October 2003

Saturday 4^th October 2003

Not much has happened since the filming of series 7, partly due to the main event of the year having now passed, and partly due to my car snapping a cam belt and needing a new clutch. The former being one of the few occasions when I wished the car didn't have a 16 valve head because swapping out and grinding 16 valves is no quick job!

For a report on how we did in series 7 and the damage we sustained, see the events section. In brief, I took an aweful lot of damage in the qualifiers, which took two long days to repair. After that, we took a much smaller amount of damage that I have still to put right.

During the post Series 7 lull I have taken the opportunity to think about improvements I can make to the pneumatics. Having spoken with people like Paul Cooper from the M2 robot, I will try to improve the speed the flipper resets. At the moment I either let the flipper return under its own weight, or I drive it closed with the full 16 bar pressure. The first method is very slow as the high pressure side of the ram has to vent a full ram full of gas through a low flow rate valve. The second method of driving the flipper closed wastes a lot of gas and reduces the number of total flips per bottle I have.

My compromise solution is to do away with the low flow rate valve, and replace it with a high flow valve supplying a 2 bar feed to the return side of the ram. Together these two feature should save on gas while driving the flipper home quicker than with gravity. With the component I have in mind to do this, I send an email off to Brady at Norgren to see whether they were still willing to sponsor me for the coming year. He responded very quickly saying he would arrange for a high flow rate valve to be despatched. Thanks Norgren for your continued support.

Today I decided to repair some of the bent chassis members I received during my round 1 battle. The ears didn't take too much hammering straight, but one of the rear spikes was quite reluctant to return to its former position. After a lot of hammer wealding the spike was pointing in the right direction again, but the member it was welded to was still quite distorted. I realised that it was too stretched to return to its former shape, so decided to cut it out altogether and weld a new piece in.

New chassis member

Old chassis member

Tuesday 6^th October 2003

I received a parcel from Norgren that was a new high flow rate 3/2 valve. I hoped to improve the flipper operation with this new valve, so I suppose I will have to knuckle down to designing the new pipework!

The pneumatics will actually be a bit simpler than before because I am going to do away with the 5/3 valve that gives me slow control of the flipper. The main reason for this is that I've never really used the slow flipper function, so I might as well get rid of the 5/3 valve and save myself some weight and unnecessary complexity.

Here is my new proposed pneumatic design.

Thursday 8^th October 2003

I thought it was about time I attempted to straighten the Hog's slightly twisted flipper, but it proved to be quit a challenge to get it back into alignment. During my Series 7 battle, Mr Phycho picked us up mainly by the flipper, and then dropped us outside the arena from six feet up. We landed heavily on the rear spikes as well as the flipper, which added a few extra bends to those already received.

I had used a fair bit of triangulation in the flipper construction to make it sturdy knowing the type of forces it was due to withstand, but now that it had been miss shapened, many of the struts were going to be ever so slightly bent or stretched. It wasn't going to be a straight forward task to straighten them all out again!

After several fruitless minutes hitting various cross members with a hammer, I came to the conclusion that it wasn't going to budge unless I cut a few struts to relieve the stresses. I of course could have simply made a new flipper, but decided it would take too long, and besides, I didn't have enough spare tubing. After a lot of careful thought and consideration, I decided to select two struts that I would catch up all the re-alignment in rather than attempting to lengthen or shorten every strut in the flipper. This might mean that the flipper will look a bit like it has a broken nose, but I will at least get the front scoop plate laying horizontally above the ground again, instead of the oblique angle it is tilting at at the moment.

I cut the two struts on the left hand side of the flipper that allowed me to bend the front scoop plate to a more or less horizontal position. I then made a couple of filler pieces to take up the gaps in the cut struts, and then welded them in. The hog now looks like it has a slightly crooked nose, but at least the scoop runs flat above the ground.

Saturday 18th October 2003

I had a go at reconfiguring the pneumatic by removing the 5/3 valve and then trying to figure out where to fit the new low pressure regulator that will feed the flipper down. I had most of the parts I needed left over from the items Norgren had given me during a visit to their returns department, but there was the odd item that fortunately had just arrived in the post from RS.

Tuesday 28th October 2003

I finished working on the new pneumatic design and had additionally moved the dump valve to a new position just inside the Hog's ear. I had a couple of attempts at routing the pneumatic pipes so that I had as few right angles as possible, and also had the flow from the regulator to the buffer tank as straight as possible too.

New 3/2 "flipper up" valve

Low pressure "flipper down" pneumatics

On the second attempt I was satisfied that I probably couldn't improve on the pipe routing.

I then turned my attention to improving the flipper hinges. At the moment the flipper was crudely secured to two box sections with a couple of bolts. There was simply a hole in the strut, which was now showing signs of being elongated, so I thought it might be a good idea to welds some metal tubes in these struts to spread the load and secure the hinge more firmly. I welded some 10mm internal diameter tube in the struts, which left me with the task of filing the welding back enough to make room for the flipper.