Trial and Error - engineering?
I've been trying to bring this thing to life and keep painting myself into a corner. Bench testing everything is functional and responsive to controls.
Testing in the water the drive continues to be an issue. I had played with several prop configurations all had the same issue Bob had warned me of - the tapered tail will be enough of a restriction to create a back flow and it did. So to try and get around that built a jet drive a tube within the tail cone to pull in water and push it along - no taper to deal with and it helped but sucked in air so i moved the inlet to the bottom and that helped but not enough flow to get speed. The rudder servo limits how bit the jet tube can be so i abandoned that approach. So the latest approach idea - move the drive to the pinch point - the rudder ball, it the smallest diameter in the tail section. made a couple parts and assembled, dunked a whoaaaaa i've got thrust finally.... at least by itself. while changing things cut back a bit of the tail cone to ensure the outlet of the rudder ball is unobstructed at full turn. Something else this arangement should get me I didn't have before is steering in reverse. should be able to check out the new drive in a day or two with the tail cone and rudder integrated, wish me luck.
Gemini AI image
trying to explain to my son what all is involved
bench testing all the various components - shown prior version with jet drive, inlet on bottom side
rudder ball with integrated drive
I've been trying to bring this thing to life and keep painting myself into a corner. Bench testing everything is functional and responsive to controls.
Testing in the water the drive continues to be an issue. I had played with several prop configurations all had the same issue Bob had warned me of - the tapered tail will be enough of a restriction to create a back flow and it did. So to try and get around that built a jet drive a tube within the tail cone to pull in water and push it along - no taper to deal with and it helped but sucked in air so i moved the inlet to the bottom and that helped but not enough flow to get speed. The rudder servo limits how bit the jet tube can be so i abandoned that approach. So the latest approach idea - move the drive to the pinch point - the rudder ball, it the smallest diameter in the tail section. made a couple parts and assembled, dunked a whoaaaaa i've got thrust finally.... at least by itself. while changing things cut back a bit of the tail cone to ensure the outlet of the rudder ball is unobstructed at full turn. Something else this arangement should get me I didn't have before is steering in reverse. should be able to check out the new drive in a day or two with the tail cone and rudder integrated, wish me luck.
Gemini AI image
trying to explain to my son what all is involved
bench testing all the various components - shown prior version with jet drive, inlet on bottom side
rudder ball with integrated drive
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