Community Forums

saxmandan · 04-11-2020, 07:02 AM

I just bought a folding Porta-Bote, and I thought the best place to transport would be the roof, held down my racheting straps. Side mount brackets is an option, but I really don't want to mount it on the slideout. I'm thinking of using the surface mount D-rings. My question is, what is the best way to attach the D-rings to the roof. Should I screw to beams (if I can locate them), or is the aluminum roof strong enough to just screw into? I was also thinking large rivets might work also. Any ideas?

hypoxia · 04-11-2020, 07:59 AM

I had a 14' Porta Bote which I mounted underneath a 5th wheel and then under 40' Revolution motorhome. My current coach is much lower to the ground and is not a good candidate for an under mount. I just drilled holes through the cargo compartment and used two pieces of angle iron to hold it. It worked well.

If you use the roof mount I would use screws. Getting it up there will be a job!

LJowdy · 04-11-2020, 08:03 AM

I looked at a photo of the boat collapsed and it looks like it wouldn't cause too much wind drag. The aluminum roof probably isn't very thick but I'd build some kind of a deflector that goes over the front of the boat so air goes over the boat and not under the boat. Try for studs but if you can't find them I'd reinforce the area's with a t 1/8 th or 1/4 inch thick aluminum plate securely riveted to the roof then use some kind of an expanding nut or moly bolt Be sure to cover the plates with Dicor to prevent leakage. Any mount points such as the "D" ring also need Dicor. I have a feeling that the straps will vibrate due to wind blowing over them and it may cause you to go insane from the noise but that's just speculation based on trucks passing me with their load tied down with ratcheting straps and I can hear the straps vibrating.

Roy-c · 04-11-2020, 08:17 AM

I would mount a track on each side of the roof. maybe a track used on a sailboat for the sail lines. would be easy to seal against the roof, give you an infinite number of attaching points if you decide to tie something else down on the roof, designed to be out in the weather and low profile. You maybe could get it for reasonable at a marine flea market or used boat parts store / salvage yard.

Winemaker2 · 04-11-2020, 10:02 AM

Do you two a toad? If so on the road roof would be a LOT easier to set up (racks avail) and load / unload.
Getting a folded boat up on an RV roof wouldnt be easy!

saxmandan · 04-12-2020, 06:49 AM

Thanks for all the great advice. A lot to think about. I hadn't thought about the wind deflector, but after examining the folded boat I think it may not be needed. The company recommends when using roof racks to mount the boat on a car top with the bow facing forwards. Looking at the boat, you can see where it doesn't have much wind resistance at the bow. I think some sort of a slip-on cover for the bow will cut the resistance even further. That said, if I could find a wind deflector to cover that bow section, about 8 inches high, I'd buy it. The boat is 24 inches wide when folded, so anything about 26" wide by 8 inches would work. I supposed I can fabricate it from sheet metal.

As far as mounting on the bottom of the coach, there just isn't enough room. Also, I don't tow, so mounting to the tow vehicle is out.

As far as noise from the oscillating straps, they will be tight and not much will be in the open air, since the folded boat edges is just a few inches off the roof.

Getting it on and off the roof took some thought. I had planned on using a small Harbor Freight electric winch, which I already had, but decided it was over-kill, plus the cable scrapping on the edge of the coach is a real problem.
I had an unused hand crank winch from a small boat trailer. I loaded it with 1" nylon strapping, which is rated at 900 lbs. The boat is only 83 lbs, so it should work out ok. It will be anchored on the right side of the coach, going around the rear wheel. A wide strap will be used to protect the coach's roof edge.

As far as anchoring the boat down on the roof, I'll use 4 straps, and some sort of a block at the rear, to keep it from sliding rearward.

Luckily, I plan to use this at a campground I'll be at for one month. Not the kind of thing I'd want to mess with for a weekend trip. Also, this trip is not until next winter, so I have lots of time to do the installation and testing.

LJowdy.... good advice on adding the mounting plate. I don't know how to go about finding studs. Too bad there's not a stud finder for aluminum!

jacwjames · 04-12-2020, 09:13 AM

I had a Class C that I carried 2 sea kayaks on the roof all over the eastern USA. I did not want to drill through my rubber roof so I made some attachments in front of the rear wheels. I used some heavy L brackets I bought from Lows and bolted them to the chassis frame, they stuck out maybe 3 inches. I put eyebolts in them so I could used them as tie downs. On the edge of the roof I used a couple of the canoe carrier foam blocks that I routed the straps through, this protected the edge of roof. This was to secure the front of the kayaks. I made 4 large foam blocks that cradled each kayak and kept it off the top of the roof. I made a piece that attached to each end of the kayaks, this kept them separated on the roof. On the rear I was able to let the end of the kayaks sit out basically right above the trailer hitch and ran a tie down there plus secured the back of the kayak to the roof ladder.

I hauled these probably 40K miles from Wisconsin, Maine, Florida and back to TN over a 10 year period. People would often stop what they were doing and watch how I got the kayaks on and off the top of the roof. Only mistake I every made was leaving an inflatable float in the on kayak and it blew out.

Winemaker2 · 04-12-2020, 05:51 PM

Re finding alum framing...
If you find the right conditions with a cool night when dew forms you may be able to see there the framing is.
I took some pics of my sidewalls when I noticed the framing outline dry with dew in between.
The heat transfer and skin temp is different and obvious when conditions are right.
Newmar also provided me with framing drawings for the bath area when requested to mount accessories.

rodekyll · 04-12-2020, 05:59 PM

If you don't tow, why not fab up a hitch-mounted variation of a bicycle rack? It would be low, vertical, maybe just a crossbar off a hitch post with a vertical fork on each end. It's not a lot of weight to wrangle. Drop the boat in the forks and go.

saxmandan · 04-12-2020, 06:27 PM

Interesting ideas guys. I'll take a look at the rear of the rig tomorrow, although if loading and unloading using my system with the boat winch works fine, I like the idea of getting it out of the way and up on the roof (good song, BTW!). I'll check out to see if I can see the dew outline to find the frame. I definitely would have never thought to try that.

BTW, I upgraded to 2" nylon strap on the winch, with a breaking strength of 2800 lbs.

Winemaker2 · 04-13-2020, 06:26 AM

Good thought on rear mount. I once saw an RVr with a rear mounted canoe. Creative guy. He designed and built the cedar strip canoe in 2 pcs such that one piece would nest inside the other. Both essentially had a flat "stern" and when connected together formed a full size canoe (with a bulkhead slightly off the mid point).
Wish a took some pics.
I've often though he should have patented it and tried to sell a production version.
Either way this alum tube stock & fittings might come in handy. I've built some stuff out of pieces I've had on hand from a salvage job.
https://8020.net/

saxmandan · 04-13-2020, 04:24 PM

As far as my situation goes, I think the rear mount would cause my height clearance to go from 12'6" to around 14'. If I had bought a 10 footer, that would have been more doable.