Thank you Airtech!

A sampling of donated Airtech materials.

We are super excited to announce that Airtech recently became a large materials sponsor of CalSol! The largest manufacturer of vacuum bagging and composite tooling materials, Airtech has generously donated some of their materials for our use on Zephyr’s shell. Since we have decided to go with pre-imprepregnated carbon fiber this time, we needed all new bagging materials that can withstand the elevated curing temperatures. We’ve also upgraded some of our other equipment, which will hopefully allow us to make an extremely nice shell for Zephyr.

Our new partnership with Airtech will give us the opportunity to improve our manufacturing process as we get ready to build CalSol’s most competitive vehicle yet. Thank you Airtech!

airtech adv materials logo blue and red

Shell Mold Work

Today we picked up the first of our new molds for Zephyr from Kreysler and Associates, who have been kind enough to continue their sponsorship of CNC and personnel time to machine our molds. After helping them out by clearing away all of the excess styrofoam, we transported the top and bottom shell back to Richmond, and got busy with a huge sanding session to smooth out any bumps and machine paths left on the mold surface. After months of staring at the Zephyr computer model, it’s extremely exciting to see the body of the car slowly take shape!

Sam standing in a sea of stryofoam
Sam standing in a sea of stryofoam.

The next steps will be to coat the molds with Duratec Styroshield (to protect the styrofoam, which reacts with the sanding primer) and then with Duratec EZ Sanding Primer. This will then be sanded and polished so that we can make female fiberglass molds that are extremely smooth. The final step is then to do the actual carbon fiber layup inside the fiberglass molds. Every bump and mistake will only magnify as we make the fiberglass molds and then our carbon fiber parts, so we are taking extra care to ensure our final parts will be shiny and smooth!

Our sanding party!
Our sanding party!

Last week Kreysler also machined 1/7th-scale molds that we are going to use as a practice for the real deal. Every step we have to do on our actual molds will first be tested on these so that we can iron out any mistakes before working on our full-size parts. The practice molds have all been sanded and are ready to be coated in Duratec. Check out how nice they look!

Small scale Zephyr molds.
Small scale Zephyr molds.


Tuft Testing at the Alameda Naval Base

Monitoring tuft behavior with a GoPro camera.

Yesterday we had the awesome opportunity to do some aerodynamics testing at the abandoned naval airstrip in Alameda, thanks to Makani Power. For those of you who don’t know, this is the same location that Myth Busters uses, though unfortunately (or perhaps fortunately), we were alone on this stormy day.

CalSol used the chance of having a flat, deserted, 1.5 mile long runway to get some data on the aerodynamic performance and rolling resistance of Impulse. For tuft testing, we attached small pieces of brightly-colored yarn to critical areas of the car (such as the leading and trailing edges, and around the canopy) and videoed the performance of these tufts while driving at high speeds. This allowed us to confirm CFD results generated by software and to see where the flow separated from the car. We also performed coast-down testing from high speeds to determine both aerodynamic drag and rolling resistance.

We plan to use this information to update our CFD environment to reflect more real-life conditions and to pinpoint improvements to make for our next car, Zephyr.

We had a lot of fun during testing and would like to thank Makani Power again for this great opportunity.

CalSol poses with Damon Vander Lind from Makani Power.

CalSol’s First General Meeting!

Last Wednesday, September 5th, CalSol had its first general meeting of the semester. After two weeks of recruiting, including displaying Impulse at Engineering Student Orientation, we expected a large crowd of interested newcomers to attend this first meeting and learn what CalSol is all about. However, I think the number of people who showed up even exceeded our expectations — by our count we had 131 people present!

It was great to feel the excitement in the air as interested students settled down into their seats to hear about CalSol’s past, present and future, including our plans of racing in ASC 2014 with a brand new vehicle that they will get to help design and build. Speaking with people afterwards and seeing their interest in the team brought back memories of my first CalSol general meeting two years ago, which I left wide-eyed from excitement, knowing that I had joined a club full of opportunity for hands-on projects and new friendships.

I know I’m not the only one when I say that I’m excited about the potential of this new group of students, and am looking forward to what the fresh blood in CalSol will bring for the team!

Painted Perfection

Impulse with a Fresh Coat of Paint from SAC

After working on numerous repairs to Impulse’s aerodynamic exterior, including making a new canopy out of carbon fiber composites instead of PETG plastic, we dropped off Impulse at Shattuck Auto Collision Center (SAC) this past Monday, and waited excitedly to see her return with a brand-new paint job. This morning our wait was finally over, and we picked up a sexy-looking Impulse from SAC. As always, we are very impressed by the great job done by SAC, who not only made Impulse look great, but also smoothed out any remaining textures to give her a sleek and aerodynamically favorable painted outer surface. Since every bump or tiny hole will add up to produce more energy loss from aerodynamic drag, the smooth surface finish is a great help in boosting our aerodynamic performance.

Nicole looks pretty happy with the new canopy!

Now we are working hard on last-minute preparations for Cal Day (which is next Saturday!!), including reattaching some solar cells that were removed during the canopy repairs and putting on new sponsor logos. We are also hoping to get some testing done in this wonderfully sunny weather, leading up to a test drive next weekend to Sacramento, right after we show off our car in the Etcheverry breezeway. We invite everyone to come out and see Impulse, with her new paint job, next weekend from 10AM-3PM.

Thanks again SAC!!

Safety First!

As our members get ready to leave for Australia, we are making final preparations to ensure that the team will be safe during the trip. Thanks to help from our partners at Fastenal, our friends at the RFS, Carlos Miller (a bay-area firefighter), and UC Berkeley’s EH&S, we have our bases covered.