Excuse me... I've got Gas! Trex 600 Helibug Gasser

[Doozer]

I think you have to use a 90 frame but I found this. Its a couple of years old so there may be more... just the first I found. That's pretty quiet.

[Solitaire]

Yeah, I can see a 4stroke would be a bit large and heavy. OK, I guess, if you're just toodling around. You just can't beat a 2stroke for quick revs.

[Doozer]

I attempted a maiden... attempted.... It kept spinning and spinning... I was like "wtf." "It was moving the right direction earlier. It was set up in rate mode." I cut out my bad language and the trips back and forth up the street. That didn't leave much video. When I finally got it back to the table, I checked the rx, and there was the problem. The gyro had come unplugged. Now I'm a bit worried. On a positive note, it starts very easy. Here's the video:



There's still some stuff that I plan to discuss in the build notes, but the pictures are all up. I lost, or deleted my dial indicating photos. I'll start another thread at some point then link it in this one. Reducing vibrations is a must with gassers and if you don't try to get rid your vibrations, parts will start falling off.

[Doozer]

I've added a section on Throttle set up both mechanically and in the radio. I also added how I have my pitch set up.. mechanically and in the radio. I didn't cover how to set up pitch curves because there are numerous posts, sites, videos, podcasts, magazine articles that cover that. Easy to find if you don't know how. Check my "Small but Potent list for beginners" thread in the beginners forum if you don't know where to start. It's a valuable resource for beginners but it's buried on the second page so you'll have to look for it. Or better yet:

www.rchelitalk.proboards.com/index.cgi?board=coaxial&action=display&thread=3619

[Solitaire]

Nah, no searching on page two...we'll just sticky it.
Sorry, Dooz, missed that one. And I try to read 'em all. ;D

[Doozer]

May 16, 2011 19:09:32 GMT -6 Solitaire said:

Nah, no searching on page two...we'll just sticky it.
Sorry, Dooz, missed that one. And I try to read 'em all. ;D

No worries man, I've just been seeing a lot of questions that could be answered directly from that list.... not that I mind answering if I know, but sometimes exploring leads you down a path you never intended to go down. You end up pleasantly surprised.

Well.... there wont be a maiden any time in the next couple of days. The OWB is fouled and the spark plug is wet. The one way went during spool up, and I took the spark plug out to try and clean it, but it still doesn't seem to be firing. I'm going to run to home depot tomorrow and pick up another one. Cheaper than a glow plug and I can go to the hardware store to pick it up... Nice. The only issue is... How did it get that way. I've set the engine up by the book 1 3/8 turns on both needles. $4 bucks is cheap in this hobby, hopefully that will fix it.

[akent]

Yes, that was a great post with lots of great info!
Thanks for the sticky, Sol!
====
I have a number of gas motors like that in garden equipment. One pull too many with the choke on will flood em.
At least I hope that's all it was!

It's going to be fun to see that in the air, Doozer!
Kent

[Doozer]

just got back from O'Reilly Auto parts. Got the exact same sparkplug for $2.75. That was the ticket. I pulled the gears, the one way is good, which means it could be a clutch issue. The manual, as well as others that have built this kit, talk about installing a Lynx gas clutch liner. I have one, I just didn't install it. I wanted to see what would happen. I'm going to pull the clutch and see what's up. I'll take some pics and post them.

Edit: I wanted to add that I took steps to make sure I don't foul another plug. Needle settings on gassers are far more sensetive than nitros, off by just a little bit and you can get yourself in trouble. I was priming, when I didn't need to, and I was also running somewhat too fat. So I went out on the High needle to 1 5/8 and in on the low needle to 1 1/4. I'll see where that takes me.

[Doozer]

Added a how to check the spark plug turtorial to the original build post.

[Doozer]

Added a dial indicating video.

[The Dude]

Noice, I love it!

[Doozer]

Man... I really got lucky. I put the screws in the one way hub in wrong and this caused the hub to spin inside the gear, leaving a grove inside the hub mount. It also made me think that I fouled my OWB. Luckily it didn't ruin the gear. Also, you need a spacer in between the clutch bell and the pinion. A washer from the one way sleeve pack is perfect. The manual recommends this, again, I didn't do it. Without it, this causes the bottom of the tail drive gear to rub the clutch bell, and the clutch bell sits higher so it takes more rpms to engage. Why didn't I do it? I was high from gas fumes and forgot. Which reminds me, don't work on these gasssers in the house with the gas tank attached.

So... theres the mistakes, and they are all fixed. New plug, screws in the right way, and a spacer between the pinion and clutch bell. Too bad it's dark. I'm going to try and sneak in a hover between work and the gym. I'll take a picture of it now and add it to the build post.

[Doozer]

I'm going to keep chipping away at this build over time as I see the need to, but I'm going to stop adding new posts unless I make a major change. So this will be the last sort of update until I maiden, then I'm going to make subtle changes to the build post. I'd like for the build to be able to help someone build the heli, not confuse them. I don't think its there yet.

I was upset about the dial indicating video. I had to shut my garge door and my bench light was out. I wasn't looking through the camera so I couldn't see the glare on the dial indicator. I'm not sure when I'll have another chance to do that again. I'll fix the video when I do.

...and what do ya know, I made some time to fly this afternoon and it rained. Outside of monsoon, it rains about 4 or 5 times a year tops. I think it was an omen... a sign. I'm being told.... don't fly this heli with those woodies you cheap bastard. I probably shouldn't. Much past 30% throttle and this heli sees some serious head speed. I need a rev limiter for sure. I'll pick one up this payday. Maybe I'll add a rev limiter install to the build.

anyway... that's it for now. When I maiden, I'll post it.

[Doozer]

Some Major changes made to thread:

1. Added a break in video complete with radio curve changes. I was getting a fair amount of bobbing and slight oscillation in the head with the lower percentages in the throttle curve. My curve percentages are now, 0, 15, 30, 35, 37.5, 47.5, 100.

2. I had taken my low needle in some to about 1 1/4. The engine started getting hot and sagging a bit, suggesting a lean condition. So I took it back out to 1 3/8.

3. I started with a CC 10A BEC. I removed it because of issues I read about, and one person on the HF forums suggested 10A wasn't big enough. I switched to the stock ESP BEC but that died. So I mounted the 10A BEC again after assurances from friends, and an email to CC. While I'm sure it would have worked, it did get rather warm. This was enough to completely sketch me out, so I bought the CC BEC Pro. Neither the battery nor the BEC get remotely warm now. I'm satisfied this was the right move for me, but I'm fairly sure the 10A BEC would have worked. It would have made me stress while flying though.... I added pics to the build post showing the new installation.

4. The woodies were coning. So I put Align FRP's on for break in. Break in is going to be a long process. 8 oz at a time at about 25 minutes a tank. That's stopping to adjust curves, trim, temp, etc. etc. I'm sure the times will go down the further along in the process I get, but for the time being, I'm proceeding cautiously. Though a bored out TRM G240 sounds nice Anyway, I don't think the woodies were going to cut it. This bird loves high head speeds, and I would not have been comfortable flying with wood!

I'm not planning on drawing out this thread. I want most of the information to be on the first page. The first two posts are dedicated to the build and the third will be break in, maiden, and flight videos. Thanks to Sol for the cool image editor, so I'll be getting some side by sides up soon. Keep checking back now and again for changes, but at some point I'll be finished. I'll let you know when that is. I am considering a Frenzy 90 gasser......

[Doozer]

Added some break in and tuning info. Taking inventory of my electrics and parts.... look for some For Sale items in the near future. Getting out of electric and nitro. Gas is where it's at! Cheap fuel.... long flight times.... clean burning fuel... cheap engine parts... more quiet than nitro if tuned properly... better parts availability... more power than most of us will use... can run on camping fuel or gas (if gas smell bothers you, use camping fuel)....

On a price per flight cost.... hands down, not even close, gas spanks nitro, and beats electric.