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green car DIARY autumn term 04


17 December 2004

Crag Rat 2
The paint has arrived this week, and we are trying to get the bodyshell rubbed down ready to actually paint. We are still not quite show of the design we are going to use yet but we do have some ideas. We have been asked to display the car at Venture Fest in York on February the 2nd. I am not sure that all the winter work will be completed in time for this, especially the clutch and wiring. Hopefully the bodyshell will be ready and we will have something to display!The clutch may be a real headache for us and David at Hayley is trying to source us a bigger roller bearing to give us more space for machining. More news about this if it happens!

Crag Rat 3
All the parts ordered over the last month have arrived. We are now working out how much aluminium we need, and this will be ordered after Xmas. We are essentially using the same frame design as CR2 but with modifications for the extra features we are considering. Building will start as soon after Xmas as possible! What batteries to we use, now that is a problem!
General
I am really surprised at the difference in help we get from various companies! I am trying to get some information on stepper motors and control at the moment, and although I have sent loads of emails nobody has bothered answering yet. I am not asking for free gifts or sponsorship just some information! On the other hand, companies like Claro Precision Engineering, Hayley Northern, Hel Performance, Ermax UK, Carsten at our secret European manufacturer! cannot do enough for us!
I would like to think that companies would be prepared to help schools, even if it is only because it us that are supplying future employees! We use Greenpower to provide students not only with a challenge but to promote interest in engineering, electronics, traditional manufacturing, and design. All surely of interest to companies in these fields!

16 September - 10 December 2004

Crag Rat 2

We had a long hard look at the problems that we had a Croft. Although we felt that we were going along the right lines, it was obvious that we still had problems to overcome! The overheating motor was probably our biggest headache. Conditions on the day were definitely not perfect but they were the same for everybody. We have bought a clutch which hopefully will help take away the shock of starting and give the motor an easier time. We have also bought a 1.5l washer bottle and pump which will squirt water over the motor. Mr. Wells has designed a circuit for us that will automatically spray at controlled times. This has been etched and is getting assembled and soldered by Tom H at the moment.
The above will all help cool the motor but our biggest problem is gearing. We have made the major decision to get rid of chain drive and convert to a V belt instead. Sprockets are impractical for us to design and make in school. The process is very complicated and because of how the car was designed with an axle, changing the rear sprocket is very hard. One tooth more or less on the front makes a big difference to the ratio and the perfect gearing may be in the middle of one of these ratios. Sprockets are also massively expensive!! With V belt pulleys, we can make them in school very easily and so get the ratio smack on. We are now converting the clutch to fit a pulley.
Crag Rat 2 was originally fitted with frictionless Glacier bearings and although they seemed to allow the axle to spin freely on the bench, we think that under load they were not so good. We have now made new bearing blocks and have fitted ball races. We have also converted the front wheels from frictionless bearings to ball races. We have been extremely lucky in finding a supplier who has donated the bearings (amongst other things!). Thank you David at Hayley Northern!
We are also changing the body shell colour scheme from the original FPR inspired one to a new one. The paint is ordered and we are busy rubbing down the shell ready for repainting. More news soon about this!
We have also fitted a front roll bar as advised by Barry Shears at Croft. We (I!) have drilled the brake disk for lightness, (much to Mr. Marriot’s disgust!)
We are rewiring the entire vehicle and all the old wiring has been removed. We are now waiting for some parts needed so we can rewire soon.

Crag Rat 2
Crag Rat 2
Crag Rat 2
Crag Rat 2

Crag Rat 3
We have not started work on CR3 yet because we are concentrating on CR2 at the moment. However we are ordering parts. After lengthy negotiations with a European company we have ordered and paid for a special part and are awaiting delivery. I do not want to say too much at the moment about this but look out for news here later!

General
We are always looking for money and have had some good news lately. A raffle in school raised just under £400 Two of the main prizes were donated back by Miss Cooke and Mr. Wilson and now a pair of signed knee sliders and a signed FPR cap are currently on sale on E Bay. We have also had a donation of £50 from an anonymous parent and the schools PTA have also donated £200. We also hope to make an announcement about a major sponsor soon. Watch this space! If anyone would also like to help these projects, please contact Mr. Hutchinson at school.
We have had a big think about the batteries we are using and have considered changing to the larger type 096. Expense, the weight and the major modifications we would need to CR2 have put us off changing. However the first fifteen cars in the final all used 096 batteries and I think changes to the rules will need to be made to allow four sets of type 028 batteries instead of three to allow teams using 028 batteries to be competitive again!

If you have any questions, comments or would like to make us an offer for a load of 3/8” pitch chain and sprockets! I can be contacted at kjsgreencar@yahoo.co.uk . Happy Xmas. See you soon!


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