Wednesday, November 29, 2017

Buzzard Bombshell Electric Conversion and Mods

About a year and a half ago I picked up this wonderful high wing balsa old timer at a swap meet.  I did not know what it was but I'm a sucker for an inexpensive balsa old timer, especially a three channel high wing.  He wanted $25.  I offered $15.  He threw in a motor, esc, and two servos and we settled for the $25 he was asking!  I was a happy camper.

After some time and a bunch of Internet searching, I finally discovered that what I had bought was a plane called the Buzzard Bombshell.  The original design was done and built by Joe Konefes in 1940  with about a 72 inch wing span.  It was intended as a free flight as RC gear was way too expensive for most people.  This plane was designed to head up as high as so many ounces of fuel would take it and then glide for as long as possible (Joe flew his for over 49 minutes at the 1940 NATS).  To help with extended glide times they incorporated large tail surfaces that helped with lift and moved the CG to 50% or more back from the leading edge.  With the heavy motors of the time, this made for an interesting stubby nose look.

Mine was a more current and smaller version that was intended for 1/2A power sources.  It looks like it was setup for a Cox .049 judging from the mounting holes in the firewall.  Now by smaller I mean about a 45 inch wing span and still a good size plane.

Didn't realize that these cluttered photos were the only ones that I had at the time I posted this.

I'll take some better ones as soon as I get some time.

A couple of things that I really liked about this plane is that the builder did a pretty good job of construction and covering, but also, I see no oil residue and so don't think that a motor was run on this plane let alone even mounted.  I don't think it has ever been flown.

The first thing I looked at doing was to figure a motor mount

You can see here the holes for the original motor mount.  Fortunately the builder install blind nuts from the back side.  I just needed to figure out what size they are and how to go about using them.  They are oddly laid out so I can't directly use them and I'll need an adapter.

You can see the blind nuts in this photo.

I decided to use a circle of 1/8 inch plywood.  I would drill holes to line up with the engine mount holes and then drill holes to fit the electric motor mount.

I lined up the disk from the back side so that I could transfer the mounting holes from the front side.

Here is what I came up with.  I started counter sinking the holes so that I could use flat head screws so that it will fit flush against the firewall.

Here are the parts that I came up with to create my motor mount.  I ordered some aluminum stand offs from an online source and screws and washers from my local hardware store.  As I recall all of the threads turned out to be a standard 10-24.

Here is how the stand offs will fit with the electric motor x mount and the original motor mount.

This is how it would look with the longer stand offs.

Here is the new round plywood mount test fitted in place.

I needed to ream out the x mount slightly to fit the new screws.

Now the screws fit fine.

Here are the different stand offs and screws that I used.

Here is how it would look with the long stand offs.

This is how it would look with the short stand offs.  I like this look better, it puts the propeller closer to where it would have been with the originally designed gas motor.

I used different amounts of washers behind the x mount arms to set down and left thrust angles.

Here is the end result.

Now I need to start looking at where and how to mount the battery, ESC, and the two servos before I can get this thing back in the air.  These will be done in future updates.

Thanks for stopping by my blog.  Please feel free to post comments, good or bad, and be sure to come back and check for future posts.

$5 Durifly Ryan STA(M)

Ok, maybe it will not turn out to be $5, but it started that way.  I was browsing Hobby Kings bargain bin items and under the $0.99 bin I found all of the critical parts for the Durifly Ryan STA(M)!  I was really bummed to find out that the engine cowling and parts kits, while not $0.99, were out of stock, but I can live without those.  I'm not so much looking for a complete, complete deal here, I just want something that I can have fun flying, looks reasonably good, and relatively cheep.

So, here is what I ordered.  One set (yes, set, right and left) of wings, one fuselage, one cockpit, one rudder, and one stabilizer.  Each was only $0.99!  So, ok, this will not come out to a $5 build as I did have to pay shipping and HK is smart enough not to let you order too many $0.99 pieces without ordering something else (I had to split this into two orders!), so shipping cost me about $28, or about $14 each order.  But still, I'm only about $35 into a $150 plane, so far.

I did already add two 9g servos to the wings (about $4 each).  You can see them installed into the wings in these photos.

The really good stuff (besides the parts being CHEAP!) is that everything was already covered, all movable surfaces were already hinged with control horns and stoppers, and the rudder has the tail wheel installed.  All very nice indeed!

The not so good stuff, the wings came without the spare (that seemed really odd!).  So I had to make one using a lot of educated guessing (but I got it done).  The rudder was a little kinked about mid way, right where the balsa color changes.  I have no engine cowl.  I have no landing gear, wheels, or pants (I'll make a set but don't plan on making the pants), the cockpit section came without the dash decals, the manual (as sparse as it was) is no longer available (luckily someone posted photos of theirs on RCGroups), and the hardware kit is no longer available (this included all of the linkage, screws, support wires/string, wing mounting screws, and misc. hardware).  I will also have to provide two more servos for the tail surfaces, a 25Amp ESC, a 3530 1100Kv motor, and a 10x6 prop.

So far I have the wing spar made, the wing halves epoxied together, and the aileron servos installed.
This photo shows the wing spar that I cut from 1/8 inch plywood.  I measured the depth of the slot in each wing to come up with an estimate for it's length.  I measured the angle of the wing roots to come up with an approximate dihedral angle.  I carved and sanded until it fit and the two wing roots came together nice and flush.

I then put a liberal amount of 5 min. epoxy into each wing root spar opening and covered the root faces with a thing layer of epoxy.  Then I slid the left side of the spar (yes, it has sides to match the wing) into the left wing and then slid on the right wing onto the right side.  Then I taped up the bottom side good and flush (lower photo) and then pulled the top side together nice and flush and secured with tape (upper photo).  I left this to sit over night.

Here is what the parts look like so far.

Check back again and find out how this new project is coming together and as usual, thanks for stopping by my blog.

Please feel free to post comments, good or bad, and be sure to come back and check for future posts.

Sunday, October 15, 2017

SD Card Extension Mod, Turnigy 9X

I love the new sound mod that I did for my TG9X transmitter!  One big problem that I have with it is that it's such a pain to update the sounds!  Because of how I opted to do this mod (the way almost everyone has done it) I have to open my transmitter every time I want to update any files.  What a pain.  Then I noticed one day that it's possible to get SD card extensions.  This is a cable where one end plugs into the existing SD card slot and the other end has another card slot for you to locate somewhere.  So I hunted down the best deal (because, you know, I'm cheep) and ordered one.  So now the rest of this is a review of what and how I did my mod.

This is just the back view of my transmitter getting ready to take the screws out and crack it open.

Here is the view of the micro SD card extender that I bought.  I wanted the flat ribbon cable but should have paid closer attention to the length.  You'll see later how the length affected the install.

 Here is a closer image of the insertion end.  Looks good.  You can also see from this view how wide the flat ribbon cable is.  I might have also paid closer attention to this and found a narrower one.  What was not obvious from this view is that the circuit board material that it is made from is thicker than the micro SD cards.  While it still fit in, it was very snug and did not "click" in.  It just stays in by friction.

Here is the socket end that will have to be mounted somewhere.  It too was larger and thicker than anticipated.  I tested inserting a micro SD card and it works just fine.

Here is my radio open with the first look at where everything is and what I have to deal with.  Lots of wires from the programming cable to the jumble of wires for the MegaSound board.

This is another closer look.

And yet another closer look.  We can easily see now the micro SD slot that we will be working with.  It sure has been a pain to open my radio every time I wanted to update a sound for a new plane or option.

This view is just holding the radio programming cable out of the way to see what kind of space I have to work with.  After looking things over, I decided this would be the best location for the SD slot end to mount.  I really wanted to mount it on the side, but with all of the socket connectors (all the white ones) and the MegaSound board on the other side, it would be too confining.  So, I reluctantly went with a bottom mount.

This view is of the mating side showing how the battery box from the other half might interfere with mounting in this location.  Since it is just under flush with the rim, it should not be an issue if I stay below the rim of the mating side.

Here I have outlined the area that I need to cut out to accommodate the socket end.  I made sure that it would be clear of the stand and above the curvature and still well below the rim.

I started by drilling small holes inside the lines.  I just used whatever suitable small drill bit that I had.  I could have just as well used a larger size and just drilled them down the middle.

Here is the end result ready for cutting in-between the holes.

I just used my utility knife and worked at cutting the ribs.  It took some time but finally the center was cut free.

Fortunatly this plastic, while tough, carves nicely.  It took some effort, but was nice to work with.  As soon as I could, I broke out the files and cleaned it up and to the lines.

Here is the final test fit of the socket end.  Nice and snug without pushing in on the sides of the socket end.

Here is how it looks from the other side.  You can already see that I will have to do some folding and manipulating of the ribbon cable to get it to the SD socket on the MegaSound card.

here you can see how I started to layout the ribbon cable.  It was so long that it had to make a few runs back and forth across the radio.  I also put a ruler along the bottom stands to make sure the socket end would not extend below and interfere with sitting level.

Here it is hot glued from the back side.  You can also see how I folded the ribbon cable.  I creased it to help fit better as well.

Here I started to add some hot glue from the outside to ensure as secure mount.

Here it is all done and put back together.  I didn't think that I would be happy with the bottom mount but I have changed my mind.  I realized that if it were on the sides, my hands might inadvertently cause problem, but on the bottom, it is out of the way but easily accessible when needed.

I have already used this about twenty times as it is so easy to add and mod sound files now.  I am really happy that I did this upgrade.

Thanks for stopping by my blog.  Please feel free to post comments, good or bad, and be sure to come back and check for future posts.

Sunday, October 1, 2017

Adding Voice to my TG9X

I finally decided to install the MegaSound mod board that I purchased over 2 years ago.  I'm really happy that I completed this mod as it makes a bigger difference than you think to have your transmitter tell you something without having to look down.

Unfortunately I do not have good photos of this mod, so I will do my best with words and what pictures are available.

From the instructions on Open RC forums and the instructions that came with it, I came up with my plan.  I decided to place the board in the lower right of the inside as you see in the pictures.  This placement helped with wiring but was not optimal for the SD card.  It took a while to solder up, but was not to bad.  I decided to use wires from some ribbon cable that I had available and it worked just fine.  I did use some heavier wire for the power connections that you can see in red and black in the picture below.

When it came time to mount the board, I needed something to keep it from shorting with the main board.  I use a lot of Dollar Tree foam board and decided that would make for a good space.  I cut a piece just smaller that the board and hot glued it to the backside. Then test fit it and used some more  hot glue to secure it to the main board.  Worked well and I'm happy with it.

It was also necessary to install a new speaker (supplied with the kit).  There was a perfect place to install it behind the grill,  A little hot glue and it was in just fine.  The instructions required the removal of the mini speaker and drive transistor.  I have the needed solder iron and solder sucker so this was easy to accomplish.  The picture below shows the installed speaker and the board with the mini speaker and drive transistor removed.  There is a wire connected to the signal to the drive transistor so that the MegaSound board knows when the main board is sending tones to the speaker.

These photos show everything completed and ready to go back together.

I followed instructions that I found on Open RC forums to record computer generated voice sayings.  I saved these to the micro SD card with the appropriate files names.

I never realized how nice it would be to have audio and now I love it.

Thanks for stopping by my blog.  Please feel free to post comments, good or bad, and be sure to come back and check for future posts.

Cleaning a Dirty Brushless Motor

Some times you biff a plane into the dirt.  Some people tend to do this a lot more than others.  I think I tend to land (pun intended) into that group.  This can really mess up an electric motor, especially if you keep trying to spin the propeller (if one still exists), or the shaft.  This can cause all kinds of damage to the magnets and stater coils.  So don't do it!  If you get dirt into your motor, just leave it until you get home and can clean it.  Brushless out runner electric motors are actually quite easy to clean out.

I recently had this issue with my Hobby King Club Trainer.  I came in over a freshly plowed field and didn't make the runway.  Of course it nosed over and the cowling scooped a large amount of dirt all around the motor.

Below is how I went about cleaning it up and getting it back into shape.

The first thing that I did was to take the nose cone and prop off.  All the while being careful not to spin the motor shaft (or at least as little as possible).  Then I removed the motor from it's mount and disconnected the power connectors.

Now you need to take the motor apart and separate the out runner and magnets from the stater coils.  A lot of times this is done by removing some Allen set screws.  In my case, this was held together with an "E" clip in a slot on the end of the shaft.  There are special tools for removing these, but I usually just use a small screw driver or pick.  Just be careful not to bend or gouge up this little item or you will need to find another.

Now separate the two parts.  This is not always easy to do as the strong magnets used will try to keep the iron stater where it is.  Just be careful and don't pull on the wires!  For mine, I was able to pull on the prop shaft and the bearing tube.  After some effort, it popped right apart.  Depending on how much dirt is in your motor it may cause it to bind up.  If this happens, first try tapping the motor with the bell facing down to see if anything will come out.  Then try to gently turn the motor just enough to free it up.  Repeat this process as needed until it can be taken apart without damage to the magnets or iron stater.

Now take the bell out runner side and tap it down on a suitable surface.  By a suitable surface, I mean something relatively soft.  Don't do this on a hard surface like tile or metal as you risk damaging your tile and the shaft.  This will dislodge most, if not all, of the non magnetic dirt.

Now take a stiff epoxy brush and start bushing out the rest of the bits that remain.  I thought I would have a tough time with the magnetic bits and iron dust with such strong magnets, but they came out quite easily.

As you can see, it's nice and clean once again with no remaining bits.

Now just reverse the process to put things back together.  Be careful putting the stater back into the out runner bell as it can come together quite violently and pinch fingers!  Once it's back together make sure that it spins freely again.  Of course you will still get the "coging" of the magnets and stater, but there should not be any grinding or gritty feel.  If you do encounter this, start over and clean it out again.

Argh!!! It happened again!

You can see that the mud actually mushed all the way through the motor.  I pulled everything apart and used some water to rinse most of the mud off.  Then I made sure that it was dried out to make sure it did not rust and then used these techniques to clean it out the rest of the way.  And yes, it did fly again.

Thanks for stopping by my blog.  Please feel free to post comments, good or bad, and be sure to come back and check for future posts.