Scrap trimmings + Boredom + hot glue = tiny jet?

[JennyC6]

Built entirely from the scrap trimmings that my Spear build left behind, just thrown together in a way that looks cool. Main spar is some scrap control rod trimmed to length and fit into notches cut in the wings. Ailerons, elevators, rudder cut and bevelled. Might try weighting the nose and chucking it down the hallway, see if itt'l glide decently, but I really mostly just built it to practice putting foamboard planes together and put to use some of the scrap foamboard left behind from my Spear.

If I did try to fly it, I'd probably use some 2g linear servos on it, but I'm not sure about power. I wonder if they make EDFs this small...

 

[FastCrash45]

I think I saw a 30mm edf at towerhobbies. I've looked at so much stuff lately I can't remember. It was for their UMX series of micro planes like their A-10

 

[FastCrash45]

Here's the link it's actually 28mm
https://www.towerhobbies.com/cgi-bin/wti0001p?&I=LXHPBC&P=Z

 

[JennyC6]

Yeah that's the one I'm looking at using. Gonna throw the 13,500kV motor in it, naturally. But Horizon doesn't specify what sort of current draw that thing pulls so I have no idea what ESC to use. I have a plane ESC on hand but it's a big ol' honkin' 40a and that's a bit overkill for a 15.5" span microjet, yanno?

 

[FastCrash45]

Yeah that's the one I'm looking at using. Gonna throw the 13,500kV motor in it, naturally. But Horizon doesn't specify what sort of current draw that thing pulls so I have no idea what ESC to use. I have a plane ESC on hand but it's a big ol' honkin' 40a and that's a bit overkill for a 15.5" span microjet, yanno?

Seems like a 12amp would be more than enough.

 

[JennyC6]

Seems like a 12amp would be more than enough.

https://www.amazon.com/dp/B07K18DJG5/?tag=lstir-20

I'm planning on buying these for power. If it flies okay on 2s I'd have four packs on hand, if 2s isn't enough thrust I can always series two packs for 4s at the ESC and still have two flights before I'm headed to the charger.

IIRC the EDF I want to use is normally used in the UMX ultra-micro MiG 15, which IIRC, runs on 2s.

 

[FastCrash45]

https://www.amazon.com/dp/B07K18DJG5/?tag=lstir-20

I'm planning on buying these for power. If it flies okay on 2s I'd have four packs on hand, if 2s isn't enough thrust I can always series two packs for 4s at the ESC and still have two flights before I'm headed to the charger.

IIRC the EDF I want to use is normally used in the UMX ultra-micro MiG 15, which IIRC, runs on 2s.

That's a good deal. I had to put those in my wish list.

 

[JennyC6]

Mmm. When I went looking for batteries I kinda went down the oddball route due to the shape of the fuse. I'm not entirely sure I could get a normally sized pack of similar mAh in there and leave enough room for the EDF to breath.

 

[Vimana89]

Definitely interested to see how this turns out. Once I get better at building and flying I'd really like to try some micro stuff, especially small diameter EDF setups.

 

[JennyC6]

I have done some glide testing and the results are promising to say the least. I taped a row of pennies down the underside of the nose and it glides like an absolute dream. Fairly confident itt'l fly quite nicely as long as I keep the electronics package light enough.

 

[Vimana89]

Good luck! I'll definitely need to see what sort of electronics you used for the 28mm EDF. I really want to make a little foam board HP-115, simple FT style, with a roughly scale wing ratio but larger intake hole and stuff. I think it will scale down nicely as long as I keep it light. I may end up with like a 40mm EDF, but if possible I'd like to use the 28mm one.

 

[JennyC6]

Hah, what a goofy lookin' jet. Can't wait to see it flying in foamboard!


I shot Horizon's product support department an email asking for max current spec on the 13,500kV motor a couple days ago. Not holding my breath on a response, but given how cheap they are, I might just go with a 12a ESC and see what happens. I know EDFs are hungrier than props but I can't imagine such a small motor/duct unit is gonna pull >12 amps when the miro MiG it's intended for only comes with a 20c 280mAh battery.

It's a shame EDF efficiency plummets the smaller they get and that this 28mm unit is about as small as they can get and still be practical.

 

[JennyC6]

Update on the EDF unit: Horizon Support basically said 'no clue lol' when queried about the electrical requirements of this power unit. Guess I'll just tinker around then.

 

[Vimana89]

Update on the EDF unit: Horizon Support basically said 'no clue lol' when queried about the electrical requirements of this power unit. Guess I'll just tinker around then.

Maybe look at one of the little e flite models that use this edf and see what it uses for a battery and stuff. Maybe the ESC requirements are listed too.

 

[JennyC6]

Maybe look at one of the little e flite models that use this edf and see what it uses for a battery and stuff. Maybe the ESC requirements are listed too.

THey use it in their ultra-micro MiG 15, battery's a 20c 280mAh 2s. No ESC requirements, though, as this aircraft uses one of those AIO boards that has their AS3X gyro system, a DSMx receiver, two linear servos, ESC, BEC, and servo ports for the linear sub-2G servos that aren't on the board, all in one unit.

FWIW this plane's about the same size as the one I fabricobbled.

 

[IcedStorm777]

this looks cool, can't wait to see it fly

 

[mayan]

Seems like a 12amp would be more than enough.

That's what I would bet on. You can also try to find a 15A ESC I had a few a while back. I too can't wait to see this fly . Good luck with it.

 

[Vimana89]

If you are still on this project, good luck! I was browsing the FT store, and found this pre-soldered 12A ESC. This might fit the bill: https://store.flitetest.com/emax-blheli-series-12a-esc-xt30-emx-sc-0098/p784967 if your battery doesn't use an xt30 connector, I believe there are adapters.