Jump to content

calling all welders! Truck bed question.


PEIFamily

Recommended Posts

Just started laying the steel on my truck bed (14' long) and the frame is using 2x2 rails on the existing truck frame, then 3" channel iron crossways every 16". (all 1/4" steel) I am using 3/16" checkered plate steel for the truck platform. I laid the first sheet down, clamped and welded around the 3 sides, then plan to lay the other sheets. One of my workers was saying I need to flip the bed upside down to weld along each channel iron to make it strong. I understand it would be better to do that in a perfect world, but is it really needed?

 

The bed will weigh about 2000lbs or so when I finish laying the sheets down so I don't want to have to flip it if I don't need to..

 

My weld lines would be like this:

 

The red is what would have a solid bead of weld all the way around it.

 

 

So my question is, do I need to flip it and run a bead along each 16" channel iron as well or can all the welding be done from the top and not weld the center of the sheet plates to each crossbeam? I used about 12lbs of rods already on just the framing so she is welded pretty strong.

2006 Volvo 670 singled long

2011 Heartland Sundance 3300CK

2006 Smart passion

2001 F350 DRW CREWCAB

Link to comment
Share on other sites

Personally, I would flip it and weld your cross pieces to the sheets. You do not need to lay a continuous bead, stitch welds will be fine for your application.

 

Towing the steel sheets into your cross pieces will give a lot of added strength.

John

Southern Nevada

2008 Volvo 780, D13, I-Shift

2017 Keystone Fuzion 420 Toyhauler 

2017 Can-Am Maverick X3-RS

 

ALAKAZARCACODEFLGAHIIDILINIAKSKYLAMAMNMS
event.png

 

Link to comment
Share on other sites

You should weld underneath, stitch welds are imperative, that stuff will curl up like a potato chip. You really want to undercoat the bottom after you weld it.

 

Steve

2005 Peterbilt 387-112 Baby Cat 9 speed U-shift

1996/2016 remod Teton Royal Atlanta

1996 Kentucky 48 single drop stacker garage project

 catdiesellogo.jpg.e96e571c41096ef39b447f78b9c2027c.jpg Pulls like a train, sounds like a plane....faster than a Cheetah sniffin cocaine.   

 

Link to comment
Share on other sites

For what it's worth, my bed surface will be bolted to my cross members.

 

Benefits:

  • Easily removable for servicing the truck
  • No need to weld under truck, upside down
  • Panels can easily be dropped off at paint shop or Line-X shop
  • No welds to crack years down the road.

Stainless steel flat head socket cap screws will hold the plate down.

"Willy Mammoth" - Volvo 730, Sold

Heartland Cyclone 4000 Toy Hauler
T-Minus 26 years and counting to being a full timer.

Link to comment
Share on other sites

For what it's worth, my bed surface will be bolted to my cross members.

 

Benefits:

 

  • Easily removable for servicing the truck
  • No need to weld under truck, upside down
  • Panels can easily be dropped off at paint shop or Line-X shop
  • No welds to crack years down the road.
Stainless steel flat head socket cap screws will hold the plate down.

That is definitely an option if you want to be able to remove your panels. With an air ride truck I would be surprised to see cracked welds down the road.

John

Southern Nevada

2008 Volvo 780, D13, I-Shift

2017 Keystone Fuzion 420 Toyhauler 

2017 Can-Am Maverick X3-RS

 

ALAKAZARCACODEFLGAHIIDILINIAKSKYLAMAMNMS
event.png

 

Link to comment
Share on other sites

Similar to BMZero, we bolted our top plate down. We welded l angles to the frame work and to the underside of the deck plates and then ran St/St bolts through both angles to hold deck, plus our drings hold deck in place also.

Dave

2005 Freightliner Century S/T, Singled, Air ride ET Jr. hitch
2019 46'+ Dune Sport Man Cave custom 5th wheel toy hauler
Owner of the 1978 Custom Van "Star Dreamer" which might be seen at a local car show near you!

 

Check out http://www.hhrvresource.com/

for much more info on HDT's.

Link to comment
Share on other sites

For what it's worth, my bed surface will be bolted to my cross members.

 

Benefits:

 

  • Easily removable for servicing the truck
  • No need to weld under truck, upside down
  • Panels can easily be dropped off at paint shop or Line-X shop
  • No welds to crack years down the road.
Stainless steel flat head socket cap screws will hold the plate down.
My two center panels are bolted just like that. Really makes it easier to get to vital components. I put some copper anti seize on the screws but have found I need to periodically tighten them.

2006 Volvo 780 "Hoss" Volvo D12, 465hp, 1650 ft/lbs tq., ultrashift

Bed Build by "JW Morgan's Custom Welding"

2017 DRV 39DBRS3

2013 Smart Passion Coupe "Itty Bitty"

 

"Don't go around saying the world owes you a living. The world owes you nothing. It was here first!"

Link to comment
Share on other sites

Thanks everyone!

 

I was going to create a few access holes (center where the manifolds are) and at the front of the ET hitch to access the leveler and airbags if needed. (I know if I don't put an access hole there, I will blow my leveler a day after the bed is installed ;)

 

I was thinking about just cutting the holes out and welding hinges on there, let the weight of the 3/16 plate hold them down. (hinges towards the front though :D ) But bolting may be a better option?

 

I considered myself an amateur welder, but definitely feel a lot more confident in my welding now after this far along :P

2006 Volvo 670 singled long

2011 Heartland Sundance 3300CK

2006 Smart passion

2001 F350 DRW CREWCAB

Link to comment
Share on other sites

PEIF,

 

I am attaching a pic of my panels which you can see in the center with the screws. They extend the length of the bed and trust me when I say I was glad they did on more than one occasion. Not saying this is the best way but be sure your access panels are adequate to get at most things between the frame. Good luck and looking forward to following your build.

2006 Volvo 780 "Hoss" Volvo D12, 465hp, 1650 ft/lbs tq., ultrashift

Bed Build by "JW Morgan's Custom Welding"

2017 DRV 39DBRS3

2013 Smart Passion Coupe "Itty Bitty"

 

"Don't go around saying the world owes you a living. The world owes you nothing. It was here first!"

Link to comment
Share on other sites

PEIF,

I am attaching a pic of my panels which you can see in the center with the screws. They extend the length of the bed and trust me when I say I was glad they did on more than one occasion. Not saying this is the best way but be sure your access panels are adequate to get at most things between the frame. Good luck and looking forward to following your build.

That is how I am designing my bed, with the outer panels welded in place. Though I am also designing the bed to be a quick change out. I made a 22' foot quick change for a KW K-100 and it worked very well, pulling a 40' Flatbed.

John

Southern Nevada

2008 Volvo 780, D13, I-Shift

2017 Keystone Fuzion 420 Toyhauler 

2017 Can-Am Maverick X3-RS

 

ALAKAZARCACODEFLGAHIIDILINIAKSKYLAMAMNMS
event.png

 

Link to comment
Share on other sites

Yeah the forum changed formats couple of years ago and a lot of posts and pics were lost.

2006 Volvo 780 "Hoss" Volvo D12, 465hp, 1650 ft/lbs tq., ultrashift

Bed Build by "JW Morgan's Custom Welding"

2017 DRV 39DBRS3

2013 Smart Passion Coupe "Itty Bitty"

 

"Don't go around saying the world owes you a living. The world owes you nothing. It was here first!"

Link to comment
Share on other sites

That is definitely an option if you want to be able to remove your panels. With an air ride truck I would be surprised to see cracked welds down the road.

I've seen several beds from that bed builder in Poolville with cracks.

MY PEOPLE SKILLS ARE JUST FINE.
~It's my tolerance to idiots that needs work.~

2005 Volvo 780 VED12 465hp / Freedomline transmission
singled mid position / Bed by Larry Herrin
2018 customed Mobile Suites 40KSSB3 

2014 smart Fortwo

 

 
 
Link to comment
Share on other sites

My center section is 3/16 aluminum bolted down.

The rest of the deck is 3/16 steel. What I did different is on the steel deck

Panels I plasma cut 1/2 x4 inch slots in the deck and plug or rosette welded

The deck to my deck frame. I also had plenty of room to stitch weld it underneath while on the truck.

 

I think it came out real clean and smooth.

Link to comment
Share on other sites

How are attaching the rails to the original truck frame? Mine is bolted through the sides of the frame rails. Just something I thought of when you said they were 2 X 2. The frame rail is wider than that so you will have to slide the rails out so they align with the otter edge of the truck frame. And of course you already knew to unhook the battery before welding so I won't mention it.

As for the welding the underside. Overhead welding is not that hard. You are only going to stitch weld not a continuous bead and it does not have to be pretty because no one is going to see it anyway. I'm guessing there is room to get underneath and work. That would be much easier than flipping it over if it weighs 2000.

Or if you have a way to flip it how about building it upside down and then flipping it onto the truck. All of this is just my opinion so take what you can use and leave the rest.

 

Where are you located and doing the construction?

 

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.

 

Link to comment
Share on other sites

There's kind of what I would call a "ratio" of sorts that must be considered when choosing welding over bolting. If your framework is heavy and can not flex, then bolting would be a great option. But if the framework is lighter and can flex, then welding will help strengthen it and tie the top into the framework.

 

But welding does pull and warp steel like mad. This can potato chip the whole thing. Also if the bed design is light weight, you need to take into consideration where the tie downs are located as a small load and improper tie down locations can cause all kinds of issues, whether bolted or welded.

 

If you have any doubt at all in your abilities to weld over head, then yes, flip it. But the position of the weld is not the limiting factor for strength. The operator and welder settings are.

I'm a work'n on it.

Link to comment
Share on other sites

 

For what it's worth, my bed surface will be bolted to my cross members.

I highly recommend NOT using stainless hardware. The bolts are much lower strength and are notorious for fretting (welding) of the threads even before being fully tight. CRES, also known as corrosion resistant hardware is a much better choice. If you insist on stainless, liberal use of anti-seize is recommended.

BTW I also do much endorse bolting vs welding for many of the reasons sited by others

"There are No Experts, Do the Math!"

2014 Freightliner Cascadia DD16 600hp  1850ft-lb  18spd  3.31  260"wb
SpaceCraft S-470
SKP #131740

Link to comment
Share on other sites

Fastening the beams to the deck will make the whole construction stiffer, less bendable.

 

If you are going to weld the beams to the deck, your options are:

 

Flip the deck and Stitch weld 3" every 12" or so, alternating sides of the stiffener

 

Weld from the bottom- i would rent a wire feed machine for this, lots less slag falling on you

 

Cut slotted holes in the deck on top of the beams and weld from the top- maybe a little tricky if youre not good with a torch

 

But i would not bother, if the deck is stiff enough now. Are you going to be parking a f350 on it? The plates will not fall off, and if you see a crack, it will be right in front of you.

 

More heat input will cause more distortion and waviness in the deck.

98 379 with 12.7 DD

LG Dodge w/5.9 CTD

Chrome habit I’m trying to kick.

Link to comment
Share on other sites

You might consider building the deck in sections, then bolting the sections together. Lighter individual sections, easier to flip, flex will occur at the bolted joints, less warpage, etc, etc.

 

My deck is solid in front, just big enough for a smart. Then the fenders are each one piece, with another sheet bolted between. However, I failed to follow my own advice and welded the rear wrap into the fenders. But I can remove 14 bolts, and make one small cut with the plasma, and the whole thing comes off with the fork lift as 4 pieces.

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 rickeieio1@comcast.net

Link to comment
Share on other sites

Lots of great ideas here. Thanks for all your feedback. These posts will help out others down the road as well.

 

I have mine built as one... Should have built as two due to the weight lol

 

Even though the bed is welded solid as one piece, I will be bolting it to the frame of the truck. On the side of the 2x2 rails that sat on top of the frame, I welded a 3" channel and had a hole drilled to match up with an existing frame hole. There are 6 of these. And where the 5th wheel hitch was, I have channel iron laying down with holes drilled to fit the original holes.

 

So each side will have 5-6 very solid mounting plates and 3/4" grade 8 bolts. That should be enough?

 

There will be a smart car loaded on with the smart car ramps.

 

I think my best bet would be to lower one side from the stands I am using and lift the other side up to a 90 degree angle and weld the bottom that way. It would be easier to lay back down afterwards to then get it lifted up and placed on the bed.

 

I estimate I will be using about 20-25lbs of rods by the time I finish.

2006 Volvo 670 singled long

2011 Heartland Sundance 3300CK

2006 Smart passion

2001 F350 DRW CREWCAB

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

RVers Online University

campgroundviews.com

RV Destinations

Find out more or sign up for Escapees RV'ers Bootcamp.

Advertise your product or service here.

The Rvers- Now Streaming

RVTravel.com Logo



×
×
  • Create New...