Okie-Dokie. Servos came in the mail yesterday and I installed them last night. I'm now RTF. If it weren't for family committments this morning would have been excellent for a maiden. There's a city reservoir nearby that offers the best shot at a ROW. All of our water source reservoirs have signs posted prohibiting fishing, boating, swimming, skiing, loitering--essentially no recreation of any kind, but this one allows fishing from shore. I wrote to the city Water Division to ask to I could fly off that particular pond and they never got back to me...

I take that as a "yes".

Might be a few days though looking at the weather for the rest of the weekend.

kendall

Just in case I'm not just talking to myself here...

I was contemplating an alternative method for mounting the ESC. Right now I'm using a Phoenix ICE 75 until my ICE 100 comes back in stock. The ICE controllers are pretty well sealed up--not watertight certainly, but they've got a nice full case and heatsink on them.

What if I were to find somewhere on the top of the fuse to cut a perfect sized hole and mount the ESC half in and half out of the fuse? I'd fix it up so that the heatsink fins were just into the airstream then seal it in with silicone. Too risky?

kendall

Originally Posted by tuppertn

Just in case I'm not just talking to myself here...

I was contemplating an alternative method for mounting the ESC. Right now I'm using a Phoenix ICE 75 until my ICE 100 comes back in stock. The ICE controllers are pretty well sealed up--not watertight certainly, but they've got a nice full case and heatsink on them.

What if I were to find somewhere on the top of the fuse to cut a perfect sized hole and mount the ESC half in and half out of the fuse? I'd fix it up so that the heatsink fins were just into the airstream then seal it in with silicone. Too risky?

kendall

Hi Kendall- I can't remember where I read it but one Neptune owner put the ESC in the engine pod where the fuel tank sits. He cut some holes in the pod for cooling- I found it ! It was in a thread by tailgunner and he states-"I used a Tower Pro 3520-7 brushless outrunner (with 14x7 prop) which I reckon is one of the best value .46 size electric motors on the market. I attached it, with the help of an aluminium mount I bought on line and hacked it up to a size that would fit in that cowling. I drilled some extra holes in the ply firewall and enlarged the hole in the front of the cowl. Also I cut a bit away on the bottom of the cowl near the pylon, which I will make a small air scoop to go over, and I cut a hole in the rear. All this seems to keep the motor and ESC nice and cool."
Harold

http://www.rcgroups.com/forums/searc...20maiden%20day

I remember seeing that. I thought about it but I'd prefer to keep the wire extensions on the motor side of the ESC rather than the battery side. I'll be up in the kW+ power range and it's just less complicated to do it safely. I'm fairly confident that the Phoenix ICE could be sealed appropriately. Combine that with a good dunk in CorrosionX and I'm almost conviced to give it a try. It's hard to find somewhere inconspicuous to mount it though.

kendall

EDIT: Here's another thought--I found a 5v ESC cooling fan that plugs directly into the receiver. It's designed for use in RC cars. According to the spec sheet it only weights 6g and draws 0.16A. It comes as part of an ESC cooling kit all for $15. Eventually it would lose efficiency as the air inside the fuse warmed up, but at least it would keep the air moving. Any thoughts?

EDIT again: Now that I think about it I've got an old PC sitting in the closet upstairs. I wonder if the CPU cooling fan could be modded to fit the bill...Hmmmmm...

The computer fan idea could work. I yanked the cooling fan off the old computer's CPU heat sink. It's a 12V fan but whaddya know there's a wee brushless booger in there. I tested it on a 3s lipo and it spins up just fine and makes a nice little breeze. It's a bit biggish at 50mm and weighs 0.8oz (22g). Current draw is 150mA. The smallest 3s lipos I have are some 800mAh and they're 2oz. So, assuming I can put this together, my cooling system will add about 3oz to my AUW and cost $0. Or I can spend the $15 for a smaller unit that plugs right into the receiver.

Not giving up on my external mounting idea I came up with a third option. I could get the Phoenix ICE Lite 100 (shrink wrapped version, no case, no heat sink) and attach my own long-finned heat sink. Something with fins long enough to protrude outside the fuse while keeping the ESC completely inside.

Gonna get one of these ideas implemented before I maiden.

kendall

I'm indecisive...at least, I think I am. Maybe not. But probably.

I just bought some capacitors for the ESC to battery leads. I always thought it was a big deal to correct for battery lead lengthening, but it turns out it's really not based on my reading in the Power Systems forum. So my best solution is probably going to be to add the capacitors, extend the battery leads and put the ESC up in the pod with an air scoop and exit vent. That should let me drop down to an ICE 75 too.

Now I'm done.

Maybe.

kendall

Kendall-don't forget to show us your pics before you maiden! Did you corrosion X everything already? Unfortunately for us all our waterways have ice on them so I have all winter to get to mine-good luck and take a vid of your maiden if you can-Harold

Fly off the snow.

kendall

Originally Posted by tuppertn

Fly off the snow.

kendall

Its already too cold for my fingers and no snow yet! Actually a week ago I went and flew my Kadet at the field- I wore thin gloves-what a mistake! I was really glad to get her down in 1 piece. With gloves on you lose your sense of feel on the sticks. Maybe I'll get a transmitter mitt someday- but for now I'll go fly indoors-its great fun!

I've been screwing around the last several days not getting much done. After it was all ready to go I decided I didn't like my solder welds--10AWG to a Deans plug has always been a challenge for me. I decided I was fed up with it and resolved to switch over to EC5 connectors. None of the LHS's carry EC5's (lots of EC3's, no 5's) so I've been waiting to add them to my next online order.

In the mean time I added a vent/scoop to the pod for the ESC. I'm not so worried about it getting wet up there in the pod. Between it's OEM case and a dose of CorrosionX I think it's reasonably well protected from light spray. Of course, if I dunk the plane it going to get wet anyway, but que será será .

I looked at Home Depot for some paint for the pod and found that Behr's Atomic Tangerine is a perfect match for the slightly-darker-than-cub-yellow covering. The paint dude said it was self priming and would stick to plastic. I was skeptical, but I tried it. And I was right. No joy. I'm going back tonight for an adhesion promoter so I can give it another go. If it still won't stick then I'll do some Krylon Fusion in blue or something.

kendall

Hey Kendal- good to know your still working on your Neptune-still waiting to start on mine! Remind me what battery setup you are going to use. I still would like to go electric but the cost is holding me back. Anyway gotta go-will keep watching for your maiden-Harold

I'm using PolyQuest 30C 4500mAh packs--one 2S and one 3s in series. Using the two batts instead of one 5S pack allows the packs to sit back through the bulkheads on either side of the pylon. Right now I have room to slide the batts fore and aft enough to move the CG about 1" in either direction from the recommended location with no extra weight in the nose.

kendall

Originally Posted by tuppertn

I'm using PolyQuest 30C 4500mAh packs--one 2S and one 3s in series. Using the two batts instead of one 5S pack allows the packs to sit back through the bulkheads on either side of the pylon. Right now I have room to slide the batts fore and aft enough to move the CG about 1" in either direction from the recommended location with no extra weight in the nose.

kendall

How much flight time is that setup getting you?

Haven't flown it yet. Still putzing around putting it together.

Power system calculations are: 53A, ~990W, 154oz thrust, 65mph pitch speed. If I stayed WOT the whole time I'd get just over 5 minutes, but I suspect it'll fly very nicely at 1/2 throttle or less. I expect 12 minutes won't be a problem.

kendall

My EC5 connectors finally arrived yesterday and I now have everything soldered up. The initial spin up down in the basement blew all my foamies off their wall rack from across the room!

Ready to maiden at the first sign of reasonably calm air.

kendall