Hi Smitty,

Now you are on to something.     Why don't the manufacturers make a frame with adjustable arms   
NOT just different size replacement arms, but one set that can be adjusted on the frame base 

There are two reasons: weight and strength. 
Weight is the obvious reason since any extra mass whether the extra arm material or the mounting hardware adds weight.
Strength might be the other reason. Is a 1 piece frame stronger than a multi-part frame. Well, maybe; it depends.

You know, you might have just inspired me.  

Yeah, when I first built the Phantom-X, I just used a set of arms that we in the parts bin. I was looking to get a little larger prop on the GEPRC Phantom frame which I also had. When I started putting it together, I thought, why stop at 3 inch and just set them at 4 inch. I only trimmed down the extensions when I realized that this will always be a 4 inch quad and NOT a 3 inch. 

Now, here is thought     How about a universal set of arms that could be adjusted {and trimmed if you want to} that would fit on a variety {maybe any} existing frame.   

Truth be told, I am not taking credit for the idea, even the original one; 
I saw it somewhere else, but thought it to be a good idea and a workable one for my application.

I can't imagine adding THAT much weight to have the inner arm and outer arm overlap maybe 1" to allow length adjustment. 1" may be too much and would have to be figured out, but
having the arms attached to the body being slotted and then the add on arms be slotted then use 2 or 4 bolts to keep the extensions from sliding in/out and also twisting.

The flipside would be how much would it cost to just buy a separate frame and swap everything over. But having ONE drone that can be a 3" and then become a 5" would be nice. You'd just have to accept the fact you may lose performance due to adding versatility of this feature.

Simple balance of give and take.

Hi Smitty,

Check out the first post of my Phantom-4X build  <- Click Link.   

The first post includes most of the original build information, specifically the frame. I took a GEPRC Phantom frame base plate and used TomoQuads Mosquito replacement rear arms as overlays. It just worked out that these arms provide a spacing for 4 inch props while being long enough to bolt the back part of the arm to frame as well as using the motor mount location; so I used one bolt in each location. These overlay arms could be set at 5 inch and bolted to the motor mount location with 2 or 4 bolts. Although this is not a "slotted" approach, it would work. In fact alternate sets of holes might be better than slots. The arm has to move out 1/2 inch for a 1 inch increase in prop size. 

The Mosquito rear arms are wide enough to use all 4 bolts at the motor mount location of the Phantom frame.

Well, today {2021-02-04} I worked to get the electronics soldered up. Everything went very smooth, the Flywoo F411 FC stack was easy to solder, the pads are pretty good side for small pads; no problems. With the soldering done, I connected a smoke stopper and a battery...NOTHING   

I checked all solder connections; everything looks really good; clean connections, No solder bridges, nothing unusual. Now, I decided to spit the stack and start with the ESC...NOTHING     The only thing on the ESC is the motor wires and the battery wires.    All solder connections look good.    At this point, I have NO Idea what is wrong nor how to go about diagnosing the ESC.  

If I decide to buy just the ESC that will be some time later, but that likely won't happen for this upgrade. 

I have put all of the stack and parts back into its little round plastic container, marked a Red "X" on it and set it aside. BUMMER    Grrrrrrrr 

No more work on this today, I will just use another FC and move forward with the assembly. Now, she will get a whoop board with BLHeli_32.  

The Phantom-X is getting a new camera cage; Armattan Tadpole Aluminum Cam Brace.  These are spare parts that can replace a 20mm standoff column. Best I can tell they are as light as aluminum columns so a swap does not add to the weight of the craft. I also use these on the FrankenFly-2-4 quad. 

After taking an assessment of flight controllers in the parts bin, 
I have decided to use the BetaFPV Toothpick F405 AIO 20A V4 BLHeli_32.
Although others have expressed concern about BetaFPV's quality control, I am going to give it a try anyway.
By the way, this particular FC has a connector for the DJI unit, but I am not using it since I don't have any digital components.

NOTE:  I have contacted Flywoo and am trying to buy just the ESC board for that stack. 

Onward and Upward...

2021-02-16    Finally, things are coming together.

After the problems with the Flywoo 16x16 stack, I have been going a little slower and testing EVERYTHING after any soldering on the FC just to be sure; piece by piece. So, far everything has tested out OK; No issues, No problems. The electronics package is now complete and fully tested including the motor direction. Now, I am ready to assemble the Phantom-X.

The first picture is the Flight Controller with 5 V BEC connected and the R9MM with the antenna attached.

The next picture is everything piled on the scales {except props and some assorted bolts} weighs 93.1 grams. Fully assembled, I am expecting a dry weight of about 105 grams without a buzzer. 

The next 2 pictures are the GPS as mounted. The mount is nothing fancy; just a piece of strong, light weight, clear plastic from an MCT oil bottle. This mount is sort of Ghetto, not as trick as a 3D printed one, but it works for me. The GPS is then attached with clear heat shrink tubing. 

Yeah, no copper, but that can be added later should I desire to do so. 

The last picture is my wiring diagram for the BetaFPV F405 20A Flight Controller. Yeah, I used connectors rather than directly soldering the components to the FC even though it technically adds a little weight. For me, it makes swapping out components easier and often they can be changed without dismantling the quad. The Phantom-X has always been my primary experimental build so having the ability to expediently swap parts is a big plus for me. 

I like your GPS mount idea! Do you know how much it weighs? I may try something similar if I don't get decent performance with the GPS mounted on the top deck.

(16-Feb-2021, 04:55 PM)V-22 Wrote: I like your GPS mount idea! Do you know how much it weighs? I may try something similar if I don't get decent performance with the GPS mounted on the top deck.

Hi V-22,

Since I didn't weigh the plastic before mounting the GPS, I cut a new piece from the MCT Oil bottle. I cut the first piece from the back side where these was no label. I cut the "test" piece from the front of the bottle and left the label on {just so you know exactly what I am using}. Also, that label is a real pain to remove. The plastic piece weighs 1.8 grams; the weight with the clear shrink tubing is 2.4 grams. 

The particular plastic is solid enough that it does not deform when you heat shrink the tubing over it. Yet, it is somewhat flexible and I am sure it could be "bent" if the heat is high enough. I also used a strip of the plastic as a plate to secure the U.FL cable to the VTX {I will include a picture when I post the completed results of the rebuild}.

I also like the "frosted" plastic that the square alcohol bottles are made from; this plastic is a little  more pliable, but also works well. Yeah, sort of Ghetto, but I will use what ever works. Plus, I do not have a 3D printer, so I have to get creative. 

2021-07-17   The Phantom-X upgrades have been completed.   
                              The indoor hover test was successful. 

A short indoor hover test was performed which proved successful and very stable. 
The dry weight is now 108 grams without a Buzzer, however, the ESC beeps are pretty loud; maybe enough.
With a 3S 1100 mAh GNB battery strapped on, the AUW is 174.6 grams.

A 2S 18650 3000 mAh pack weighs about 100 grams so this would put the AUW at about 208-210 grams.

She is ready to fly. 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Yes, I used connectors for most of the components...and Thankfully I did, because various items were disconnected and re-connected several times while determining the best position and fit for each one.

Also, the motors can be swapped out without dismantling the quad...big plus here since I plan to change them.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The first picture shows the plastic plate which secures the U.FL antenna connector to the VTX. 

The second details the components and construction of the Phantom-X.

The third picture is just a picture, but shows the location and orientation of the antennas for the Rx receiver and the VTX.

The final picture shows the weights of the quad.

2021-02-26 The Phantom's first flight after the upgrades and rebuild.

At this point, I have not calibrated the battery nor done any tuning; Stock BetaFPV.

Overall, I was pleased with the Flight which lasted over 14 minutes with my standard 3s 1100 mAh GNB Battery.
Occasionally, there was some vibration in the craft and the video had some diagonal waves (???).

I used the battery pig tail with the capacitor already attached, but it looks much smaller than what I normally use. I will likely add my standard 1000 uF 35V capacitor to see if that clears up the video. I will fly a couple more of these packs through her to get a good baseline before making any changes except for battery calibration.

2021-02-27   Ok, I couldn't help myself.

I just had to add that 1000 uf 35 Volt capacitor. This was actually pretty easy and accomplished without dismantling the quad since I used connectors for the 5V BEC. I just added the capacitor with connectors to that junction. Although it might not be the preferred method, it does work. 

While I was looking at the frame and contemplating the props in view, I decided to try a Deadcat mod. As it turns out, this was quite easy to accomplish since the build already has arm extensions. I simply removed 1 bolt swiveled the arm and re-inserted it (after drilling a 2mm hole) on the front arms. Instant Deadcat frame. 

Since I had an arm extension bolt out anyway, I decided to use an M2 x 22mm bolt which would extend down below the arm about 15mm. Next, I cut down antenna tubes to provide a 1.5 inch rise; plenty of room to bottom sling a battery. Now, I can run 2 batteries in parallel; one on the top and one on the bottom. I am anxious to try that and see how it works.

The new dry weight with battery straps is 121.5 grams, but then I do have an extra capacitor on it.

We are ready to go again.

Clever! Are you thinking of running two GNB 3S 1100mAh in parallel? Really interested to hear how it flies and what flight time you get!

(27-Feb-2021, 11:44 PM)V-22 Wrote: Clever! Are you thinking of running two GNB 3S 1100mAh in parallel? Really interested to hear how it flies and what flight time you get!

Hi V-22,

Yes, that is the idea. Sadly, that will push the AUW to 253.5 grams...so that configuration wouldn't make the challenge. On the other hand, it is still ok with me. To keep it under the 250 gram mark, I will have to use a 3s 1100 mAh GNB and a 3s 650 mAh GNB battery...now, that will be interesting.  Having dual battery mounting positions opens up a lot of possibilities...Top only, bottom only, or both at the same time. 

If I wanted to break it down again, I would remove the small capacitor on the pigtail and maybe even swap the 1000 uf 35V cap for a lighter weight one. I have some light weight 470 uf 35V caps that I could try. Yeah, I could remove the landing gear, too. So, I can probably tweak the weight some...just for the challenge...we will see. 

On the positive side, I am refining how I want to build the Quest250-LR, but I think the dual battery mounting will be included. I like being able to split the batteries.

What do you think of my "deadcat" mod?   I am anxious to see how it flies.

I'm not sure if you can mix capacities like that and wire them in parallel... With a slow enough discharge it might not matter, but I think you'll run the smaller pack dry too fast and damage it if you try to discharge past twice the smaller packs capacity.
Edit: Nevermind, this isn't a problem. Just need to make sure both packs are at the same voltage before connecting them.

Interested to see how the deadcat mod flies! Have you checked the blackbox logs with your arm extensions to see if there are any low frequency vibrations?

(28-Feb-2021, 07:19 AM)V-22 Wrote: I'm not sure if you can mix capacities like that and wire them in parallel... With a slow enough discharge it might not matter, but I think you'll run the smaller pack dry too fast and damage it if you try to discharge past twice the smaller packs capacity.
Edit: Nevermind, this isn't a problem. Just need to make sure both packs are at the same voltage before connecting them.

Interested to see how the deadcat mod flies! Have you checked the blackbox logs with your arm extensions to see if there are any low frequency vibrations?

Hi V-22,

Yeah, I knew that connecting the batteries would work. 

I will try to get a flight in during the next few days.

As for Blackbox. The BetaFPV FC that I just put in the Phantom-X doesn't have flash memory {so no blackbox data}. In fact, most of my FCs don't have flash memory for Blackbox, so there are no logs. All that I have is what I see in the OSD and how it "feels" when flying. 

At this point, I have not yet tuned any of my quads. Mostly, they fly fine with the factory tune. Plus, the ones that I use for experimentation get changed to often to mess with tuning which I would only consider if the build was not going to change. So far, I pretty much run with the factory tune on everything {at some point, I might actually tune something}.