Before we wrapped it up yesterday, we talked about how good it would be to have a 'lessons learned' thread for the car builders. There are numerous
technical challenges for the builders -- building a car that just makes it to the other end of the track is no small feat.
I also figure that while we're at it, it won't hurt to have a 'lessons learned' for the track builders. This event was filled with technical challenges. You wouldn't think that laying down some straight track would be such a difficult task, but it is. In fact, the first year they tried this in England, their competition turned into an exhibition because they were unable to get the challenges solved. There isn't an unlimited amount of time before the event to lay a track down that's over 200 feet, and do the testing that's needed. There's no collected body of experience to draw from, because so few people have actually faced these particular challenges.
Remember that you won't have a car to test with. All you can do is try one of your basic 'slow' cars, because LSR cars will have a limited life, and you can't just ask somebody to use their LSR car to see how the speed trap is working for cars at 100 mph.
1) Have two complete tool kits, one for each end of the track. The distance between track ends makes even the simplest tasks difficult. Realizing that you left a drill bit somewhere else adds a 400 foot walk when you want to switch bits.
2) Have a bicycle for retrieving drill bits.
3) Use a chalk line so that you can have a reasonable chance to lay the track straight. Even if your track is cut with sheets of MDF and your track pieces ar 8 feet long, you still have over 30 track sections, and lining them up isn't easy. The slightest wiggles make things very tricky for cars to negotiate at 100+ mph
4) You want steady power at both ends of the track. Jumpers help, but that is still a lot of wire with resistance. You'll want a power supply at each end.
5) Putting a power supply at the far end and turning the power on is great -- but it disables the driver's ability to use a controller because the rails are already live when you put the car on the track. It's necessary to electrically isolate the final part of the track from the first part of the track. This means that after a certain point, driver control is gone and the car is on full throttle cruise control. Splitting the track half way would probably be ideal for the steadiest power.
6) Jumper the track from the starting power supply out to the electrical isolation point, and from the final power supply back to the electrical isolation point.
7) There are serious limitations to the software that's available. SRM will not allow you to input a minimum lap length that takes less than 0.5 seconds. We had a trap of 8 feet on the wood track. At the official speeds we reached, the trap would have to have been 85 feet! And the faster the cars go, the longer the trap has to be. Fortunately, there is a little-known piece of software available that Dan Dyke had, called 'TrapSpeed'. Fewer limitations. Even so, the limitations meant we had to abandon the wood track, because the sensors weren't nearly far enough apart to do the job.
It's necessary to boot to DOS on a reaonably fast computer with a parallel printer port. These are getting harder to find, and won't be a problem
if and when USB support becomes available for timing systems.
9) Have a good soldering gun. That proved very useful.
There's more, but I need to get going. I will say that this was a difficult series of tasks that often came up as surprises at inopportune times. Well, the tasks themselves weren't difficult -- it was coming up with the best solution on the fly, then putting the solution in place. We had a great team of guys who could troubleshoot problems relatively quickly. Now that we've solved a bunch of these issues once, we think the next one will be MUCH easier for whoever is running it -- and there's some accumulated experience to help out.
I also figure that while we're at it, it won't hurt to have a 'lessons learned' for the track builders. This event was filled with technical challenges. You wouldn't think that laying down some straight track would be such a difficult task, but it is. In fact, the first year they tried this in England, their competition turned into an exhibition because they were unable to get the challenges solved. There isn't an unlimited amount of time before the event to lay a track down that's over 200 feet, and do the testing that's needed. There's no collected body of experience to draw from, because so few people have actually faced these particular challenges.
Remember that you won't have a car to test with. All you can do is try one of your basic 'slow' cars, because LSR cars will have a limited life, and you can't just ask somebody to use their LSR car to see how the speed trap is working for cars at 100 mph.
1) Have two complete tool kits, one for each end of the track. The distance between track ends makes even the simplest tasks difficult. Realizing that you left a drill bit somewhere else adds a 400 foot walk when you want to switch bits.
2) Have a bicycle for retrieving drill bits.
3) Use a chalk line so that you can have a reasonable chance to lay the track straight. Even if your track is cut with sheets of MDF and your track pieces ar 8 feet long, you still have over 30 track sections, and lining them up isn't easy. The slightest wiggles make things very tricky for cars to negotiate at 100+ mph
4) You want steady power at both ends of the track. Jumpers help, but that is still a lot of wire with resistance. You'll want a power supply at each end.
5) Putting a power supply at the far end and turning the power on is great -- but it disables the driver's ability to use a controller because the rails are already live when you put the car on the track. It's necessary to electrically isolate the final part of the track from the first part of the track. This means that after a certain point, driver control is gone and the car is on full throttle cruise control. Splitting the track half way would probably be ideal for the steadiest power.
6) Jumper the track from the starting power supply out to the electrical isolation point, and from the final power supply back to the electrical isolation point.
7) There are serious limitations to the software that's available. SRM will not allow you to input a minimum lap length that takes less than 0.5 seconds. We had a trap of 8 feet on the wood track. At the official speeds we reached, the trap would have to have been 85 feet! And the faster the cars go, the longer the trap has to be. Fortunately, there is a little-known piece of software available that Dan Dyke had, called 'TrapSpeed'. Fewer limitations. Even so, the limitations meant we had to abandon the wood track, because the sensors weren't nearly far enough apart to do the job.
It's necessary to boot to DOS on a reaonably fast computer with a parallel printer port. These are getting harder to find, and won't be a problem
if and when USB support becomes available for timing systems.
9) Have a good soldering gun. That proved very useful.
There's more, but I need to get going. I will say that this was a difficult series of tasks that often came up as surprises at inopportune times. Well, the tasks themselves weren't difficult -- it was coming up with the best solution on the fly, then putting the solution in place. We had a great team of guys who could troubleshoot problems relatively quickly. Now that we've solved a bunch of these issues once, we think the next one will be MUCH easier for whoever is running it -- and there's some accumulated experience to help out.
I'm also thinking that guys might have an interest in running their own event, because
it's just really, really cool. Passing along a little knowledge will make it quite a bit easier for anybody who wants to try it. It will still be a
boatload of work, but it's a lot easier when it's a series of planned tasks rather than a series of technical challenges.
)
