December 2, 2010
The team made a list of pros and cons for building a new car, its design, & component configuration.
Two front wheels
We have experience with this design.
It’s a proven success by many other teams.
Stability is better
We had a complication with designing the steering.
We had less leg room because of steering.
One front wheel
It seems to be a simpler design.
It is easier to build due to our time frame.
It will be easier to exit and enter the car.
The rear axle might be under more stress.
It could be harder to align the rear drive sprocket to drive axle.
It could be a rollover hazard on tight turns (if weight distribution is not right).
The team measured and drew out the frame as a template for the body shape on a 4X8 sheet of plywood to form to our drivers’ shape. We are going with tear drop design with wider center body to conform to our drivers.
December 9, 2010
The team salvaged front fork/ frame for front steering from trashed bikes. Cut fork away from body of BMX bike frame.
The team cut two, 1-inch 16 gauge square pipe to 10 foot lengths for the body’s base frame, three, 1-inch 16 gauge square pipe 6-inch length, for brackets. Welded frame (two, 10-foot square) pieces together for main body frame with 6 inch pieces. Placing three, 6-inch pieces on front, back, & middle to form main frame for body.
We cut two, 20-foot 16 gauge, 1-inch round pipes to 10-foot sections for side frame pieces. This gives us 4 pieces to fabricate body side panels.
The team then used the template made earlier as a guide to lay 10-foot round pipe sections, to mark bending points on pipes, making each piece identical. We bent the four, 10-foot round pipes to make aerodynamic side frame pieces, using pipe bender and checking each bend with template. Using the pipe bender and template made it easier to get each piece exact.
We discussed rear axle drive differential complications and possible solutions:
1. Drive one wheel with the motor and free wheel other wheel.
2. Have 1 front wheel drive and 2 rear wheels free wheel with braking.
3. Apply differential to rear axle.
December 11, 2010
The team discussed the rear drive issue, found after conferring with ‘go- cart builders’ that differential would probably cause more drag on batteries (draining them early). Go-cart builders use different size tires (diameter and width) to take up the difference in wheel turn on cornering (left turns). The go-carts do drag/skid in corners, but more because of speed and driving abilities.
After further discussion and calculating radius for wheels, it was decided to use the twos on rear, one driven wheel and one free wheel. We feel this will help in the issue of outside wheel turning more in turns, by freewheeling and not drag/skid into corners by being ‘driven’. These rear wheels will also be our braking wheels which should give us a better braking ability.
Finished bending 1 in. 16 gauge 10 foot round pipes to form side body rails, continuing to use body shaped template & pipe bender.
Fabricated 8-inch by 8-inch square, for toe guard, out of 1-inch 16 gauge square pipe, welding them together into a square shape, and welded to front of main frame of car. Also made an 8-inch by 8-inch square frame for bracket on back to attach side rail pieces. Welded this to rear of main frame.
Fabricated rear and front mounts for side body rails to weld to main car body, out of 1-inch 16 gauge square for rear mounts, 1-inch in length. Bent front mounts with tube bending machine to form body shape desired, using 1-inch 16 gauge round tube. Welded mounts to main frame of car body, front and back.
Fabricated and bent two, 1-inch 16 gauge pipes into an arc to support side frame pieces on front, for welding side panels to.
Welded right/left 10-foot pipe pieces, side frame rails, to mounting brackets on main body of car. There are two on each side to make form for our car. This forms our car shape and will protect driver for any side impacts. Bent two 16 inch 1 inch 16 gauge round pipes to support side panels and connect them to main frame. Welded the two support pieces to car main frame and side panels. This gives us our maximum 6-inch opening as required by the rules also, as side panels are 5 and ¾ inches apart.
January 6, 2011
Discussed plans for front single wheeled steering. Decided to use front fork assembly from BMX bike. This will work much like a motorcycle, giving a simpler assembly and give us a good turning radius.
Used balance board to figure where the key components of the car need to be placed so weight will be better distributed. Marked on the balance board the driver position and other main components where they would be placed inside the car.
Transferred measurements from balance board to the car frame. Started design for the mounting brackets for rear axle on a dual rear wheel setup. Decided on ‘A’ frame style brackets for rear axle, much like an ‘A’ frame used on an automobile’s front suspension.
January 13, 2011
Fabricated rear wheel bearing mounts using same design as an A-frame on a front end of a car out of 1-inch 16 gauge square tube and 1½ by 1½-inch steel angle iron.
Bent and fabricated rear seat support out of 1-inch 16 gauge round tube. Used bending machine to contour the seat support. The support now forms to the back of the driver. Fabricated two support brackets, to brace the back support, to the main body frame. Welded back support & brackets to main frame in driver location (from balance board).
January 20, 2011
We welded the A-frame wheel mount to main frame. Fabricated support brackets for A-frame and welded to ‘A’ frame and side panels to support the weight of car body.
We redesigned main frame to accommodate front wheel radius for turning. We cut 16 inches of main frame on both sides to make room for the tire. We then discussed ways to support the front frame of car. We decided to use 1-inch round 16 gauge tube to support the main frame for front steering and wheel well. We bent the 1-inch 16 gauge to a 160 degree arc to accommodate turning radius. We cut the ends off at an 80 degree angle to weld to body frame. We tack welded the wheel well to the frame of car.
February 28, 2011
We have been finishing up the body for our A111new car, adding mounting brackets for the components (batteries, motor, controller, and driver). We finished the front steering fork and mechanism to allow the best steering for his car. The team did some designing to fabricate the roll cage to ensure the driver will be protected at all times and give the point of support in case of a roll over.
The team built a battery test station using the information received from the instructor worship this summer. We received four new batteries from one of our sponsors and will begin testing them in the next two weeks to pair up batteries and find the strongest.
The team has been discussing a name for the car and color scheme, but haven't made a final decision yet. It seems to be a different idea for this which the guys have been looking at. We hope the weather cooperates so we can get some driving time in this next month and get the new car out to teat it!!!!
March 31, 2011
We worked hard to complete the N111 car, but fell short on time. It was time to make a decision on whether to continue or ready S2. After a timeline of what we still needed to accomplish and the amount of time before first race it was decided to ready S2. We had some trouble with the drum brakes on S2, so we looked at disc brakes. One problem was our disc brake wheels were smaller axle size than the drum brake wheels. It was decided to take the smaller size axle spindles we had in storage and adapt them to fit S2. It was a bit of a challenge, but by adding a steel tube between the mounting holes on the smaller spindle we were able to adapt them to fit. We were able to use the right side brake caliper mount, but had to make a mount and weld it to the opposite side of spindle. We also changed from a foot pedal brake to a single hand brake on steering wheel as we have two size drivers. Test drove car for the first time and found we needed to get a better fit on our spindles. By welding a washer above and below mounting holes on spindles we were able to get a tighter fit. We will test drive one more time before Friday and Saturday rallies.
April 1, 2011
Today, we raced at the rally in Columbus, NE at Ag Park. We didn’t do as well as we were expecting by only completing 5 laps in one hour. We had three flat tires and accidently shorted the motor when the battery jumped out of its holder and the terminal touched the motor. We ended up having to pack-up early because we didn’t have a back-up fuse when it blew about forty minutes into the race.
We found out what was causing the flat tires and fixed it. The problem was that the steering arm was bent at an angle therefore causing a down and out push on the tire and then when we turned, the pressure on the wheel kept causing it to pop. To solve the battery problem, instead of having two straps holding down both batteries, we moved the straps so each battery would be held down by one strap therefore the straps could be tightened even more. To give us more room so if the batteries jumped out of there holder, we put in a smaller, less bulky motor.
April 2, 2011
Today, there was the rally in West Point, NE, at the Cuming County fairgrounds. We completed the race very well and had one flat tire and also drove on a bent axle for 3/4 of the race. We completed 37 laps in one hour to win first in Novice Class.
We bent the axle back to its original place and also changed the 20in. wheels to 16in. wheels. We also changed the brake calipers to fit the smaller but thicker disc brakes.
Due to all team members taking ACT tests on April 9, we did not compete at the Hastings rally. We have been working on documentation and straightening out the shop.
Due to Jr.-Sr. prom, we did not complete at the Rally in North Platte on April 16th.
We will continue to make final adjustments to car S2 to make sure all safety features are correct and operational. We also plan to make sure to check all mechanical and electrical systems as well. We will practice pit stops and driver changes as well as do some testing to make sure all requirements of the car are met before the state finals on May 7. We will install new front wheels and tires that match a set that have been ordered to be used as a backup set of tires and wheels. This will make tire changes quicker as we will be able to change the tire and wheel as one unit instead of having to remove tire(s), replace tube(s), and reinstall the tire. This is one of the biggest lessons we learned this year. Having back up parts available to repair will speed up pit stops and keep us in the competition longer.