1 Year Update
Now that Project BMP is a year
old I figured it was a good time for an update. Right off the top the
chassis is in great shape. I have a few small dings here and there but
no cracks so far. The only visibly deformed tube is one of the diagonal
windshield braces (1.00 x .120 wall) but I can't remember ever hitting it.
As you can see the aluminum
skid plate is holding up well to the abuse. You may recall the UHMW
(plastic) skid plate I initially installed only lasted a few runs before caving
in. I also checked all the links for straightness and so far so good.
The decision to sleeve the lowers and brace them with a rib along the top looks
to have been a good one.
The link mount cross members
also looked to be in good shape with no visible bowing or cracks. This was
one item that concerned me after seeing all the carnage over MLK weekend but it
appears that my bracing method has allowed the .120 wall cross member tubing to
take the loads I have placed upon it. I did discover the bolts that held
the transfer case mount to the transfer case had come loose causing the transfer
case to weep oil.
My beadlock rings haven't been
taking the abuse so well. This is a picture of one of the front rings off
of my Trailready beadlocks. I had ordered their slim rings because I liked
the way they looked but now feel these are too thin. I was also having
problems with constantly loosing retaining bolts and feel the ring was part of
the problem since it was distorting so easily. I have since replaced all the
supplied nuts with nylock nuts in the hope that if the ring gets tweaked any
more the nuts won't be able to back off. Steel is definitely a better
material in this application.
The motor mounts need a
re-design. I should have put the rubber bushing at the motor end of the
mount and triangulated the tubing off of the chassis. The existing setup allows
a for a lot of movement which has caused the plates at the end of the mounts to
start bowing. Looking at the motor in the engine bay also reveals a slight
list to the drive train.
The plate I welded to the lower
steering arm has continued to be a problem. Luckily when the area around
the welds lets go, the upper steering arm is beefy enough to take the loads and
I have been able to make it back to the trailer. I also bent the front
axle cross member after a good rock hit which caused some of the welds on my ram
mounting blocks to break. I am still working on a re-design for this area.
Update 2-12-06 - I increased
the thickness of the cylinder mounting plate and fabricated a plate that ties
the upper link mount tube to the cylinder mount plate. To make the
cylinder removable I had to make this assembly bolt on.
On the steering arms I cut the
top off of a 4" long piece of rectangular steel tubing and wrapped it around the
bottom of the knuckle to create a tight fit. Next trimmed the leading edge
down so I was left with a single flap of steel which was hammered around the
front of the knuckle and welded to itself on the other side of the knuckle. Next
I welded the steering arm brace to this new lower bucket. Now the force of
the steering should be working the U-shaped brace instead of the welds.
I got this idea after seeing a variation of it used on another club members rig.
The rear mounted winch was a
short lived experiment. When it was working I found is useful to suck down
the back end in off camber situations. Unfortunately the winch motor
appears to have burned out after I stalled it once. I need to confirm this
by pulling the unit apart but for now I removed it from the rig.
One thing I have found lacking
after a year is power. To be fair when I built the rig we weren't
attempting obstacles with the level of difficulty that the current obstacles
have provided, we definitely ratcheted up the difficulty a notch in the last
year by driving stuff that in the past we would have winched. So far power
level has been just enough if everything was working 100% and I didn't have too
much weight on board but I have noticed rigs with slightly more power having an
easier time on some of the vertical obstacles. So, a new power plant may be
on tap if I can locate one for the right price. The current front runner
is a Toyota 2.7l for it's small size and impressive power output but I would
also consider a Suzuki 2.0l.
I am still happy with my choice
in tires. The 42" Irok's provide great traction and have proven fairly
reliable. I did slit one a few months back but so far my homegrown patch
job has held (I left the tire plugs in and applied a tire patch to the inside of
the tire. The cut was about 3-4" long in the middle of the sidewall.