I didn't get to work on the rig on Saturday, but
Sunday was a very productive day. With the help of my friend Scott, we
were able to knock out all the tubes in the upper structure that had a bend in
I have learned a few helpful things about bending
tube this go around and would like to pass them along. These tips involving
"fixing" a tube that you may have over bent or slightly under bent, being just a
degree off can really throw the design off if the tube is a long one. The
first thing to keep in mind is that you will never get all your angles perfect.
The first few tubes I bent on my old rig were very frustrating because I was
going for perfect angles. Once I accepted the fact that they would rarely
be right on, things were much easier and less stressful. One of the big
reasons it is hard to nail the angles is that the steel tubing has a certain
amount of spring back. This means you have to actually over bend it to get
to the angle you want. The amount of over bend required varies and goes up the
tighter the bend. This means a 15 degree bend may only require you to go 3
degrees past your target bend angle while a 95 degree bend could require you to
go 10 degrees past your target angle to achieve the desired bend.
The material thickness also affects how much spring back the tubing will have.
What this all means is you will be able to get within +/- a degree of the
desired angle pretty easily. this may cause the tube to not fit where it
is supposed to, here's the solutions:
If you haven't bent it far enough you have two
options. The first and easiest is to put it back in the bender. The
second option is to use a ratchet strap to pull the tube inward (shape
permitting). The ratchet strap option is really useful when trying to get
a hoop to line up on both ends with an existing structure.
If you have over bent the tube you need to unbend
it. You will need a place to wedge one end of the tube that is anchored
solid. A receiver hitch on your tow rig, the stake pockets on a trailer
or even the rim of a derelict parts car work well. You then stick one end of the tube into the anchor, slide a
6-12" long piece of sleeve tubing into tube to be bent leaving half of it
sticking out the end. Next, slide another, longer tube over the exposed end of
the sleeve tube. Now your are ready to unbend. Grab your lever and
pull in the direction you need to open up the angle. Keep in mind you
will have to bend past where you want as the tube will spring back after your
pull. I usually just give it a couple big pulls and then take it back to
the buggy to check the fit, repeat as needed.
Next up is some cross bracing.
One of my goals in this project was to
keep the money pit under control. So far so good. To date I have
sold approximately $5,600 worth of parts off of my old rig and the parts
truck with another $2,100 in
parts to go.
As you can see in the picture above, my
expenditures have totaled approximately $5,400 (taxes and shipping included) at this point and my to be
purchased list is rapidly shrinking. $680 of that total was for tools and
consumables used in the buildup, the tubing for the project ran $987, and the
misc. steel and various brackets have come to $147 so far. I did manage to get a
bunch of large steel plates free with the tubing purchase so the material cost
could have been higher. You will notice some of the prices I paid were very
good, this was made possible by several group buys with the BTG Rockcrawlers.
I guess it was just good timing on my part or luck that several of us started
major build ups at the same time. The parts without a price I am
considering free because I pulled them from my parts truck and managed to make
the purchase price of the truck by selling the remaining parts. The total
would be close to a $1000 higher if I would have had to purchase those
I am also tracking my time. To date
I have 113 hours into the design, 125 into the build, and 46 hours of tear down
time (parts truck and old rig). The design time is kind of high due to me
going back in and trying all sorts of different configurations, one of the
advantages of modeling the buggy before building it.
Some of the tabs I have been working on
(lower section of the picture). The shiny stuff in the upper section were
all bare steel parts now nickel plated (hydro cylinder mounts, shifter cover,
steering arms and misalignment washers).
I ordered a bunch of electrical parts
Del City for
the main wiring harness and they arrived today. The plan is to clean up the main
wiring harness and make it look really nice. I bought some shrink tubing, some
colored wire wrap, new relays w/ wire harnesses, a power distribution block and
some fuse blocks. Unfortunately the blade style circuit breakers I bought
don't fit in the fuse boxes (too tall).
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