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n2jeepn.com's official
project Jeep 
gets a rear bumper
I’ve wanted a rear bumper with tow
points for my CJ-7 forever. I could never justify spending the
money for one knowing that I could build one for much cheaper
and customize it exactly how I wanted it. I finally decided to
buy a MIG welder and start the project.
I looked at many designs on the web and
in catalogs and incorporated all the parts I liked into a
design of my own. I chose to concentrate on just the bumper
itself to start with and will design and build the swing out
tire carrier later.
Here is the basic design of the bumper:
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| Click on image for larger
view |
The main body of the bumper is made from
3/16” wall, 2”x4” rectangular tubing. It is 60” long,
which is about the width of the CJ-7 body tub. The D-ring
hangers are made from 3/4” thick 3” steel bar stock. The
D-ring hangers go completely through the bumper and attach to
the mounting plate in the rear. I went with this design since
they will be welded in 3 separate spots, the front & rear
of the bumper and the mounting plate, therefore reducing the
likelihood of failure from breaking loose. I also decided to
have the bumper mounted a couple inches out from the rear
crossmember so there was a little more depth for accessories
when I add the swing out tire carrier. Although it will get
little use, I also decided to add a receiver hitch tube. It is
mounted up inside the bumper, rather than underneath, so it
does not hinder the departure angle.
If I’ve learned anything from other people’s
projects and my own, for that matter, it is measure twice
before cutting. So, I decided I’d measure three times before
cutting. This extra effort paid off since everything fit
together perfectly when it was time to assemble the bumper.
Having the right tools for the job is essential to having a
successful end result as well. I started the project doing all
of the metal cutting with a 4” angle grinder with a cut-off
wheel. It quickly became apparent that it would be well worth
the investment to buy a 14” abrasive cut-off saw. I found
one on sale for a very reasonable price and it made all of my
cuts much easier and more importantly they were square.
The
most challenging part of creating the bumper was cutting the
holes for the receiver hitch tube and the two
3/4"x3" pieces that would go through the bumper and
function as the D-ring hangers.
I ended up drilling the corners of each square hole with a
1/2" drill bit and then connecting the drilled holes with
an angle grinder fitted with a cut-off disc and a jigsaw
with a metal cutting blade.
Once
the holes in the bumper were cut out, then it was time to line
up the pieces and weld it together. This was a bit of a
challenge too since having everything line up square is
critical to make sure the bumper mounts firmly to the rear
crossmember. Again. I used the "measure three times"
rule before welding. It's handy to have a square or angle
finder tool around to confirm that everything is fitting
together properly.
*
* I just finished the tire carrier to go with the bumper. See
it HERE.
Here
are some pictures of the construction of the bumper: [Click
pictures for larger view]
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Welding the 2" receiver hitch tube
on. The receiver tubing goes all the way through the
bumper and is welded on the front and back for
additional strength. |
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Here is the receiver hitch tube with a
reinforcement ring welded on the end and the safety
chain hangers attached. |
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Here I have one of the 3/4"x3" pieces
welded on that will support the mounting plate. The hole
to the right of it is where the other 3/4"x3"
bar will go through the bumper and act as the other support
for the mounting plate and the D-ring shackle hanger. |
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Here is the completed mounting plate and
the d-ring shackle holder welded on and shaped. |
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In this view the ends of the bumper have
been cut off at an angle and some thick sheet metal
welded on to cap the ends. |
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Painted and ready to put on. |
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This is a shot of the brackets I made to
tie the bumper into the frame. The rear crossmember is
not strong enough by itself to properly support a bumper
during towing or extraction. These brackets are made
from 1/4" thick angle iron. |
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This is how the bumper attaches to the
rear crossmember. Each side has 4 1/2" grade 8
bolts holding it on with the frame tie in brackets
pictured above on the outermost bolts. |
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The finished product. |
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Another view of the finished
product. |
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