Re: Rear Bumper

[Tom Mandera <tsm1@domain.elided>]

Steven Stegmann wrote:
> 1- Cut a 4x6 inch piece of 3/16 wall steel tubing to the desired width.
> Cap both ends with a slab of 3/16 plate.  6 in is the vertical side.

Why 4x6 and not something smaller?  I have some 2x6x3/16wall that I'm
using for my front bumper, and I thought I might use something similar
in the rear.. just seems like you're adding weight... OTOH, you're using
the 4x4 spacers to get the bumper back anyhow..

Here's a thought I had on the ends:  How about capping them a little
"narrow", and then taking a section of 4"diam 3/16" wall steel tube and
cutting it down the middle, making two long semi-circles.. then weld
THOSE on *over* the "flat strap" cap.  This would give something of a
rounded edge.  You could also cap the bottom of this semi-circle and
drill for a drain, and then use it to carry shovels or something.

I mention this after I drug a friend off a snow bank last Saturday..
kids were crashing snowbanks in the highschool parking lot in a Ford
Espire (not that I would've EVER done anything like that when I was
younger) and got high-centered.  After I drug the car off, it didn't
stop immediately, but turned.. I stopped, the car made a 90 deg turn,
but still managed to gently bounce off the "good" corner of my factory
step bumper.. I think, had it been squared off, it might've left a mark
on the Espire.

> 3- Cut a hole straight through from front to back for a class III
> Oh yeah put the hitch in the middle of the bumper.  The bottom of the
> reciever lays on the bottom of the 4x6 tube.  The hole is right near the
> bottom of the 4x6 tube.

This seems the strongest way of doing it, but I'm concerned about the
Scout's already poor departure angle.. mounting the hitch tube at the
lowest point in the bumper will make the hitch poke out a little bit,
leaving it the limiting factor in departure angle.. 

How about mounting the hitch a little higher up?

Also.. how far does the hitch have to stick out to allow you to get the
hitch pin in?  I was thinking it might need to be out a bit.. and then
"ring" the hitch tube just behind the hitch pin and then weld that
assembly to the box tube.

> 5- Cut two 12 in lengths of 1/2" diameter cold rolled and bend into U
> shapes.  Weld these to the bottom of the 4x6 and the reciever tube.
> Weld anywhere they touch anything.  These are for the safety chains.

Why on the bottom?  Would it be OK to mount the safety chain attachments
to the top of the bumper?  Again, the idea is to minimize what's going
to get ripped off.

How about re-using old U-bolts for this task?  Or new U-bolts.  The
trick then becomes affixing the U-bolts to the top of the bumper in such
a manner that it won't interfere with the tailgate.. don't want to lower
the bumper to allow the tailgate to come down.. that defeats the purpose
of moving the safety chain mounts up!

Might be better off just welding some small U-bolts (or U-bolt like) or
D-shackles to the rear "face" of the bumper.. then you don't sacrifice
departure angle for safety chain hooks.

> 6- Cut two 24 in lengths of 3x3x1/4 angle iron.  Position these to run
> forward under the frame and cut two holes each to match the provided
> holes in the Scout frame for the class III trailer hitch.  These stick

FWIW, my factory step bumper uses the same holes.  There's angle-stock
that's bolted to the frame, and then the bumper bolts to the sides
(vertical) of the angle stock.

> need to be notched to fit over the 4x6 tube.  I had to add 3/16 flat
> shims to take up the space between the bottom of the 4x4 spacers and the

Where did you position the 4x4 spacers then?  If you were doing it
again, would you just position the 4x4 spacers with the bottom of the
frame to keep 'em flush?  Or maybe use 5x4 tube?

> Oh yeah.  The 3/8 bolts that are between the main frame rails and behind
> the gas tank have to be welded to the frame (before you install the gas
> tank) because there is no way to get a wrench anywhere near them to
> tighten the bumper spacer bolts.

What about those "stars" I see on some factory screws (like the hardtop
ones) to keep 'em from spinning?  Could you simply use something like
that on the bolts fed through from the gas tank area?

or optionally weld the head of the bolt to a piece of strap.. so that
when you tighten it, the strap would get wedged against the "C" channel
on the rear of the frame and thus keep it from turning.. but not require
dropping the tank and welding the bolts in?

(I know welding the bolts is the "right" way of doing it.. but I'm NOT
dropping the tank until I have 33gal to replace it with.)

> So, the angle irons take the pulling load of the trailer.  The spacers

Does the angle run all the way to the rear face of the 4x6 tube? 
Sacrificing departure angle again.. did you then grind the corners of
the angle down at an angle to regain some of the departure angle you've
lost?

> welded into one solid piece and weighs 110 lbs,  I think this assembly
> probably really stiffens the back end of the frame.

I guess I should wait 'till I switch to my rear spring over.. ;-)

> Any comments?  Make sense?

Sure does make some sense.  

> On the someday list for the bumper is:  Air fittings, Spare tire gate,
> Towing eyes.

Tow-hooks could be incorporated like Bill Thebert did for the front -
cut some 3x3 box tube at a 45 deg angle and weld to the rear face of the
bumper, then bolt tow hooks to it.

Another idea borrowed from Bill - drill a pair of 1/2" holes near either
bumper end, and leave just the heads of a pair of bolts through the
bottom side.. to keep your Hi-Lift from walking side to side.

Is your bumper wide enough to stand on safely?  Maybe add some diamond
plate steel to the top to bring it back a little bit (particularly if I
use 6x2 or 6x3) to make a decent step (important after you lift your
Scout!).

Those 4x4 "spacers" sound like a nice spot to store some stuff.  I
wonder how to go about putting a hinged door or something on it...

Maybe a couple of lights need to be mounted in the area around those 4x4
spacers, too.. for shining light down around the back of the Scout for
late-night rock-crawling.. ;-)  Or.. with enough lift, they'd make great
reading lamps, too!

Be sure to mount the air fittings between the bumper and the frame if
you can.. keep 'em out of harm's way.  

-Tom Mandera, Helena MT
http://www.tmcom.com/~tsm1/scout