

I'm thinking I should add some more support in the fore/aft direction, but I'm questioning the best way to do it. I could easily tie the platform support struts to the deck, but I think they may just flex too much for that to gain anything. On the port side, I could attach the ladder to the transom to reduce flex a bit, I'd just have to figure out appropriate fittings.

Any thoughts on where to best add fore/aft support in the setup? Keep in mind, as far as load goes, I don't plan to lift the dinghy all the way to the top of the davits (which will reduce the lever arm of the load). I'm planning to get the top of the dinghy a few inches above the stern rail, putting the bottom of it about a foot above the deck.
rslifkin is offline   Reply With Quote
Old 02-06-2022, 06:40   #11
Registered User

Join Date: Nov 2016
Location: Melbourne Beach / Fl Keys
Boat: Pursuit 3070 Sold / Cape Dory 28 FBT
Posts: 137
Re: Installed my new davits, thoughts?

How about you make two struts that go from mid/upper davit down to a mount on the aft cabin . Yes that will block your walkway under way but put a pin mount at the cabin side and just pull the pin and let the strut swing down next to the davits when not in use. I am looking at doing something similar only going up to my deck cover frame. Tree is kinda in the way but I think you can see what I'm talking about.
Attached Thumbnails
Click image for larger version

Name:	Cape Dory rear view.jpg
Views:	34
Size:	452.4 KB
ID:	258823  
endlesspursuit is offline   Reply With Quote
Old 02-06-2022, 07:00   #12
Registered User

Join Date: Jun 2019
Location: Rochester, NY
Boat: Chris Craft 381 Catalina
Posts: 3,687
Re: Installed my new davits, thoughts?

Quote:
Originally Posted by endlesspursuit View Post
How about you make two struts that go from mid/upper davit down to a mount on the aft cabin . Yes that will block your walkway under way but put a pin mount at the cabin side and just pull the pin and let the strut swing down next to the davits when not in use. I am looking at doing something similar only going up to my deck cover frame. Tree is kinda in the way but I think you can see what I'm talking about.
That's an interesting thought. I'll have to do some measuring to see if there's a practical enough way to do it (without making docking unsafe, as I need to be able to get from the helm to the side decks via that aft deck). I actually had the thought that if I hard top the boat at some point (it's in the eventual plans), I could run stays from the aft corners of the hard top to the outer ends of the davit arms to take some load.
rslifkin is offline   Reply With Quote
Old 02-06-2022, 08:09   #13
Registered User
 
SV__Grace's Avatar

Join Date: Dec 2019
Location: Currently cruising PNW
Boat: Nauticat 43 ketch
Posts: 703
Images: 5
Re: Installed my new davits, thoughts?

I have "off the shelf" davits that are similar to yours and they seem designed to be attached to the transom at both points.

I strongly believe you will regret mounting to your stern rail. It doesn't matter how high or low you raise the dinghy, over time the weight will bend the stern rail and stress the stern rail mounts creating cracks and leaks (at best). Even the dinghy gently swinging and bouncing while underway will stress the stern rail.

Not to mention what happens when navigating through any measurable wind and waves. I can easily imagine getting caught out in an expected storm (it happens) and as you hit the trough of a wave (doesn't have to be a big one) your davits tear off your stern rail and goodbye stern rail, davits, and dinghy.

Kinda unrelated but I recall crewing on a boat years ago hopping down the coast and the skipper tied the dinghy to the stern rail before departure on a beautiful calm day. I tried to gently warn him and offered to tie it to a stern cleat but he was sure it wasn't a problem. 2 hours later the wind/waves kicked up (35 knot winds, 8-12 foot waves) quite unexpectedly and the dinghy dived into a wave and the force pulled it free from the stern rail by pulling it off the mount. Lost the dinghy and severely bent the stern rail, an expensive lesson. The USCG eventually recovered his dinghy and he ended up getting it back though.
__________________
Living our dreams cruising the Pacific Northwest in our 1985 Nauticat 43.
Follow our travels at www.instagram.com/sv__grace
SV__Grace is offline   Reply With Quote
Old 02-06-2022, 08:16   #14
Registered User

Join Date: Jun 2019
Location: Rochester, NY
Boat: Chris Craft 381 Catalina
Posts: 3,687
Re: Installed my new davits, thoughts?

These were designed for the upper mounts to be on the stern rail (and the brackets for that were included). Lowers can go on either the transom or deck. That's why they also included the braces to the swim platform to support the stern rail. Although my stern rail is not the strongest design by any means, hence my concern about what else I can brace.

The situation you're describing with a failure is exactly my concern. Realistically, the most likely failure mode on my rail would be cracking the welds where the stanchions meet the mounting plates on the deck (that whole assembly is 1 piece, no slip in stanchions). So I definitely want to limit flex to avoid a failure there.

As far as waves hitting the dinghy, that's not much of a concern on this boat with the dinghy 5 feet off the water. The wide, flat stern is buoyant enough that if I manage to sink the dinghy into a wave, I'm already in serious danger of losing the boat. The boat is solidly a coastal cruiser, not an ocean crosser.
rslifkin is offline   Reply With Quote
Old 02-06-2022, 08:22   #15
Registered User
 
SV__Grace's Avatar

Join Date: Dec 2019
Location: Currently cruising PNW
Boat: Nauticat 43 ketch
Posts: 703
Images: 5
Re: Installed my new davits, thoughts?

Quote:
Originally Posted by rslifkin View Post
These were designed for the upper mounts to be on the stern rail (and the brackets for that were included). Lowers can go on either the transom or deck. That's why they also included the braces to the swim platform to support the stern rail. Although my stern rail is not the strongest design by any means, hence my concern about what else I can brace.

The situation you're describing with a failure is exactly my concern. Realistically, the most likely failure mode on my rail would be cracking the welds where the stanchions meet the mounting plates on the deck (that whole assembly is 1 piece, no slip in stanchions). So I definitely want to limit flex to avoid a failure there.
As far as waves hitting the dinghy, that's not much of a concern on this boat with the dinghy 5 feet off the water. The wide, flat stern is buoyant enough that if I manage to sink the dinghy into a wave, I'm already in serious danger of losing the boat. The boat is solidly a coastal cruiser, not an ocean crosser.
Don't evaluate your davit mount in optimum conditions while tied to a dock. Boats are in motion when they are used.

The weight of the dinghy in motion, especially up and down when navigating in waves, creates more force on the davits and stern rail, would you agree?

The closer together and higher the waves, the more force. I would always plan and prepare for the worst case scenario and I don't see that you are doing that.

I was not implying the dinghy has to hit waves for this to happen and my story, as I mentioned, was "unrelated," I'm not worried about your dinghy diving into the water while on your davits either.
__________________
Living our dreams cruising the Pacific Northwest in our 1985 Nauticat 43.
Follow our travels at www.instagram.com/sv__grace
SV__Grace is offline   Reply With Quote
Reply

Tags
davits

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Installed New Belt in Yanmar 3jh4e wronco Engines and Propulsion Systems 11 01-08-2014 14:03
For Sale: Never Installed SS Martek Davits montenido Classifieds Archive 1 06-04-2013 10:14
New Mooring Installed But.....? Hoohaa Anchoring & Mooring 9 08-10-2012 02:09
New Speakers Installed ! Ahhh, Stereo . . . Butler Flotsam & Sailing Miscellany 0 23-07-2011 22:20
New purpose built compression beam installed fastcat435 Multihull Sailboats 5 03-03-2008 02:21

Advertise Here


All times are GMT -7. The time now is 20:24.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2022, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2022, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.