Balsa USA 1/4 Scale Cub – Part 6: Wing Mounting and Struts

It seems like the work on the Balsa USA Cub never ends.  Some of it is just that the BUSA kit seems to be more complicated than most and the way the designer/manufacturer chose to do things sometimes makes no sense to me.  Also, since I got this as a partially constructed kit, I’m having to go back over everything to see what parts the previous builder changed, skipped or just didn’t follow directions well!?  Of course the fact that I’m “converting” it to a super cub is not helping the process along either!

One of the things I have spent significant time on concerns the wing attachment methods.  The original plans call for a couple pegs through the wing roots and two bolts as well to hold each panel in place.  In addition the struts are load bearing.  They are bolted to the ply plate that makes up the fuselage floor and screwed into hard points on the wing.  When I first tried to assemble them I quickly found the whole process to be frustrating and overly difficult.  Getting the wings in place and holding them there while installing the bolts was difficult and that was without any windows in place!  I can’t imagine what a PITA this would be once the plane was all covered and the windows all in.  I quickly realized something had to change.  In addition, it seemed entirely possible to cause some damage to the plane while installing the wing struts as the entire weight of the wings at that point is hanging on the wing roots and the structure between doesn’t seem all that strong.  Thus the need for load bearing struts!

So I first added a wing tube to each wing and fashioned some bracing inside the top of the cockpit area to give it some strength.  Now there is something a bit more substantial to hold the wings while the struts are being installed at the flying site.   You can see the aluminum tube in the wing center joint and inside the wing panels below.  There is a carbon fiber tube inside.

The strut attachment method seems a bit ridiculous as well with no concession to ease of installation or transport.  The vertical wires that connect to the wing mid-point don’t seem to be movable or easily removable so transporting the struts looked to be a pretty interesting prospect.  Add to that the directions for attaching the struts to the wing hard points uses wood screws… which to me is just a uniquely bad idea.  How many times reassembling this bird before a screw is over tightened, stripping the wood and weakening this critical attachment point??  I understand these kits are designed to be very scale like and that most builders are going to modify all of this to make it even more so.  Maybe they don’t intend to fly the plane all that often… but for me, if it isn’t reasonably simple to assemble when I get to the field it will likely get little flight time and become a hangar queen.   I’ll take slightly less scale like and more functional and easy to get in the air over scale in this case.  BUSA might as well just say “figure out a method that will handle the stresses and that you find acceptable to assemble” , and leave it at that.  The directions they do provide seem to me to be a poor attempt at best.

After a lot of fits and starts and coming up with several plans and then rejecting them I came across some struts and connecting hardware from a 1/4 scale clipped wing cub at a swap meet.   The struts were far to short but I cut off the ends in hopes of using the attachments.

I don’t know why he had them but the gentleman had 2 or three sets so I picked up a set for myself.  I looked at them twice with great regret that they were for a clipped wing cub but then figured if nothing else I could use much of the hardware.  Once I looked closely at the hardware the wheels started spinning and I realized the hardware alone was more than worth the price.  So I created some Frankenstein struts.

Below is a snapshot of the mid-wing attachment point.  Using the threaded “eyelets” with threads tapped into the hardwood blocks in combination with the hollow aluminum tubes with built in attachment points, a 4-40 bolt and nylon insert nut makes for a secure attachment point.  The tubes and wires were trimmed and epoxied together after adding some grooves to the wire to insure the glue gets a good grip.

On the other end of the wire, I used some nylon landing gear wire straps and #2 screws to create an attachment point that is both strong and allows for an easy pivot point for storage.  This shows them pivoted down against the struts for storage.

 

At the outer attachment point, the main strut connections are bolted to the hard point with 4-40 bolts and blind nuts.  The ends of the wood struts were trimmed to fit inside the aluminum tube ends as well and attached with glue and screws to the wood strut ends.  This took extensive trimming and measuring to get the correct length and support the wings in the correct position.  Each is somewhat custom!  The nice thing is the ends of the struts that I recycled have a threaded rod at each end for fine adjustment.

 

I attached the outer aluminum ends with expanding gorilla glue and some #2 screws to “pin” them in place.  Now I have a nice pivoting attachment point that I don’t intend to disassemble often as the struts can be pivoted down to sit flat on the wing for storage.

Each strut, once adjusted on final assembly, should take only 1 bolt at the attachment point on the bottom of the body and 2 more at the mid-strut attach point in order to easily assemble or disassemble the aircraft and still provide plenty of needed support.

Combined with the wing tubes, which require a single bolt on each side to attach, the entire assembly process shouldn’t take more than about 5-10 minutes and I expect it to be both strong and fairly straight forward to accomplish.

There is still a long list of projects to get this plane ready to fly, some small like hinging of the wing surfaces, and some large like getting the cabin windows, windshield and door assemblies all finished.  More updates soon.

P-47 Bonnie reassembly and lessons learned.

My local hobby shop, Hobby RC, got my replacement body and decal set in quickly and so the process of making this craft flight worthy again could begin!

Immediately upon unpacking a couple of things became obvious.  As you can see here:

The decal set I ordered would not be necessary.  Unfortunately the picture on the web site showed the spare part without the graphics.  I’m happy this is the case but could have saved $15 if I’d known.

Next I noticed the rudder was not attached and I had no idea to this point how it was attached… the original came on my plane… I’m pretty sure…

Turns out the rudder just clips onto the body by the use of built in plastic clips and pins built into the two parts.  You simply push it on and it pops in place…  Couldn’t be much simpler.

After screwing on the two halves the elevator with the 4 black screws.

I pushed the rudder on and started flexing it back and forth when I noticed that it didn’t allow for much throw (I had been thinking it needed a bit more) plus I noticed that it tended to flex the elevator joiner, resulting in some deflection…  that had to change.  So taking advantage of that easy removal, I popped it back off and opened up the pass through slot with a sanding drum on my electric rotary tool.  You can see how tight it is here in the before photo:

Quite a bit of material needs to be removed to get a significant amount of throw AND keep the pressure off the elevator joiner.  Here’s the old and new with the modification.

And here is what it looks like installed.

 This allows for the maximum throw allowed by the factory servo and linkage setup without binding.  Sliding the push rods back in place and installing the servos on the rails was pretty straight forward.  I notice the servos have no rubber grommets on the tabs… though I suppose in a foam body electric, vibration problems are fairly limited so no need.

While I was working on the tail, I flipped the plane over and went to work reinstalling the retractable tail gear.  Only something was missing!

The plastic insert that everything mounts into was not in the new body… time for some surgery on the old body again…  You can see here that it takes a lot of carving to get this thing out.

And here is the piece that comes out.  It takes a little cleanup from here.  You need to get all the foam off of it to easily insert it into the new body.

After getting the plastic insert into the new body, mounting the servo followed by the retract itself was pretty straight forward.

Mounting the servo and retract outside the aircraft is more straight forward than it was taking it out while still inside the tail of the plane.  Route the wires (easier if you have “grabber” like the one you see here) and with a little glue on the contact points with the foam just slide the assembly back in place and we are back in business.  

Reattach the doors and springs (a little bending/adjustment is likely needed) and everything goes back together fairly easily.

Next I reinstalled servos and the control board with it’s associated plywood tray inside the fuselage as well as the connector boards in the wing root.  You’ll want to check your notes or photos on which wires plug into what as the labeling is helpful but not completely obvious.  Once again I ran into a small issue where my notes and pictures were insufficient.

Here is the starboard wing root 

Note the one socket is closest to the trailing edge of the wing.  As you reinstall the matching plate in the body, be conscious of this and note that the port side is opposite…  I just “assumed” that both would be installed similarly and it turns out not to be so.

Most everything else went back in with no issues, though I encourage you to take copious notes and photos if you have to do this for yourself.  It will help immensely to guide you in the rebuild, knowing which screws to use, etc…

As I was assembling for final adjustment of the servo linkages and testing I found one more casualty.  Here are two of the wing screws…

As you can see there was a bit of force exerted when one of the wing tips found the ground.  These bolts are a little bit soft (which worked in my favor in this case!) so I was able to simply use some padding around the bolt in order not to mar the threads and bend it back into shape with pliers.

I made a final “rebuild” step by peeling the custom graphic for my crew chief (my Grandfather) and successfully reapplied it to the the new fuselage.  Welcome home Grandpa! 

While the P-47 was in the shop, a few additions were also made.  With the addition of a telemetry module and associated sensors (GPS, G Force and Voltage sense wire…) I’ll be able to keep a better eye on my battery pack voltage, ground speed and other interesting tidbits.

This last weekend we had a nice event at the club field during which I got in 6 or 7 flights.  After a bit of elevator trim during the first flight, the Bonnie proved she was back in peak form.  Her pilot took another flight or two to get back in the groove…  I did make sure that the battery was securely attached to the battery tray before each flight and I may add additional measures to be sure the whole assemble does not leave the plane prematurely.  For now just being sure the straps on the tray also engage the hook and loop material on the battery seems to be working.

P-47 Bonnie gets some flights

Last weekend I managed to get out and put some flights on the 1500mm FMS P-47 Bonnie…  The short version is “very nice”!  Here “we” are after a couple of flights.

I’ve always had a soft spot in my heart for the mighty Jug for a couple of reasons.  The P-47 is a workman like craft.  She’s big and heavy, not the sexiest but she is powerful, deadly and protects her pilot.  P-47s were built in two places and one of them was the plant in Evansville, IN where my grandfather (mother’s side of the family) helped to build them!  There are family photos from the plant (which later became a Whirlpool plant that created lots of consumer appliances) showing gun testing going on in the middle of the night using tracers!   This was a 24×7 operation so darkness could not halt the process.  I can’t imagine living nearby and listening to those 8 .50 caliber machine guns going off at 2AM!  Just another hardship of war I suppose.  Most of those families probably had folks working in the plant and so understood well what was at stake.   In honor of grandpa, I added one customer graphic, making him the crew chief on my P-47.  His name was Jesse A. Lane.

With Grandpa taking care of the mechanicals, I got in a total of 5 flights that day and the plane performed well.  She has a wide flight envelope from nice and slow to fairly impressive high speed passes.  She kept up with an EDF that happened to be in the air during one of the flights and at the same time slowed down nicely with medium flap settings.  Gentle/slow landings combined with the ability to fly the plane fast enough to be convincing (a fighter should not spend a lot of time just floating along should it?).  This is a somewhat rare and welcome for a war bird and gives me hope that I will fly this more than “once in a while” as it makes the plane actually enjoyable to fly versus flying like a kite or white knuckle landings being the norm.

I still have some tuning to do… need to adjust the elevator to flap mixing and adjust my throws and expo settings to my liking.  Also need to double check that motor box “flexibility” that I noted in my first post on this airplane.  I may have imagined it, or it may just be a result of the down thrust built into the airplane, but it seemed as if the plane would push downward with application of full throttle.  Not a drastic issue and perhaps if I can firm up that motor box this would go away??  We shall see.

Overall, I am very happy with the flight characteristics and overall performance of this airplane.  It is the first war bird I’ve bought that I am looking forward to flying frequently in the near future.

From a non-flying perspective I did my usual cut outs from a styrofoam cooler and created a cradle and I purchased some wing bags to protect the soft foam, guns, etc…  That works well as long as you actually tie the cradle down in the trailer! 

The soft foam continues to be a concern so continued care is necessary but so far I’ve managed to keep bumps and bruises to a minimum.  Also, the wing connectors are holding up so far but I only have a dozen connects and disconnects on them so far so will have to watch those as well.  It’s also worth mentioning that the retracts have performed flawlessly up to now.  I attribute part of that to the fact that she lands pretty easily so they aren’t getting the abuse that a heavier bird would put on them.

Overall I am very happy with this aircraft.  FMS seems to have done a great job and I recommend you get one for yourself if you are so inclined.

FMS P-47 1500mm “Bonnie” added to the hangar

FMS 1500mm P-47 Razorback Bonnie PNP

After months of serious consideration, comparison and reading hundreds of comparison posts I finally pulled the trigger and picked up the 1500mm P47 from FMS.  As usual, my local hobby shop got me a great deal and in a few short days I had a rather large box full of airplane in my shop.

Bad : 

  • The foam is soft… dings and dents are already building up.
  • Some sloppy glue… the wing tip lenses are both a bit “slimed” with glue.  
  • Inner gear door linkage maladjusted… both were drooping  a bit, 2 turns on each clevis solved the issue
  • Wobbly motor mount.  Entire structure appears to be moving in the foam.
  • Finish is not as smooth as other foamy aircraft
  • Decals are thin, some lifted a bit, piece missing out of one
  • Bomb attachment.   Brackets pull out before release occurs

Good:

  • Overall finish is very pleasing with the exceptions noted above.  Lots of scale details, especially in the cockpit.  Ordinance, lights, 4 blade prop, panel lines etc…
  • Light weight and light wing loading along with flaps should make the airplane a kitten to land
  • Build is nearly complete out of the box.  Rare for a complex war bird like this.
  • Wing connection plate makes wing assembly simple… no chance of missed connections.

Questions

  • Wing connection plate… to loosen or not??
  • Carry method…  Wheels in the wings so what to do?

Let me expand a bit on the above in reverse order… First the questions.

There is a nifty connection plate and mating plug where the wing root meets the body.  Since the wing inserts into pockets and has two aligning rods, the connectors meet up perfectly and seat together snugly… or at least it appears so and they work nicely right now.  There are a few reports of issues with this connection.  Folks have had a few intermittent connections and the like.  Some people have avoided or resolved this issue by loosening the mounting screws on the plate mounting in the body.  I think the idea is that if the mount is not rigid, vibration and the like won’t cause an issue.  Should I pre-loosen these or wait for an issue (and hope I don’t crash when/if it happens)?

Carrying this plane is going to require some thought.  I can’t leave it assembled… there simply isn’t enough room in the trailer… but like a number of other planes the main gear is in the wings so once you take those off that round body there will have to be some sort of carrier created to keep the plane from becoming a hangar casualty!

Now for the good stuff…

The color scheme chosen for the bird has enough color and lots of striping so that it should be very visible in the sky and orientation shouldn’t be to hard to track.  The cockpit has some nice touches and the wingtip lights are nice and bright.  While not every panel line is captured, a vast majority are there and while they may be a bit more pronounced than needed it adds to overall look of the airplane.  From a few steps away, the plane shows nicely.

The weight of the aircraft is on the lighter end versus what i would expect from a warbird of this size so I’m expecting some good flying and landing characteristics, especially with flaps being available.  I doubt she will float, but I don’t expect to have to make super shallow landings at high speed that require huge amounts of runway either.  With the flaps deployed I would think a more ordinary approach will be possible, holding just a little extra throttle in to keep the wing flying.

The completeness of the build out of the box is impressive.  Attach elevator linkages once it is in place and assemble and mount the prop and you are about done!  Even the decals are applied in advance.  There isn’t much of the “Almost” in the “Almost Ready to Fly” P47!

The electronics in the P47 are by necessity a bit complicated but as opposed to other similar aircraft I’ve dealt with, FMS has done a great job of eliminating that issue.  Everything is pre-wired and connected and attaching the wings requires no messing with wires at all as the wings have a built in connector at the wing root that takes care of all that for you.

And then the bad…

This airplane is built out of some of the softest foam I’ve seen.  I’ve already accumulated a number of dings and dents… some wrinkles and thumbprints in the stab just from trying to get enough force on it to assemble it.   As well, the body has several dents just from resting it on my airplane stand which is made of harder foam.  This may actually bode well for it’s survival but I’m half expecting it to get “ugly” quick.  I’ve seen somewhere a suggestion that using a warm, wet rag may help relieve some of these but I’m worried about what that will do to the paint as well…

Speaking of the paint, it seems to have the same issue that I have seen on planes like the Carbon Z Cub.  It doesn’t take much to peel or flake it off.  Also there is some over-spray in some areas that occurred when the paint was applied.  I could wish for a bit better application. 

I have been adding some additional graphics and replacing some of the decals with vinyl and there is simply no way to get them off without peeling the paint underneath.  That might be to much to ask but in some spots it amazed me just how easy it came off.  I don’t want to do a full repaint so I’m only applying graphics that are the same or slightly larger than the original and doing everything I can to not lift the paint around any decal I remove… sometimes slicing it with a razor blade at the seams to maintain the surrounding paint.  Luckily the vinyl is a bit thicker and covers the patchy mix of paint and bare foam that is left behind.

I have found only two areas where the assembly/build of the plane could reasonably have been improved.  First is the wingtip light lenses.  There is a lot of sloppy glue work inside both lenses.  Unless I pull them off (which risks damaging the surrounding paint and foam) there isn’t much to do about the strings and globs of glue on the inside of the lenses.   Second is the engine mount.  It is obvious that the entire engine mount if flexing slightly as the motor runs up.  I’m not sure if it’s just a function of the soft foam or if some extra glue would solidify this…  I may eventually try injecting a small amount of expanding glue like Gorilla glue in a couple spots around the mount to see if it helps.  I don’t think the motor is going anywhere and balancing the prop might help minimize this issue as well but it’s something worth looking into.

Another minor issue was on the bombs.  The attachment method of the “brackets” into the top of the bombs was apparently a couple pins and spit (errr… I mean glue of course).  The second time I tried to detach them from the pylons on the plane, the bombs parted ways with the brackets.  A good application of Foam Tac and this problem seems to be resolved.  I also recommend you always attach and detach the bombs by grasping the plastic brackets versus the foam of the bombs themselves.  

I promise to follow up with some more info after a flight or two.

Spektrum iX12 – 1 month in…

Image result for spektrum ix12

One of my more recent additions to the RC hangar is not a new airplane but instead a new controller.  I have been using a DX18 for a few years and have found it to be an excellent radio.  I have zero complaints operationally with the 18 but I really like the newer designs that have come out without all the excess “chromed” plastic.  What’s the point in putting a coating over plastic that will eventually wrinkle/peal and otherwise just create issues?  It looks nice if you like chrome I suppose… never a big draw for me… and sometimes can create glare issues on especially sunny days.  Also, while not a big fan, there are times when a voice notification would be welcome.   I’ve held off because previously they were rigidly defined.  Want the radio to say “charge my battery!”?  Sorry, the only message available is “low battery”.

Spektrum’s approach of putting an Android tablet functionality “up front” in the iX12 sounded like it would have some nice advantages and I haven’t yet needed channel 13 and up on my DX18… so after a bit of research I took the plunge.  Hey, it’s a hobby!  If I’m going to get a little closer to the “bleeding” edge of technology in some facet of my life, this is the place to do it.  So after some time with the radio here is what I have observed and what I’ve done so far.

So far, I have had zero issues… I am somewhat familiar with Android so I think I have avoided some of the odd issues that folks on some of the forums have reported.  I moved 16 models over from my DX18 Gen 1 and everything has worked great so far.  I’ve flown a couple small quads plus 4 or 5 indoor airplanes and other than messing with the spoken prompts, I haven’t modified my setups at all.  Generally, I like the look and feel of the mechanicals of the transmitter.  If you’ve ever handled a DX9, you will find much of this radio to be very familiar.  Some parts of the box are even better, like the back sliders (which I rarely use) being much smoother.  The UI is not yet totally intuitive to me but I’m getting accustomed to it quickly.  I am beginning to like the text to speech options though I wish the audio defaulted to all OFF.  Will probably build myself a template for future use to accomplish this.

The radio is not capable of terribly loud audio levels and some have complained about that.  It certainly is not capable of the same volume of the DX9… Of course folks complained about distortion with the DX9 so Spektrum may not have been able to win this one!  Volume is not an issue for me as I intended from day one to use a blue tooth headset as I hate hearing the constant chatter of audio from other folks radios while I’m trying to fly.  I like to hear my aircraft (and others) and all that chatter is distracting and irritates me after a while.  I also think it impedes communication with my fellow pilots as needed for safety so I love the blue tooth headset option afforded by the Android interface. 

In order to make the audio usable, not annoy my fellow pilots and maintain safety I intend to use a single earpiece.  I bought the Sentry BT950 so I can use whichever ear I like… So far I like how it sits on my neck and audio seems plenty loud.  I have a couple other Bluetooth sets so I can try some others if need be but this one is a nice cheap option I can afford to leave in my flight case.

I also picked up an inexpensive blue tooth keyboard and mouse (Logitech model K380 and model M535, refurbished).  Both paired up and worked right off.  One oddity that was noted in some of the forums was apparent immediately.  When used in conjunction with the iX12, the enter key doesn’t function as you would expect.  So far the esc key seems to function in place of the enter key for text entry.  I’d bet there is an app that would remap the keys for me but I’m OK with using the esc key for this purpose.  The mouse works great and even has a “gesture” button that can be used to do swipes and such so you can pull up the various “side” menus etc… I’ve only used the mouse and keyboard a bit during setup of new aircraft but so far it seems like a great alternative to using the screen based keyboard to create all the text to speech prompts, timer call outs etc…  Do I need them to accomplish this?  No, but I like to have the option for anything that is going to require much typing.  I don’t even like to send long texts on my touch screen Android phone so having a keyboard is a nice option for me.   All my blue tooth hardware total cost me $70 and I will use some of it for other things so in my mind they are cheap at the price and nice to have options.

I routinely pull pictures directly from the web using the Chrome browser on the radio to use as my icons in the model selection screens and downloading the updates from google play is a nice and familiar way to operate so the ability to connect to a WiFi network directly from the radio is another nice to have option.  All in all, I like the radio so far.  There have been complaints about some issues (minor for me) like the audio level, slower model selection than other radios (30 seconds to change models versus maybe 5-10 on most radios) and the fact that it takes about 2.5 minutes to go from powered down to fully functional the first time you power up at the field.  This last is something you adapt to fairly quickly.  Just turn it on when you get to the flying site.  By the time you get a plane or two out, all is ready to go.  During the day, simply double tap the power button and go into sleep mode after each flight.  Coming back to full power up from there is a couple seconds.  The battery will last all day using this routine. 

As I worked with the radio a bit there were a couple of additions I decided were worthwhile.  First, there is a company (Powerhobby) who sells vinyl wraps for the face of many transmitters including the iX12.  I have occasionally dropped something onto the face of my transmitters in the past and I thought maybe this might give it a bit of extra protection.   Also a little individuality never hurts… I already know of one other guy in the club who has an iX12 on order so now there won’t be any mistaking mine for his!  Installation of the vinyl was a bit tedious but not terribly so and I think the result is pretty nice.  Here is what mine looks like after the application.

In addition I quickly noticed that the touch screen was going to often get greasy and spattered, etc… so I decided to take the leap and try to find a good screen protector.  I have not had great luck with the cheap plastic sheets you get for cell phones… they either mute the sensitivity of the screen, cause visibility issues, etc…  so I looked for a glass cover for this use and actually found one sold through Radiocontronics.  It is made of something marketed as “AirGlass” and is apparently from a company called Brotect.  I hesitated to spend ~$24 with shipping for what looks like a highly hyped piece of plastic cut to shape… but I have been pleasantly surprised.

Installation was pretty straight forward.  Clean with supplied lens cloth and carefully drop into place.  Done.  So far I have to say the screen is every bit as responsive as ever, there are zero bubbles or imperfections and so far it seems to pick up less dirt and finger “grease” than the screen itself did.  I wish it were just a millimeter or so bigger in both dimensions than it is… there is a very fine line around the screen that is visible if you know what to look for but is probably not noticeable to anyone else.  That aside though, I have to say it is working as advertised and if it keeps all those microfine scratches off my screen that my DX18 seemed to accumulate regularly (and it wasn’t even touchscreen) than I will be ecstatic.

At around the $600 mark, I think there is a lot to like in this radio.  And yes, I am a bit of a Spektrum fan for which I make no apologies.  I have worked with several other brands like Futaba, Hitec, Airtronics, Multiplex , Graupner and a couple others I can’t even recall.  All of them have some interesting features and strengths but it is hard to beat the Spektrum value for the dollar, excellent support and good balance of feature set with ease of programming.  The iX12 leans toward the more complex end of their line of radios so it may not be the ultimate answer for those who are not smartphone savvy or that are just happy with their DX7s or 9 or whatever but I think I’m going to enjoy it for quite some time.  At least until the iX12 Gen 2… or iX18 or whatever hits the market next! 

 

X1 Pro DC plus ePowerBox 17A Power Supply

I’m constantly updating and hopefully upgrading my RC gear and recently I decided I needed a new charger. The one I bought is the Hitec X1 Pro.  I bought it in combination with the Powerbox 17A power supply. 

Hitec RCD 61070 X1 Pro DC Multi-Charger E Powerbox 17 Combo

A couple of reasons I think the X1 Pro will serve my purposes.

1. Power
2. Portability

I have been doing some flying indoors as well as running an RC car at the local track and I found that my current charging options (a Hitec X4 CD charger and my PL6) just don’t fit the bill for a couple reasons. The Hitec is adequate for some needs but with only 50W power per channel it can be a bit slow for some needs and requires a DC power supply to run it which adds more weight and bulk… especially since all my 12V supplies are fairly heavy and large. The PL6 certainly has the power but it also needs a DC supply and it is a fairly pricey charger so I don’t like to drag it around very much for fear of damaging it. It usually stays in the airplane trailer or the shop.

After my buddy Corey picked up the combo X1 and power supply I had a brief look at it and decided it might be the solution. Power supply and all it is very small and is capable of charging at 180W! That means I can charge a 2S (for the car) at around 20A if I like! This could be a very quick charge for a single battery or I could charge several of my more common aircraft batteries at once with a parallel board.  Even with the power supply the unit is a <6″ cube so portability is excellent as well. Another bonus is it can discharge at 30W which is better than most chargers so getting down to storage charge when needed is quicker as well. Second bonus is the price for the package.  I have seen them from $130 to as low as $80 for the pair… Hard to beat even at the higher end of the price range.  So I brought one home today.

When you unbox the X1 and the power box you will find that you can connect the two with some nifty little double ended banana plugs.  They supplied 4… 2 are needed.  I suppose they will eventually wear out so having spares is a plus.  I removed the little rubber boot on the bottom of the X1 and plugged the two units together with the double ended bananas and presto, I had a fairly compact and powerful AC powered charger. 

In fact, it is compact enough that I don’t think I’ll be taking it apart anytime soon so I decided to come up with a way to keep them semi permanently attached in this configuration.  I can see where leaving it this way and packing and unpacking it might stress the bananas so here’s what I came up with.

First I loosened some of the cap heads on each side where they are closely adjacent on the two units.  Then I took some wire and bent it around in S curves such that tightening the screws would capture the wire.  Here’s a closeup.

I did this near all 4 corners and now the unit is practically one piece.  Since I used fairly small, semi-soft wire I can easily take this back apart if I decide I want to modify this setup later.  I may eventually make something more like a “latch” from servo arms or something but for now I think this will work well.

My only trepidation at this point is I need to find a proper box or padded bag to put the unit in to protect it when it’s in my car “satchel” where it might get rubbed against and scratched.

I have only run the charger a couple times so far but I am quickly getting accustomed to the controls (just a slight difference from most I have used). 

Finally, the first time I tried to pull the connection that goes to the balance board from the charger, I had real trouble releasing the catch.  There didn’t seem to be enough room between the connector and the case to release it and pull it out.  I almost pulled the connector right off the pins!  A razor knife took care of the pesky latch!   Nothing else I have needs a latch on this connection so I don’t think I’ll need it.

So far, I think the little X1 with the Powerbox 17A is going to be a welcome addition to the charging lineup around here.  I have seen some indications that they may soon do away with this charger and power supply!  I hope not as it seems to fill a niche for me and think others may be interested as well. 

 

 

Dumas Windy… now “This sucker’s electrical!”

After swapping in the power system from an E-Flite Timber, the Windy seemed to be ready to go but then I started to notice what sounded like a stutter on startup and sometimes even at higher power settings.  I did some research and found a lot of speculation around causes. 

Some report that connection issues cause the problem.  It seems a poor connection on one of the 3 wires coming from the speed controller can be to blame.  Others claimed it was a setting in the speed controller (timing) that creates the issue.  As best I could determine the connections on the motor end seemed fine so I tried re-soldering the bullets on the speed controller, then replaced the wires entirely but neither made a difference.  Since the motor is fairly inexpensive, I decided to try that next and placed an order.

While awaiting the new motor, I did some research and tried to program the timing on the 40A ESC that comes in the Timber.  I didn’t consider this to be a very likely scenario as most Timber’s don’t seem to make this sound but I thought I’d give it a try.  Based on my experience… don’t bother!  I have programmed several brands and types in the past and I tried to follow the published directions to no avail.  After researching on-line, I have found that this is the experience of all but a lucky few with this ESC.  Remind me to bypass the E-Flite line of speed controllers in the future.

Unfortunately, in my experience, E-Flite tends to have an appalling lack of information on the products installed in many of their ARFs.  This makes it very difficult to pick an upgrade part or replace a failed component, especially in the case of a part that is difficult or impossible to acquire from the manufacturer.  I am quite fond of the “Power” line of motors however, but I usually stick to that product set and avoid the motors that come only as part of an ARF.  I only tried this one as it was so inexpensive.

In any case, after the new motor arrived I tested and found it made ZERO difference!  Back to the drawing board.  The next step was to get a new speed controller.  My “go to” on speed controllers has always been Castle Creations.  In my experience, not only has the quality of the Castle products been high, but they offer many features that your average ESC doesn’t come with.  With the Castle ESC, I can get real time or recorded telemetry, programming either through my radio or via a cable to my laptop plus features like a throttle cut switch.  Yes, they are one of the more expensive manufacturers but I think they are generally worth the extra dollars.  Of course I am always looking for a discount!

A few days later I found a good deal on a 50A Phoenix Edge.  With a little extra overhead in the current handling capability plus the ability to handle up to 8S, programmable setting concerning timing, braking, etc… along with telemetry capabilities, etc… (I like to be able to move my gear on to other projects down the road) I cashed in a gift card to help soften the blow and made the purchase.  

After soldering on the appropriate bullets and power connectors, I tested with the Castle and the motor purred like a kitten… or screamed like a vacuum cleaner gone berserk once the  prop was affixed!  Since this controller is not water proof I decided to take some precautions.  First I hid it away in the pod to shield it from most water and second I did a quick water resistant treatment with my handy bottle of Corrosion X.  I have had good luck with components treated with Corrosion X being dunked (complete submergence)  and continuing to run so it has become my go to for insurance against water damage.

Here’s the dunk process to apply the Corrosion X. 

   

Then I let it drain for 10 minutes or so.

After a quick wipe with a paper towel to remove some excess from the wires I nestled it in the top of the pod with some foam around it to keep things snug

Then I buttoned it all up and tucked the wires well away from the propeller!

In testing with a 4 cell battery, the Windy was able to taxi around on my short carpet in the shop and readily pick up speed and turn.   I am looking forward to getting some test runs on the snow and later at the pond.  Best guess is that I may have a bit more power than before… I’ll try to at least add a comment here after some testing.  Wish me luck!

 

Tugster Tug Boat kit by ZippKits.com

During our sojourn to Toledo, Ohio for the annual weak signals show many of us picked up some new toys.  One of the items that found its way home with us was the ZippKits “Tugster” tug boat kit, purchased by my friend Steve.  He had the idea of building up the Tugster for use in aircraft retrieval.

Now, about 6 months later, the little tug boat has been assembled and prettied up for its big debut.  I think Steve put it all together in just the last couple weeks.  Here is the big launch.

From Steve’s description, the little tug went together quickly and fairly easily. And it appears to have good power!

Steve also reported that the Hardware Kit was quite complete and had pretty much everything needed minus the radio system (receiver and transmitter needed).

Here is a side by side with my Timber out on her floats for the first time.

The little boat seems to have quite a bit of power.  Certainly it easily shoved the Timber around!  The supplied batteries (2 x 6V 4.5AH batteries) needed only 450mah to recharge to full after out poking around at the pond for the better part of an hour the other night so it is hard to imagine recharge being needed during a day at the lake.

The Tugster may see some action here in a couple days as we have our club float fly this weekend.  We’ll see how she does as a real work boat.

Telemaster 40 becomes glider tug

I recently installed a glider tow release into my Telemaster 40.  Partly I did this because I could and partly it was because I have a couple of fellow RC club members who own gliders that I have towed up before and I sold the old tow plane (the Carbon Cub) so felt like I needed to have a replacement.  The Telemaster sports an Electrifly .80 motor along with a Talon 90 speed controller.  This combo, powered by a 6S battery (usually a 4000 but now frequently a 4500mah) has a lot of pull to spare.  The Telemaster only weighs about 5.5 lbs ready to fly so pulling a couple pounds of glider is fairly effortless.

I found a nice release to use and with a little surgery it was firmly ensconced in my airplane.  Here are a few pics of the install.  

Here’s the unit I purchased.  This one is made by TopModel and is very stout but not extremely heavy.

I want to install it just ahead of this bulkhead near the trailing edge of the wing

To do that requires access to the other side so cut open the bottom…

Mounting it requires getting  a good grip on the nuts on the far side so forceps to the rescue!

 

And the construction of a tray for the servo to run the thing.

In my case I mounted this tray across the body with the servo shaft pointed toward the rear of the plane to give a nice straight up shot through the release.

Once the release is mounted, install the servo “tray” and cut the rod to length.

With a little radio magic, assigning a channel to a switch, setting endpoints etc… and you are all set.

Aside from getting access to mount it, nothing really difficult about the process.  It was easier to mount it just forward of the bulkhead near the trailing edge of the wing than to build out a bunch of new structure so that’s what I did.  It did necessitate notching into the trailing wing edge right at the root, but on this aircraft that is simple enough.   I was a bit concerned about whether it would hold up but based on this video it looks like we are in business.

 

https://youtu.be/fWAyZZC7gTA

 

As you can see, no all glider tows go smoothly.  One of the two KA-8s I was towing had some pretty nasty habits when in tow.  We are investigating but we are pretty sure either the wing or tail incidence is off or even variable due to damaged mounting hardware at the back of the wing.  It does make for some “exciting” flights for all concerned!!

I’m looking forward to more glider towing.  Using an electric plane makes this even easier as the preparation between flights is simple and while you are hooking up etc… you are burning very little “fuel” so more tows between “fuel stops”.  All in all this has been a success so far and I’m hoping for better tows in the future as both I and the glider pilots get more experience.  The tow release is working like a charm so far and I would certainly recommend it to anyone who wants to get into this facet of the hobby.

Flying the E-Flite Timber

I have been putting the majority of my flights lately on my E-Flite Timber.  It’s a rare trip to the field where I don’t run 4 or 5 batteries through it and some days I may do 10… especially on days when I just want to relax and not spend a lot of time assembling or hauling out the larger/more complicated stuff.

The airplane is just fun if you enjoy STOL and just slow relaxed flight as well as being a fair platform for basic loops, rolls, and other basic aerobatic maneuvers.  Since I added the multi-connex (see this article for details on those) to make it a two plug operation to connect the wing, getting it up and running is quick and easy.

Here is a video compilation of Timber flights to give you an idea of the flight envelope.  This includes looking forward/backward and out over the starboard wing over the course of several flights.

I have read thousands of posts outlining all the things that are “wrong” with the Timber and warning of dire consequences if you don’t “fix” the aircraft immediately upon assembling it.  For the most part, in my experience (we have 5 of these at our club right now) if you simply follow directions and assemble the plane according to directions it will fly wonderfully!  Even the battery tray favored by some, I find to be unnecessary and possibly even inconvenient/limiting as the battery compartment isn’t overly large to start with and this just uses up more room!  Loved that same concept in my Carbon Cub but not for me on this one.

There are a very few things that I would recommend doing to make things easier or avoid issues…  

  1.  The only critical issue I’d be concerned with is to check the prop balance.  Most will never have an issue if they don’t do this but I’m sure there are some that the prop is so badly out of balance that the airplane will destroy itself due to vibration.  If you run the motor and hear a lot of vibration noises… balance the prop.
  2. Do something (lots of choices) to make taking the wings on and off a bit easier like the connectors I mentioned earlier.  Some folks keep the wires attached and build holders that allow for easy transport in that mode.  Some don’t mind the wires as is.
  3. I did a wax job on my plane using floor wax.  This is excellent for keeping the plane clean and protecting the finish.  Not a necessity but helps with longevity.  I have an article on this here.
  4. Take the screws for the float pull-pull connections and hide them somewhere as soon as you find them.  They have a habit of disappearing, especially if stored on the airplane when not being used!
  5. Finally, I did not even try using the floats with the standard rudder linkage.   I had a similar setup on a previous plane and found both the “fishing line” pull system and the spring return to be problematic at best.  I removed one rudder and rigged the other for pull-pull using standard pull-pull braided cable just as I did on the previous plane.  If you want to read about that modification on the other plane you can find it here.

That’s about it. 

I fly mine without the optional slats right now… though I may add them later and really wish they were removable (sigh).  Reports vary widely but on a good 2200mah 3S, I average about 6 minute flights with 30-40% left in the battery at landing.  You can burn up a battery in 4 minutes on lots of throttle or you can coax it closer to 8 minutes if you are gentle… I’m measuring time spent above 20% throttle so actual flight time is usually a couple minutes longer.

In closing, this is quickly becoming my go to flyer for quick and easy flight.  It has a fairly wide flight envelope, is easy to assemble and transport and with the lights and floats, very versatile.  It may take the place of my Parkzone T28 as my “gotta have one” foamy.  Get one soon!

I will do another article soon on the SAFE and AS3X modes of this airplane and its included receiver.  For now I wouldn’t let that get in the way if you are interested in this airplane.  It won’t hurt you and it may be just what you’ve been looking for.  If you want to put your own receiver in it or turn all that off, that is possible as well and the plane flies well without it too!