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Posted by earlwb | 11-06-2019 @ 10:56 PM | 5,270 Views
I thought I ought to add a new blog entry as I had not done one in quite a while now.

This is my Giant Big Stick from Tower Hobbies. I electrified it with a huge Turnigy 63-74 200kv brushless electric motor. It uses two 5000 mah Lipo battery packs in series for 8 cells total. The motor was popular with the electric skateboard and scooter people a few years ago too. It doesn't rev up all that high so I use a 18x12 propeller on it. It doesn't draw a lot of current per se, around 80 amps full throttle and cruises using around 40-46 amps.

I put the servos in the tail as I didn't like the idea of using real long pushrods with it. But to avoid adding a lot of lead to the nose, I opted to use the motor box and mount the motor farther forward.
Posted by earlwb | 05-24-2013 @ 09:43 PM | 16,236 Views
I recently got lucky and was able to acquire a Evolution 58cc liquid cooled gas engine to my home stable. Of course now I have to come up with a use for it. But I have wanted one for a long time ever since I first found out about them. The engine is just so nice being a MVVS product. But the water cooling is great as it allows the engine to run better with more even and controlled temperatures that don't vary wildly like they do with air cooled engines. The 58cc gas engines develop some awesome power and are downright spectacular with a tuned pipe of course. I just think that the MVVS or Evolution liquid cooled engine has to be the ultimate in a RC model engine.

Anyway now to decide what to get to mount the engine in. I saw a fellow who put one in a Giant Revolver and that looked really promising. But maybe a 50cc size P-51, or other type of Warbird would be more nice, hard to say.
Posted by earlwb | 05-20-2013 @ 11:45 AM | 13,404 Views
A while back I came into possession of a Evolution 58GX gas engine. This was one of the earlier versions with two magnets on the drive hub and a old style Valach CDI unit too. First the Valach CDI unit had the power input pulled off. I am planning on using the engine in a giant size Great Planes Aeromaster Biplane that I got too. It just fits inside my car so it'll be the biggest plane I will be flying later. I am somewhat limited as to how big of a airplane I can fly by whether I can fit it into my car or not. I do have a Subaru Outback and the rear seats fold down flat so it does have a fair amount of room in the back of course. But even then it is still limiting as to how big something can be to fit in inside.

I first decided to see if I could fix the Valach Ignition module or not. That actually did turn out well and I successfully repaired the Valch ignition unit and test ran the engine using it. But then I found out that these earlier Valach units weren't all that reliable and that many people had problems with them. Plus you had to use a special spark plug with the top cut off along with the special spark plug cap and a thin wall deep socket if you ever wanted to change spark plugs.

So I decided to convert the engine over to use the CH-Ignitions module instead. The conversion turned out really well too. It has a nice metal timing sensor holder and since the hall effect sensor only detects one of the magnets (one magnet is north pole oriented and the other magtnet is south pole oriented) it was not a problem to get it setup.

I used regular pump gasoline from my local gas station. I mixed it with Stihl Ultra oil. I was running a Top Flite 24x10 propeller on the engine. I was getting around 5750 RPMs with that combination. The muffler is not very good as I measured 102DB using a iPhone DB meter app. According to Pe Reiver's Prop power calculator spreadsheet application the engine was developing around 6.5 hp.

The Engine from when I first got it:

Here is the new CH-Ignitions timing sensor holder mounted on the engine:

The CH Ignitions module compared to the Valach module:

Here I am test running the engine to see how it does using the CH-Ignition conversion:
Posted by earlwb | 11-24-2012 @ 10:25 PM | 15,131 Views
I have had this World Super Stunts .60 plane for a couple of years or so, but never did anything with it. So I decided to use it. I put it together and used a Futaba FAAST radio system with all S.Bus servos as well. The CDI unit is powered by its own separate 2200mah LiFe battery pack and the radio uses the same type of LiFe battery pack too.

The engine is a NGH 17cc gasoline engine using a 14x8 propeller on it. it turns out that the engine worked really well and has ample power to fly the plane, albeit no 3D hovering by hanging off of the prop much though. But once the plane is airborne I can throttle back to about 2/3 throttle and the plane will do all the normal aerobatics quite well like that. 1/2 throttle or even 1/3 throttle is a good tooling around speed too.

The plane is pretty huge with a 80 inch wingspan. But it is built really light though, so overpowering it isn't a good idea, unless you go in and reinforce it a lot. It'll fly fine with a good .60 to .75 size engine on it too. I tried some different engines and none of my regular 1.20 or larger engines will fit in between the motor mount rails. So unless you change how you want to mount the engine on the firewall, the larger engines aren't going to fit. Also it doesn't have a fuel tank hatch so changing the blind nuts and where they mount would be a hassle too. So I decided to just use the NGH 17cc engine as it fits in the plane easily and is easy to hook up too. It isn't much different than running a glow engine on the plane.

I did put the elevator and rudder servos in the tail at the rear though. I like that method as it makes for a solid way to control the control surfaces. Since the plane is so long, using pushrods, etc for all of that length would tend to have problems with flexing, etc. I did use a second rudder servo for the nose gear though. it fit right in next to the throttle servo. I also didn't use all of the hardware that came with the plane, opting instead to substitute pushrods and clevises as needed.

The plane flew great. The engine had more power than I needed to fly the plane. But not so much as to be overpowering the plane though. I have been pretty impressed with the NGH 17cc engine. The Walbro carb on the engine has been the best carb of that type I have used so far. The carb came pretty much set good right out of the box, just a little rich on the main jet and that was it. But the transition and throttle response has been great, and no dead spot where as you advance the throttle and the engine would tend to lean out as it changes from the low speed to high speed jets.

Trying to land the plane without using the flaps is tricky as it has so much wing area in comparison to its weight, that it'll float and tends to not settle down under the ground effect when it gets close to the ground. So you either need to come in at a higher alpha angle mode for landing and or take advantage of the flaps to help slow it down too.

My plane came out weighing in at about 9 and 1/4 pounds so it isn't heavy. I even added 6 ounces of weight to the nose of the plane that I probably didn't need, but I was concerned as to where the instructions stated the CG was. So I added the weight to move it forward some more. One could build it more light using a glow engine and putting the servos where the instructions state too.
Posted by earlwb | 09-20-2012 @ 07:01 AM | 12,472 Views
This is the biggest plane I am flying at this time. it is a Aeroworks 80 inch profile Extra. It is actually quite fun to fly and it still has a light wing loading even with the ASP 1.80 engine on the front of it.
I also tried out the Futaba s.Bus system with this plane, where I used the newer Futaba dual s.bus receiver as well as five S9072 s.Bus servos. I used a standard S3004 servo for the throttle. Since I don't fly it full throttle much, the 16 ounce fuel tank has been adequate for flight times.

I made a couple of videos of me flying the plane as well.
This first video was made using a camera that has something like a fish eye lense, which I don't like much.
Flying my Aeroworks 80 inch Profile Extra RC plane (8 min 17 sec)

this second video was made with a camera that had a better lense on it
Aeroworks 80 inch profie flight video m4v (7 min 48 sec)