Repairing Bernard !!
Making Vindaloo Hotter !!!
Updating Prometheus's systems ( not easy to say let alone do ! )
Finding more cash .
etc etc etc why oh why did I get involved , only a short time till the 2012 season opener - yes really.

We are looking to recruit new team Yr 8 members after Half Term to replace those in moving up to Yr10 . Doing some local schmoozing/sponsorship stuff with the local paper & displaying the car at a local Green Fair. Started to look at the PV thing and have made plans/designs with the kids to make good some aero & mechanical tweaks which will be our main area of focus this year. The car was designed with the 2013 regs in mind so it needs to last a couple of years before we build a new one. However, the Yr 10s are keen to desgin a new car already and run a seperate team and like a sucker I'm quite interested to put what we learned into use too. Still wonder how some teams are able to maintain constant (sometimes even turn-upable) current/voltage to the motor when our batteries are dwindling, wish we had someone here who was into electronics.

Hi Wheels - sounds like your going to have enough things to keep you busy this winter. ChasW the making good aero parts certainly will help - the subtle changes we made to Megazord for this season made a significant difference to our milleage. Good luck to both teams on finding more money - we will be doing the same when we understand what we need to take advantage of solar charging. My sixth form group have been building their own car since June last year constructed mainly from recycled / re-used parts and materials. I have to say that they are learning a huge amount from building a car themselves but progress is a little slow. The only electronics we have played with are the usual 4QD pulse width modulators but have reverted to a relay set up for the last three races. I have two students presently building a simple temperature sensor which should automatically turn on a fan to cool the motor but we have no data onboard to say what our current draw is at any time.

Anyone else busy?

Phill

New chainset and oil/filter on SKS Junior's motorcycle.
Fresh back tyre and re build the exhaust on mine.
Lining the shower cubicle with multi panel.
Last grass cut of the year.


Ah.... sorry.... yes, the cars.

erm........... quick release battery terminals.

Oooh, not much! Dismantle and rebuild FR-4 with a new chassis, new front end body shape for FR-1, and build the new FR-5M. Should keep everyone occupied I'd think. Anyway, that's the plan......

CC

A Brand New Build :) a Compete Rebuild and a service of a Goblin. Not much then...
http://hampton-racing.blogspot.com/ if anyone's interested in the new build.

I'm working on convincing my team to relegate this year's car to a year 10 test buck, then using the year 11s to build a new one... not getting very far so far. Think it'll be a rebody of this year's car with cruise control. Not sure about solar yet - will decide in the next few weeks.

We have 3 new year 7's and some slightly older ones that have not built a car from scratch. Also some of the older lads appear to want to compete in F24+. So I think the current view is that we will be making a new car next year (there are quite a few ideas buzzing around) but will try and modify the old one to match the new rules for F24+ and F24 earlier on in the season while the new one is being designed/built. We will see what the consensus at the next few Greenpower evenings are. It will also depend on what sponsorship the team can obtain.

Quite a few new cars being considered - that's a huge amount of work between now and April but worth the challenge. Today I managed to mount the gear train in place to make sure there was still enough space for battery tray and mounting the side panels. The axle sprocket was mounted onto its boss and slid onto the axle - now we simply have to bolt it in the correct place.
Front steering is done apart from tracking. Brake lights are in place but wiring needs tidying; we have quite a bit to do before we can test the new layout and I dare say some fine tuning and adaptations after a good shake down.

Phill

Back from half term and had another evening on the cars. More bits made such as roll cage for one and new display for Megazord. Team members have put a web site together that conveys what we are doing in a fun and humorous way. http://greenpower.bristolgrammarschool.org.uk/Home.html Next job is to make up a pair of wheels for the recycled 'subzero' car to replace the 18" ones on the front - they are tired needing spokes and truing so have decided to standardise with all our other spares.

Enjoy

Phill

A month on and a reasonable amount of progress made - new wheels built for Subzero taken from recycled parts; original hubs, donor wheel for correct length spokes and rims off another bike. We have altered the spindle height on the front axle to give the correct ground clearance and matched this on the rear bearing carrier plates. The rear is boxed in and motor mount fitted so it's rolling and ready for bodywork and electrics to get underway. This has by far been the best project we have worked on - the students make the decisions and make all the parts and my role is to carry out the welding in places where experience is necessary. We will be breaking up for Christmas in a couple of days but am already eager to get back in the New Year to carry on with the build.

Phill

Does size matter????
We're getting our ideas together, and are at the 'small & fast' vrs 'everyone can dirve' discussion phase. Does anyone have an idea how much faster a small car is compared to a large one, (which will be heavier & have a larger aero profile).
thanks,
Brian

I would say that it is worth making the car bigger for taller drivers. It will be mainly the length that is larger which is likely to improve aerodynamics and should not make the car significantly heavier. The car would probably not need to be much wider/thicker.
The lads, especially, grow so much during their time in F24 and I think that it would be a shame and possibly not good for team morale for them not to be able to drive a car they have had a hand in building (they can easily grow out of a smaller car during a 4 month driving season or during the build). We had to extend RR7 for almost every race to get them in, good experience for the team I guess, but a lot of work. RR8 was designed to take a 6ft+ person.

We're determined to start earlier this year even though our plans always seem to get put back. Anyway our original car is being retired after racing since 2006 so we're about to strip some of the uasble bits off it, hopefully that should get the new kids focussed.
We will build a new car to be ready for 2013 using everything we've learnt over the years as well as the enormous volume of info on the forum, looking forward to the build although if it takes as long as the last car it'll be ready for 2014 not 2013!
Good luck to all for a successful 2012, see you at Croft.

making a mould for cheese

^sorry i mean fiberglass^

Another evening spent on the Greenpower cars and progress is being made. Subzero had a floor made up tonight which will soon be riveted into place.

http://greenpower.bristolgrammarschool.org.uk/Photo%20Gallery/The%20Making%20of%20SubZero.jpg

Steering levers had to be moved forward and consequently linkage arms have been modified for the third time. We still have to make up sprocket mounts and start wiring along with fitting side and top panels. Gigazord has been a little neglected but thankfully I had a more experienced student helping tonight and decisions for mounting the overload switch and battery isolator have been made. Younger students made a great job of our battery trolley adding a jockey wheel. The newest Yr 7 recruits were given the challenge of drawing the cars on 2d design which they seemed to enjoy. Lots to do but we remain optimistic.

How are you getting on?

Phill.

Here a small redesign has turned into a major rebuild.
Ashley

Just started doing trials vacuum bagging parts for the new car. Some bits are done already, steering braking system, mould for monocoque and wheels. body/chassis is carbon fibre composite around structural foam - should be incredibly strong & reasonable weight. Codename dylan, martini racing colours ;^) Expect it to run before the end of the season......

Hi Ashley and Bob

it can be quite surprising where time goes on these builds. We managed to secure the floor to the frame on one car this afternoon (double free). The vacuum bagging is an ideal process if you know what materials work well with particular resins; do you have any details of the materials you use on the carbon fibre?

We will soon be in a position to join styrafoam to the cars outer panels to improve its shape but don't have any knowledge of the right adhesives to join the styrene blocks together. Can anyone offer any guidance please?

Phill

Hi,

We have emptied out the piggy banks, taken the plunge and purchased some bit and pieces from Michael / Greenpower and SJS cycles. The students are now designing, making and assembling all the bits that are needed to join the big bits together. Work is progressing in fits and starts, lunchtimes and evenings, the students are so keen it is unbelievable....
Follow the progress on http://teamscooby.blogspot.com/ feel free to comment, but the kids are updating it, so be gentle!!

We WILL be there at Silverstone .... just go to find the cash for all the other bits now!!!

Hi Phill,
We have used polyurethane wood adhesive (Gorilla Glue, screwfix no frills PU glue etc) to glue polystyrene. These adhesives need clamping/securing so the pieces don't slide around while it sets. They are close to the same density of the PS so they finish OK. We also tried PU expanding foam which does work, but you have to make sure the panels are VERY securely clamped as the expansion is v powerful. You can also use epoxy resin (not polyester resins as they dissolve PS) or purpose made spray on adhesives availiable from Bagpress. Have fun & Blwyddwyn Newydd Dda. Chas W

Hi Mr T
we stick styro foam together with epoxy resin filled with glass bubbles filler - this makes a paste that fills big holes without running away, doesn't dissolve the styrofoam & can be sanded quite nicely afterwards. The fibreglassing suppliers source it. When 'wet' it doesn't feel as though it's sticking at all, but once it goes off, it is well bonded.

Hi. I have used Polyurethane Adhesive too, works well and will cure quicker if you spray one surface with a fine mist of water before joining. I have tried Epoxy as well and the cure time is too long for me but it does work very well. If I ever build another car I will avoid Epoxy as it's use has added 7Kg to the weight of the car as that's how much resin I used.

Thanks for the advice everyone - looks like it's time to go shopping!

Another busy week and what looks like an insignificant amount of progress made on both cars - but steering geometry on SubZero now takes account of ackerman angles. http://www.greenpowerbgs.blogspot.com/
Next week the main focus is the rear axle drive.

Mr T

Slow progress in the Rotary Racer team. Some members are working on the RR8 car to meet the new rules (mainly dual brake cables), should be finished soon except we didn't buy enough brake outer. Its amazing that 3m of brake outer is not enough ! The new members are building battery boxes and bits for the RR+ team (the older lads are intending to race in the F24+ with RR8, if they get their funding act together ...).
The design for RR9 is progressing very slowly. We have been looking at different materials. The older lads are playing with designs in the VWT and getting the newer members to do some 3D-CAD entry, not sure if many of the designs will be practical, we will see. We did have a good team meeting on the new cars design tonight with lots of tape measuring around the old car and with pictures of possible designs. Lots of ideas, battery placement positions etc.
Mind you we don't have the funding to build it yet, members have been sending out letters to various organisations... A basic budget is being prepared, by some members as a basis.
So I don't think RR9 (no code name yet :) ) will be out this year, but you never know.
Lots of activity in the other CSS teams, new car building by Chain Reaction based on an aluminium ladder they got cheap somewhere, Alderney Express are re jigging their car for the season with lots of foam blocks in evidence and TPM are hard at work on T-POD.
We also got a smoke machine for the newly built wind tunnel so there was a lot of smoke around last week !

My main task at the moment is trying to persuade students that a cool looking design isn't the same as a race winning design........ It's strange having 4 years experience when all my students are starting from scratch. Not to worry, we've knocked up a 'coffin' to check our cockput dimensions & have got a friendly aluminium welder on board. We're planning to win something around 2017!
Brian, Magdalen College School, Brackley.

2017- a tad too far in the future- If you're prepared to work nights and weekends on it, you can build a car in 28 days. And win in it.

Vacuum bagging trials went well, first wheel built tonight, curing as I type! Reason for post, I've seconded our works 3d printer to make some small body parts on ABS so I made a small video about the process - might be interesting for some ;^)

Very cool! I like it a lot!

Excellent video Bob, I can see 3D printing becoming commonplace in the next few years, you can already get a "Rapman" for about £800 which is about the equivalent price of a desktop laser printer 20 years ago.

Got any video of the wheel build? Interested to know if you've gone single skin (like Bentley) or similar construction to Mjolnirs'

Hi gary,
we did a sort of cross between the two; we wrapped tape around the rim first so the skin(s) were bonding to that rather than the aluminium & the inner section is flush on the outside but only about 1/2 rim width (on a structural foam core). As we have "put a lid on the box", so to speak, I expect it to be very strong indeed - but time will tell. 2 heavy layers of carbon weave inside and out. The vacuum process just makes a beautiful job of the composite work, unbelievably light, strong and well finished. You have to spend time on preparation & setting your stall out, but once you've done that it seems to go pretty much by the book - we've had no vacuum problems (yet)

Totally agree Bob that vacuum bagging is just so much better than traditional lay up, the finished composite is better in every respect. Looking forward to seeing these new wheels, it'll be interesting to see how they stand up to the rigours of racing but you probably won't subject them to the same abuse as Mjolnirs'!

I think the Darley moor hairpin at 30mph is a match for Alford's corners, though it doesn't crop up quite so often!
Thinking about it we're putting an awful lot of hi- tech into this car: pukka F1 style composites work, additive manufacture, laser & waterjet cutting. I'm guessing we'll be spending a few hundred on carbon fibre weave too. Great to get the kids involved with all this stuff, & the car will still end up lots cheaper than a kit. Hope it goes alright after all the buildup........ It should be half the weight of Zebedee & Brian ;^)
Called in at the school to check out the wheel this lunchtime - yes, it came off the mould looking luvverly ;^)
We took a few photos while doing the wheel - I guess they'll end up on the website in the fullness of time.

Prometheus - -- total drive system being replaced with a radically different one !! The original system was a good guess at what was needed for our first car , but having had the benefit of 3 to 4 years running plus what was learned from our gearbox car ( vindaloo ) and the two races that Bernard ran confirmed our suspicions that "Promies" drive system was not the way to go ( which some of the " experienced sages " out there probably figured out first time you saw the car ! ) So Prometheus will look a bit different and sound a bit different , ( first front wheel drive greenpower car ??) .

Bernard --- buff up and polish !! plus parts that time did not allow to be fitted as we first envisaged now sorted.

Vindaloo---- a few steering revisions to make the handling a bit korma sorry calmer

Put in a full day on the car today - 1/2 term so we had the school tech room to ourselves ;^) 3 old heads and 4 (1 part time) girls took 5 hours to vacuum bag a monocoque half; single composite structure 2m x 0.6m, very 3 dimensional!
Can't wait to see that come out of the bag! (if it unsticks from the mould that is:- we have to use the mould again for the top half....)

Plume are:
1) Replacing the brakes on darkside of the plume with inferior cable brakes (will have to try and sell the beautiful hydraulic 2 into 1 lever setup made by magura).
2) Building an all new foam cored composite teardrop shaped car, which is veneered on the outside and looks like a racing parquet floor!!! very light, very strong, very exciting!!!
3) Considering an rebuild and reentry of projectile with a roofbox based shell.

You don't need to use cables- just use two hydraulic levers fixed together. Simples!

Can't wait to see some of the new projects - some superb use of technology going into the chassis of these cars. Our own projects have seen more attention given to SubZero which had its first roll down the school yard this afternoon to test steering and brakes - all students survived the experience. We had four sixth formers, one year 10 and one year 7 student helping out with very little input from myself, and for me this is exactly what I was hoping to achieve by getting involved in Greenpower. Still a huge amount to do if we are going to race two new cars this year.
Photos will be added next week.

Mr T

1st half popped out of the mould today
http://i543.photobucket.com/albums/gg471/bobc0/greenpower/dougalhalfoutside.jpg
http://i543.photobucket.com/albums/gg471/bobc0/greenpower/doughalfinside.jpg
nice

"Popped out" or do you mean dug out? Looks like it took some of the mould with it.

I can't criticise I often end up taking some bits with me when I mould something.

-Luke

Inevitable - mould is largely plywood so can't use warm water..... Nothing that can't be easily remedied! ;^)
"was prised out" might be more accurate....

Very pleased with our bottom shell now its off the mould, sat in it today and was bounced up and down by 2 other teachers......given that I'm a fair bit heavier than our average driver, I'd say its strong enough :D
Just got to do some surface sanding and varnishing to make it a bit prettier, but quite pleased with the "parquet floor veneering"
http://www.flickr.com/photos/projectplume/6911599197/in/photostream/
http://www.flickr.com/photos/projectplume/6911599447/in/photostream/

BobC- Good! So long as it stood up to it well enough to get your top half out!

Project Plume Power - "given that I'm a fair bit heavier than our average driver, I'd say its strong enough :D" I'd say it's too strong then :P Just kidding, Looks amazing. I'm dead impressed!

Can't wait to see it out, when can we expect it on track?

Luke

Not going to commit to anything just yet, it would be lovely to make the season opener, but there's still a HUGE amount to do and I really don't want to rush this car (unlike the last 3), I want to take the time to make it as good as we can and do some proper testing (at our new top secret 3mile long testing ground).

Other news is that our resident mad scientist has built an on-board computer with 2 way telemetry aka rotary racer and the bench tests so far are looking very very very pleasing!!

Needless to say that Darkside will be at as many races as we can squeeze in, still lots of development to do to the old girl yet.

Tony

Our car is currently having teething troubles at the stage of "trying to build caliper mount templates..."
This doesn't bode well.

Cookie, I have disc brake caliper mount dimensions if that helps - they're not as odd as they look at first glance?

The odd chassis build isn't helping, nor is the fact the wheels aren't symmetrical, due to a cvt hub.

Just spotted this.... looks very nice :)

http://www.sg.polsl.pl/index.php?option=com_phocagallery&view=category&id=68%3Amould-manufacturing&Itemid=12&lang=en

-Luke

Another new car from our Polish friends! And I'm sure this one will be as beautifully built as the previous two. Looks like this year's corporate challenge is going to be just as hard fought as 2011.