Need help building rooftop hammock stand on Prinsu Rack

[Dissent]

I have a Prinsu Desings rack that I've setup with a folding plywood platform to hold my REI tent for the past few years. I also have a Hennessey Deep Jungle hammock. The hammock is useless above the treeline and I want to remove my plywood setup and rig up an 80/20 enhanced 10-series version of this nifty (read expensive @ $800) product here TrailNest Roof Top Hammock Stands.

I want the arms to hinge and fold down flat to retain the low profile height to fit in the garage. I'm not sure how to rig the arms to minimize side to side play and unsure about the strength to hold me at 250 lbs. I have access to an excellent aluminum fabricator who could make the boxed brackets in the style of the original if needed although I'd like to leverage all bolt together 80/20 parts.

Any engineers out there that can assist with recommendations to accomplish this?

 

[mudgudgeon]

Wow! That's just whacky!
Wouldn't want to stumble getting out in the middle of the night!

Interested to see how you go with this though.

How long is your hammock? Mine is 11', needs about 12' between hanging points, and a good 5' in height to keep my ample ass of the ground

I'd be worried about stability at your weight. I'm 270lbs, and am regularly surprised at the load a hammock puts on things

 

[Dissent]

That's what everyone said when I built my tent platform but that never stopped me. Mine is 10 or 11 feet, have to dig it out and measure it. Planning for 12 feet between hanging points. Stability is the primary concern. TrailNest uses boxed brackets to maximize side stability. I figure short 80/20 'scabs' at the hinge points might work. I reckon 80/20 extruded is as strong as boxed aluminum but I'm no engineer.

 

[JeepinPete]

Hammock camper here! Check out the hammock campers forum, lots of stand ideas there. Here is one that I think would work really well for your situation:

Tensahedron Stand

 

[gungriffin]

I have a Prinsu Desings rack that I've setup with a folding plywood platform to hold my REI tent for the past few years. I also have a Hennessey Deep Jungle hammock. The hammock is useless above the treeline and I want to remove my plywood setup and rig up an 80/20 enhanced 10-series version of this nifty (read expensive @ $800) product here TrailNest Roof Top Hammock Stands.

I want the arms to hinge and fold down flat to retain the low profile height to fit in the garage. I'm not sure how to rig the arms to minimize side to side play and unsure about the strength to hold me at 250 lbs. I have access to an excellent aluminum fabricator who could make the boxed brackets in the style of the original if needed although I'd like to leverage all bolt together 80/20 parts.

Any engineers out there that can assist with recommendations to accomplish this?

What about building something like the Hammock King? You could mount it using 2 80/20 crossmembers on the Prinsu rack right? Use some sort of flexible or expandable steel pole that could mount into a bracket. The bracket would mount onto the 80/20 crossmembers. The bracket could be permanently affixed to the 80/20 on the roof. Then have the poles slide into a drilled hole in the bracket with the drilled hole being used to set the angle of the poles? The nice part about the 80/20 is being able to use the slot to mount the brackets. I am trying to think about how I could do this with my Gobi Stealth rack.

Hammock camper here! Check out hammock campers forum, lots of stand ideas there. Here is one that I think would work really well for your situation:

Tensahedron Stand

That is just simply a great solution. Wow I love seeing solutions like this.

 

[clx16]

Not a very good rendering nor well measured but an idea

 

[Dissent]

What about building something like the Hammock King? You could mount it using 2 80/20 crossmembers on the Prinsu rack right? Use some sort of flexible or expandable steel pole that could mount into a bracket. The bracket would mount onto the 80/20 crossmembers. The bracket could be permanently affixed to the 80/20 on the roof. Then have the poles slide into a drilled hole in the bracket with the drilled hole being used to set the angle of the poles? The nice part about the 80/20 is being able to use the slot to mount the brackets. I am trying to think about how I could do this with my Gobi Stealth rack.




That is just simply a great solution. Wow I love seeing solutions like this.

Those are both intriguing solutions. The Hammock King concept is what I began thinking about when I was kicking this around.

 

[Dissent]

Not a very good rendering nor well measured but an idea

View attachment 1655410

I like this idea, the Prinsu is about 81" long if I recall. I think there are 80/20 hinge and corner solutions but locking them in place could present a challenge.

 

[mudgudgeon]

Hammock camper here! Check out the hammock campers forum, lots of stand ideas there. Here is one that I think would work really well for your situation:

Tensahedron Stand

Wow! Stuff like this just blows my mind.

Such a simple idea that looks like it shouldn't work.

Might look into making one. I occasionally have trouble finding suitably spaced trees in the sparse Aussie bush, or in camping grounds. This could be a good back-up.

I think that could be super easy to set up on a rack, set up mounting points for the bottom of the four poles, anchor one end to the front bumper. Stow the poles in the car, or in a tube on your rack.

+ 1 on checking out hammock forums. No shortage of hammock nerds there, so heaps of great ideas

 

[clx16]

Well I should have explained better with an additional drawing. They would not need to lock in place as they could pivot completely allowing you to adjust the tension of the hammock for more banana shape or tighter. You would attach the webbing with cam buckle from the top of the triangle down to the front/back of the rack (respective of the triangle you are attaching to), they would pull against the hammock which you would attach before folding out the triangles. if you look REALLY closely at the little 80 series you will see very thin lines looking like guy-lines pulling down. you would put very little tension on them if you wanted the hammock to sag way down to make a chair or tight for sleeping.

The triangles could have another tube (or square tubing) inside along the right-angle section allowing you to run another inside to extend even higher with just a snap safety pin passing through both tubes a various locations to adjust length. I think the shape would make this very strong and it would fold very flat allowing you to not add much if any height.

 

[ygthb]

I have often thought of adding a sleve to the front bumper and rear bumper that would accept rods like the hammock king. This would allow me to hang to the side of my rig. add an awning and you have cover.

 

[Dissent]

Wow! Stuff like this just blows my mind.

Such a simple idea that looks like it shouldn't work.

Might look into making one. I occasionally have trouble finding suitably spaced trees in the sparse Aussie bush, or in camping grounds. This could be a good back-up.

I think that could be super easy to set up on a rack, set up mounting points for the bottom of the four poles, anchor one end to the front bumper. Stow the poles in the car, or in a tube on your rack.

+ 1 on checking out hammock forums. No shortage of hammock nerds there, so heaps of great ideas

Yeah, I've been on the hammock forums for a few years. Lots of neat ground based ideas. The reason I'm focused on the roof is because I'm used to sleeping up there and the view is far superior to ground level. Better breezes as well. I have a solar panel up front so the diagonal hang may not work, cross truck is the direction I have to pursue to not stomp on my solar panel. It would be great to be dual duty; on the truck and then pop it off for on the ground work. I have 2 kids too so ideally, I'd have 3 setups; only 1-2 on the truck though. I started with the hitch idea, then went with the bumper corner pole concept but I don't have plate bumpers. I like being able to stay off the ground and not anchored to a land point either.

 

[Dissent]

I have often thought of adding a sleve to the front bumper and rear bumper that would accept rods like the hammock king. This would allow me to hang to the side of my rig. add an awning and you have cover.

I've seen that out here a lot. I don't have plate bumpers and reasoned out how to fashion a rear setup with the OEM bumper but up front there's nothing to support the bracket. The Eno Roadie is my alternative to accomplish this for the front tires but that's after I exhaust on top of the truck options.

 

[Dissent]

Well I should have explained better with an additional drawing. They would not need to lock in place as they could pivot completely allowing you to adjust the tension of the hammock for more banana shape or tighter. You would attach the webbing with cam buckle from the top of the triangle down to the front/back of the rack (respective of the triangle you are attaching to), they would pull against the hammock which you would attach before folding out the triangles. if you look REALLY closely at the little 80 series you will see very thin lines looking like guy-lines pulling down. you would put very little tension on them if you wanted the hammock to sag way down to make a chair or tight for sleeping.

The triangles could have another tube (or square tubing) inside along the right-angle section allowing you to run another inside to extend even higher with just a snap safety pin passing through both tubes a various locations to adjust length. I think the shape would make this very strong and it would fold very flat allowing you to not add much if any height.

Ahhhh...I see. I was looking at it on my phone at lunch. I would like to mock this up in the near future. My current stack of plywood is 1"-1-1/2" (thanks warpage!) and the 80/20 is only 1" tall. By running the 1020 bars (1"x2") that would be very strong. The only issue I have so far is trying to not step on my solar panel mounted just behind the sun roof. I may be able to figure out a way to turn this sideways, above the solar panel, and work on the extension setup you mentioned. Mounting another extrusion to the triangle verticals would be pretty easy facilitating and adjustable vertical to get that required 12' width.

 

[clx16]

Part of my mockup design flaw is the x-axis that would be hinged on your rack does not need to be the full width. and the Y-axis (verticals) could be full length, however not necessary at all if you make them telescoping at all. In fact, you would save weight (not that aluminum is that heavy) having them be shorter and function more as a stabilizing base.

You could post a picture of where your solar panel is situated. My solar panel is foldable and I just move it around with just the cord attaching to my solar charger. I will get something more efficient/permanent later.

 

[ygthb]

You could avoid the tie downs if once the triangles pivot up, you insert a pin or brace against existing hardware

 

[Dissent]

You could avoid the tie downs if once the triangles pivot up, you insert a pin or brace against existing hardware

I was thinking the same thing originally but I like the option of having the straps take care of that, takes the shear load off the proposed pin and opens up the flexibility of the system too.

 

[Dissent]

Here's the placement of the solar panel:

 

[Dissent]

Just realized, if I get rid of that white platform, I can move the solar panel to the rear.

 

[Dissent]

Part of my mockup design flaw is the x-axis that would be hinged on your rack does not need to be the full width. and the Y-axis (verticals) could be full length, however not necessary at all if you make them telescoping at all. In fact, you would save weight (not that aluminum is that heavy) having them be shorter and function more as a stabilizing base.

You could post a picture of where your solar panel is situated. My solar panel is foldable and I just move it around with just the cord attaching to my solar charger. I will get something more efficient/permanent later.

One advantage of a full length X-axis is multiple hinges for added strength. My platform came before my solar and when deployed it covered the panel. I wired in a "Y" so that I can add a set of folding panels if need be.