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Smart car width for deck planning


Brad NSW

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Designing deck plan and wondered what you used for Smart car width?  From the attached picture, if you fold mirrors in, it looks like you can use 62"' instead of 69".

Did you also use 48" from center of 5th wheel pin or did you give yourself 3-4"  more (51-52") for flex in uneven terrain?

Right now I'm using 69" for Smart and 52" clearance from 5th wheel but this makes the depth of my Drom pretty narrow. 

I'm thinking of:

1.  Going to 48" clearance to pin (how many times do you ever jackknife the rig).

2.  Using 65 for Smart width.

Thought/feedback/insights from your experiences?5ad8b342a0323_Smartdimensionsmirrorsfolded.jpg.c6fe2018dc8c79b69e7ec73c65efed47.jpg

Thanks in advance!

 

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2010 Freightliner, DD15 Eaton Ultrashift, 2015 New Horizons 5th Wheel.

Occupants - Dena/Brad/Hershey    BLOG LINK

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"Consider a steep uphill where the front cap on the fifth wheel tilts towards the Smart.  You should do a proper layout.  You basically need the width of the Smart + the 51" width of the trailer at 90 degrees to the truck + the minimum clearance you dare to use considering the above.  (I used 10 inches)

"There are No Experts, Do the Math!"

2014 Freightliner Cascadia DD16 600hp  1850ft-lb  18spd  3.31  260"wb
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Taking it out this weekend to the desert. 

If I put the truck in a series of decreasing turns till I hit 90 degrees, and drop a plumb line to the deck from the corner of the 5er nose each time.  That would mark the "flat ground" arc of the nose on the deck.  From there I'd add a safety margin. 

NoDirectionHome, sounds like you use 10" for this margin.  QUESTION:  Anyone use or recommend anything else (+ or -)??

For you who have done this for years, is jack-knifing (with the smart car still on) something you've ever had to do?  Never came close in 8 years with a 1-ton but I've got no experience with these big boys!

Bikes ride inside 5er, Lockmup but great point!  I know some who have them on the hitch. 

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2010 Freightliner, DD15 Eaton Ultrashift, 2015 New Horizons 5th Wheel.

Occupants - Dena/Brad/Hershey    BLOG LINK

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Do yourself a favor and take a measurement with the rig at 45 degrees.  You might be in for a surprise.  It's all been discussed here in the past year.

KW T-680, POPEMOBILE
Newmar X-Aire, VATICAN
Lots of old motorcycles, Moto Guzzi Griso and Spyder F3 currently in the front row
Young enough to play in the dirt as a retired farmer.
contact me at rickeieio@yahoo.com

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57 minutes ago, GlennWest said:

Half the width of camper is where it goes. 

Plus a margin for tilt.

I am 127" off of my drom box.  I feel I can stay there even with the 16-17 model.  But a few more inches wouldn't hurt!

Plan for that real strange situation now so you won't have to be wishing you had planned for it when it actually happens.

Rocky & Sheri Rhoades
'01 Volvo 770
2016 DRV Mobile Suites, Houston
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Going to ECR this year one exit from a truck stop was a steep hill down to the roadway, I am sure the trailer got a lot closer to my cab than I care for. Of course this trip was just with our one ton and not a HDT.

Chris  :ph34r:.

 

Sandpiper 379 FLOK, Volvo 2012 730.

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2 hours ago, rickeieio said:

Do yourself a favor and take a measurement with the rig at 45 degrees.  You might be in for a surprise.  It's all been discussed here in the past year.

I give up.  I've been trying to find the drawing Henry posted showing the arc of the front cap of a fiver during a turn.  Some times the closest point isn't at 90 degrees.

KW T-680, POPEMOBILE
Newmar X-Aire, VATICAN
Lots of old motorcycles, Moto Guzzi Griso and Spyder F3 currently in the front row
Young enough to play in the dirt as a retired farmer.
contact me at rickeieio@yahoo.com

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I believe closes would be at 45 degrees (front corner of trailer to center of truck), then after 90 degrees it would get close to the side of the trailer.
I also would think it would have to do with your pin box.  One straight down would give you less room.

"It is better to have more truck than you need than to need more truck than you have"

2001 Volvo 660, Cummins 400 ISX, Eaton 3 Peddle Auto Shift    
2014 Fuzion 40' Toyhauler
2015 Smart Car                                                                                                                                                                          

                                                                                                            

 

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Glenn and HeroMaker, that is my thinking.  1/2 width of trailer (me 48") + safety  margin makes sense to me.

What do people use for the safety margin?  NoDIrectionHome uses 10".  I was thinking less. 

Here is how my extended pin box would swing.  I'll confirm this out in the desert this weekend.   It extends the pin to the front edge of the 5th wheel (and the 5er has a bit of curvature, not the box shown below),  So, it appears the closest point of approach is 90 degrees.  Up until 70 degrees there is a BIG margin.

How many people have had to jack-knife their rigs?

5ad9868eadcbc_Trailerarc.png.447aa441632866ba7675435ac89a45b6.png

  

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2010 Freightliner, DD15 Eaton Ultrashift, 2015 New Horizons 5th Wheel.

Occupants - Dena/Brad/Hershey    BLOG LINK

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We use about 151" from back of cab to pin location. That leaves 18" for drom (16" drom and 2" to BOC).  That is more than enough, and accounts for different types of pinboxes and caps. 

Jack & Danielle Mayer #60376 Lifetime Member
Living on the road since 2000

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It’s the long side of a right angle triangle unless the king pin is right in line with the front of every trailer you will ever hook up to, then it is 1/2 the trailer width.  Take a stick and saw it off at the distance from the center of the king pin to the widest point at the front of the trailer plus 6”.  Then use the stick as a story stick as you look at the layout you want at the back of the truck. Now from the end of your stick look up at 90 degrees. That line needs a minimum of 8” of dip clearance to anything on the deck of the truck. 

"Are we there yet?" asked no motorcycle rider, ever. 

 

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Jack - thanks, that 151" number is helpful!  I've got that to play with.

NotEVen - I like your stick concept.  Basically did that out in the desert this weekend by jackknifing the truck and then plotting the arc of the longest leg of that triangle you reference at 5 degree intervals.  With the extended pin box nothing crossed a line 48" from the pin box until I hit 90 degrees, so that's encouraging.

I'm thinking this is all going to come together and I'll be able to squeeze a drom and the Smart on the deck and have a safety margin for those tight turns over a dip in the road.

 

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2010 Freightliner, DD15 Eaton Ultrashift, 2015 New Horizons 5th Wheel.

Occupants - Dena/Brad/Hershey    BLOG LINK

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Brad - yer Freightliner should not be able to "out turn" the trailer in your signature image in "go forward".  It is amazing how fast your rig folds in half when you are wiggling backwards into some spot with 3 people waving their arms and hollering at you which way to "turn yer wheels" 

"Are we there yet?" asked no motorcycle rider, ever. 

 

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NotEven and HEROMaker - both great points.  I agree "going fwd" shouldn't ever be a problem.  I would anticipate anytime I'm trying to get into a tight spot and all the onlookers giving direction I would have already unloaded the Smart car...then no clearance problems.

Not looking to upgrade trailers anytime soon but that's definitely a good point.

E-mailed comfort ride hitch and asked them if I could move the hitch back and secure it with only 6 bolts instead of the current 8 on each side.  That would give me an extra 7 inches too.

2094790416_NewHorizonsmall.jpg.b597b886c0fa2457938fb2cfe3e6cd0b.jpg

2010 Freightliner, DD15 Eaton Ultrashift, 2015 New Horizons 5th Wheel.

Occupants - Dena/Brad/Hershey    BLOG LINK

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I have 150" from the back of the cab to the center of the hitch head. I have no drom so I have lots of room.

 

Brad

Brad and Jacolyn
Tucker the Wonder dog and Brynn the Norfolk Terrier
2009 Smart "Joy"
2004 VNL630 "Vonda the Volvo"
2008 Hitch Hiker 35 CK Champagne Edition
VED12 465 HP, Freedomline, 3.73 ratio, WB 218"
Fulltiming and loving it.

 

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