Hi, i wanted to share my tow boogie build, struggles, and successes so far.
Background:
I’ve been surfing for a few years, got into wingfoiling for the windy days, and started this tow boogie build for when there is no wind nearby. Needless to say i’m a newb foiler and i’m looking to progress - rapidly! The build is one of haste and convenience, if its not obvious 
State of the project:
Specs:
- Flipsky 65161 120kv motor
- Flipsky 75200 vesc
- Flipsky vx3 remote
- Rawrr mantis 72V/30Ah battery (e-dirtbike, thanks fb) (35 lbs!)
- Pelican 1500 case
- Cabrinha aluminum mast
- 10x8M-LH APC-brand propeller (most success so far)
- 3D printed motor mount which squeezes the mast
Struggles:
Board:
I began with a boogie board, but with the battery i’m packing I quickly discovered that it had nowhere near enough volume. 2nd attempt was a foam shortboard, specifically an odysea 5’0 ‘stump’ i grabbed off fb marketplace. Discovered 36 liters was enough to float but not enough foam to be stable. Finally I went nuclear and grabbed a 8’ wavestorm (fb marketplace). It has been stable but could be wider as it tends to bog a rail when turning.
Remote:
I’m on my 3rd flipsky vx3. The receiver of the first got water damaged, and the transmitter of the second got water damaged (upon disassembly i saw some wires were corroded due to poor potting). I now coat the receiver/connectors in epoxy. The transmitter I had disassembled, added epoxy over the wires around the potting, and filled generously with corrosion-x. Its only been 3 sessions with the third remote but so far so good.
Vesc:
Get the ‘Vesc Tool’ app! I have done some on-the-fly config adjustments and data logging using my iphone. It is a huge convenience.
So far with just the vesc in a pelican case, I can get ~4 mins of continuous run time before I hit the 80C mosfet temp limit i’ve set. My next build will use a watercooled vesc.
I had one incident where my wetsuit had dripped into the open pelican case unknowingly, creating time-bomb short of the receiver pins on the vesc.
When I got back in the water the boat took off with intermittent throttle leaving me behind! I had turned off the transmitter, plunged it under water, but the vesc had a mind of its own. Thankfully the boogie has a slight left steering bias and I was able to recover it ~200 yards down the dock/shoreline! Crisis averted…
Propeller:
This is the one i’m still struggling with. I’ve tried the smaller black props (~4in diam) from flipsky and found them too weak to pull me up onto foil. I’ve tried the white 7 1/4 x 5 propeller also but found it too torquey. So far the 10x8 APC-brand propeller has been working a treat but I still pull many more amps than others that i’ve read about on the forum.
Here is a plot showing the amps and motor rpm for some 1 minute laps. The idle periods are me letting the handle go and trying to pump.
I consistently pull my software-set max of 110 amps to get on foil, and pull ~90 amps when on foil. The rpm is consistently 5000-4000 rpm, much less than my 72V*120kv = ~8640 max.
I think this suggests the prop diam is too large but the pitch may be alright. It pulls just enough to ride comfortably (albeit a pit high AoA on foil) on my 250 in^2 unifoil.
Success:
Here is a video with the same setup I describe above but not the same exact session I data logged.
