Aprilamille's (Mike's) VPModels' Cubic build

[apriliamille]

Well figured I would share my attempt at building this model. I got the Cubic this year from Aloft

I have never built something targeting at the precision of building like this. Others might say "pfft child's play" but its new to me as my prior build experience has been building 25 percent to 35 percent yaks, extras, edges etc etc. So here it goes. This is gonna be a slow build so i dont mess up and i still have to work

Initial measurements and thoughts i have on gear

total kilogram 0.994

plane 0.691
Fuse 0.078
RW 0.252
LW 0.246
Rudder 0.023
Boom 0.03
Parts bag 0.062

electrics 0.303

kst x6 0.06

motor 0.072 (tbd pending how much weight i need to cg the plane i will order motor of appropriate weight)
rx 0.01 TW R10 (this glider looks to have a pure carbon fuse so i want the 3 antennaes to go out of the fuse)
esc 0.028 talon 35
Spinner 32 0.013
props 0.006
3s 1000 ? 0.069
noobie misc 0.03 (glue, wire)
castle bec 2 6-8v 0.015 (why not. its some added weight but im intrigued of actually having servos that can handle some voltage beyond an esc bec

 

[apriliamille]

SO I started on the wings. I had quite a fit getting servo wires into the wings. They put what ever from Europe that equals a sullivan golden rod plastic tube on the leading edge side of the wing going down each wing to the servo bays. It took 5 ish hours for me to get the servo wires ran (that will teach me for not having CA kicker on hand) and i have no clue why i didnt use floss until i texted my friend griping about what a pain in the butt this was after 4 hours of failed attempts I ended up using an internal tube of one of my goldenrods sliding it inside the one built into the wing. It had the floss in it and i CA the floss knot i put on the servo wire and when it dried the old fashioned way i got the wires in place.

The servo trays that come with the model are pretty dang cool and i wish i had the print file for this so i could print a bunch of to keep on hand for other various builds down the road. i think they are that neat. I had to dremel some of the trays out as i think they were designed for x08h not the x08h + which i have on hand. but they seem kind of generic for kst 06 and 08.

The other thread someone talked about the Cubic I think Wayne mentioned to not mess with the internal foam core of these planes for the IDS type system so I had to take out a chunk of the rohacell foam for the x08h + to fit. i kind of filled the hole with epoxy and cavasil and then bored into it for the servo to fit. the one picture shows me forgetting that i need to have the servo arm horn at the leading edge not to the rear of the ring so you can see the epoxy cavasil already in there as i start on the proper hold position

I ran a straight edge once i had the fitting of the servo and tray into the servo bay and had a few "clicks or catches" so I ended up sanding the bottom of the trays to fit.

Right now the trays are ready for gluing but im gonna take a break. the measurements for the tray to the leading edge of the flap or aileron are as follows:


Right wing: aileron 28.7mm flap 35.8 mm
left wing : aileron 28.6 mm flap 35.9 mm

 

[Wayne]

Looking good!

Yes, servo wires can be a pain. I like to use a little thin music wire and a bit of tape. Usually does the trick, but each model offers a new complication of some sort.

 

[Doc J]

Looking good!

Yes, servo wires can be a pain. I like to use a little thin music wire and a bit of tape. Usually does the trick, but each model offers a new complication of some sort.

Same but I use "Bowden" Bike brake cable

Doc.

 

[apriliamille]

Not much to add photo wise. While I am not embarrassed of what I do not know I am still shy so not really any pics of my mess ups.

I was rather proud of how exact, precise and weight economical I was on routing wire to the servo bays. Until I had the dreadfull experience of not actually having a splicing tool for such stinking tiny servo wires. I had lost so much length of wire from the servos getting them properly stripped to solder to the servo wires that I literally had zero room at the root for the mpx connectors to be soldered. (i could not get my super hero sized soldering station solder iron inside the root to actually solder to the connector and not risk the foam core) sooo....re routing of servo wires happened again with more new wire. my first batch of mpx soldered had bled solder between the posts the servo wires. so off they came. my second set of mpx i got them all set up, servo tested and put horns on the servos (still not glued in yet) so i rested them vertically against a wall, only to whack the mpx connectors clean off from not using enough solder. I had not glued the mpx in as i wanted my friend who has done way way way mooooooreee glider builds than me examine them as i figured once glued into that foam root it would be the end game thus the non supported pressure snapped the connector clean off from the soldered wire. so with great profanities i wimped out.. I am just fine with servo wire males to females going into the fuse, enough of this pain and insanity. so left to do is line up the servo horns, and figure out the surface control horns, glue them in along with the mounting the servos and work on linkages.

my friend and i are planning on getting together in another week or two to examine where I am at with the wings and my oh my what the heck are we gonna do with a carbon boom that has no indexes on where the tail feathers are to go along with how we are going to stabilize the european golden rods inside a boom we cant reach so there is no flex when the golden rod pushes against the tail control surfaces. please note i do not know what to call these things. they look like sullivan golden rods but they dont look like that as well and they are from europe so im calling them european golden rods. they are a plastic tube with an actual metal wire inside of the tube unlike golden rods which have a yellow plastic thingy going inside the tube..

my picture sure shows my love of masking tape and notes

 

[Wayne]

Yeah, wiring up a wing is always something I like to avoid, but like most things after some practice it gets easier.

Soldering Tips:
Get one of the newer ceramic element soldering irons, you can find them on Amazon and similar for pretty dirt cheap. They are about 1000% better than the old junk we used to use. They heat up really fast and just perform really well.

Keep the tip clean with a wet sponge or a tip cleaner. When in doubt, clean the tip! A clean tip makes your life so much better!

Do not set the iron to a super high heat, it just messes up the tip faster when set really high. You wants hot enough to melt the solder nice and fast, and heat up the items you are soldering.

For the small stuff, use a fine tip on the iron, for bigger stuff a bigger tip is a must.

Tin the tip, and the wires and pins with a bit of solder. "Tinning" will result in nice clean silver finish. If it is not shiny, it is not right. BLACK = way to hot. crusty silver = too cold. Neither is any good. Practice and adjust until you get perfect shiny silver, set up correctly it should be very easy.

With both parts tinned, then come back and put the parts together, and you should be able to very quickly heat them up with the iron and melt the existing solder and allow it to flow to both parts. Make sure it flows to both parts, then remove the iron, but hold the parts still until things cool a bit. The result should be a VERY CLEAN shiny joint that is strong if you pull on it.

A bit of solder on the soldering iron when joining the pre-tinned items will make it easier to heat the parts and join them faster and cleaner.

Working out the correct amount of solder will take some time. The goal is as little as you can get away with, but with good coverage of the entire joint. Many new folks make the mistake of either way too little or way too much solder. Too much and it will drip where you don't want it to drip, but more importantly, it will also work its way up thw wire under the insulation, and this makes the wire brittle and prone to breaking later in life.

Another common error is making rather massive solder joints. For example, when soldering servo wire, the joint can be as small as 1/8" (3mm), and this will probably be much stronger and function better than a joint that is a lot longer.

Don't forget to slip on your heatshrink before joining. LOL (Notice I listed this last.. you will forget this about 10% of the time.. I do!)

I like to use a lighter or little torch to shrink the heatshrink, but you need to be fast and keep the heat off the wire itself. A heat gun can be used on bigger stuff, but I hate it for the little stuff.

The above may or may not help you, but it may well help someone else following along.

 

[apriliamille]

thx for the guidance on this

 

[Wayne]

I forgot to talk about the cables (bowdens)
Here is a quote from an email user that wanted to help:
Please help Mike with the Bowden tube by maybe suggesting that he run music wire down the Bowden tube, coat the Bowden tube with epoxy, run the Bowden tube down the boom and use neodymium magnets on the outside of the tube to pull the music wire against the inside of the tube. I like to use epoxy, as CA can expand and distort the Bowden tube causing high drag with close fitting push rods.

 

[apriliamille]

Thank you and thank them for them for the idea. this is helping my brain to start spinning as I noted Doc talk about something about a bike cable and will explore options on how i can create enough magnetic force to get this to work to get the stuff installed (probably wont need much magnetic force but how would i know, first time doing it )

 

[Wayne]

The music wire inside the bowden should do the trick, it is a steel wire and actually works really well. If you have an old outrunner motor, they are a great source for super strong little magnets.

 

[Doc J]

The music wire inside the bowden should do the trick, it is a steel wire and actually works really well. If you have an old outrunner motor, they are a great source for super strong little magnets.

Years ago, in the days of the old Multiplex models—like the Flamingo and Alpina—they used music wire cables. As Wayne said, they work well and are stiff enough to be "non-kink " unless forced when the carrier tubes are attached to the inside of the fuselage. Not being smart enough to use magnets, we taped the carrier tube with its wire to the inside of the fuselage and used a variety of awkward, long glue applicators to glue it. Messy if you are not very careful.

Bowden cables (Bike brakes, etc.) are much more flexible and, therefore, suitable for navigating gentle bends like the one on the new Ridge Runt Tailplane. But there are several grades and several weights, so you need a suitable one that is not too thick. Some are like ship's hawsers. A good high-end bike shop should be able to supply whatever you want but remember, there is no direct drive substitute.

1. Bowden cable = some backlash - this is inevitable.
2. Steel wire cables/pushrods - if done well, these will have little backlash.
3. Direct drive/IDS - can be zero backlash.

For lubrication, we used to be able to get some spray gunk called "instant Teflon"—or something like that. A puff of that stuff inside the carrier tube would make it slick as a racing snake for years. But don't; whatever you do, get it on the outside of the carrier tube, or you will never glue it to anything.

Hope that helps.

Doc.

 

[gp49]

...

The servo trays that come with the model are pretty dang cool and i wish i had the print file for this so i could print a bunch of to keep on hand for other various builds down the road. i think they are that neat. I had to dremel some of the trays out as i think they were designed for x08h not the x08h + which i have on hand. but they seem kind of generic for kst 06 and 08.

....

@apriliamille try this website on your computer, open the .stl file folder. Lots of options for servo trays!

wing-servo-frame/README.md at master · guillaumef/wing-servo-frame

Wing servo frame - fully parametric - arms/bearing - servo database - guillaumef/wing-servo-frame

github.com

 

[apriliamille]

well gosh im such a bull in china shop. with in an hour of reading about the magnet suggestion i did an amazon order for magnets and i got TONS of motors and it never crossed my mind

GP49 thx for the link

there is not going to be much done on the Cubic this weekend. im going to mask tape between the servo and control surface and start planning alignment of the control horns. My friend and I are still planning a meet up this upcoming week to look at the various surface horns we have on hand and compare to the ones that came with the kit. We are still discussing what actual material to use for the control linkages for the wings. Things we have discussed is doing mp jet couplers glued into carbon rods with clevises, a hollow carbon rod with a 2mm all thread then clevises (this came to mind as I did a few WildHare giant scales with this method but 4-40 from their assembly manuals) or a z bend to uhhhh what ever those thingies i cant remember the name of that you poke the wire into and then a set screw clamps down on it then a drop of CA (back in the day a few of my 3D Hobby Shop 50 ish inch veloxes and extras used)

We will look at and start a game plan on the boom work (i actually thought since this plane looks so DLG ish in the rear that I brought up doing the spring in the control surface with a pull only method but in the end we shot this idea down). My only thought on mounting the elevator and rudder surfaces involves a machine shop with a lathe and a dial caliper (which i dont have nor have any machinist friends) but my friend has a plan i think that wont involve what i was thinking

dont want to dive to much into my private life but life reasons had made me take 4 years off from flying. I have boxes in the closet that involves a Reichard Rapid (dont know if this is even available anymore so build it and fly it like i stole it) a CCM Toy and I might even build a very old never out of the box Hyperion 40E extra 260 or the 25% WIldHare edge (intentionally never built so far as its serial number 1 but WIldHare is closed now). so i will probably tinker with those until we meet up this upcoming week. I am a power pilot converted to gliders when I moved from Nevada to Utah (near Soar Utah's Point of the Mountain) 10 or so years ago so i got various power field models built and in boxes

I dont know if i will do a build log on those planes as I do not know the eitiquette or if there is etiquette for posting build logs of planes not purchased from Aloft. Besides, Ali has a very detailed youtube assembly of the CCM Toy.

 

[apriliamille]

Im gonna share these pictures that I put in another thread so they are here if someone looks to this thread in the future for ideas on building. They are from VP via email to me

 

[Wayne]

Sure, you are welcome to share other builds and links to other products etc. We don't play those games here. If someone comes on just to share links to a given business, they are vaporized, but that is about it.

The MP Jet and tube solution makes for a clean and robust setup. Not a bad plan at all. The forces involved are going to be very low, this should be well beyond what is needed.

The tail - I have not built on of these yet, but think you can build the tail onto the boom before attaching the boom to the fuselage?? If so, just need to square up the 2 tails to one another, and let them cure before attaching the boom to the fuselage, again squaring it up to the wing.

Here is a sister ship to the Cubic, you can see how this one was built out:

 

[apriliamille]

my goodness, that is one sexy looking plane in the video

 

[apriliamille]

my goodness, that is one sexy looking plane in the video

 

[Doc J]

my goodness, that is one sexy looking plane in the video

Sansibear - my old friend Henning Schmidt.

He's a good guy.

Doc.

 

[Wayne]

Yep, same planes, but he often times changes the names. He calls the Cubic a Dajango 3.4M or something like that.

 

[apriliamille]

well its a good thing for my wallet and or credit card you aint got one of those 2.5 in the carbon hand chucking format.. im in love with that thing (literally why shell out a grand on a 1.5 dlg when that thing looks just fine at hand tossing) as i watched the other video of that guy tossing it on the beautiful grassy mild slope. I also am intrigued by that 2.5 unbox video and those finger grip thingies. i kind of would like a pair or two of those to put on the cubic to help toss it with authority and another set in the parts boxes for rainy build days or what not.

I honestly dont know why it took soo long for "thermal gliding" to peek my interest. I mean i was running power planes back in 2008 and now for some odd reason this year in 2024 i am in a "all about learning about lift" phase of the hobby. maybe its cuz ive done the giant gassers / electric acro, and pre flybarless helis and random sloping and then offroad rc and on road rc and now thermalling is all that is left. now im not saying i am a master of all aspects its just some bug has me really wanting to do the thermal thing

i have no build update on the Cubic. i got flustered on my mess up while working on the Reichard Rapid wing servos and aileron horns over the weekend. either i was drunk , doped up or maybe my glasses were on crooked cuz its all kind of crooked with the horns and linkages. I also dont do hobby stuff on Mon or Tues as they are my longest and most tiring days of work