F1 in Schools Project - Materials

[Doliveira97]

Hey there! I'm participating in the F1 in Schools challenge for the second year now and would like to gather some pointers on which materials to use for the external components, including wheels, axles and aerofoils (wings).

We're looking for materials that are very light (we want to reduce the mass as much as possible) but also mechanically strong, whilst minimizing drag obviously.

Last year we used ABS wheels, axles and aerofoils. The ABS was a satisfactory choice as a material for the wheels, in terms of performance, but it was a problem when it came to the axles or aerofoils since it wasn't mechanically strong enough.

I was also looking for guidance when it comes to picking bearings. I've made a quick search on this and the variety offered for the competition is huge. I don't really know which type of bearing to pick and where to purchase it.

All help is welcome and thanks in advance, really appreciate it.

[Ledon Racing]

What are you actually building? Do you have any more info?

[Doliveira97]

I'm sorry, my bad, thought you knew about the project. We basically build a small F1 car made out of balsa wood, by first designing in a CAD software of our choice and then machining using a CNC machine. Here's their website if you wanna look up some more info:

http://www.f1inschools.com/about-the-challenge/

[tok-tokkie]

Bearings come from BOCA Bearings in USA. Use the all ceramic bearing. They have a pages specifically about F1 in schools. Wash all the grease out with acetone.
To minimise weight try using a hypodermic needle for the axle. Hypos are in strange imperial sizes so you may have to spin them in a lathe with a diamond file to get them to match the bearing.

[xpensive]

All ceramic bearings might be an overkill here Tok, I would rather go for Hybrids or coating such as DLC, xamples;

http://www.skf.com/group/products/beari ... index.html

[SiLo]

I remember building my cars during these projects out of a thick styrofoam. It could be moulded and sanded really easily. Then you can cut drag by coating it in shrink wrap plastic.

Or you could try balsa wood, incredibly light and with good structural rigidity.

[marcush.]

coatings are usually on the cheap side .And if you speak nicely to people they usually are more than willing to help ...
You guys are the next generation of potential customers -and any sales guy would be a fool to be arrogant and blasphemic now because of future deals not pushed or not even considered because of bad memories..
Position yourself as the next gen of engineers developing machinery and you have the door half open....

[Ciro Pabón]

Basizeland received a lot of help for materials and bearings for his F1 in School project, some years ago.

He used ceramic bearings and won Australian National Finals. I believe he ended fourth at Singapore in the Asian Finals.

The Basilisk


Perhaps his thread can be useful (it has over 200 posts): http://www.f1technical.net/forum/viewto ... =14&t=7438.

I believe Izzy and Flynfrog were his most enthusiastic coaches (apologies if I'm forgetting someone).

[fischele]

If this is still relevant,
we used polyoxymethylene (acetal) for our wheels. It's just about 2,4g/cm³ and quite rigid. We tested our wheels by putting stones on top of them and used a reversed 3mm drill bit to simulate a punctual load (very scientific, I know). They didn't deform even when we put 15kg (33 pound) on top. This year, we want to use magnesium instead. It's density is about 1,8g/cm³ and should be stable up to a load of 60kg (132 pound) in simulations.

For the body we used PU foam. It basically is a very dense kind of styrofoam and very easy to machine.

Every other component was made of 3D-printed ABS plastic.

We used aluminium axes.

[tok-tokkie]

Nice alteration on the wheel material - significantly lower mass. I wondered about making the tread section taper from min diameter at the sides to max diam at the center to both limit the ground contact & make a slight squirt area for the air. I know that the tolerance is really tight & that the car hardly contacts the track initially.

Using PU foam is great - I thought the rules required balsa. There are special PU foams of various densities made specifically for prototyping (I am aware of German made) that are really consistent and uniform. Much more suitable than PU foam aimed at thermal insulation.

[poryongming]

Actually, POM/Acetal has a density of 1.4g/cm3, not 2.4g/cm3. Therefore it is less dense than magnesium and probably more rigid too, unless you are referring to certain magnesium alloys. I'm not sure if there is any benefit in using any kind of metal, over plastics such as POM/Acetal and ABS for this application. The lightest metals are still significantly denser than standard structural plastics.

The rules of F1 in Schools have changed and balsa wood is no longer used. All car bodies must be CNC machined from a standard block of polyurethane foam supplied by the organiser. The nose, wing support structures and wheels/axles can be made of any material.

[fischele]

Actually, POM/Acetal has a density of 1.4g/cm3, not 2.4g/cm3. Therefore it is less dense than magnesium and probably more rigid too, unless you are referring to certain magnesium alloys. I'm not sure if there is any benefit in using any kind of metal, over plastics such as POM/Acetal and ABS for this application. The lightest metals are still significantly denser than standard structural plastics.

Yes, density is 1,4g/cm³.

We are using Magnesium AZ80, it's far superior to POM in stability.

[RaulRof]

Ive got to replace my butterfly seals. Since you just took yours apart I was wondering if you thought it might be possible to replace the seals with out taking the whole shaft out?