Finishing Touches on the Scale YJ

Building this little scale project Jeep YJ has turned out to be even more fun than previously thought.  Each little piece that was made, started to make the rig look even better and more function, as well as capable in rocks.  In the last installment, I really wanted to start focusing the build on how the Jeep could handle the roughest of terrain.  Now that it is finished, I realize that competition ability is not out of the question but this pint sized rig will doubtfully ever win a major rc rock crawling event.

Without the aid and products from David Diaz of Diaz Designs www.diazdesigns.net , this Jeep would have never materialized, well, not nearly as well as it did.  The leaf springs are, without doubt, the biggest weak link in a leaf designed scale crawler.  The metal Juggernaut springs are not an option at all if you want any flex (Picture 1).  The Diaz leaf springs are the way to go and no one else makes quality polycarbonate springs or any type of plastic spring, for that matter.  The springs flexed very well, however, there was a limiting factor; the shackles.  The shackles that I was using proved to be too short.  As the long plastic spring compressed, it became much too long for its current mounting points… so a longer shackle was needed.  Diaz came up with, yet again, polycarbonate spring shackles that were long enough to accommodate his springs.  I wanted to take his idea one step further and I looked to Currie Enterprises.  Their Boomerang shackles (Picture 2) were the ticket and all I had to do was make a scaled down version to allow the rear springs get longer.  The Boomerang style shackle also lets the rear pivot point track under the rear bumper on full compression!  Up front, a new pivot mounting hole was drilled through the frame. 

Great!  The suspension was flexing like mad (picture 3) and my only concern was that the plastic springs, in their extreme negative arch during up travel, would snap.  To date, with much hard testing and wheeling, none of the springs have shown any cracking or breakage.  All four springs have settled and have lost some of their static ride height arch, which is a welcome change anyway, especially with the longer shackles.
After more testing, I quickly realized, like on many 1:1 Jeeps, that the suspension up and down travel was being limited by shock travel.  The biggest problem lies in the selection of dampers that us radio control guys have to choose from.  The TLT shocks are nice (Picture 4), fairly long and look good if polished or the diameter turned down, however, they still measured too short to provide all the travel that the plastic springs could afford.  It was time to put on the rc thinking cap and make my own long travel shocks.  It wasn’t soon after I put that cap on that I had some aluminum tubing, tlt plastic spacers and rod ends, some metal rod that was threaded at each end, with the appropriate length, and some fuel tubing. 

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After painting the parts white, for that authentic damper look, I pieced together each shock, using the spacers and rod ends as end caps to the shock body tube and the fuel tubing as the shock piston.  The fuel tubing slides in and out through the shock body tube with enough friction to act as perfect dampening.  I slapped a Rancho Suspension sticker on each of them and believe they are the best working and looking shocks I’ve seen in rc rock crawling (Picture 5).  Best of all, the shocks are all long enough now, allowing huge travel.  The fronts required a taller shock tower to be extended off of the frame, as the rears stayed in their triangulated position.

The suspension was done.  I really can’t see how to improve it anymore, without negatively affecting the rig’s overall stability (Picture 6).
I wanted to have a tire choice with this project.  One set, the Proline Racing 2.2 Moabs are perfect for sandstone and slick rock, with their super sticky M2 Rubber Compound.  The Diaz Designs Bead Lock Rock Rings give it that hardcore look!  The second set of rubber came from IMEX RC.  The 2.2 Swamp Dog Tires (Picture 7) look almost identical to an Interco Swamper Bogger and they perform in the mud and sand just as their larger counterparts do.  The black rock rings shown are from Montana Scale Designs and are only one of many products that Ben designs and sells himself.

Going back to the aesthetics department, I figured that this Jeep was deserving of a look-a-like Currie Enterprises Tire Carrier and rear bumper.  S&S Plastics of Denver stepped up and provided the solid pieces of Delrin to make the rear pieces.  A lot of planning, measuring and sanding took place to get the end result (Picture 8).  A high clearance rear bumper combined with a spare tire carrier that is totally function, down to its swing out characteristics, to the large “spin on, spin off” design, was produced!  A little flat black from the rattle can was in order for the entire rear parts, including the chassis.  The whole rig was stripped down to the aluminum chassis and was covered in black.

The major components for the Jeeps looks and performance were just about finished but I wanted a few small parts that would separate this rig from others, as well as give it that complete scale look.  No self respecting Jeeper hits the trail without their trusty HiLift Jack and this one was no exception.  With some creativity, some spare plastic and a small length of carbon fiber rod for the handle was put together to make my HiLift (Picture 9).  After seeing how good the carbon fiber looked as a Jack handle, I convinced myself to fab up a small shovel for the front of the Jeep.  A little more Lexan for the shovel spade, a dab of red and black paint and the shovel was mounted up front to the stinger.  A couple of windshield mounted lights, whip antenna and my hand made winch roller fairlead really started to set this Jeep off, making it look as if you could climb inside and turn the key (Picture 10).

The look of this rig was nearly complete.  During a scale run at Finish Line RC in Denver, CO, Brad Dumont, from Bender Customs recommended some rocker panel rock rails be installed on the Jeep.  He showed me how well his rock rails worked by letting his truck slide over rocks in precarious situations.  S&S Plastics came through with more Delrin for me to design my own little rails.  They work just how Dumont’s do and added that much more performance enhancement.  They look pretty cool too! (Picture 11) 

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Typing and talking about this rig just don’t do it justice.  Pictures are nice but seeing it in person, as well as many other scale trucks out there, is a must to appreciate the time and effort that goes into these crawlers (Picture 12).

Guys like David Diaz, of Diaz Designs, who are constantly thinking up new ideas for our evolving niche will certainly further this part of rc crawling.  With his new parts and availability through his website, as well as others that are making scale rc parts, you too can start and finish a project like this. 
Now….to start switching bodies (Picture 13) around….and maybe…just maybe….it’s time for another new project!  After all, there is this Proline Bushwacker/Land Cruiser body that needs a home, a Defender 90 and the all new Proline Ambush that bares a striking resemblance to the old International Scout.  Nice!  Until then………

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