Kayak Rack on Top of a Traditional Teardrop

[shootr]

So I'm still deep into the theoretical designing of my eventual 4'x8' traditional teardrop project. Question about roof loading parameters:

I have two "sit-on" plastic kayaks that normally ride in the bed of the Tacoma, with a drywall hitch support to catch the overhang. That won't work if I tow a trailer, and I don't want to put a roof rack on the truck.

Currently wanting to use (1/4" ply / 1" styrene sheet / 1/4" ply) composite wall construction, with the usual 1x2 supports between them for the roof. The exterior would be sprayed on bedliner material to seal and weatherproof. The kayaks and rack would weigh 150lbs. static load. Add the stress of 60-65mph road wind and the load seems pretty substantial.

I know composite construction can be pretty strong, I'm figuring surface gluing and screwing the wall sandwich together with interior ribs to add more strength. Adding an internal lateral shelf/cabinet at the front, and the galley cabinets in the aft to keep side-to-side strength up, does it sound like the walls would be capable of enduring the roof load, or should I be beefing things up more?

Thanks!

[doug hodder]

If you are doing composite construction...I'd put in a beefy piece of material that will really hold a fastener at those points that you want your brackets to attach to. A side mount type bracket might be best as it would carry the load down the wall to the floor/frame rather than onto the roof. In my opinion, I'd think that a roof mount system could be a problem. Others opinions may vary. Doug

PS...are you going to be able to open up that galley hatch with them loaded on?

[shootr]

If you are doing composite construction...I'd put in a beefy piece of material that will really hold a fastener at those points that you want your brackets to attach to. A side mount type bracket might be best as it would carry the load down the wall to the floor rather than onto the roof. Others opinions may vary. Doug

Hi Doug. The rack I'm looking at sits on the edge of the roof/wall joint. So the weight would be on the sidewalls, but I do need to plan on having the blocking in the right places! You think maybe something like oak in those places vs. pine? Both for the securing points of the rack, and vertically to carry the load to the floor/trailer? Another item on the "do not forget" checklist. Thank you.

EDIT: No, they'll come off first thing to clear room for the hatch, they're 12' and I want good head room at the galley. I have a dolly for moving them to shore and stuff. I also have a locking mechanism to chain them to a tree or bench when we're hiking. When we camp, we don't usually move around too much; set up for a weekend and then back home. Plus they'll have to move anyways, to clear the eventual roof vent/fan.

[doug hodder]

I'd do a hard wood...you posted before I added my last question...are you going to be able to open the hatch with them on the roof? Could be a hassle if you had to unload them all the time. Doug

[M C Toyer]

Have you considered a frame completely external from the teardrop itself thus avoiding the attendant problems of attaching anything to the walls or roof?

For example, a welded and corner braced 1inch square aluminum tubing ladder-type rack that could slide into either receiver hitches or slightly larger tubing permanently mounted to the underside of the trailer frame. The top of the rack would probably also have to slide out it an smilar manner. That may even be designed to slide far enough to open the hatch without unloading the kayaks. It could also be used as an awning support with or without the kayaks onboard.

See the concept here: http://www.tnttt.com/viewtopic.php?f=40&t=50949 although this was done with wood the principle is the same.

You said you didn't want a roof rack on your truck but what about a ladder rack or just a low back crossmember of a ladder rack? That way you could load the kayaks in the bed nose down and elevate the rear to clear both the tailgate and the top of the teardrop.

My kayak and luggage rack is mounted to the sides of my trailer and does not touch or rest on the roof in anyway even though I would feel quite comfortable walking anywhere on the roof or the rack, Where the side supports are attached the wall is two layers of 3/4 plywood which extends all the way to the floor and frame.

M C

[shootr]

I have one of those hard covers for the truck bed, so I can't use a rack with it.

I dig the exterior support idea, especially the dual use part of being an awning support. It's the look I'd have to figure out. That one is a little too "bold" for my taste. I'm not a trailer diva, function will always be the precedent over beauty - but I'd have to figure out something a little more aesthetically pleasing than that example.

It's a cool line of thought, though - now I have something else to roll around my empty head - the awning support use is something I do want to incorporate somehow - like an exterior changing/privacy area. I saw one guy use large PVC pipes installed laterally that pulled out when he wanted and then he hung the fabric on it. Don't want to penetrate the shell that much though.

Glad I'm not planning on breaking ground until the fall, so much to consider!

[shootr]

OR...!!!

Maybe by using vertical oak pieces in the sidewall, they would protrude past the roof in four points, enough to provide an anchor point for two cross braces to be pinned to them - could they be sealed well enough where they penetrate the roof with the bedliner?

OR...

Use conduit. Picture if you will...

Weld threaded conduit cap into the trailer frame.
Leave "races" in the walls for conduit to run through to the ceiling and above.
Mount the walls traditionally.
Drop the conduit through the races and screw then tight.
Using elbows and more conduit create the cross pieces.
When camping, undo the cross pieces, turn two of the elbows 180 degrees, put the crosspieces back in, and have extra elbows/conduit to be legs for the awning?
Same challenge sealing the conduit so water doesn't leak into the wall...

Dreaming is fun...

[M C Toyer]

[quote="shootr"]I have one of those hard covers for the truck bed, so I can't use a rack with it.

Gotcha.

I have a Ford Explorer Sport Trac - the bed is only 4 foot long and it has a factory steel hard cover that hinges in the middle so there was no way at all to carry my kayak in the bed. However the cover finish is somewhat like a bed liner and scratch resistant. The cover is strong enough to stand on and my rear window opening is about 32 inches wide so I just put a piece of foam rubber on the cover, slide the kayak partly through the window, and tie it down. The kayak back overhung the bumper about two foot but I had a bike rack mounted to the receiver hitch that is about that far back anyway. Before I built the roof rack for my trailer the kayak was well ckear of it anyway and I can still carry it or an extra the same way,

I think that was bobhenry in a recent post that had the extendable pvc awning rack. I like that concept because it looks like the receiver tubes are completely sealed and they mount through the sides so nothing rides on the roof. Taking that concept to my example of a ladder rack
two or three of the roof spars could be tubes that extended slightly past the sides of the trailer and those could be the receivers rather than going all the way to the bottom of the frame. The side walls could be reinforced directly from those spars to the floor / frame with the verticle framing within the composite wall.

Do you plan to carry the kayaks flat or on edge with an inverted T brace in the center?

Thinking a step farther if you carry them on edge you could hinge the sides of the rack where the kayaks could be flipped out to permit opening your galley hatch without completely removing them.

Where do you carry the dolly for the kayaks? Is it like the mitey-mites, just a pair of wheels on a small foldup frame that straps to the kayak? I built a tongue for mine out of pvc and made a pvc hoop to replace the straps. I always had a problem with the straps slipping if I pulled by the kayak. With the tongue I pull directly on the wheels so nothing slips. My current kayak is a sit in that I rigged with a battery powered trolling motor

[shootr]

I have one of those hard covers for the truck bed, so I can't use a rack with it.

Gotcha.

I have a Ford Explorer Sport Trac - the bed is only 4 foot long and it has a factory steel hard cover that hinges in the middle so there was no way at all to carry my kayak in the bed. However the cover finish is somewhat like a bed liner and scratch resistant. The cover is strong enough to stand on and my rear window opening is about 32 inches wide so I just put a piece of foam rubber on the cover, slide the kayak partly through the window, and tie it down. The kayak back overhung the bumper about two foot but I had a bike rack mounted to the receiver hitch that is about that far back anyway. Before I built the roof rack for my trailer the kayak was well ckear of it anyway and I can still carry it or an extra the same way, It's the wife's truck, technically, but the cover is too nice and color matched to mess with, and I like being able to lock up gear in it. Plus kids in the back seat, leaving the window open, etc. just isn't a solution for me.

I think that was bobhenry in a recent post that had the extendable pvc awning rack. I like that concept because it looks like the receiver tubes are completely sealed and they mount through the sides so nothing rides on the roof. Taking that concept to my example of a ladder rack
two or three of the roof spars could be tubes that extended slightly past the sides of the trailer and those could be the receivers rather than going all the way to the bottom of the frame. The side walls could be reinforced directly from those spars to the floor / frame with the verticle framing within the composite wall.I haven't given up on this idea either, it is an elegant execution if I can come up with a final design and materials that please me structurally and aesthetically

Do you plan to carry the kayaks flat or on edge with an inverted T brace in the center? Probably flat, as they would be able to sit side by side, and I'd like the rack to stay as vanilla as possible so it can be repurposed depending on the mission, so to speak.

Thinking a step farther if you carry them on edge you could hinge the sides of the rack where the kayaks could be flipped out to permit opening your galley hatch without completely removing them.

Where do you carry the dolly for the kayaks? Is it like the mitey-mites, just a pair of wheels on a small foldup frame that straps to the kayak? I built a tongue for mine out of pvc and made a pvc hoop to replace the straps. I always had a problem with the straps slipping if I pulled by the kayak. With the tongue I pull directly on the wheels so nothing slips. My current kayak is a sit in that I rigged with a battery powered trolling motor My dollies are PVC ones I made from an idea I saw on Instructables, with Harbor Freight balloon tires. They come apart enough to stow in the kayak when transporting, lashed under the ratchet straps. With bicycle grip-tape, they don't slip when wheeling to and fro.

[Forrest747]

Crunched the numbers on teh thickness of your wall and using 1/4 inch inside out you are looking at 1300 pounds per wall. It drops a little if you go with 1/8 inch interior. placing your interior solid framing at the rack hardpoint will increase to over 2000 lbs per wall.

[angib]

Yeah, 1/4" ply sandwich will just about carry an elephant - two kayaks is no problem at all. All you need to watch out for is that attachment points are strong enough, as others have said.

Fix to the sidewalls and put a 6" x 6" solid pad between the skins where the rack attaches and it'll be strong enough that you could roll the teardrop onto its roof with no problem.

[shootr]

Sweet!

I take it those numbers (forgive me if the terminology is inaccurate) are the maximum loads the wall can take vertically (in compression) with a load placed atop it and secured to hardpoints embedded inside the wall? With 2000 being if a hardpoint is supported by a vertical solid wood piece from the trailer to the top hardpoint?

God bless engineers!

[Forrest747]

Sweet!

I take it those numbers (forgive me if the terminology is inaccurate) are the maximum loads the wall can take vertically (in compression) with a load placed atop it and secured to hardpoints embedded inside the wall? With 2000 being if a hardpoint is supported by a vertical solid wood piece from the trailer to the top hardpoint?

God bless engineers!

That would be correct. that is the point directly above teh wall. if you build your roof out of tissue paper than you may have issues.

Fee for services will be a 6 pack; 16 to 21 ounce beverage chilled perferable something Jimmy Buffett would enjoy.

[shootr]

Going to have to hang tight, Moab and parts your way aren't until 2014, as for now - Yosemite is next!

[rowerwet]

I put these stainless bow eyes on my tear for attachment points for my side tent (which hasn't happened yet) they make great tie down points as well. the boat on the roof is not that heavy as it is only 8' long and made from 1.5 sheets of 1/4" plywood (I can carry it over my head with my arms fully extended, never weighed it though) the canoe blocks were resting on 1x3 spars that are fully glued to the 1/4" roof and walls with PLpremium everywhere they touch. After a couple hours of driving I found the blocks had moved slightly and were just on the plywood, but no problems to the plywood. I have plans for a two person boat http://www.duckworksbbs.com/plans/jim/l ... /index.htm which will be heavier.
it may not even fit on the roof of the tear, but if it does I will be making a rack out of ETM that mounts to those bow eyes.
As for opening the hatch with the boat on the roof this worked for an 8 foot boat, longer would probably work if the rack was made with fore and aft rails the same height as the side to side ones. I did the sideways boat to allow full access to the trailer to finish the 110v wiring at my in-laws house. I found I had to remember to duck, but my wife didn't.
I built my walls with 1x2's flanking the doors that run top to bottom for carrying roof mounted loads but also have a full 1x2 running around the perimeter of the wall, sandwiched to the inner and outer skins of 1/4 inch ply. the bow eyes are through the perimeter frame so I'm not to worried about loading them to much.