Designing a small car trailer. VERY crazy design and discussion with pictures...

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So, i came across the following pictures on GRM facebook page...which got me to thinking... could i build one of these.   the main part is the design of the trailor.i came up with this idea (dont have CAD on my computer at work so be patient)This is also an idea and by no means scaled even part to part as im sketching an idea in paint.Would this design work as im thinking and allow to still have suspension?Now... i have a Mazda Miata that i want to design the trailor to... this makes the load weight 2x what is pictured...so i need to calculate the moments about the axle to determine if the weight of the car will even allow a person to lift it!  This is a bit of a complex calculation too since the car weight isnt centered over the axle, or the pivot point.Any engineers/designers care to share input or other draft ideas?Matt
Reply:check out this style of trailer,  often used for various construction equipment,   rollers, bobcats etc. may give you some other ideas http://www.air-tow.com/trailersinaction.htmlTiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:so it's pivoting off the shackles? how much torque does that put on the shackles when lifting? something has to twist when lifting the deck back up. and thats going to be the weakest link. unless it's two people lifting both sides at the same time.How is the front of the spring attached to the trailer? just a pin? that can move freely in the spring eye and wear both the spring eye, and the pin?I would check with the state patrol to find out if it's even road legal in your state/any states you would plan on taking it too.more weight is just easily handled with a longer folcrom (sp?). Or other words, a longer bar. another thing to consider is the extra weight on one side when the other side is already up.Why not just use a tilt trailer, or drop axles to lower the deck height?There are no problems. There are only solutions. It's your duty to determine the right one.Hobart Handler 210Airco 225 Amp MSM Stinger
Reply:The same basic idea is used for expensive ice shacks. Only difference is they are controlled by a winch with cables. No pulling down on the lever to lift it up. Also saw one on youtube that used airbags to drop and raise it.
Reply:Originally Posted by shlammedSo, i came across the following pictures on GRM facebook page...which got me to thinking... could i build one of these.   the main part is the design of the trailor.i came up with this idea (dont have CAD on my computer at work so be patient)This is also an idea and by no means scaled even part to part as im sketching an idea in paint.Would this design work as im thinking and allow to still have suspension?Now... i have a Mazda Miata that i want to design the trailor to... this makes the load weight 2x what is pictured...so i need to calculate the moments about the axle to determine if the weight of the car will even allow a person to lift it!  This is a bit of a complex calculation too since the car weight isnt centered over the axle, or the pivot point.Any engineers/designers care to share input or other draft ideas?Matt
Reply:This is a really neat idea. I see some problems though. 1. In your drawing you have a shackle at the rear pivot. The rear mount should have no link, just a pivot like the front eye on a leaf spring, except more rigid. I'd think poly bushings at least 8" wide. 2. The front pivot should have a shackle or a sliding mount like the trailer pictured. 3. It seems that the trailer pictured has near the maximum length on the lever (it's as tall as the guy operating it), therefore to get more leverage to lift your heavier car you must make the pivot side shorter, thereby shortening the throw and suspension travel. Or employ some force multiplier like pulleys or a winch. From here I can't tell how hard that guy has to push to lift the car.Ian TannerKawasaki KX450 and many other fine tools
Reply:Thanks for the input guys!I never thought of putting the shakle on the front!  that would would much better.I believe that you need some sort of shackle on this setup.  Im not familiar with how the slide links work on leaf springs, but that sounds dangerous if you hit a large bump and that spring unloads.
Reply:UH..... in forty years of dealing with cars and stuff I have never seen the shackle in the front... there may be a reason for that... hitting pot holes or whatever might cause more out of alignment of the axle ( might wear tires more...or feel squirrely all the time )  if the fixed pivot is not at the front.... something to research first I suggest.....Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:Originally Posted by GBMUH..... in forty years of dealing with cars and stuff I have never seen the shackle in the front... there may be a reason for that... hitting pot holes or whatever might cause more out of alignment of the axle ( might wear tires more...or feel squirrely all the time )  if the fixed pivot is not at the front.... something to research first I suggest.....
Reply:lots of axles have the shackles on the front. something else you can think about is a slip spring like this.http://www.easternmarine.com/em_store/leafsprings/with that, I would consider putting the eye on the front, slip on the rear, spring mounted just outside the deck with the  sliding mount able to recess into the bed so you put a bar on the spring, pry it down, push in the mount, then lever the spring up past the deck. with the prybar removeable you can have a longer bar than the trailer is long of you want.Dynasty 200DXPassport plus w/ spoolmate 100victor 315c oxy/(act and prop)Miller digital elitemilwaukee power tools
Reply:Here is my question how does this design benefit you over a conventional trailer? Why cant you just use a regular one? Please dont consider this a smart azz question its intended that way just wondering.Miller 211Thermal Dynamics cutmaster 42
Reply:Originally Posted by blowinholesHere is my question how does this design benefit you over a conventional trailer? Why cant you just use a regular one? Please dont consider this a smart azz question its intended that way just wondering.
Reply:Torflex axles or stubs would be my first choice for that application. Google it if you haven't heard of them before. I'm guessing a Miata is still 1500 lbs or more, so lifting it by hand power would require a significant mechanical advantage. Likely a lever won't do, a hand winch is the only thing I can think of. I would go electric or hydraulic, but cost may be a concern.Be safeJasonXMT 350 MPA Dynasty 280DXSuitcase 8RC / OptimaSpoolmatic 30AThermco Ar / C02 mixerAssorted O/A gear
Reply:For what it will cost in material..Tools if you don't have them...Labor..Frustration...Time...You could just buy a used much better one for less..Maybe not the same design but......zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:[ame]http://www.youtube.com/watch?v=qZpizi8Kj_A&feature=related[/ame]Those who say it cannot be done should stay out of the way of those who are actually doing it.
Reply:Originally Posted by DSWMy guess is because of the extremely low ground clearance shown in the car in the pict. We used to have a Lotus and the low ground clearance caused a lot of issues with steep abrupt grade changes like ramps. That made the car difficult to load on a trailer with "conventional" ramps without damaging the vehicle. The advantage with this design there's almost no ramp. Note that rear "spoiler" that hangs out the back. On any conventional ramp that would hang up and get damaged. On our Lotus, it was the rear of the tranny that protruded from the back and was damaged on several occasions by even potholes on the road if you dropped a rear tire in a large one.
Reply:http://grassrootsmotorsports.com/pro...ailer-legrand/
Reply:Originally Posted by sandersd
Reply:Personally I'm not into riding low to the ground. Just not my thing. My question is this. Why spend the time, money, and effort on an design that is questionable at best? If approach angle is a concer, it could easily be delt with with a tilt bed trailer coupled with custome extention ramps. Custom ramps could be as long as you needed to account for the angle needed. up to doubling or tripling the length of the trailer. This would bring down the approach angle and accomodate any low slung rig. you'd have a trailer that you know is safe to haul down the highway, and still get the chance to build something (custome ramps). Building something just for the sake of saying you did, or you can, will just get you a spruce goose in the end. something that is a marvel of technology, and human ingenuity. but completely impracticle and not worth the money put into it.There are no problems. There are only solutions. It's your duty to determine the right one.Hobart Handler 210Airco 225 Amp MSM Stinger