bcrc

My Feedback: (19)

Ty:

What would you or Darrell suggest to reinforce the nose section? More fiberglass? Wood or carbon fiber formers running from firewall back?

The front end seems solid to me. One possible problem would be that the firewall is not glued in properly -looks like they just put a
bead of glue around the perimeter of the firewall on the front side. I can't tell if there is glue in the actual joint.

Brian

fockewulf37

My Feedback: (102)

Personally I am putting a cockpit in the one I have. Before I install it I will just reinforce the area with some 1/8" balsa glued/Epoxied to each side . Maybe a 4" wide piece that has been cut to exactly fit between the bulkheads. That will really strengthen the area. You could also use some carbon fiber glassed into the sides.. That bead you see in there is a bead of fiberglass and something like cabosil It should not ever move...

Ty

bcrc

My Feedback: (19)

Ty

Yes, I tried to grind out some of that stuff in one spot and it was really tough. It has fiberglass strands in it.

It sure would have been easier to put carbon fiber or wood reinforcement strips down the sides if it were done before the bulkheads went in! Then it would have tied into the bulkheads at the nose gear area and the firewall area and at the wing area with one unbroken piece- it would have been super strong. I will do what you are doing - put reinforcing material between the bulkheads on each side.

By the way, the fuselage is made with polyester resin (I can tell by the smell when I cut it), which I use as the glue to glue anything to the fiberglass fuselage. I did a test on a piece and it holds much better than epoxy glue. I did the same test about 30 years ago when some of the planes had an epoxy base and some had a polyester base - with the same results. For the polyester ones, polyester resin holds much better than epoxy glue. I am using Bondo from the local auto parts store, but the stuff Sig sells at the hobby shop is fine also. And you can control the setting time with the number of drops of activator.

Brian

bcrc

My Feedback: (19)

I have an ESM DO-335 and have been working on it for a couple of weeks. I'll send in posts of my progress that might help someone else or me.

Since no one has flown one that I know of, and ESM and its dealers do not have any video of it being flown, I am initially going to build it "on the cheap". By "on the cheap", I mean I will not be investing any more than is needed to safely first fly it. When it flies and flies decently, I will finish it up. I already own the engine and radio components. So my expense will be the cost of the ARF, and probably about $100 - $150 for hardware (I expect to use little or none of the hardware that comes with it - I hardly ever do with ARFs).

I will be initially building it with fixed gear. After it flies, I will buy the Sierra retracts and wheels for it.

I will be using an OS 55cc gas engine in the front, and nothing in the back. The OS 55 drops right in with the correct spacing from the firewall to the spinner backplate. After it flies, I will consider options for the rear.

The fuselage is very nice and the paint is great. The wings and empennage are covered with some clear iron-on that the paint does not stick to as well as it does to the fuselage. Again, after it flies well, I will strip the covering from the wings and empennage, balsa sheet all openings, glass them and paint them. Model master paints match the existing colors well.

I have been taking photos of my progress so far. I will do each subject as a separate post - with photos and comments.

bcrc

My Feedback: (19)

Servo Hatches, control horns, and hinges:

For some reason, the servo hatches on the stabs and fins were about 1/4" too small in each dimension for a standard size servo. The ones in the wing for the flaps and ailerons were slightly bigger and were fine. I have no idea why they did this, as it couldn't be to save time or money. It would be just as easy for them to make them so a full size servo would fit easily. I spent several hours making my full size servos fit. The depth was no problem, except for the bottom fin, where I had to "hog" out the opposite side a little bit. Also, so that I wouldn't have to move the slot for the servo arm, I used Air Wild's MLP arms - they position the arm lower down on the servo. I didn't use the servo mount blocks that came with it I replaced them with hardwood - I don't like whatever came with it (too soft) - I think it is bamboo.

I also found that there were no hard points for mounting the control horns. Any horn you used, including the ones that came with it, would have quickly come loose in the balsa. I used Du-Bro's large horns that I like. I glued 4 short pieces of hardwood dowel into each surface (rudder/elevator/aileron/flap) below where the screws for the horn would be. Each piece of dowel went from the surface to almost (but not quite) the other side. Then I drilled a hole down the middle of the dowels and installed the horn with 4, #4x5/8" screws. This worked quite nicely. There were 32 of them to do, so it took a while !!

I didn't use CA hinges as they show. I used my favorites: Hayes (P/N 105). I've been using them for 35 years - since back when Kraft and Hayes were together. Best hinges out there. Be sure to sand them and pre-bend them before installation. I wish they made these bigger for really big models. I have several 50cc aerobatic planes using these hinges with hundreds of flights. However they aren't big enough for airplanes bigger than 50cc.

Brian

jimkron

Hey Guys,
I made a little video of my motor setup. I know most will be going with gas like Mr DJ, but the electric is pretty cool as well. I put the front motor into the throttle channel and the back motor into channel 4. In my JR9093 I mixed the two with the throttle as master.
What do you guys think about reversing the rear motor and running a regular prop? Is there a Torque problem having the two motors spin the same way?

Enjoy the clip...it's not fancy.

http://www.youtube.com/watch?v=HtNRA0tfyk4



jim

Mr DJ

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bcrc

My Feedback: (19)

Making stabs and fins removable:

I wanted the stab/elevator and fin/rudder assemblies to be removable. Now, if I ever move, it might fit back into the box it came in !!

To do this, I got some 1/2" ID Phenolic socket from Graph tech. The aluminum tubes will be a little sloppy in the socket. To make the aluminum tubes fit tight in these sockets just wrap a few layers of packing tape around the tube - just keep adding a layer until it fits tight in the socket.

Hopefully, the photos explain it all. Please ask if you want more details on how I did anything.

bcrc

My Feedback: (19)

DO-335 insanity:

What is a DO-335 multiplied by two?
It is a DO-635 (I didn't do the math)

Imagine the sound: 4 Daimler-Benz V-12 engines ripping by.........

Ram-bro

My Feedback: (101)

here are some pics of the cockpit panels. I will post pics of my Al Masters 335 later. They are it appears the same size/scale and so of course I am lurking tosee what I can see and learn from you all

fockewulf37

My Feedback: (102)

I am working on the instrument panel right now.. Sorry mine will not be as detailed as that one . Can't pull that out of plastic. Trying to make it one piece.. Anyway.....

Jim, good Video. You may want to check. I had planned on putting the rear motor Batteries in the fuel tank position and then the speed control and then just lengthen the motor wires. Yes that will be a little over 12" to the motor but I don't believe that hurts anything. Its the distance between the battery and speed control that is critical .. I have run this setup in an Me 109 with no cooling over the speed control without any problems or overheating... Just a thought..

Ty

jimkron

Agree Ty. I'm just guessing where everything will be...finding the perfect CG, cooling for the ESC, cooling for the Batts, and keeping the wire length acceptable make this setup a challenge for sure. Right now I'm roughing in the plumbing.

Jim

fockewulf37

My Feedback: (102)

I think you will have better than 1 to 1 power. You will be cruising around at about 1/2 throttle most of the time...

ty

Mr DJ

Jim,

Excellent video... U look just like I pictured U
Man, those electric motors are lookin' and sounding pretty nice. And the non-mufflers are a major plus. I'm almost tempted

Mr DJ

bcrc

My Feedback: (19)

Jim:

I saw your video. The lack of a head and mufflers sticking out really makes me want to switch to electric also.

What are you using for:
Front motor
Front prop
Front speed control
Front batteries
Rear motor
Rear prop
Rear speed control
Rear batteries
???

Will the front motor fly the airplane with the back motor out/off ?

Please explain in more detail what that capacitor is for in the rear.

Thanks,
Brian

fockewulf37

My Feedback: (102)

I have this same setup in a 18lbs Me 109. It has plenty of power. It turns a 21x10 APC prop at about 6000 rpm. I am getting 6-8 minute flights with good throttle management. On the Do335 2 of these would be way over powered. You would be able to cruise at about 1/2 throttle. Wide open should be greater than 1 to 1 on power. I fly the 109 on older 20C batteries. With the newer 35-40c batteries there would be even more power. Batteries have really come down on cost. You can find 160's online for about $125 now and then .. I bought my last 2 for $100 each.. You need at least a Castle Creation 85HV speed control for each motor. I may be wrong and sure will be corrected if I am. I Don't really think you need the capasitor in the rear if you put the Speed control within 12" of the speed control and just make the Motor wires a little longer. In the rear with the batteries installed speed control in place your wires from the speed control to the motor would only be 16-17" long. I don't think that would be an issue. you would rarely need full power with this bird...

Ty

Mr DJ

Ty,

With the Sierra gear and 5" wheels installed, what is the largest prop that can be used? 21", 24", what?

You know I'm a gas man, but those electrics with no disturbed cowl is lookin' somewhat nice.

Mr DJ

jimkron

pandissix

My Feedback: (134)

Jim. Great video.

The question about the capacitors and why we use them. On my 262 project I learned the hard way that without them you can blow the capacitors on the ESC when you connect the batteries on long leads. In my case I had over 24 inches in leads. I blew up 2 castLE HV110 making that mistake. In sum the capacitor acts like a sponge to absorb the energy wave that travel down the lead. The longer the lead the bigger the wave. During my testing I only had a 5 amp drop in power when using them vs no capacitor. They are a must in this type of application.

fockewulf37

My Feedback: (102)

There is a guy flying a ASM B-17 with his setup with all the batteries and speed controls in the center section of the fuse and long wires out to the motors and he is having no problems. His wires are way over 17" to the motors. It the length from the batteries to the speed control that is the real big issue. They say there can be some power loss with long leads to the motor. but with what we are looking at here i don't think there is a big problem...

Ty

jimkron

Thanks on the video.
Does anyone sell large Cap (5000 microfarad) for RC use? I found one on line for a computer that was 5 inches long.[&o]

jimkron

Most of my angst is about CG. The wires on the motor and esc total 10 inches. I added another 10 inches to get the ESC in the middle of the scoop. The esc has about 5 inches of power wire. I'm guessing on the balancing, but the Batts might need to be another 6 to 12 inches more towards the nose...not sure at this point. Wouldn't it be nice if those batts need to be right next to the esc.
Sigh...
jim

fockewulf37

My Feedback: (102)

Hey here you go : saw this this morning:

http://www.rcuniverse.com/market/item.cfm?itemid=718737

Ty

Bluffman

My Feedback: (1)

That was a great explanation on the motor set up Jim, thanks for taking the time. Ian

kahloq

You can get E-flite 160 size motors for quite a bit less expensive AND they work just as good.

Hobbyking has the Turnigy easy match G160 for about $50
http://www.hobbyking.com/hobbyking/s...dProduct=14408

and Hobbypartz has the Exceed r/c MonsterPower 160 for $49.70
http://www.hobbypartz.com/mo1602brmo.html

Ive got some monster power motors and they run well. Same with the newer turnigy motors.