Old Oil Soaked Demon
 

Funny how this plane has sat for a few years waiting to be re-covered...
That's all I figured on doing.
It had suffered a few bad launches and had some pretty lumpy repair work.
It had a fuel tank leak...enough that the plane was still wet under the covering.
It had a tuned pipe pumping oil spray into an elevon hinge gap.
It was time to cut this one up and use it for templates.
I've got a good running Sport Jett .46 for it.http://www.rcuniverse.com/forum/atta...mentid=2128969http://www.rcuniverse.com/forum/atta...mentid=2128970

It feels good to be working on a .40 sized plane again.
The engine and radio gear that was in the oil soaked rig look to be in good shape so all I've got to do is glue together enough balsa to hold it all in place.http://www.rcuniverse.com/forum/atta...mentid=2129251http://www.rcuniverse.com/forum/atta...mentid=2129252

Looking good Chuck what prop are you going to be running?

Looks like a 9-8 to me..? They are often the fastest or near to it on the SJ engines on sport speeders. I also had very good performance from 8.8 x 8.75 and 8.8 x 9 trimmed to around 8-3/8 on the SJ50. Weaker on launch but a bit more on the top.

CP if you need parts PM me..

http://www.rcuniverse.com/forum/atta...mentid=2129357Yep..9 x 8...! It runs so strong with the 9 x 8 that I bought bags full of them while they were cheap. They're still cheap today, but oh well.
MJD, I could use a RADIO COMPARTMENT HATCH ASSY LOW RISE if you have any in stock...?
This plane is a replica of a Demon...taken from drawings and photos posted at this forum. different enough that a true Demon Aficionado could spot the differences up close.

It's pretty much the same shape - Demon enough. After looking at the picture, you can make yer own hatch there buddy..

After the several engine combos I have flown on the prototype, the SJ50 [or .46 just the same] is still about the most *****in' all-purpose power plant you can put on one.

I assume the maiden flight will be tomorrow sometime based on past experience.

For this one I'm making an effort to have a thinner airfoil up front.
I think it could be ready to fly by next weekend.
I'd like to finish it in a metallic silver / UFO marking theme, but I'm afraid of orientation problems with that idea.
The SJ engines don't need a very precisely set needle to roar. They tolerate richness real well and I try to set mine for a thick smoke trail. I've also run it on 0% nitro and even though there was a drop off from running 15% nitro, it still ran decently. I don't throttle this one, I use a feed line pinch to kill it.

Yeah, silver sucks for orientation, I tend to think a thin delta is the wrong place to express that particular artistic inspiration.

What with venturis, open exhausts and whatnot.. where's your Dynajet/HK Red Head? Seems a natural for you. The PJ Demon design is almost done, and I'm off to test the breadboarded fuel system now as a substitute for flying anything in our 40mph gusts and rain.

The 90 acre hay field I've used all these years is finally getting developed and my nearest alternative is about the same size field but with a housing development along the eastern line and the Sheriff's HQ to my back. I don't know who owns this lot, either........
If something ever went wrong they wouldn't have far to get me.
I really need to find property in the High Desert east of the mountains to feel safe about running the FAI .40 or a pulse jet.
If you exercise some restraint and only fly these deltas in a gentle speed pattern, orientation isn't that big of a deal with me, but I can't allow myself to lose eye contact to even swat a fly.

Yeah, I know you have some field issues, just pulling your strings. I still say it's a match made in heaven.

There is always the possibility of moving to The Mojave or Rabbit Lake...?
Actually the thing to do is make arrangements with existing RC clubs in the desert and have a dedicated camper / RV type vehicle dedicated to weekends of flying.

Here it is with about a almond sized blob of Bondo spread over the low spots, sloppy seams, inside corners...
The hatch I wanted to be "springy" so that it would form tight to the arched radio compartment opening.
It has a bottom 1/16" thick sheet of basswood that runs lengthwise to the opening and cross grain balsa filler glued on top.
Next are the fins. I want them to be flutter proof, but not too thick. I don't care if they're a little heavy because these planes need tail weight anyway.
What does a Factory Original Demon use for the dorsal fins..?
In the past I think I've used 1/4" or 3/16" balsa, airfoil shaped,http://www.rcuniverse.com/forum/atta...mentid=2129585http://www.rcuniverse.com/forum/atta...mentid=2129586http://www.rcuniverse.com/forum/atta...mentid=2129587 then covered with 6 oz cloth on both sides followed with lighter cloth for a smoother finish.

If your going for the UFO color, for looks could do clear plastic vertical fin folks will only see from their cars
some sort odd flat triangle shape in the air fearing the Lil green men are scouting for the mother ship. :p

1/8" fins are stock. But.. not contest grade obviously. I always glass the tip fins. The center fin stock design is lower aspect ratio and in less peril as 1/8" stock. Your thicker airfoiled fins with glass will be plenty tough and just as clean IMHO.

I made a couple of hatches with 1/32" ply base for toughness, and cross grain balsa on top for bendability.

Yes PS, just the right thickness of plastic fin would be light enough and stiff enough. When you are flying these in bad light or too far away it might be catching just the glimpse of a fin that saves the day though. !

MJD, thanks for the info. Your 1/32" ply base hatch sounds lighter.

I brought this one down from the rafters to copy the fins. They look like the standard fins that MJD provided with FG added.
Underneath all the dust sits a plane that was immaculate before getting put away some years ago.
This little sucker ended up weighing quite a lot with titanium servos, aluminum engine mount, FG reenforcing, cowl work, etc. It's amazing how it ever launched with 7 x 7 props, but it would sink after release and slowly start grabbing enough air to flyhttp://www.rcuniverse.com/forum/atta...mentid=2129688http://www.rcuniverse.com/forum/atta...mentid=2129689. The launches never had any more force than a pizza gets when it's shoved into an oven.

That thing's gonna scream!
Hey, I hear you guys are going to lose your flying field? Sorry to hear that. I have a buddy who flies giant scale stuff there and he is sad that it is going away.

At it went 5mph faster than any Demon I have clocked so far. But I never did take the .67 out this year. I am determined to make a somewhat universal IC delta chucker this winter, something 5-6 feet in length with latex bungee on turnaround pulleys, and a foot pedal for release. Lekkie launchers are a bit easier with the prop not spinning..

Steve, I was the only flyer at the hay field I lost..except when the son of the owner showed up to fly his glider. The AMA club field you might be talking about [off SR 530] is going bye-bye too...? I planned on joining there.

MJD, I seem to recall trying a High Start type launcher for a delta and was disappointed. It might of had something to do with cold temps but I didn't realize it.

Viscoelastic slow motion - happens at warmer temps than you might figure! Been bit in the arse twice now.. second time in the 40's. (degrees F I mean!)

I intend to design around that - springs, much elastic and low % elongation.. some such scheme yet TBD.

I have been trying to build a launcher to work reliably, and no joy yet.
Nice to see that the 200+ mph Demon is still around even if it is sans Nelson.

Those pictures belong in the hall of fame! Thanks for sharing before you wiped it off so you could handle it.

Dave

He goes through 2 gallons of Bondo a week. Must be like Pompeii in there.

Hahahahaha! That was the best laugh of the day!

I think the newer body fillers have better built in dust control. Instead of massive clouds of loose particles blowing around, the brand I used most on the last car settled quickly to the floor.
Dave, instead of wiping off the plane, I figured it would be self cleaning after a few flights..!
If I let enough dust build, in a few years it can be peeled off the plane and used as molds.
The inside of this shop is so toxic that even the rats wear dust masks.