New trailer multi functional design concept

Discussion in 'Boat Design' started by Bartboat, Mar 7, 2013.

  1. Bartboat
    Joined: Sep 2012
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    Location: Ferndale wa

    Bartboat Junior Member

    I just repowered my 23 galvanized steel boat from a single 175 to twin 150 on a new full flotation bracket, we now are really overtaxing the trailer as the boat is 6000 lbs. My wife suggested making a utility trailer out of it, which was pretty good idea. However, we need to condense and consolidate stuff as we may be moving to smaller digs.
    How about a utility/car/boat trailer? I really think I could make an aluminum car type trailer work. The steel boat doesn't need specialized supporting structure. In fact, by placing the bunks out near the chine I might be able to design them tall enough they could be popped off and utilized as ramps in car trailer mode. The winch stand is far enough forward to be out of the way and could be used to winch a non running vehicle on. So, the two design issues I have turned up so far are, to keep this whole thing low enough and simple. (Non tilting and narrow). I would need to run the pontoon boat tires with the 10 inch rims. Also a third torsion axel would be required. But, this would also give me almost 10,000 gvr. So, what do you think about spinning the little 20.5 tires on the highway when we take the boat on a long road trip? Carlisle US makes them at a 1650 load rating. I love these low tires my four axel sailboat trailer but they don't see the highways either. Some people don't like the idea of small tires spinning so fast on the freeway if we do travel some. But there's always got to be some compromise eh? I haven't been able to turn up any actual fact that these pontoon, tent or snow mobile trailers have more bearing failures. What do you think?
     
  2. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    I think the idea is sound. I had that idea myself. I certainly wouldn't worry about tire diameter as the tires have been designed to withstand highway speeds and if one fails, you have five more tires to keep things under control (carry a hammer with you like the big rig guys). Lifespan of the tires will be less but trailer tires usually age and crack before ever getting close to wearing out the tread.
     
  3. JRD
    Joined: May 2010
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    Location: New Zealand

    JRD Senior Member

    I like your idea Bartboat, while it may take a bit of luck for all the different requirements to come together it saves space, some cost and probably licensing and insurance costs. It sounds like you have done your homework there but id like to add a few points to consider

    You will be at the weight where auto braking is required

    Is there a requirement to engineer and certify trailers over a certain load rating where you are?

    You will have thought of this already, but you will need an effective way of taking the boat off the trailer and storing it when you want the trailer for other duties

    Good luck
     
  4. Bartboat
    Joined: Sep 2012
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    Location: Ferndale wa

    Bartboat Junior Member

    Thanks Alan, that's cool you had the same idea too. Sure thought I could find something on the Internet. I keep wondering if I'm missing something . Appreciate the positive reinforcement. Bart
     
  5. Bartboat
    Joined: Sep 2012
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    Location: Ferndale wa

    Bartboat Junior Member

    Hi JRD, I recently read a fantastic book from one of your countrymen who built his own boat out of kuri logs he salvaged in the 1930's. He had to make just about everything on a very limited budget. Went around at night chipping excess tar off the road for enameling his hardware and rigging. Great read, truly inspiring. John Wray is the Chaps name.
    Thanks for your points. I'll be putting on disc breaks with the self stopping device. No engineering that I know of. It will have to be inspected by the state patrol though. And lastly we are lucky to have waterfront property so if I need the trailer for car hauling or utility chores I can just slip it off. You may be interested to see my 47' quad axel trailer I built with an articulating tongue for launching our 32' cat of the beach. It's on YouTube Bartdavis100.
     
  6. Yellowjacket
    Joined: May 2009
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    Location: Landlocked...

    Yellowjacket Senior Member

    You really need to rethink the tires that you are using if you are hauling upwares of 8,000 pounds. Do some searches on trailer tire failures. The only tires you can get are now made in China and are really crap. These tires are failing on my fellow Corvette racers rigs at an alarming rate.

    Whatever you do, don't run your tires at anything near their load rating or you are likely to be sitting by the road with blown tires more often than you can imagine. If you want to tow at highway speeds you absolutely need much bigger tires and brakes on each wheel. This is serious stuff, and you can end up in the ditch and dead if you cut corners on the rig. If you want to design and build it yourself, you need to do some research on big trailers and copy what works. Don't assume you can innovate much here, because things are done the way they are because the folks making those rigs don't want to be on the wrong end of a lawsuit.

    Here is a thread on the Corvette forum about recent tire problems with heavy trailers..

    http://forums.corvetteforum.com/aut...at-tires-are-you-running-on-your-trailer.html

    Hope this helps.
     

  7. Bartboat
    Joined: Sep 2012
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    Location: Ferndale wa

    Bartboat Junior Member

    Thanks for the links Yellowjacket. Yeah, just about everything is made in China. I've got well over 20% built in for safety. So, the tire should be running fairly easy. We haven't factored in the tongue weight either. The tow rig can actually support another 10% of load quite easily. I know these tires aren't ideal but should work and I really need a multi use trailer. I had some Les Scwab tires in the mid 80's that actually came apart after 500 miles. Firestone had issues too. So it can happen to anyone. If these tires can't carry 70% of their rated load, then I guess the dealer will be replacing them. I do have a bit of a back up plan if I find more info about these tires. I could run a bit larger tires and have them poke through the bed 4". In car hauler mode a large wide vehicle could just drive right on top of them. Then a cap could be placed back over them. One Problem is, those tire are probably Chinese and not rated as high as the smaller ones.
     
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