Smart car crosswise

[stolpsaddles]

Here are a couple of picture of the failed hing.. Broke the hinge casting.

 

[Brad & Jacolyn]

Guess there will be some inspections done because I believe I have the same ramps. Will unload tomorrow at 'The Ranch' in NM. 

 

Brad

[HERO Maker]

Thanks for the pictures of the failed area.  Will be looking closely for those specific areas on mine.

Wonder if Discount Ramps is suggesting anything in the way of strengthening that area if possible?

Thanks again for posting.

[Heavymetal]

On April 10, 2017 at 8:52 PM, stolpsaddles said:

The ramps where from Discount Ramps  

Aluminum Folding Smart Car Trailer Ramps - 2,000 lb per axle Capacity with the plate. I loosely bolt them to the deck.

I chose these ramps instead of the Big Boy II  ramps  because of the higher weight rating. I have used them for four years. When backing off the deck one of the hinges failed, sounded like an explosion. The right rear started to drop so I floored the accelerator and got the car off before it rolled over. The front of the care move left so the left tire missed the ramp on the way down and damaged the front air dam, center panel,left fender, ac rad, main rad and the plastic panel underneath. .I called discount ramps and they offered to sell me 1 or 2 ramps at a discount  because there was only 1 year warranty on those ramps.( the lighter weight ramps had 5 year warranty ). I sent them a followup email with photos of the ramps and asked for them to ship me 2 new ramps at there cost and I would cover the damage to the car. Called back a few days later to find out what they would do and they agreed to ship me 2 new ramps at there cost. Don't know why they failed, maybe I was rough unloading them off the truck, ( throw them on the ground from the deck )

Still don't know the $$$ damage to the car but the insurance is $500 deductible. Lucky no damage to the truck or any injuries. With some duct tape and glue and the car was usable with no AC

 

The whole front end including rad and lights and all fluid bottles is $699 on eBay this also includes the lower air dam and front rad and fender mounts. 

 

[Dollytrolley]

14 hours ago, stolpsaddles said:

Here are a couple of picture of the failed hing.. Broke the hinge casting.

 

Ok I've never been wrong before but..........(should stop typing now) .......but Ron, from your images it appears that the hinges are Extruded , not cast, but for the most part Extruded hinges tend to be very secure and constant in quality compared to sand cast hinges of like cross section.

Now I did not stay in a Holiday Inn last night but  did pass the Failure Audit  Course work in the lower 50% of the class so........anyhow one of the things that Structures Failure Engineers harp about with hinges are forces that compromise hinge integrity that were termed with very large worded report statements such as ..........Adverse-Inter-plain-Miss-alignment or other such gobblegook...........when us hillbillies out at the wreck site would just mutter that some BIG forces TWISTED the darn hinge at a weird angle across the extended face of the hinge.......

Hinges like to be hinges and they tend to function within design limits in the hinge function but IF the forces start to become concentrated in a twisting action at a unbalanced twist such as the ramp on the truck is lower on the left side of the ramp to bed surface and the ground end of the ramp is hovering off the ground due to a depression in the ground then the ramp AND the center Ramp Hinge will become highly stressed as the Smart car transfers it's mass (weight) onto the ramp surface thereby imparting a torsional vector into the ramp and likely forcing the lower bottom right edge into contact with the ground surface IF and this IS a BIG IF......IF the ramp deform plastically (Ramp takes a bow shape downward) and if stress are somewhat greater the ramp structure will exceed the yield strength of the ramp structure and the most compromised portion of the structure (Hinge) will fail............Classic structure chain of events to failure......

 

It's hard to really tell from the images but it appears that these ramp hinges are designed to be Hinge-Bound at the 180 degree open position to provide the needed limit to lock the ramp in a common beam position........if indeed this is the design the hinge is very likely the highest stressed portion of the ramps structure by far and any twist-out-of-axis of the hinge-pin-center line will impart much adverse stresses that would likely exceed the hinge design load ratings......

Now of course Steve K being a Sr Engineer has a couple of wiz--kid--engineers under him that could model these ramps on their smart phones and in two minutes could have a bunch of rainbow colored FEA images of the stresses suitable for framing at the ECR........

Being a hillbilly my two sets of ramps have no hinges..... but..... if they did have hinges I would have a "fish-plate" on each side of the hingeline extending at least 12 inches on each side of the hinge-pin axis..... cheep insurance...... most folks would think that my fish--plates were bolted on to make the ramp stronger but that's not why I would install the plates......the reason I would install the plates would be to allow a alternate load path for the torsional forces to flow AROUND the hinges and not compromise the hinges in a adverse manner.

 

Most lightweight hinged ramps are of two classes if you load them often to near capacity..........those that have yet to fail  and those that have failed.........without a alternate load path hinged ramps are subject to much compromise......

Drive on.........(Stress.......less)

[rdickinson]

I'm thinking there is a way to determine the cause of failure, type of break etc.

I have an idea of what caused damage to cabinets and millwork by the nature of the injury and impact.

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I typed this out a couple of days ago but lost contact with internet so it got saved, now I'm sending or posting it.

[stolpsaddles]

The other thing besides handling the ramps carefully now is that I look to see that the lower end of the ramp is filly sported and does not impart a twist in them when under load. Also try to use the center of the ramp and not one side more than the other, hard to do when the front is narrower than the rear for tire spread.   Sure is nerve wracking when using the ramps now.

I do not blame Discount Ramps for the incident and they where good to send me a replacement set at there cost.

Hopefully this will not happen again and other might learn for it  and be aware to handle the ramps with care.

 

[NoDirectionHome]

Dolly is right that the computer whiz kids could do that but, they're too busy working on the B-21 bomber at the moment (REALLY!) 
So here are my personal views.  If you have have ramps that fold in HALF  that's where the most stress is.  The middle of a beam with a point load usually would be thicker at the center and can taper towards the ends.  You (We) would all be better off with a 12' (I personally only believe you need 10') ramp that has a 6' or 7' center section with two 3' sections and two hinges toward the ends where there is much less stress when the rear (heavier) end of the car is in the middle of the ramps.
It's the height (2" for most) vs the length (6' for most) that creates the leverage on the hinge, so a 3" deep ramp would cut the load 50% and more than double the stiffness of the ramp.  

[rdickinson]

I need at least 12 ft ramps, even then I block up the dirt end by 3", dump the suspension and put a chunk of angle iron in the hinge to reduce breakover angle.....Even then I have to be careful the plastic underbody doesn't catch on the bolts holding the ramps on.

I put some underbody lites on the car and have caught both of the midbody ones so they will be coming off.

[Dollytrolley]

11 hours ago, NoDirectionHome said:

Dolly is right that the computer whiz kids could do that but, they're too busy working on the B-21 bomber at the moment (REALLY!) 
So here are my personal views.  If you have have ramps that fold in HALF  that's where the most stress is.  The middle of a beam with a point load usually would be thicker at the center and can taper towards the ends.  You (We) would all be better off with a 12' (I personally only believe you need 10') ramp that has a 6' or 7' center section with two 3' sections and two hinges toward the ends where there is much less stress when the rear (heavier) end of the car is in the middle of the ramps.
It's the height (2" for most) vs the length (6' for most) that creates the leverage on the hinge, so a 3" deep ramp would cut the load 50% and more than double the stiffness of the ramp.  

Ron indeed temps can be not much fun to deal with and center hinged ramps can have high stress factors even for the driver..........like I said in my earlier post now all of my ramps are non hinged one piece ramps but with a 20 ft cargo I have plenty of room for long ramps. 

 

IF....I had center hinged ramps, I would attach 3x3x1/4 x36 inch long angle fish plates bolted centered at the hinge line on each side of the ramps with the angle leg under the bottom beam of the ramp so that the hinge would be under very little stress since the angle members would create a alternate load path.

With proper bolt installation the angle members could handle the loads even with the hinge pins missing.......essentially you would have singe beam ramps with the angle splices installed.......unbolt a few fasteners and poof you have hinged ramps again.......simple insurance.......Dr Pepper time again....

 

Drive on.........(Drive on.....one piece ramps)

[Brad & Jacolyn]

Well you certainly got us thinking. before I unloaded yesterday I closely inspected the ramps and could not find anything that did not look perfect. I even pulled the pins and inspected them (looked perfect) and lubed before putting back together. But the pucker factor was a bit higher after seeing your pictures.

 

Brad  

[SuiteSuccess]

If I was driving my smart on and off would give me a pause.  Think I'll just continue winching an empty car on and off. Rather the car sustain the damage than me or my wife. 

[Pete Kildow]

On the width. Check your 5th wheel, and see how wide it is at the widest points.. Then you will see that 104" Smart is within or the same width as your RV. Most of the bigger 5th wheels. When moved commercial ( Kid I know got caught) towing Rv's. Have to to have an over width permit to pull. Even our old Truck Camper, Okanagan 811-SL was 104" wide then you had a cover over the slide-out. So guessing 107 to 108" in a truck camper.

I have not measured our Heartland LandMark Key Largo. Other then to see it was a full 102 on the body. Then slide-outs stick out some on both sides. Then awning covers over those slide-outs. Along with 17ft Awning on the pass side.

 

So as you can see your over width to start out. Unless those awning and slide-out lips are like mirrors on trucks. And not included in the 102 width.

[Big5er]

2 hours ago, wild wolf products said:

So as you can see your over width to start out. Unless those awning and slide-out lips are like mirrors on trucks. And not included in the 102 width.

They are not included (at least not in my state)...and the smart is closer to 106, not 104.  

Sec. 622.903. WIDTH LIMITATION ON CERTAIN RECREATIONAL VEHICLES. (a) In this section:

(1) "Appurtenance" includes an awning, a grab handle, lighting equipment, or a vent. The term does not include a load-carrying device.

(2) "Recreational vehicle" has the meaning assigned by Section 522.004.

(b) A recreational vehicle may exceed a width limitation established by Section 621.201 or 621.202 if the excess width is attributable to an appurtenance that extends six inches or less beyond a fender on one or both sides of the vehicle.

[GeorgiaHybrid]

7 hours ago, SuiteSuccess said:

If I was driving my smart on and off would give me a pause.  Think I'll just continue winching an empty car on and off. Rather the car sustain the damage than me or my wife. 

Just wait till your winch cable snaps like our did in Texas a couple of weeks ago. Had fun chasing down the car. Lesson learned? Inspect that stupid cable every time it is used.

[Alie&Jim's Carrilite]

5 minutes ago, GeorgiaHybrid said:

Just wait till your winch cable snaps like our did in Texas a couple of weeks ago. Had fun chasing down the car. Lesson learned? Inspect that stupid cable every time it is used.

 

Check into http://www.amsteelblue.com/  We used on rigging, winches, windlass, and other can't fail applications.  

 

[billr]

Our steel cable after 4 years started the get worn and break strands. It would bind up and wrap uneven since new  

Switched to the Syn rope and no more issues. Winds up perfectly. No damage to rope except its fading a bit.  Its been in use now for 4 yrs  

 

 

[GeorgiaHybrid]

Bill,

Ours came with synthetic rope and has been on the winch less than a year. Looking at the rope, it must have gotten pinched between two wraps on the layer below it. I was very flat in that section that failed.

[hone eagle]

The few times we winch the wife rides with it ,a broke cable does not bear thinking about .

By myself I drive it up ,and kudos to the OP for admitting "throwing the ramps off the deck" is not best practice, they are awkward to move around for sure,I put tiny casters on one end so they roll across the deck .

[SuiteSuccess]

9 hours ago, GeorgiaHybrid said:

Just wait till your winch cable snaps like our did in Texas a couple of weeks ago. Had fun chasing down the car. Lesson learned? Inspect that stupid cable every time it is used.

Dave,

Good lesson.  I use Amsteel Blue synthetic.  I think it's 12,500 lb. That was one of the reasons DW was riding the car down in case of a failure.  May just buy a short piece of thicker rope and use as a tether in case winch rope broke so car wouldn't roll more than 10'.  Alternative is to somehow reinforce hinge point.

[Big5er]

9 hours ago, GeorgiaHybrid said:

Bill,

Ours came with synthetic rope and has been on the winch less than a year. Looking at the rope, it must have gotten pinched between two wraps on the layer below it. I was very flat in that section that failed.

Synthetic is not subject to being flattened like steel cable. It doesn't get crimped like steel...BUT dirt and sand can get into the cable and cut it as it twists and flex. Synthetic needs more cleaning and maintenance than cable.

[Brad & Jacolyn]

Just a question. What does OP stand for? I keep seeing it used.

 

Brad 

[Jack Mayer]

OP = Original Post (or poster)

 

[Dollytrolley]

Geez guys I gotta give Dolly-tha-Paint-horse a extra carrot the next time she Auto-Loads or ..... Auto-Unloads out of the toy hauler module ........not only does Dolly trot up the ramp but then she pivots her butt 90 degrees to the right so that she rides sidewise sorta like the not-so-smart-cars.......

 

Now don't run out and buy a bunch of horses to replace your Smart cars because if yo think a Smart car falling of the ramp is fun trying to load a horse that has decided it does not want to be loaded.......bad juju.....

 

Dont try this at home.....but.....I forgot the ramps one day and so.......just face the old Honda Quad between the drivers and run the winch cable over to the other side of the bed and wad a few shop rags to pad the bed corner where rather cable runs over the corner of the bed then stand well back an winch the quad UP and UP over the bed corner onto the bed........

 

So how much insurance do you have to get in order to have the wife be the "safety-driver" for the runs of the Smart car up and down the ramps????

 

Dollymomma has no need to ride Dolly into the toy hauler module......

 

Pretty sure that I might get a lump or three on my head if I would having one of Johns "trunk monkeys" ride Dolly up and down the ramps.......might be a real .....Rodeo ..........

 

Drive on.......(stay outa tha way of......tha Smart cars falling)

[Brad & Jacolyn]

Thanks Jack.

Brad