Davit Installation

bpatters69

Cadet
Joined
Jan 7, 2012
Messages
11
Hello All,

I live on the Florida Intracoastal and I would like to install a Daivt on my seawall. I purchased the Davit which is rated for up to 1000 pounds. The boat that I will be hoisting is a 10' Avon which weighs about 250 pounds with the motor. The Davit is a manually cranked Davit and the base is flat with 4 holes for fasteners.

In my first attempt at installing the Davit, I drilled 4 holes into the seawall and dropped in 4 x 1/2" redhead fasteners. Two of the redheads tightened down nicely but the front two would not tighten down at all. After a bit more research, I found that redheads are not the right fastener to be using so I took a 5/8 bit and re-drilled each hole for a concrete lag shield so I could drop in a galvinized lag bolt. The galvinized bolts worked better but when I applied downward pressure, the bolts started to slip and the Davit tilted. Ugh. :banghead:

So back to the drawing board. I realize that when I removed the redheads and re-drilled the holes that the holes were probably too big for the lag shields which would not allow the sleeve to tighten down properly. I could just drill 4 new holes, drop in the sleeves and try to install the Davit again but I do not want to drill more holes in my seawall than are necessary. So my question is, am I on the right track? Should I be using a different type of fastener? The lag bolts were 6" long as more info and the sleeves were abobut 2'. Here is a link to the lag shield:

http://www.homedepot.com/h_d1/N-5yc...53&langId=-1&keyword=lag+shield&storeId=10051

My other thought is that the seawall is old and maybe the concrete is too brittle for attaching a Davit? The seawall is probably 30 years old or more.

Any comments and advice is greatly appreciated.
 

rbh

Fleet Admiral
Joined
Mar 21, 2009
Messages
7,939
Re: Davit Installation

Never had much luck with those expanding bolts for verticle hold.

What seemed to work the best was digging oversized hole, setting the bolt in place and pouring concrete or expanding grout to hold the bolt.
 

Georgesalmon

Lieutenant Commander
Joined
Apr 14, 2012
Messages
1,793
Re: Davit Installation

I'm using concrete wedge anchors for my 9000lb car lift. They are a stud that you drive into the hole and then put a nut on and torque it to specs for the size. Mine are 3/4" and there are 5 on each side, torque was nearly all my 1/2" torque wrench (and me sittin on the floor pulling with both hands with feet against the post)could do. Don't know how this equates to a boat davit.
 

Vankaye

Seaman Apprentice
Joined
May 7, 2010
Messages
39
Re: Davit Installation

I live on a lake in Florida and everybody I see with Davits makes a poured "deadman" with large threaded rod embedded
in the concrete to hold the davit.

I think hanging a boat directly from your seawall is asking for a long-term problem. You need to dig and pour. Sinking a piling may be another option.

Just google images of seawall Davits. You'll see the big blocks I'm talking about...

http://www.google.com/imgres?hl=en&biw=1409&bih=770&tbm=isch&tbnid=LfVpft5H5VV-mM:&imgrefurl=http://www.neptuneatlanticboatlifts.com/&docid=Y95TDGN5qlD4-M&imgurl=http://www.neptuneatlanticboatlifts.com/images/img_home_02.jpg&w=230&h=170&ei=h5V1UJ34NqW80AGA6YCoDA&zoom=1&iact=rc&dur=684&sig=106422352266298086659&page=1&tbnh=129&tbnw=179&start=0&ndsp=25&ved=1t:429,r:5,s:0,i:85&tx=75&ty=68
 

cobalt1999

Petty Officer 2nd Class
Joined
Apr 28, 2010
Messages
104
Re: Davit Installation

Talk to Hilti fasteners and ask about using their epoxy to set the fasteners in the concrete. Home Depot carries the epoxy.
 

Ned L

Commander
Joined
Sep 17, 2008
Messages
2,268
Re: Davit Installation

As the others have been saying. Properly set appropriate threaded studs in the concrete first.
 

bpatters69

Cadet
Joined
Jan 7, 2012
Messages
11
Re: Davit Installation

Thank you all for the responses. I ended up buying some Quickcrete epoxy and setting the threaded rods with the epoxy.
 
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