Boat that doubles as a truck cap

[member 63885]

HI All

The Idea is to build a lightweight boat that doubles as a truck cap. I know that this would involve a lot of compromises, but it also solves the problem of transporting the boat. I currently have an 8' zodiac, and it is a pain setting it up and taking it apart.

The boat will be used for fishing on small lakes and rivers. We have fished from Florida to Ontario, usually while on vacation

For power I have an old Briggs and Stratton electric outboard that is supposed to be equivelent to a 3 hp motor. I have a homemade battery pack to power it that is made from 252 laptop batteries. The motor weights about 75 lbs, the battery about 25 lbs, im about 225 lbs and my son is maybe 100 lbs

The boat would be about 6 feet wide by 8 feet long by 2 feet deep. I made a scale foam model to get an idea of what it would look like.

I have never built a boat before but I have wood working skills and a large basement to build it in with a table saw, band saw, etc. I thought I would build it with a plywood frame then cover some of the straight parts like the bottom with plywood, and some of the rounded parts would be covered with Dacron, like Geodesic Airolite Boats does. I was going to build a canoe but didnt follow through so I still have the Dacron laying around. Frankly much of the boat will be built out of plywood I have in the shop, as much as practicle.

The reason the boat has a catamaran look to it is the distance from the bed of the truck to the roof of the cab is 24", but my motor is 21" to the top of the ventiation plate.

So the first question would be, is it worth making a catamaran style hull to fit the motor, or should I just make the bottom flat and cut the transom 3" lower? Maybe it doesnt matter either way as it will have such a small motor?

Just to be clear about the battery, I am not using the 12v lead acid in the picture. The battery is to the right of the 12v battery. I was using the lead acid battery to power the spot welder to weld the laptop batteries together.

 

[TANSL]

I just make the bottom flat and cut the transom 3" lower?

This, if possible, seems more sensible and much cheaper.

 

[fallguy]

Build it in foam sandwich. Otherwise it'll get too heavy to take off the truck without risking damage to your back. I'm not sure that the cat style wouldn't be an improvement. It looks a lot like a 13' Whaler Sport hull. The cat hulls would be easier at the beach edge as well.

 

[fallguy]

What is the aversion to trailering? Or is it because you want to drop into lakes without a trailer? The trailer would just simplify things, even if you don't use it to launch. I pulled a boat off the back of my truck one day after driving 300 miles to do some fishing. I tweaked my back so bad I couldn't even take it out.

As for making a foam sandwich ultralite truck cap; it is still a neat idea. The benefit of the truck cap being homemade and foam is it'd have some insulating value and you could sleep it.

The camper/boat idea is ingenious, but not very practical. After a day of fishing, putting the boat back up on top and then sleeping in a drippy wet campertop is not my idea of fun. No disrespect, the idea is pretty neat, just not the way I'd go.

 

[bjdbowman]

I like the idea... go for it!

First, I would incorporate some way of rolling the boat off the back of the truck and down some ramps (tracks to keep the boat from falling off the side). I would not want to have to lift the boat onto the truck ever. Levers, ramps, pulleys and screws are all ancient tools, why not use them?

Second, I would make the boat longer than the bed... I have a full size bed (8') and I would make the boat longer to overhang the lowered tailgate and and a bit more, and then create a folding device (to enclose the area for security) so that you could use this area to enter into the bed from a space created under the boat and behind the lowered tailgate. This would give you more interior area, a better boat, and easy access to using the camper area.

As for the camper... you will need ventilation. You could build a moving rack/jack system that would lift the boat a few feet higher off the bed rails for use when camping. You could fill the void under the boat and over the bed rails with a snap in canvas/screen and then you could have a working camper with windows and air.

You could install lights and signage on the hull upside down for when the boat is upside down acting as a cargo cover on your bed... like the middle brake light etc.

Just some of my ideas.... But I think that this would make a great project and something that others would want to replicate as well.

 

[Rurudyne]

Have you considered a folding boat?

I'm thinking more of a catamaran folding in an M with the amas the sides of the M because it would have more surface area. Accommodations could then be tent-like and used only when wanted.

To get a longer boat imagine if the amas also were hinged beyond the bridge deck to fold inward fore and aft.

Two or more sets of fold down legs with wheels would facilitate loading on and off.

Unloading it would kinda go like this: fold down rearward support legs, pull out till the foreword ones can be lowered, while that end of the boat is still supported by the truck. Once clear of the truck it could be unfolded to full width. Then the tuck away extensions unfolded and locked into place.

If light enough to be picked up by a couple of men or if height adjustable the fold down supports could be attached to the truck and you could do away with the second set of fold down legs. In that case it might be like a folding boat on a fold away trailer.

 

[portacruise]

Concept has been around for awhile in different configurations. Seems like I've seen the truck cap version many years ago.

Dedicated railers are not worth the hassle for small boats that can be handled by one man- IMHO (registration cost, bearing seals and grease, tire pressure checks, storage/parking, backing up, electrical connector corrosion, etc.).

Here's one:

Here's another as a trailer:

PC

 

[Doug Lord]

Mike Gentzhorn started a company a few* years ago building exactly what you are talking about. May or may not be in production but he did get a patent on it.
* 30! (-my how time flys-he built a model on my front porch!)
US4923242A - Vehicle cap and boat combination - Google Patents https://patents.google.com/patent/US4923242

 

[member 63885]

What is the aversion to trailering? Or is it because you want to drop into lakes without a trailer? The trailer would just simplify things, even if you don't use it to launch. I pulled a boat off the back of my truck one day after driving 300 miles to do some fishing. I tweaked my back so bad I couldn't even take it out.

As for making a foam sandwich ultralite truck cap; it is still a neat idea. The benefit of the truck cap being homemade and foam is it'd have some insulating value and you could sleep it.

The camper/boat idea is ingenious, but not very practical. After a day of fishing, putting the boat back up on top and then sleeping in a drippy wet campertop is not my idea of fun. No disrespect, the idea is pretty neat, just not the way I'd go.

I don't like the idea of trailering a boat because we live in Ontario and go to Florida in December, then Georgia or South Carlina for the March break. Its a long drive and it is a bit of a hassle towing that far. I like to be able to keep up with traffic, go through drive throughs, that kind of stuff. I also dont really have a place to keep a boat and trailer. This boat/cap I could keep in the backyard. I also have a toyhauler and it will fit in the back. Sometimes we take the RV south, sometimes rent a place. No sleeping in the back of a trailer for me, Im past that point in my life! I need comfort

 

[member 63885]

Concept has been around for awhile in different configurations. Seems like I've seen the truck cap version many years ago.

Dedicated railers are not worth the hassle for small boats that can be handled by one man- IMHO (registration cost, bearing seals and grease, tire pressure checks, storage/parking, backing up, electrical connector corrosion, etc.).

Here's one:

PC

Yes I saw this video, it may be where I got the idea.

I think it can obviously be done better with a pupose built boat/cap. The truck in the video looks like a short box, 6 1/2' long by 6' wide. I have a long box, 8 1/2' by 6 1/2' so that should be more boatlike. Also light weight is important as it needs to be easily removed. What im thinking is wood frame, thin plywood floor, 1" foam board then cover with fabric saturated in glue, then painted. (poor mans fiberglass) I know this is frowned on because it does not make a durable boat, but I know that it will only get used a few times a year, for a few hours at a time. I like building things. The end point is not the goal, it is the journey I am looking for.

 

[JSL]

I saw one years ago. If memory is correct, the fellow used a Livingston Dinghy (or something similar) and it sat transom for'd (bow at the tailgate) on the box. He had some rollers/brackets each side of the transom so the boat would roll off the box and/or he could lift it up at the bow to load the box. The smart move was most 'parts' were 'off the shelf' so he did not have to 'invent' anything.

ps: Gonzo's 'jon boat' makes sense & worth a look

 

[gonzo]

A light weight jon boat would do the trick. I have a 10 footer that can be lifted with one hand. This is an example:
2018 L1032 Riveted Fishing and Hunting Boats | Lowe Boats https://www.loweboats.com/jon-boats/l1032-jon/#specifications
2012 Lund 1032 Lund Jon - Full technical specifications, price, engine - The Boat Guide https://www.guideautoweb.com/boat/specifications/lund/jon_boat/1032_lund_jon/2012/

 

[member 63885]

So I started the "Truck Cap Boat" as I am calling it. I started with a 2x4 frame that is the same size as the truck bed. I leveled it and squared it up. The frame is not part of the boat. It is just to give me a level and square surface to build on

 

[member 63885]

I then built what I guess would be the gunwales out of two layers of 3/4" exterior plywood. They are 3" wide. The ribs are also cut from 3/4" exterior plywood and are 3" wide as well.

A few things to keep in mind. My goals are to keep it simple, I am trying to use off the shelf materials. I am also trying to do in cheaply. The boat will not spend more than a few hours in the water at a time. It will be launched and removed the same day.

I plan on sealing the wood with a poly urathane thinned with varsol.

 

[member 63885]

I mortised the gunwales and set the ribs in. The ribs are notched for three stringers across the bottom as well as at the bottom corner. I dont know if those pieces are called stringers as well? They are 1"x1" pine. They are suprisingly hard to bend. I thought I would glue then in place to the back ribs where there is no bend, then steam them in place and bend them one by one. I then realized I need to steam each one for about an hour to get it to bend! I got the center one bent and glued in place. I managed to break the one to the left trying to bend it without steaming it

Its going to be powered by a 3 HP Briggs and Stratton electric outboard. The transom is one 1/2" piece of plywood that is reinforced by some 3/4" plywood.