Trawler Mast to lift Dinghy?

Hello All
I have a 1974 Marine Trader Dual Cabin 34. I'm evaluating ways to ship and stow my 9.5 ft inflatable keel dinghy and 8hp outboard. Bonus points if I can keep the engine on it, in calm water at least. I'm thinking of trying to use the boom of the mast as a lifting device. Is this nuts? There's a tie point on the center of the flybridge cockpit that seems to serve as fore/aft stabilization - its a substantial tie point with a turnbuckle, can only be to run a cable from the mast to hold it against stern loads.. I'm thinking that the dinghy could be sort of shimmied up onto the swim platform, gunnel to stern, and then secured and the boom used to raise the other gunnel out of the water and stowed maybe at a 15 degree angle, then this position held with lines cleated off to the deck. Thoughts? Are these masts strong enough to even lift the whole thing right out of the water onto the deck?.. Although I don't know where I would put it, maybe up on the flybridge. In rougher water I could pick the outboard off with the boom and stow it on deck, then raise the aft-facing gunnel of the dink up parallel to the stern for a better hold. What does everyone think?

Without looking at the rig or pictures or inspection or any more info....one would be really out on a limb to advise anything.

Many trawler masts/booms can lift dinghies, but each one depending on maintenance and rigging may have completely different capabilities.

psneeld said:

Without looking at the rig or pictures or inspection or any more info....one would be really out on a limb to advise anything.

Many trawler masts/booms can lift dinghies, but each one depending on maintenance and rigging may have completely different capabilities.

Click to expand...

I'll try to get pictures of the pieces tomorrow, I haven't installed it on the boat yet. Based on what I can see, the mounting hardware is pretty sturdy, I just refurbished the mast and boom - filled any cracks with CPES, and coated it with like 15 coats of spar varnish. I may need to upgrade the rigging a bit depending on weight but that's par for the course here I think. Wondering what configurations people have used.

My mast has a bronze foot that uses about a 1" thick pin to mount to the base on the boat, to allow it to pivot down to go under bridges. I'm wondering also when going down rivers with calmer water and a lot of bridges if it could be propped up at about a 30 degree angle or so, so it protruded off the back of the boat a bit, and then secured in a sort of tripod with two tightened cables to either side to hold it in place. Could the dinghy actually be towed by the end of the mast in this configuration to keep the cable up out of the water and give more control? Crazy idea I know but I keep thinking about it..

We had a Livingston dinghy on Weaver Snap Davits, then got a much heavier, larger dinghy. I tried to haul the new one by hand, once. It almost pulled me off the boat.

I modified the snap davits to work with the new dinghy, then attached a long boom to the existing mast. In the photo below, you can see a dark square on the boom close to where it meets the mast. That's a manual winch meant for pulling small boats onto small trailers.

The winch wire goes through a pulley at the end of the boom, which makes hauling the dinghy much, much, much easier! The whole affair was cobbled together just before a summer holiday cruise 4 years ago, and is still there without any more tweaking.

Large stainless steel carabiners with spring loaded gates were the key for attaching the dinghy to the modified snap davits, especially if there is any kind of chop. Crucial finger savers.

Just letting you know there might be a frugal option with a little forethought and planning.

Just remember that filling cracks with CPES and then varnishing does add back the structure lost with the crack. It will look better but if the crack was deep there may be some strength lost. Maybe have a person that does sailboat rigging look at your rigging and they may be able to give some guidance as to what it might lift.

MurrayM said:

We had a Livingston dinghy on Weaver Snap Davits, then got a much heavier, larger dinghy. I tried to haul the new one by hand, once. It almost pulled me off the boat.

I modified the snap davits to work with the new dinghy, then attached a long boom to the existing mast. In the photo below, you can see a dark square on the boom close to where it meets the mast. That's a manual winch meant for pulling small boats onto small trailers.

The winch wire goes through a pulley at the end of the boom, which makes hauling the dinghy much, much, much easier! The whole affair was cobbled together just before a summer holiday cruise 4 years ago, and is still there without any more tweaking.

Large stainless steel carabiners with spring loaded gates were the key for attaching the dinghy to the modified snap davits, especially if there is any kind of chop. Crucial finger savers.

Just letting you know there might be a frugal option with a little forethought and planning.

Click to expand...

Yes! Thanks The snap davits are a great idea I'll probably pick up a pair. Do you stow your dinghy upright on the swim platform or more parallel to the water? Do you leave the motor on?

brianaderer said:

Yes! Thanks The snap davits are a great idea I'll probably pick up a pair. Do you stow your dinghy upright on the swim platform or more parallel to the water? Do you leave the motor on?

Click to expand...

Dinghy lays on its side, on the swim step, bottom facing aft.

Our snap davits were made for a Livingston dinghy, so we had to modify things for the new dinghy which is shaped like an inflatable but made of plastic.

Motor comes off, but there are solutions out there.

MurrayM said:

Dinghy lays on its side, on the swim step, bottom facing aft.

Our snap davits were made for a Livingston dinghy, so we had to modify things for the new dinghy which is shaped like an inflatable but made of plastic.

Motor comes off, but there are solutions out there.

Click to expand...

I'm looking at the weaver site right now.. pretty slick!

I think a lot of trawler owners visualize using their mast and boom to lift dinghies, or motorcycles or whatever. I really evaluated mine from all angles. The boom doesn't extend beyond the back of the boat so that really wouldn't work. I does reach over the side but really not by an awful lot, then how do I bring the dinghy closer in to mount on the aft cabin?

I'm sure the structure was able to support almost anything I wanted to hang on it but it just didn't seem practical.

In the end I got rid of the boom, cut ten feet off the mast and went with Weavers.

pete

Any who have heard my story before, stop reading now.

My boat came with the usual "trawler mast and boom".
I had a Sabot. It was built to win races, which it did. That meant weighing in close to the rule minimum of 52 lb fully rigged. So without the mast, boom, sail, rudder, centreboard, etc, it weighed a lot less than 52 lb. When I lifted it with my "trawler mast and boom", the base fitting for the mast broke and the whole thing came crashing down. Useless, useless, useless!!!
I had a new base made of SS channel, strong enough to do the job.
Several things changed, mandating a longer boom, a taller mast, and enough lifting capacity to hoist a Laser to a rack I had built so the Laser would sit above the back hatch, high enough that I can walk upright below it.
Another consideration was the stays that the original mast came with, that threatened you with decapitation whenever you had to transit the steps down from the flybridge. Those had to go.
The solution was a piece of aluminum irrigation pipe, tall enough to go up from the lower deck, (the original was mounted on the upper deck), pinned at the edge of the upper deck, no stays. When lifting the Laser I ran a temporary forestay forward to an attachment point at the base of the helm chair, otherwise no stays. It worked well for the years we carried the Laser.
The mast now also carries the radar dome. when lowered to go into my shelter, the whole affair rests on a two legged prop, on the back deck. The mast head is above the dinghy. The boom is high enough that I can stoop and go under it.

Your story will be different, but this might give you some data points to consider.

We installed snap davits (Ceredi brand from Italy, the "new" dinghy had Ceredi pads fitted). Convenient, quick and easy, but I rather not have the dinghy on the swimstep. See if you can make the mast and cabintop storage work but if not, snaps are good. Don`t forget the hold off rods to nicely hold it in place.

We store our 10 ft RIB with 8 hp outboard up top. The boom has two trailer winches, one to raise and lower the boom and the other to winch the load up and down. The bipod mast is supported with a set of shrouds and a pair of short forestays. We, too, have an anchor point forward on the flybridge that is clearly intended for a forestay. As the dink represents quite a load we left this off and added a longer forestay that runs forward to the foredeck, and two lower outboard shrouds that take the tension load from the outboard edges of the housetop down to the bulwarks.

It will all depend upon the construction of your cabin roof, the mast and boom, and how the mast is stayed, but we find it very handy to stow the tender on top.

Factory wood mast and boom here on my 1979 49 MT RPH. Lifts my WM 10-ft RHIB just fine, with a 15hp Johnson on the back. I installed ATV electric winches and run straight lines (no block and tackle for reduction). Easy up and easy down. 4 heavy stays connected to the decks. Detailed pics if needed.

I am no rigging expert, but have used a lot of similar equipment in salvage and other commercial maritime work.


My mast and boom easily handle my 150lb dingy set up. When in doubt, do your own weight handing test (plenty of internet suggestions) to ensure some semblance of safety.


Even with some rot along the mast glue lines my mast easily handled things ....pretty sure rigging is designed to mostly put mast and boom in compression so I was confident in the amount of wood left. I filled the rot area with reinforced epoxy resin (probably as or stronger than before).



Lifting objects onto the after deck or rear stateroom cabin simply involves raising the boom to bring the lifting point in closer. Yes a bit complicated with just 2 hands and no remote controlled winches, but doable if you want to.


A boom that can't lift straight up out of the water isn't a show stopper... as long as the angle from the lifting point outward isn't excessive, holding the lifted object away from the hull and rail till the dingy clears is possible. On my boat it is easier to lift from the boat sides versus over the transom but I don't bother especially if in a slip where pilings interfere. But I still usually just lift over the transom, fending the dingy off obstructions as it comes aboard. The swim platform may be the biggest obstacle but I have the folding arm dingy davits that bolt to the swim platform so that bump is easily overcome.


Even when I had Weaver davits I used the mast and boom with an electric winch to lift and somewhat hold the aft dingy gunnel to the raised position...easy peezy.


I cannot say all trawler mast setups work like mine or are safe....a good inspection of pieces and parts is necessary than some head scratching what you can safely can do with it. If not confident in your backyard rigger skills....call in someone who you trust (or a pro if necessary).

My mast didn't do it for me. This is how I chose to do it since the davits were on the boat when I bought it.

My mast, boom and stay setup is quite beefy and lifts my fully rigged dinghy onto the aft deck with no problem. (From the side only) I estimate the total weight of the rigged dinghy at about 350lbs. I consider that about as much weight as I’m comfortable lifting. This year I have replaced all the rigging with new as I found two swages that were cracking. That said, I wouldn’t push it and we never put anybody in or under the lifted dinghy.

Ken

Hi Brian, I can’t offer you any advice on your question. My boat has davitts for her 11’ Boston Whaler dinghy. But I do have another related question which I hope you can help me out with. I also have a 1974 MT...a 35’ triple cabin. A former owner replaced the original pilot house with an aluminum one made of 3/16” aluminum plate. He did an incredible job and even welded a base mount for the mast on the deck of the aft cabin...but he didn’t reinstall the mast and it did not come with the boat. I want purchase one or have one made but do not have any dimensions for it and the boom. Could you give me the dimensions of your mast and boom? It would be great if you could email me a picture of it as well. Another comment to your post suggested that information would need to be known to anyone who could advise you on your request so this may help both of us. Thank you. Roland

Brian, we used our mast and boom to raise the dingy on our last trawler. While it was possible to be honest that mast wasn't setup to lift a dingy so it was a giant pain in the backside. Hard work, hard to control and often felt unsafe. We ended up using weaver davits on the swim step which made deploying/retrieving much easier and safer.

On our current trawler the mast and boom was designed and fitted by the factory to lift the dingy (it's stored forward of the PH). It works well and we can deploy/retreive in about 15 minutes.

If you go down this path consider changing the geometry of the mast, adding any required standing rigging, blocks and electric winches, etc to make it simple and safe. Plenty of trawlers do this well but the rig needs to be setup properly.

Dinghy location

We went thru a couple of attempts to deal with a dinghy and its use.

I can categorically state, the more difficult it is to launch, the less you will use it. A mast & boom affair might seem easy, but with tie-downs and rigging, knowing people who kept a dinghy on a roof with a crane, they didn't use the dinghy very often.

I can also state, having the engine on the dinghy will be stronger insurance you will use the dinghy.

We started with something called a sling davit. It is a cargo net connection that attaches to the boat's swim platform and has a tie-up to handrails. See here; (davits, davit systems for inflatable boats). The main drawback was that you had to remove and replace the OB to use. I always expected ours would go for a swim test.

We finally found davits that would attach to the swim platform. You could attach davits to the stern (we, being a sundeck, with our berth on the other side, couldn't do that). See here for what we got; (https://www.atkinshoyle.com/products/davits.html). Highly recommend this company due to their support & quality. Better quality than other offerings as well.

There is also the advantage of paying for your davits in Canadian money. That could provide a discount on the currency exchange.

The davits allow for the OB to stay attached and it is easy to launch & retrieve the dinghy. Tying it properly it will ride through some rough water.

Any questions, drop me a reply.

dinghy lift

brianaderer said:

Hello All
I have a 1974 Marine Trader Dual Cabin 34. I'm evaluating ways to ship and stow my 9.5 ft inflatable keel dinghy and 8hp outboard. Bonus points if I can keep the engine on it, in calm water at least. I'm thinking of trying to use the boom of the mast as a lifting device. Is this nuts? There's a tie point on the center of the flybridge cockpit that seems to serve as fore/aft stabilization - its a substantial tie point with a turnbuckle, can only be to run a cable from the mast to hold it against stern loads.. I'm thinking that the dinghy could be sort of shimmied up onto the swim platform, gunnel to stern, and then secured and the boom used to raise the other gunnel out of the water and stowed maybe at a 15 degree angle, then this position held with lines cleated off to the deck. Thoughts? Are these masts strong enough to even lift the whole thing right out of the water onto the deck?.. Although I don't know where I would put it, maybe up on the flybridge. In rougher water I could pick the outboard off with the boom and stow it on deck, then raise the aft-facing gunnel of the dink up parallel to the stern for a better hold. What does everyone think?

Click to expand...

My GB 36 classic has a dinghy cradle on top of the aft cabin. I lift my 80 lb dinghy with the boom with no problem. I also have a stainless steel hook and loop system on the swim platform and stern of the dinghy so that I can mount it there. I do not keep the motor on the dinghy in either case, although I could and still use the boom to lift it off the cabin top. Honestly, if you want to keep the motor on your dinghy and lift/lower it with ease, buy davits and mount them to your aft deck or the transom.

You mention that you have a connection point for a stay leading forward from the mast, but you don't mention anything about side to side supports ( shrouds ). Even if you only plan to lift over the stern, a little wave action and a swinging load could create significant sideways stress on the mast.

Great looking Sundowner I have the same one. Ours has the full mast and two sails.

see
https://www.facebook.com/100028177805917/videos/803243527291567/

We also have a GB 36 as described in Reply #20. It came with Weaver clips which mated to the ss clips glued on the gunwale of the 9.5 ft. RIB. To use, the dinghy had to be emptied of everything including the motor, then the dinghy clipped on the swim platform and tilted up on it's side. PIA, unnatractive and prevented the use of the swim platform. Hated it, and got rid of it right away.

We then switched to installing a rack on the roof of the aft cabin, and used the mast & boom to hoist the dinghy into or out of the water. This was much more seaman-like and secure. We used a 4 part tackle from the tip boom to the dinghy, and the tackle that was already holding the boom to the peak of the mast to raise the boom, bringing the dinghy closer to center it on the rack. The o.b. remained on the dinghy transom, and overhung the aft cabin roof by just enough to be clear. The problem was it took both my wife and I together about 20-30 minutes to deploy or retrieve the dinghy, so we didn't use it much.

Round 3. Forget about your mast and boom, and look into Rothskelly/Olsson Transom Davits. We rigged the lightest one (250# rated) on our transom and either of us alone can launch or retrieve in just a minute or two. Really. I use a simple 4-part tackle to raise the davit once the dinghy is attached to it. The contents of the dinghy stay in place, including the outboard. Simple, ship-shape and not expensive. Brilliant. Third time was the charm. Do yourself a huge favor and check it out. I have no skin in this company.

Mast and boom options

Hi all, im looking to install a mast and boom. The previous owner removed the mast for some reason and i’m keen to reinstate it. I’m thinking that i could use it to lift a small tender onto the deck or the roof. I’d also like something to fix the antennas and possibly a radar dome onto. Is a timber mast practical for this or would finding an aluminium yacht mast and cutting it down be an option? Not sure where to start. The base of the mast seems to be solid and in ok shape. Any guidance will be appreciated.

Sounds a good idea. Tried the PO for the one he removed? You could ask why he removed it.

Couple of things to consider. Is the roof structure strong enough? There’s a substantial load at the mast step, usually there’s a compression post or other means of handling the down force.
Looking at the remains, there may have been a mast that could pivot down for bridge clearance or other height issues. I would consider using an aluminum piece, with isolation bushings from the stainless base you have. There must be some places on the roof where stays were attached. Maybe you can re use.
A wooden mast can work, there are thousands in use now. I prefer metal. Wood will rot eventually.
I replaced the old wooden mast on my boat with a cut down sailboat mast. Very happy with the result.

During the refit of Weebles, I removed the mast/boom to make way for a hard top and to lower air draft in anticipation of life on the bridge-speckled ICW where Weebles will live (coincidentally, about 1/4 mile from the Corey Ave Bridge in St Pete Beach FL). I replaced it with a Nick Jackson pipe davit.

The new pipe davit is fairly manageable. The old mast/boom was not. Because the pipe davit is located at the outer edge of the boat, the swing-arm is only about 5-feet. The mast was obviously on the centerline and needed to be about 12-feet to get the dink clear of the gunwale. This increased distance made the boom pretty unweildy in anything other than flat waters. I can tell you my recent experience is anchorages seem to have some swell or chop - La Paz especially would have been bordeline dangerous with my old mast/boom arrangement. Was mildly difficult with pipe davit.

I know it looks simple on paper. But like so many things on a boat, practical application pierces the simple solution sometimes.

Good luck with whatever you decide

Peter

Peter makes a very good point. The centerline mounted boom is quite difficult to manage, especially by yourself. I will be making an adjustable rope clutch for mine to limit the speed and scope of swing. My boom is really heavy, all stainless with a slide out inner section. I think I can get about 18 feet extension all total. Why? I have no idea what they were thinking when it was constructed.
Maybe a short mast for lights/antennas and a separate dinghy crane would be a good choice. A crane with powered swing would really be nice.

FWIW, my solution to storing and launching a 13', 800 lb Boston Whaler on the foredeck was a telescoping boom that runs out 4', a topping lift in line with the angle of lift, and winches on the mast for boom extension, hoist and raising and lowering the boom. The principal forces you need to deal with are at the gooseneck (compression) and the masthead (tension). The attachment of the mast to the deck is pretty much irrelevant.