And unfortunately the results weren't as great as hoped But then again the first tests on a prototype don't always work out but it did provide enough data that I reckon that the concept could be made to work with some modifications/if planned ahead for a future build. Though given I was nursing an elbow injury (from an emergency roadside car repair thanks to debris getting wrapped around wheel axle whilst getting parts for the prototype mod, not from actual work on it) to get the test done it was a shame working through the pain didn't pay off more.
Even before the test first thing learnt was that I should have got a plastic sheet of half the thickness, much thicker than needed and proved to be much weightier than expected.
After preliminary safety checks for the first test I jumped in the tank to see how four pies did (Link to new CD/Trans WAM pics from that here, warning pie hits were very crappy: https://umd.net/profile/i/thestickytrickster/section/photos/album/pie-slide-prototype-test) and generally speaking the pies overshot their target. Furthermore as suspected the pie slide needs to be raised up a little further/smaller chair found to allow more time for the pies to twist/spin forwards whilst falling.
Afterwards I scooped up some pie from the floor onto a pie crust for a final makeshift pie to get a side angle test from releasing a pie 3/4s of the way along the slide rather than the full length and without anyone in the tank to see/track its entire path. (Link to that album with no CD WAM here: https://umd.net/profile/i/thestickytrickster/section/photos/album/pie-slide-prototype-side-test). Given the angle the pie crashes into the chair and the splattage it gets there looks like there is promise in a modified version of the concept, the fifth picture (when sorted by captions shows the pie roughly when it is face height for someone sat in that chair) whilst the sixth picture a couple frames later the pie is in probably in a decent enough angle for a good pie hit from this device. As such I reckon the following could make the concept work:
a). Reducing thickness of plastic pie slide to reduce weight.
b). Reducing length of plastic pie slide. This would have two benefits: 1 the pie would start free falling from a higher point so will have more time to spin into optimal pie angle and 2 release the pie a little further away from the occupant to bring point of impact forward and hopefully eliminate overshoot.
c). If the reduction in pie slide length isn't sufficient for both of those points itself then it may be required to increase the height of the tank (which honestly would likely require a rebuild to widen it for stability reasons so if this is necessary I will instead incorporate pie slide into plans for a future tank design rather than much around further with this prototype/mobile tank design).
Given the elbow will be probably awhile before seeing if the first two points might solve the overshooting problem themselves. That and before then I'm going to be looking to improve the gunge tank's release valve as the sealant to waterproof it looks to be degrading the adhesive holding the valve in. But in case anyone wants to take the concept and run with it themselves I present these finds to assist anyone looking to create something similar.
NB. As my previous gunge tank build posts have resulted in a number of DMs I though it best to say please be patient waiting for any replies to messages you do send off. The arm/elbow injury is impacting typing/sending messages so shan't be as quick to respond, that and I'm taking a few days to consider my future activity/how much time I spend within the WAM community versus moving on to other projects/exploring other kinks so might not be online as much.