Wham, another solid week of productivity from UA Baja Racing!  A ton has happened this week thanks to a lot of hard work from the team.  The shop is now primed for the build, Tomcar continued to impress, final design decisions were made, and the final drive of the 2007 vehicle was gutted.

A week ago on Friday the shop received its final touches and a deep cleaning.  Everyone from the team pitched in a few hours here and there since the beginning of the semester to weed out the old and useless to make room for the new and improved. 

Here is a little history on the SAE Shop:

Back in the day (a few years ago) the SAE Shop was shared by [then] Mini-Baja, Formula SAE, and Solarcar.  Solarcar had ½ the shop; Mini-Baja and Formula each were allocated a ¼.  Solarcar performed well in their competition, moved to a new shop, but left a ton of junk on their half of the shop.  In other words, half the shop was used for storage of their old stuff. 

Slowly Formula grew and began to help Solarcar compact their storage, hence granting Formula more shop space.  Mini-Baja was still in a corner of the shop with low/no membership and lack of team motivation.  When I first came to the University on a high school tour we visited the shop with the Engineering Ambassadors.  I was intrigued that students could build racecars in their spare time for competition, and I instantly wanted to get involved.  The only problem; Mini-Baja was a pile of junk in the corner, Formula was crammed into 3/8 of the shop, and Solarcar left their remaining storage a mess.  As cool as these projects were, I was slightly turned off by the lack of professionalism exhibited by the current teams. 

Last year, as sophomores, we were able to establish a team infrastructure with a stable build.  Our shop space was limited to less than a quarter of the shop with part of our quarter occupied by an old frame, a dismantled V-8, numerous piles of junk metal, and destroyed hubs and brake rotors.  Needless to say it was a tight squeeze.  We made it through, our car made it through competition, and we came into the 2007-2008 race year with great ambition.  It was difficult to keep a shop full of old junk clean, but somehow our team made it work.  Solarcar was fully out of the shop by then and Formula apprehended ¾ of the shop leaving our new team with the bare necessities. 

Now frankly, whenever a tour came to the shop I was embarrassed for our organizations.  Dust, dirt, metal shavings lined the floor by the door and all through Formulas section, old parts were lying around on the ground, and oil puddle could be found here and there, workspaces were cluttered with tools, debris, old food… it was disturbing.  What little of our shop that was viewable from the door was clean yet cluttered with old, ownerless junk.  I knew the status of the shop reflected poorly on our organizations yet nobody outside our team really cared, nobody thought our team would ever succeed (hah).

This year we did some massive cleaning.  One of the guys took the V-8 to rebuild for his senior project’s engine, the old/decrepit rotors/hubs were junked, the usable metal was salvaged, the old frame was chopped for scrap, we took inventory of all the tools, and we made a new welding table.  Here’s one thing I am thankful for, our whole team holds shop cleanliness at the highest of their priorities.  Not only is that good for the build, safety, and visitors, it also is a great primer for working in the industry once we graduate.

Check out the new[er] digs:

Tomcar Part II

After our visit with Tomcar a few weeks back we made a list of parts that would be useful for our 2008 build.  With Tomcar on our team we will be able to charter some new areas of design by having strong, reliable parts to work with as a base.  As some of us might remember, last year at South Dakota a dozen or so teams had huge problems with Polaris parts.  Tomcar = bulletproof (literally).

So what all are we using from Tomcar?  How will these parts benefit our team? 

Let’s start with the drive-train, beginning at the engine shaft…

CVT: Tomcar does all their own in-house engineering, among their parts is a custom continuously variable transmission.  Completely dust-proof and highly tunable, their CVT will allow us to hone our transmission for our vehicles characteristics or to our likings.

Gearbox and Differential: The CVT hooks up right against the custom Gearbox/Differential setup.  Tomcar offers several different gearbox setups in their several models, among which is a high-low-reverse box complete with a locking differential.   Not only is the differential lockable, it can be engaged on the fly.  So imagine driving up a hill and losing traction.  Normally the vehicle would need to come to a full stop before engaging the locker.  With Tomcar, you start losing traction and just slide the locking lever on the shifter and BAM, traction. Now that’s cool.

Final Drive: For the final drive we will be using components from the Tomcar chain-driven swingarms.  Not only do chain driven swingarms increase ground clearance and suspension articulation, they also can create anti-squat, or lift.  Under acceleration a vehicle normally squats in the rear due to the physics of conventional drive-trains.  With the location of the chain-driven sprockets that torque is displaced and thus the swingarms are “pulled” down and under the vehicle, creating rear-end lift.  This will benefit the vehicle in rough terrains, under acceleration, and if the vehicle becomes high-centered that extra lift might just be enough to free the vehicle from the obstacle.

Suspension: Four custom shocks will be featured on UA Baja’s new vehicle.  Another sweet thing about Tomcar, they build and manufacture all their own suspension components.  Even better, (all you off-roaders would appreciate this) if you happen to be out in the dirt and you blow a shock from dropping too hard off a rock, that blown seal will only cost a few bucks to replace.  No new shock is needed, and the parts to replace the blown component are easy to swap.

Steering: Tomcar builds custom rack-and-pinion assemblies for their vehicles, one of which will be turning the 2008 UA Baja vehicle.  I’m sure at some point or another you have experience a bent tie-rod on a steering assembly whether in your personal car, on an ATV, or in Baja SAE events.  Forget about bending tie-rods, Tomcar found the best solution… Everyone should know that a system is only as strong as its weakest link.  Therefore, the ball joint which connects the rack to the tie-rods is designed to fail under tremendous stress.  Granted, rough wheeling in the rocks might destroy a rod-end, but with a wrench and two minutes of repair time you are set to go.  That is way easier and less expensive than stocking replacement tie-rods, or even banging one back into shape with a hammer.

Huge thanks to Tomcar!

Final Drive Revamp for the 2007 Vehicle

So last weekend some awesomely bad stuff happened.  We already knew our spindles/hubs were awful, after all one snapped during the South Dakota Competition.  With them “repaired” we took the 2007 out for some fun in the parking lot and on the nearby staircase.  The new sprocket on the final drive increased our gear ratio to 14:1, instead of that lousy 3:1 we had before.  That gave us enough torque to be able to start from a standstill on a set of 45 degree stairs.  

Well, it was fun while it lasted…  While the car now had the torque to get up inclines, it apparently didn’t have the material properties to control the torque.  For some reason the spindles we recycled off the 2005 vehicle were made from two pieces which slotted together via a keyed channel.  Yeah, that channel turned from a rectangle to a trapezoid, the key blew apart into three pieces, and the car stopped due to the open differential.  At first it sounded like the chain to our differential blew, but then we noticed the left half-shaft rotating without the wheel following.

Hooray, so now we can do things the right way!  Mike’s going to be machining some new spindles out of steel (not crappy aluminum) Friday afternoon.  After those are swapped the 2007 ought to be able to withstand a small tornado.

More fun to follow this week. Going up to Tomcar this afternoon to pick up the new parts! Check back tomorrow for a video interview with Tomcar!

Copyright 2008 UA Baja Racing :: University of Arizona :: Tucson, AZ 85719