Jump design

[mole2k]

Well basically im planning to build a few new jumps for my club as the current ones we have are a bit boring and easy to jump.

My idea is initially to build a tabletop that can be fairly easily stored away. We have the entire bottom of a stage to store stuff so as long as it can be packed relatively flat and slid in its no problem.

Dimentions is the main part of my query. For a tabletop what do people feel it should be in width/length and height for the tabletop bit and what sort of angle on the ramps. I have some plans drawn up for what the general idea I have in my mind is that it splits in two so that it folds to half width and full length then the legs also fold down. Ideally I would like it modular so I can have a straight table top or have the up and down ramp at 90 degree's to each other.

Im more concerned with what angle to have the ramps so they arnt too steep to cause the car to bottom out and bounce off the jump upsetting its flight or too shallow so you dont really get any airtime from it.

A picture of my concept for the tabletop


I'd just really like any pointers as to problems anybody else has encountered or any design adjustments you think would improve it.

[craigosh]

Size all depends on how big your track is and how big you want the jump to be. But for angle of the transition, 25-40degrees is usually good, but towards 40 your best trying to 'curve' out the bottom to smooth the entry to the transition. You can either bend the wood for this or add a short shallow section to the bottom!

I'd say go for the width of your track for the width of the jump then that again for the length of each section so 2mx2m each part then the height is however high it needs to be to get say 30degrees.

[Chrislong]

At worksop, we use some flexible ply which we just tape to the bottom of the ramp to smooth them out. They do break as marshalls stand on them, so it means next time, we just tape unbrocken ones to it.

I like your design though, don't go copying what another club has - having something that works and is different is far better. I personally like the idea of shallow 20-30 degree long up and downramps, so the cars don't get launched, they'll just skim over the top of the table top (no more than 10-12inches?) and then come down the downramp. It'll be very easy but a nice feature. Having it as a corner table top would be even better.

Make it strong enough to stand on, as marshalls WILL.

Chris

[bbq]

We have alot of jumps on oure indoor track and we use alot of loose parts so they are
eazy to take apart and to put them up.
We use soda trays (dont know if you call it that) to build jumps. they are fast to put up
and to take away. you just need loose boards.
To make a jump realy good we have a code. make the angles edges smooth on the take
of and landing and always make the landing angle longer then the take off for smoother
landings.

[Teddy truman]

looks mint! i like the single, double by the wall on the top picture! looks really nice to drive! like the doubles that you have to hit the downside before a turn! you guys really know how to build a nice track!

[JCJC]

Soda trays, we might call em milk crates. Like the large crossover in the second pic, how do you marshal that !