Reactor Bipe w/ DLE 20

[19000rpm]

I look forward to that vid.

[Doozer]

All done. Posted up some pics in the build thread. I was going to try and make a movie, but it got too late, and the canopy glue hasn't dried yet. Definitely tomorrow though.

[19000rpm]

Nice finish to the build.

I noted your use of 30min epoxy. I need to have that on hand for longer assembly times. 30min. is supposed to be stronger than 5min as well. If that's a factor.

[Doozer]

30 minute Epoxy can seem like a hassle in some cases. However when I used to shape surfboards you could make the resin "Go Off" faster by adding more catalyst. However, the drawback was that it got hotter, and made the resin more brittle. It also caused the resin to yellow quicker.

These things vibrate a ton, especially with the gas engines. Having something a little more flexible just makes sense to me. I did use 5 minute epoxy in some places, but 30 minute epoxy gave me a little more time to screw around ;D

I posted up a price out, and I'll most likely get a video up at some point today.

[Doozer]

Video is up in the build post.

[19000rpm]

An ambitious project that has turned out well! Very nice and complete build log. The video came out well too. Now for the maiden!

I noticed your comment about adding extensions to your servo leads. If you do that in the future make sure you also use a servo connector keeper. I will keep your servo connectors from coming unplugged from vibration etc. A real factor to consider. Can't find a link to any, but your LHS should have them.

Again, great job!

[Doozer]

Thanks for the kind words 19. Coming from you that means something.


Well... I've found a problem already. While setting up my rates in my radio, I noticed that one of the Spektrum servos (H5000) worked while it had resistance on it but once I let go it became "notchy." So.... I'm going to replace the 3, because they came out of a heli I flew a lot. I'm not going to replace them with the Hitec minis, but with Hitec standard metal gear servos.

The reason I want to replace them with standards is that my CG is a little nose heavy and 3 standard servos right in the tail should balance it out. If it becomes tail heavy I have enough of the stick on weights to even it out. I'm going to get the servos Friday then start the change out as soon as I get home from work. It's going to be very pleasant next week and I'd like to get it in the air Monday or Tuesday.

[19000rpm]

That's a good call on the servos. I always use MG servos on the tail when there is going to be heavy loads exerted in aerobatics etc.

I don't know how your throws are set up, but for your maiden I'd go with 60% low rates and 25% expo for elevator and aileron just in case high rates are too extreme. That can catch you off guard on a new plane.

[Doozer]

I'm going to go over my curves and rates in the build post but that's right where my throws are set up. Elevator is at 62% and l left the expo linear, but I see your point having some expo. I have 30% expo on the rudder just because I don't want to over steer. The high rates are outrageous. I don't think I like them where they are at. I mean the recommended high rate for my rudder is 89mm of throw (3 1/2")... I'm over-driving the rudder servo to 120% to get that. Couple that with double the power of the recommended engine..... I think that's pushing it a little.

Anyway, other than the tail servos, and the fact that the engine needs about another hour of ground break in time, I'm feeling pretty good about this one. I've been running the low needle a little rich and it's not idling all that well. So I'm going to close the low needle and open the high up a bit to compensate.
As soon as I get the servos installed and the engine idling perfect, I want to get it in the air.... Hopefully by Tuesday.

I'm not all sketched out like I was with the Pitts. Last night I was sitting in a lawn chair breaking in the engine. I was holding the tail with my hand and at 1/3 throttle this thing was hard to hold. I could probably hand launch it vertical ;D I kid, I kid, but it really wants to fly. I can't wait. The only reason I say hopefully by Tuesday is so my son can shoot the video.

[19000rpm]

It looks like you're as ready as anyone is for a maiden. We'll be waiting to see that video Tuesday night.

[Doozer]

Pulled the H5000's and added 3 Hitec HS645MG's Funny thing is the balance at dead center of the balance point was 3/4 of an ounce nose heavy. ::shrug:: I thought it would be tail heavy for sure. I triple checked the results... I'm thinking it's one of two things. The balsa I cut away compensated for the heavier servos... or.... I screwed up the first set of measurements. I'm pretty sure it's the latter unless that was a special kind of balsa.

Also, I got the engine to settle into a nice idle. I reset the needles to factory settings (1.5 turns out each). I took my time and made each turn precise then opened the high a hair and closed the low a hair. That's the American standard unit hair and not the European metric hair. So I guess I had the low needle out way too much.

As usual, there are varying opinions about how to break this engine in. The manual says two hours. I've also read two gallons. I think they are both correct. In two hours you can certainly get the engine running well enough to fly and land, but you won't be producing the same amount of power as an engine with two gallons through it.

On four ounces of fuel I went for 40 minutes fluctuating between idle and 1/2 stick. I understand this does not simulate flight times but its a good indication that it's going to sip fuel.

Fun day. I look forward to Tuesday.

[19000rpm]

Triple checking something like CG is never a waste of time. In particular after component changes and/or re-locations. I had a similar experience when I put a different ESC and EDF in a plane. I was surprised at the result. Where I thought It'd be tail heavy, in reality, it became nose heavy. After moving stuff around; I checked it over and over and then right before I flew it. And it flew perfectly. Another case where never taking anything for granted paid off.

You're going to have fun on Tues!

[Doozer]

Struggled a bit last night with the idle.... again. It sounds like I have an air leak somewhere. It will idle fine for a few minutes, then all of a sudden I'll get some extra rpms without any stick input. That will happen for a few minutes or until I shut down and make a needle adjustment. I'm going to let it break in a little while longer, and if it continues I'll start to try and hunt down the issue. My plan is to one by one try different things including installing a new plug, checking the exhaust gasket and screws, mixing up some fresh gas, and if I have to, removing the filter between the tank and the carb.

[19000rpm]

I like your methodical approach to troubleshooting. You'll find out what it is.

[Doozer]

I've been doing some reading today, and it seems there's a lot I can try. As a last resort... and I mean a last resort only, I'm going to try and reset the timing for 28⁰ before top dead center. I've never done that before, but I've watched a video or two now. I linked one in the engine tips thread. It doesn't seem that difficult, but that's usually where I'm wrong.

I still think letting it break in some more may do the trick, but I didn't have this trouble with the DLE 30. So.... we'll see. I'm going to break it in for another hour or so tonight, then put it in the air tomorrow unless something goes horribly wrong.