2004 Texas A&m Fsae Update
03-19-2004, 12:19 PM
#32
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That is bloddy excellent 
, but $25,000 is a hell of a budget - where does it all go? What I am building is pretty much a road legal version of one of those, but I am only spending a fifth of that - I'm getting goosebumps thinking what I could do if I had $25,000 to spend .
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03-19-2004, 12:45 PM
#33
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Originally Posted by inanimate_object' date='Mar 19 2004, 01:19 PM
That is bloddy excellent , but $25,000 is a hell of a budget - where does it all go? What I am building is pretty much a road legal version of one of those, but I am only spending a fifth of that - I'm getting goosebumps thinking what I could do if I had $25,000 to spend .
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mark
Engine, fuel management.
Custom made components that is costed at 70 bucks/hour for CNC machining.
You have to cost the process and the cost of each purchased component down to nuts and bolts. Each bolt (shoulder bolt) is costed at 2 dollars a bolt. There are hundreds of them on the car.
03-19-2004, 04:45 PM
#35
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We don't actually spend 25,000 dollars. The value of the goods + our labour equate to 25,000 dollars.
Goods come from sponsors, so if we need nuts and bolts, we may got an industrial supplier and they give it to us for free or sell below cost to us. Our CNC machine time is free, because the students use it, with the supervision of the school's machinist. THey teach us what to do and we do it ourself.
The engine depends on the team. We use a suzuki DRZ400, with a bigbore kit to 470cc single cylinder. We use a Tec3 which cost us big time dollars. Even at cost and trade in of our old Tec2, it cost 1700 cdn.
We think we can match the performance of our single compared to a CDR600. Some teams run turbos. We wish we could, we are only in our second year with a DRZ motor. We have three of them. two are pooched. We blew the bottom end, the other had the connecting rod break into two peices. We was pretty amazing when we blew the head, the intake cam split into two peices at competition last year.
GM provides a mahcine shop at the compeition for all schools, we couldn't find a stock or aftermaket in detroit. So GM shrunk a metal rod with liquid nitrogen and fit it into the hollow cam to make it into once peice. It was like OMG i can't believe u did that. It was funny too, 10 machinist with more then 20 years experience each couldn't figure it out until the last guy thried this.
Goods come from sponsors, so if we need nuts and bolts, we may got an industrial supplier and they give it to us for free or sell below cost to us. Our CNC machine time is free, because the students use it, with the supervision of the school's machinist. THey teach us what to do and we do it ourself.
The engine depends on the team. We use a suzuki DRZ400, with a bigbore kit to 470cc single cylinder. We use a Tec3 which cost us big time dollars. Even at cost and trade in of our old Tec2, it cost 1700 cdn.
We think we can match the performance of our single compared to a CDR600. Some teams run turbos. We wish we could, we are only in our second year with a DRZ motor. We have three of them. two are pooched. We blew the bottom end, the other had the connecting rod break into two peices. We was pretty amazing when we blew the head, the intake cam split into two peices at competition last year.
GM provides a mahcine shop at the compeition for all schools, we couldn't find a stock or aftermaket in detroit. So GM shrunk a metal rod with liquid nitrogen and fit it into the hollow cam to make it into once peice. It was like OMG i can't believe u did that. It was funny too, 10 machinist with more then 20 years experience each couldn't figure it out until the last guy thried this.
03-21-2004, 07:52 PM
#36
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Originally Posted by Cheers!' date='Mar 18 2004, 09:57 PM
Can you give more details? Yes i agree the shocks are stiff when the spring is installed with preload. I have actually never taken off the spring to get the shock by itself and seeing how stiff it is.
What spring rates are u using?
I'm not sure about the prodampening, the shocks we run are from the 2002 model year.
We are using roughly between 0.6 to 0.9 installation ratio for the rear, the front is roughly 0.8??? i think, i can't remember. We too use almost the full range of the shock travel.
What type of suspension are you using? pull or push rod system?
What is wrong with CNC? it's great, you program it and you go home... we have 3 brand new HAAS CNC machines, one of which have auto tool change. the other two are not, and there are 2 older older CNC machines.
we also ahve three CNC lathes
Solidedge can save an IGS file, and then you load the IGS file into mastercam mill/lathe9 and u define the tool path, could'nt be easier. We'll easy for several on the team.
The precision and speed of CNC is amazing.
Our body is made from Al skin-Balsa core sheet, used normally to line hte floors of cargo planes. Strength and stiffness is amazing, unless it gets wet... water + balsa core = rot = crash.
Our car is made into a monocoque for the front with an chromoloy/mono hybrid this year. The only thing fibreglass on the car is the front nose cone, i think it's 3 layers of fibreglass, took 2 people 3 weeks to shape it they would say they made it. the fibreglass is purchased from UScomposites, it is 6 oz e glass cloth.
The nose cone can be taken on and off in 5 seconds, no suspension peicies need to be removed, think of cart/irl/f1 style nose cone, except our does not carry any loads.
We use a diff off a honda ATV, it is more then 1/2 the weight of a zexel torsen unit. I'm not sure on teh specs.
Our halfshafts are also from some ATV. We modify them on the CNC lathe.
The wheels are bogart racing, super light, it think each wheel weighed in at less then 7 lbs each? i can't remember.
What spring rates are u using?
I'm not sure about the prodampening, the shocks we run are from the 2002 model year.
We are using roughly between 0.6 to 0.9 installation ratio for the rear, the front is roughly 0.8??? i think, i can't remember. We too use almost the full range of the shock travel.
What type of suspension are you using? pull or push rod system?
What is wrong with CNC? it's great, you program it and you go home... we have 3 brand new HAAS CNC machines, one of which have auto tool change. the other two are not, and there are 2 older older CNC machines.
we also ahve three CNC lathes
Solidedge can save an IGS file, and then you load the IGS file into mastercam mill/lathe9 and u define the tool path, could'nt be easier. We'll easy for several on the team.
The precision and speed of CNC is amazing.
Our body is made from Al skin-Balsa core sheet, used normally to line hte floors of cargo planes. Strength and stiffness is amazing, unless it gets wet... water + balsa core = rot = crash.
Our car is made into a monocoque for the front with an chromoloy/mono hybrid this year. The only thing fibreglass on the car is the front nose cone, i think it's 3 layers of fibreglass, took 2 people 3 weeks to shape it they would say they made it. the fibreglass is purchased from UScomposites, it is 6 oz e glass cloth.
The nose cone can be taken on and off in 5 seconds, no suspension peicies need to be removed, think of cart/irl/f1 style nose cone, except our does not carry any loads.
We use a diff off a honda ATV, it is more then 1/2 the weight of a zexel torsen unit. I'm not sure on teh specs.
Our halfshafts are also from some ATV. We modify them on the CNC lathe.
The wheels are bogart racing, super light, it think each wheel weighed in at less then 7 lbs each? i can't remember.
as for CNC, as you said, it cost $70 / hour, and weldments are much cheaper. we're trying to decrease the cost of our car, since in teh past is has been like around $17K, and last year michigan state was only like $9500, and they got like 3rd place overall. we need a cheap car to compete, so we went with weldments. only our hubs and a few parts of our drivetrain our CNC, everything else is welded steel alloy or machined by hand.
our spring rates are supposed to be 250 front and 350 rear, but that might change when we start tuning. front will probably be more like 300 since fox sent us 900 on our new shox.
were using pullrod. i like where we can place the shox, and it doesn't matter about airflow for our competition, so i just did outboard shox with the pullrods. also, we dont have to worry about the pullrods buckling and can make the smaller, which is not the case with the pushrods.
our whole car is just chromolly tubing with extra car paid to triangulation for increased rigidity.
we used WinGeo software from Mitchell Suspension Software to place our rollcenters, VSAL lenghts, and control RC migration and camber change rates.
we used a combination of rigid and pin joints in AlGor software to build our chassis and get a high stiffness to strength ratio.
03-21-2004, 08:00 PM
#37
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Originally Posted by inanimate_object' date='Mar 19 2004, 12:19 PM
That is bloddy excellent , but $25,000 is a hell of a budget - where does it all go? What I am building is pretty much a road legal version of one of those, but I am only spending a fifth of that - I'm getting goosebumps thinking what I could do if I had $25,000 to spend .
mark
mark
Wheels: $1200
Tires: $700
Brake System: $700
CNC Hubs: $500
It adds up quick. these are just a few of the rough numbers.
03-21-2004, 10:51 PM
#38
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Originally Posted by Apex13B' date='Mar 18 2004, 11:09 PM
that exactly what i do, pivot points cardboard mockups and good old pen and paper
PS...you dont need to redesign the FC's suspension...its very good
PS...you dont need to redesign the FC's suspension...its very good
03-22-2004, 09:32 AM
#40
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Originally Posted by Travis R' date='Mar 22 2004, 09:07 AM
Yes, I'm with UT in Austin.
How much did that bearing cost you for the diff carrier... It's friggin' HUGE!
How much did that bearing cost you for the diff carrier... It's friggin' HUGE!
yeah, i think it was like $300 or so. but b/c of it, we saved like 2-3 lbs in our new diff assembly.