DIY davit or lift? - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance
 Not a Member? 
  #1  
Old 07-22-2009
Member
 
Join Date: Jun 2009
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
corny is on a distinguished road
DIY davit or lift?

I know there's some very nice davits available in the $500 to $1500 range. I could just buy one...but I enjoy the satisfaction of making things and saving some money in the process.

Has anyone ever built their own davit or lifting device (using a block and tackle sort of arrangement) to raise/lower things in and out of a dinghy? My need is fairly simple...raise and lower about 75 lbs. safely and with relative ease.
Reply With Quote Share with Facebook
  #2  
Old 07-22-2009
Member
 
Join Date: Jun 2009
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
corny is on a distinguished road
I'm kind of cooking up something in my head using Schedule 120 PVC pipe, some nice sanded and varnished plywood gussets, possibly slipping over a lifeline stanchion with a guy wire running thru the top of the stanchion and attaching at two angling points behind the stanchion for support, having the pipe pivot on the stanchion (with lifelines removed for use) and probably a stainless plate mounted below the stanchion on the underside of the gunwhale for additional support.

The whole thing would assemble with stainless bolts, washers and wing nuts so it could easily be broken down and stowed, yet simply assembled in a few minutes.
Reply With Quote Share with Facebook
  #3  
Old 07-22-2009
Senior Member
 
Join Date: Nov 2008
Location: Long Island
Posts: 2,129
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 6
WanderingStar is on a distinguished road
I'm thinking of simple straight oak peices with blocks. Mounted to the mizzen gallows with jaws or lashing at the base. Supported by a line at the top. Angled 45 degrees. One line, run through blocks on the fwd and aft thwarts of the dinghy. About 2-1 advantage (less friction). Haul away til she's at the rail. Maybe incorporate the support lines too, so it comes inboard at the end.
Reply With Quote Share with Facebook
  #4  
Old 07-23-2009
Member
 
Join Date: Jun 2009
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
corny is on a distinguished road
Well, first attempt with PVC was a failure, but not ruling out PVC as the construction material...yet.

The problem was trying to build all of it with PVC joints, bends, etc. Since the pipe only fits into fittings 3/4", the cement and bond is not strong enough to handle the stresses. Next attempt will be with solid pieces, drilled and bolted together with stainless hardware.
Reply With Quote Share with Facebook
  #5  
Old 07-23-2009
Bene505's Avatar
Glad I found Sailnet
 
Join Date: Jul 2008
Posts: 3,550
Thanks: 5
Thanked 37 Times in 36 Posts
Rep Power: 7
Bene505 will become famous soon enough Bene505 will become famous soon enough
Quote:
Originally Posted by corny View Post
Well, first attempt with PVC was a failure, but not ruling out PVC as the construction material...yet.

The problem was trying to build all of it with PVC joints, bends, etc. Since the pipe only fits into fittings 3/4", the cement and bond is not strong enough to handle the stresses. Next attempt will be with solid pieces, drilled and bolted together with stainless hardware.
PVC snaps cracks and fails, expecially at the joints, which are not made to be load bearing at all. I build a $1000 frame for a tarp last winter. The wind destroyed it. The 2" pipes' fittings snapped. I ended up messing up my gel coat big time in one place and also over an extended area to a lesser degree. That experiment is over. Suggest you stay away from PVC as a construction material. There's a reason no one else in the world uses it for anything load bearing!

EDIT: I like the oak idea. Pine is not a very strong material.

Go with something that was made to take a load. Stainless steel pipe is used for radar posts, for instance. In retrospect, I wish I had used 2x4s. At least I'd have something that I could re-use next winter. For what you are talking about 4x4s might work. You could take them and carve them into something rounder or engraved/beautiful if you know anyone who can sculpt, and you could stain them any color you like.
__________________
Posts you might like:

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
. .

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
. .
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
. .
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
. .
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
. .
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #6  
Old 07-23-2009
Member
 
Join Date: Jun 2009
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
corny is on a distinguished road
Yeah, I'm more and more thinking *not* on PVC.

We have a 28 Ranger, so it's not like we have the room for anything permanently mounted, unless it was a commercial offering in stainless. Ideally, it should come apart or fold up for easy stowage and be as light as possible (which is why I looked away from wood).

Here's a question, how much weight would the boom be able to safely handle? I could just hook the block and tackle up to the end of the boom and swing it over the side of the gunwhale. The heaviest thing we'll be raising and lowering is a deep cycle battery for an electric motor.
Reply With Quote Share with Facebook
  #7  
Old 07-23-2009
Senior Member
 
Join Date: Feb 2009
Location: Michigan
Posts: 211
Thanks: 4
Thanked 9 Times in 9 Posts
Rep Power: 6
ctl411 is on a distinguished road
I think Good Old Boat had a article on homemade wooden davits they looked nice.
Reply With Quote Share with Facebook
  #8  
Old 07-23-2009
Member
 
Join Date: Sep 2008
Location: Portland, OR
Posts: 35
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
TractorJohn is on a distinguished road
Thumbs up support boom with halyard

Quote:
Originally Posted by corny View Post
Yeah, I'm more and more thinking *not* on PVC.

We have a 28 Ranger, so it's not like we have the room for anything permanently mounted, unless it was a commercial offering in stainless. Ideally, it should come apart or fold up for easy stowage and be as light as possible (which is why I looked away from wood).

Here's a question, how much weight would the boom be able to safely handle? I could just hook the block and tackle up to the end of the boom and swing it over the side of the gunwhale. The heaviest thing we'll be raising and lowering is a deep cycle battery for an electric motor.
If the boom lift is connected near where you connect your load (block and tackle) you should be able to handle a lot but as you swing over the side the force directions change and your boom to mast conection is stressed. Also the lifting halyard may not like being pulled sideways, that being said we used to swing our boom over the side and hang a rope swing for swimming with no problems. I would think a battery lift is no problem either.
TJ
Reply With Quote Share with Facebook
  #9  
Old 07-23-2009
imagine2frolic's Avatar
Senior Member
 
Join Date: Aug 2008
Posts: 1,831
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 6
imagine2frolic is on a distinguished road
We have a guy in the marina building with 1"SS tubing, and using a conduit tubing bender. Except for some small scratches it's working out for him.......i2f
__________________
20 MPH ain't fast unless, you do it in a 1000sq 3/2 house on 10foot waves
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


BORROWED, No single one of us is as smart as all of us!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #10  
Old 07-24-2009
CaptainForce's Avatar
Senior Member
 
Join Date: Jan 2006
Location: living aboard since 1972
Posts: 1,697
Thanks: 0
Thanked 12 Times in 12 Posts
Rep Power: 9
CaptainForce will become famous soon enough
My DIY dinghy davits are SS pipe with added shrouds from their ends to the top of the mizzen.

This photo shows a bording ladder laying on top of the davits so it's difficult to distinguish the davit pipes, A solar panel is fitted above. 'take care and joy, Aythya crew
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Topping Lift and Sail Shape NCC320 General Discussion (sailing related) 13 02-24-2011 10:25 AM
Davit Problem; Expert Needed danielgoldberg Gear & Maintenance 18 11-24-2008 01:01 PM
Solar Panel Mounting On A Davit Freesail99 Gear & Maintenance 8 08-14-2007 02:22 PM
Boat lift in a storm knothead General Discussion (sailing related) 5 08-27-2006 10:24 PM
Keel Lift NJW3 Seamanship & Navigation 6 09-22-2003 06:59 PM


All times are GMT -4. The time now is 10:32 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.