MAC's 2nd build


#102

I may try that filter idea. The pick up hose just dangles inside the motor pod. There might be room. My new pump does slightly out perform the one I took apart. It might be the stuff that was in it was causing the difference.


#103

Mat,
I recall you took some data with your eagle tree data logger. Did you have trouble with the RPM’s jumping around, like double, like it did not know how to interpret the rpm signal.


#104

yes, i posted screenshot of the recordings on my build thread.
it’s oscillating a bit like around +/- 7 or 8%, but not that much…

double might be a wire not connected properly may be…
i think they have several kind of sensors, mine is the Brushless Motor RPM Sensor V2
i connected it on 2 of the motor phase wires…


#105

I have the same RPM sensor, the output is very erratic when running in my test tank. Sometimes it right on, sometimes off the chart.


#106

Today I cut a hole in the ice and did a in water test. Well it felt like ice. I had a shorty wet suit on. I just rode around on my belly. I did not want to fall in the water.
I running with the 12S Lipos because I have not finished the new 18650 batteries yet. It ran really good. Observations.
This board is harder to get on than my old board. It is slippery to grab. Its wider so it is harder to reach over to grab the edge. It does not extend 2 feet aft of the mast like my old board, so you worry about your feet dangling in the prop. I need to install some hand holds to make climbing on easier.


#107

My safety relay sometimes sticks ON, It did this on my last build occasionally. Now it seems to be permanently ON. I have a new spare. I think it is caused by my lack of a Anti-spark circuit. The relay gets sparked every time. So I am wondering if there is a simple circuit that would apply a ground to the ESC anti-spark lead about 1 second before the relay closes and supplies (In my case ground to the ESC).


#108

may be check how your wires are ran, the are very thin and might be sensible to interference from the big power wires next to them. If i remember right, the wire from the motor phase to the module need to be as short as possible, if you need extension, it’s better to extend the signal wire from the recorder to the module, and may be put a ferrite thingy in there too.

and regarding the hand hold, that’s kind of a must … and it makes carrying the board easier, especially when you have to walk for a while if you forgot to come back to your starting point before you battery died :innocent:


#109

I originally solder the rpm sensor on to the ESC where the phase wires exit the ESC. I have tried just two wires, one wire, and swamping to the other phase wire. Relocating the wires. Fortunately it seems to work better when I do a real water test. I have bigger fish to fry right now.

I bought a pair of these handles.If I like them I may add a second pair on the board.

image


#110

Another observation is I like the new Maytech control I bought, It is much easier to make fine speed adjustments with than my old control I was using.
But after a couple minutes holding the trigger at exactly the same position it would be nice to have the cruse control feature that came out after I bought mine. I am considering taking advantage of the Mayech Sale that is coming up.


#111

Big news. I applied for a hull ID. Eventually a Sheriff came to my house and verified that I was not just trying to register a stolen boat. He gave me a Hull ID number to stamp into my transom. I went to the Department of Motor Vehicles (DMV) and registered my E-foil. As soon as I put my registration numbers/sticker on my board I will be legal, I think.


#112

I looked at a bunch of similar pumps on eBay. Seems like many are not rated for continuous operation. Might want to run it on the bench a while and see how hot it gets. Build looks great, Good luck!


#113

It never occurred to me that I’d need to get a Hull ID, so I checked the Washington State requirements and I think I fall under this exception:

Vessels less than 16 feet long with a motor of 10 horsepower or less, if used on non-federal waters only.

Still, it would be kind of fun to have one :slight_smile:


#114

Its the wild west out where you cowboys are from. Here in New York we have laws against everything, rules and lots of tax’s and fees. In New York: If you use a motor (electric or fuel-driven), regardless of the size of your boat or the motor, you must register your boat.
10 horse power, that is just crazy talk.


#115

Received the on/off switch. Tried it today and it seems that my cheap winning remote (which has 2 channels) does work with it. Quite annoying. THe on/off switch is working, I tried it with channel 1, the trigger. But the channel 2 switch is not working of this remote, grrrr.


#116

I was testing the E-foil in my test tank. Running it hard up over 100 Amps. Then it made a strange noise like it was much slower and jerky. Long story short, I burned it up. Its a dry pod out runner.83100. I had a little bit of mineral oil in it to help it cool, obviously no where near enough. I am not ready to give up on the dry pod idea yet. I am strongly considering the direct water cooling approach.


#117

How long did it handle that current for?


#118

I’m not really sure. A couple minutes. Now looking back there were signs that I was pushing it too hard for a couple weeks. After I did my water test 2 weeks ago I took it out of the water. The heat inside caused the Internal pressure to built up inside my pod and pushed the pod apart until my mineral oil spilled out. I think I had 20ml of mineral oil inside.
Last night when I burned it up. I held it at full speed in my tank. That is a static load, that is probably worse that a real in water moving forward test.


#119

Correction. I said 83100 in one of my posts above. I meant 80100.


#120

Thanks for the reply. My new project will use a 8072 outrunner in an enclosed space, so im really interested in how much heat they generate. Im only going to put 50 amps into it for 10-20 seconds at a time. Question is weather im going to have to cool it somehow. Maybe a watercooled mounting block. what do you think?


#121

I don’t know. I think It will need a little something extra to keep it cooler. I say this because my motor mount is made of aluminum, which is connected to the aluminum pod. the metal surfaces have therm grease between them. I think the motor windings are getting the most hot on the side closest to the prop. As i learn more I will report back. I will be limiting the Amps on my next attempt.