Duane's Fighter VTOL 4+1 Build Questions and Notes

ddegn · June 19, 2021, 9:14pm

I’ve been reading with interest the Fighter VTOL 4+1 thread.
After seeing the crazy high shipping prices to purchase this aircraft from AliExpress, I decided I’d but it from Banggood even though the price was higher than I saw mentioned in the other thread.

A want to extend a big thank you to @GregCovey for all the information he included in the other thread.

I decided to build the 12S version in hopes it will be easier to sell once completed (I don’t know if I’ll try to sell it or not).
Here’s a list of the parts I plan to use:

MFE Fighter 2430mm Wingspan Compound Wing EPO VTOL (Banggood $775.12 (ouch)

Vertical Lift Motors MIAT 5015 170KV Brushless Motor 12S (AliExpress) Four motors shipped $258.56.

12S 80A ESCs (MFE’s AliExpress Store) Five ESCs shipped $165.41.

Forward Flight Propeller APC 2013 (plus a spare) (https://www.aliexpress.com/item/10000248222607.html) Two propellers shipped $87.50.

Vertical Lift Propellers (MFE’s AliExpress Store) Two pair shipped $91.74.

I don’t have a forward flight motor yet. I attempted to purchase this motor but the shipping company MFE uses won’t ship magnetic items.

I’m not sure which flight controller to use. I have a Matek H743-WING which I think will be able to handle the controls of this aircraft but I see a lot of people using the Cube Orange to control this type of aircraft.

I’m sure I’ll have a lot of questions but for now I have two:
1. What’s a good option for a 12S forward flight motor?
2. Is the Matek H743-WING an adequate flight controller for this project? Are there other flight controllers I should be considering?

Please feel free to say “You’re doing it wrong!” Those are often the type of forum posts where I learn the most.

I hope it’s OK I started this new thread. The main thread about this type of aircraft is pretty long and it’s getting hard to find information in it. I also don’t want people to confuse posts I make with the great instructions in the other thread. In case it’s not obvious to everyone, I don’t know what I’m doing. I’m very very new to ArduPilot. (I’m not new to RC aircraft.)

If it’s kosher with the moderators, I’ll use this thread to ask questions and post updates on my progress.

GregCovey · June 19, 2021, 10:43pm

Hi Duane,

Creating your own thread is perfectly fine.

5020-kv210 Brushless Motor
T-motor AT4120 Long Shaft 250kv (from Christian_H on main thread)

Yes, it has plenty of pwm outputs for a quadplane application.

If you are flying commercially or in adverse temperatures then consider a Tier-1 flight controller like the Orange Cube.

Good luck!

ddegn · June 19, 2021, 11:35pm

I tried to purchase that motor.
I received the following messages from MFE:

I just ordered the T-motor you suggested. Thank you.

I’ll likely try to get the aircraft flying with the H743-WING controller.

Thank you for your help and thanks for all the great info you provided in the other thread.

GregCovey · June 20, 2021, 11:51am

Duane,

I suspect the customs restrictions are still in effect on shipping electronics and motors. It looks like Christian_H did a change on his forward flight motor later in the thread.

I am using an AXI 4120/18 (515kv) on my 6s setup. I think either one will work fine since the 4120 works well for me.

ddegn · June 20, 2021, 4:53pm

I’ll read more in the other thread to learn more. I have a other large brushless motors but I’m not sure if they can handle the 12S voltage.
I have a reasonably good technical background but a lot of the kv and prop selection stuff still seems like black magic to me. I’m glad there are so many people willing to help me make sense of all these things.

GregCovey · June 20, 2021, 5:06pm

It’s nice that MFE specified power systems for either 12s or 6s. However, you can simply use those as starting points depending upon your goals. For example, do you really need the range or efficiency of a 12s system? Can a lower cost 6s system meet your needs? Do you really need the quality of a T-motor or redundancy of an Orange Cube?

It is up to each person to set their goals within their budget.

ddegn · June 20, 2021, 5:06pm

I just checked messages in AliExpress and found this message.

Apparently the problem is caused by the pandemic not customs. I think it’s odd they say not to place an order but the only way to get this information is after placing an order.

makeflyeasy · June 21, 2021, 1:53am

I’m very sorry, due to the epidemic, banggood’s EMS is restricted. We currently only support air freight, but the freight is very high.
If you purchase a lot of things in China, you can contract a container, and we can send you to the designated warehouse in China, so the freight cost is very low.
You can also buy from our Chinese distributors.
https://www.aliexpress.com/item/4001113285374.html?spm=2114.12010615.8148356.4.48e326cfmdSaD0

GregCovey · June 21, 2021, 11:19am

This is a good deal using the AliExpress link above. The Fighter VTOL Kit is $697 with free shipping using the AliExpress Standard Shipping.

ddegn · June 21, 2021, 2:14pm

Something to consider with whether to purchase it through AliExpress of Banggood is the Banggood warehouse is in the USA. I ordered mine from Banggod and it arrived three days later. I paid more than the AliExpress price but I think I received it a lot faster.

I’m also a bit warry of purchasing from the UUUDrone Store. @teccs didn’t have a good experience using the store.

Banggood still has 7 according to their website.

GregCovey · June 21, 2021, 3:45pm

I agree. In the U.S., we have the Banggood option for only $3 shipping. Hopefully, in other parts of the world, the AliExpress Standard Shipping is still free.

ddegn · June 22, 2021, 1:24am

I was able to purchase a Fighter VTOL from Banggood. The shipping only took three days.

I’m a bit concerned about ailerons on my airplane kit. Based on how nicely everything was made, I think the ailerons where supposed to be shipped attached to the wings.
Here are some photos of the wings and ailerons.

I’m curious if @GregCovey or others who purchased this kit had ailerons which were still attached.

A less important issue is the white film. The corners of this film arrived with some slight damage.

The aileron damage is disappointing but I can certainly continue with the build. Is this sort of damage normal or is it something I should complain about? Of course I’m already complaining about it but should I contact Banggood and request replacement parts? I don’t think I’d be as annoyed if I hadn’t spent as much as I had on this kit ($775.12 including shipping and tax).

makeflyeasy · June 22, 2021, 1:49am

The problem of aileron breakage is also partly due to the design. The joint is too thin and easy to break. I have already given technical feedback, and I will improve it in the next batch.
You can use foam glue to link the sections, and the hinges inside the accessories can play a strengthening role.
The Fighter VTOL assembly tutorial is being translated into English, you can try to see if you can watch it normally.

ddegn · June 22, 2021, 1:58am

OK sounds good to me. I don’t think it will cause a problem.
Thanks for the reply sharing the video link.

GregCovey · June 22, 2021, 11:51am

Duane,

It does look like shipping damage but the black aileron hinges are the main strength of the hinge so you don’t even need to reconnect the foam, if you want. Alternatively, you can use a small amount of Foam-Tac to reconnect the hinge area and then make sure it flexes properly before mounting the black hinges.

Many people complain that the foam hinges break over time so the black hinges provide a better solution without additional force on the servo.

The ends of the white film get trimmed off so you won’t even use the bent part of the ends.

ddegn · June 22, 2021, 3:13pm

I’ve watched enough of ArxangelRC’s videos to know the foam usually ends up cracking but I wanted to be the one to cause it to crack. I think complaining about it here was enough to get the disappointment out of my system. It was nice of @makeflyeasy to acknowledge the issue.

It’s good to know the foam itself wasn’t the main hinge mechanism. I know foam hinges should be strengthened and it’s good to see the kit provides stronger hinges.

Thanks for the suggestion of Foam-Tac. I don’t think I’ve used that glue before. I’ll make sure and find all your glue recommendations in the other thread.

That’s great to hear. I’m glad I don’t need to worry about wrinkled edges.

Thank you for letting me know this info. It makes me feel a lot better about this build knowing there’s so much help available on this forum.

Christian_H · June 22, 2021, 11:59pm

@ddegn The T-motor 4120 kV250 should work great for the 12S stock configuration. I believe it is the closest in 12S spec to the stock MFE motor. The reason I bumped up to the 4130 kV230 was for a little bit more wiggle room in thrust since my MTOW is near maximum.

Just make sure you use the correct motor matched to the correct power supply (6S or 12S) as they are not interchangeable. T-Motor bench test charts recommend props based on the motor specs and the pitch will vary based on motor speed. It’s a bit of a rabbit hole looking at all the pairings/options so I would pay closest attention to what the thrust produced is relative to Amps and throttle.

Cheers,
Christian

ddegn · June 23, 2021, 1:43am

I made sure I purchased 12S motors and ESCs. I’m presently planning on using the same ESC for all 5 motors. Does the forward drive motor need a different ESC?

I like to think I have a pretty good technical background but motor and propeller selection still seems like a black art to me.

I actually have a thrust stand somewhere in my basement. At some point in the past, I planned on testing motor and propeller combination on the thrust stand. I just have too many other competing projects which keep me too busy to use the thrust stand. I finally resorted to my usual method of dealing with too many projects. I started another project.

rollys · June 23, 2021, 12:12pm

Personally, I prefer using Blenderm or even regular packing tape. Even if there’s a mechanical hinge attaching the aileron. Sealing the hinge gap improves its aerodynamic effect.

Good luck.

Christian_H · June 23, 2021, 4:26pm

Duane, so I specifically asked about ESC/motor pairings and a T-Motor representative recommended the AT 115A UBEC to me for my forward flight motor. I suspect this had more to do with what T-Motor had available rather than 3rd party ESCs that would fit the specifications. The VTOL motors also had a specific type of ESC that was recommended (FLAME 60A HV and not the ALPHA series). I have not played with enough different combinations of motors/ESCs so I can’t comment specifically on compatibility between brands. I know there is overlap based on other builds from other pilots.

I like to think I have a pretty good technical background but motor and propeller selection still seems like a black art to me.

Same. There is a significant element of personal preference here once you sort out the basic physics. For practicality, you want to pair a prop and motor that will be the most efficient for the type of flying that you plan to do.

I actually have a thrust stand somewhere in my basement. At some point in the past, I planned on testing motor and propeller combination on the thrust stand. I just have too many other competing projects which keep me too busy to use the thrust stand. I finally resorted to my usual method of dealing with too many projects. I started another project.

I promise you are not alone in this regard

Cheers,
Christian