We had 10 days before we were due to go to Elstree for filming and thought we had best check over Sir Chromalot and make sure 'all systems are go'.
On previous tests Sir Chromalot ran out of steam after about 3.5 mins. So it was decided that larger batteries were needed to give us a good 5 mins running time and a couple of mins. thrown in for good measure. This equation was given to the accountant at Scantruck. After only 2 days his department came up with a result of a total of 7 mins. Running time. Although us Hub Nuts fail to understand the formula, for those of you with an understanding of maths it goes like this:
5 + 2 = 7
As we now had to double the size of batteries, we feared that this would put us over the weight limit of 80kg. So Dave got busy chopping lumps off of the Robot. Steel components now had to be remade in aluminium and many trips were made to the scrap dealer for an accurate weight assessment. The Scrap man kept offering us a ten pounds for the whole lot until one day he offered £9.00 so not being stupid we knew that we had the weight about right.
…Working through the night, Again!!
After much hard work we had the new better improved batteries fitted. A spare 3 sets that now plugged in and out easily and 9 chargers that simply plugged in as well. All the motors had been heavily suppressed with capacitors and ferrite rings to make certain that we suffered no radio interference
…There's motors somewhere under that gaffa tape.
A penultimate test was needed. The Robot had never been put to a rigorous test, but we were all very confident. A mock arena was built at Smith's shooting range. Loads of heavy obstacles to push and crash into, ramps and an obstacle course was the setting. The shooting range is renowned for bad radio interference and stray signals so this would be a good test for the Aerial as we guessed it would be similar to a film studio.
On the first set of batteries we decided to just drive it around constantly to make sure it kept going for the full 7 mins. It moved about half way down the range approximately 15 mts and stopped. It had gone out of radio range. We were amazed as it was never a problem in the garden you could be 200mts away and it was fine. We set the aerial from a laying flat position and moved it to a temporary vertical one. That sorted, it drove all around the arena and handled well for a good 7 mins.
With Battery set 2 fitted, we went flat out to try and break something. We drove it hard, jumping over ramps, smashing it into backstops (1/2 thick boiler plate to stop bullets) and pushing 100kg obstacles for a lot longer than we should have. Then disaster, a wheel had become jammed solid and the motor pulled to many amps and the Robot suffered a burn out. The wheels had worn badly due to all the skidding around and the relays were acting up.
With hindsight this test should have been done months ago, NOT 5 days before filming, But we're the Hub Nuts, time for a photo?
….Steve Smith wondering how and why!!!
With 8 new wheels ordered and coming from Germany, (thanks to Rhombus Casters), another 8 new shafts despatched from Dewalt, (not forgetting to mention that they also tested to destruction 2 motors to try and find a reason for our problem), it just left Dave Whitehead sorting new and better bearings, and spare wheel hubs in readiness for the new components. Steve Smith took the relays apart and found the springs to be to weak and Iron filings in the workings which were fowling up the coil and contacts, but they handled the excessive current superbly, 70amp automotive relays are the business.
……wir bewegen vieles! RHOMBUS ROLLEN
Meanwhile, Steve Merrill replaced some of the cables with heavier ones and arranged a Photo shoot with the local papers just to keep us on our toes.
….Local Gazette interviews Team Hub Nuts
Within 4 days we had the parts fitted, had our photo in the local papers, made a new aerial, tested the Robot, (although a little gentler this time), and was as ready as we were going to be.
……………………..Dave …..… Merrill & Smith
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