Thread Tools
Dec 08, 2016, 11:25 PM
Registered User
Gregco10's Avatar
Name: 20161207_192753.jpg
Views: 48
Size: 483.1 KB
Description:

Name: 20161207_192729.jpg
Views: 48
Size: 454.2 KB
Description:

Name: 20161207_181902.jpg
Views: 43
Size: 391.3 KB
Description:

I got a couple of these to build with a buddy who never built a kit before, should be a trip. In the mean time I replicated the kit in 1/4 pink insulation to try a really light setup. This one I used a 2mm rod and strips of carbon embedded in the foam. I was wondering if anyone has tried to put the main spar in the wing as opposed to under it as the kit suggests, and how it worked out. I'm not a big fan of the draggy thing hanging out on the bottom.
Sign up now
to remove ads between posts
Dec 26, 2016, 10:11 PM
Registered User
Gregco10's Avatar
Started assembly on the actual kit. Decided against using the tube spar and went with a 0.5x4mm flat spar instead. I ran a line where the tube would be and cut all the way through. Then foam cured it in. Will let you know how it goes.

Name: 20161226_220931.jpg
Views: 56
Size: 372.6 KB
Description:
Feb 04, 2017, 04:14 PM
Registered User
Gregco10's Avatar
I'm posting this here even though it is not exactly the original kit but the info might be useful.

I have the Hobbyking kit assembled and ready to go, the setup is 1300mah 3s, Sunnysky 2208 2000kv, 20a esc. Only thing is that I am building with a friend who hasn't finished his kit yet. When he is done we will test them together. In the mean time before I assembled the original I used the pieces as templates for this plane shown in the video. This is cut from 1/4 insulation foam and is a very close copy of the original. This one might be slightly stiffer. I built this to try out a very light setup that I had no intention of doing with the original but looking back may have been a good idea. Its a nice light setup suitable to a small field that can handle some wind.

-Setup is: 850mah 3s, 1700kv 2730 Blue wonder type motor, APE e 6x4 prop, Fms 20a esc, hxt 900 servos, Frsky radio.
-The cg was just in front of the wing break then brought it just behind for better response. I am going to try bring it back in small increments. This would be a good starting point for the original kit since it is not marked.
-For its size the control surfaces are small in area, so in a small field you will need some throw during testing. This should be less of an issue when the cg is correct.
-286 grams

Sorry for the yabbering, sometimes I talk, sometimes not. Beginning of flight with better cg @ 2:55

Primejet8 Prime Jet hobbyking clone Greg006 (7 min 43 sec)
Last edited by Gregco10; Feb 04, 2017 at 04:28 PM.
May 08, 2017, 09:56 PM
Registered User
SilbernerSurfer's Avatar
Whats the weight of the plane without electronics?
May 09, 2017, 10:15 PM
Registered User
Gregco10's Avatar
I just so happened to have my built up Hobby King frame hanging on the wall less all the electrics, 112g. I did not use hot glue and I used a different lighter spar, so mine might be a bit on the light side.
May 09, 2017, 11:03 PM
Registered User
Gregco10's Avatar
I almost forgot to post this. The setup here is a 2208 2000kv Sunnysky, apc e 6x4, 1300mah 3s.

It flew ok. Only problem was the flutter or twist. I was able to see the right wing twisting up at high speed and causing the plane to lean over to the left. The ailerons weren't able to correct it. Then it would snap right if you backed off the power, expected but spooky. When flying at reasonable speeds the plane behaved nicely.

Now to be fair I did not build it to HK spec. The instructions called for gluing the carbon dowel spar under the wing. I was not a big fan of this and decided to put a carbon flat vertically set in the wing for better aerodynamics as a substitute. Perhaps a mistake but I really didn't like where it was supposed to be. I think some kind of triangulation of carbon set in the wing might have worked better. My friend decided to cut the wing and set the stock carbon rod in the wing, he had slightly better results with the same power combo but still had some twist. We also decided to change it up a bit since we saw some videos with what seemed to be the stock setup that had flutter.

Its a nice plane it is just more suited to a lighter setup IMO. The foam is very tough and it builds to a durable airframe. As of now I have taken the components out of mine for other projects. I like the clones setup better and that is still flying. I will probably set up the stocker again some other time and again will go light.

Hobby King Prime Jet Glue and Go series Hobbyking Greg006 (7 min 19 sec)
Jun 01, 2017, 12:01 AM
Registered User
Well I have put my Prime Jet together. The biggest problem is finding a glue that works OK. All the usual glues had only partial success. Cyano, white glue, gorilla, hot glue (when used for carbon spare it sets before laying glue right along wing)even contact glue I had. The instructions say what glue to use but that is useless information if HK never have it in stock! The control surfaces started to come apart before being finished. Used Blenderm. Motor mount fell out after 2nd flight.
Now fly was a different story. Race Star 2208 2400 kva motor, 1300 3 cell and a 40 amp esc (used a 25 amp for 1st flight, got a bit warm). Model flew straight from launch with little or no trim required. Flew great. But, when power backed off - battery died - its glide made a house brick look like a thermal soarer. After 2nd flight landed that's when the motor mount fell out and some of the other glue joints started to fail.
If the construction methods matched the flying experience this would be a great, cheap model.
Why for a couple of extra dollars the correct glue could not be supplied and save a lot of hassles for people who do not have ready access to a large range of glues.
I will persevere with different glues till I get it right.
Jun 01, 2017, 01:28 AM
Registered User
Gregco10's Avatar
I think they recommend hot glue which usually will stick to anything, but I didnt want to go that route. Welders adhesive works great and did not melt the foam. If your gonna try it do a test first just in case the foam is different for some reason.
Jul 04, 2017, 10:51 AM
Registered User
Gregco10's Avatar
I took it apart and set it up again, it is very nice set up light. Unfortunately that lamp post, I think it has legs or something because it was NOT there when I first started flying 😄

Hobby King Primejet light setup re maiden nice flight Greg006 (7 min 22 sec)


Who put that pole there? Hobby King Primejet tuning and crash Greg006 (6 min 52 sec)
Aug 15, 2017, 03:26 PM
Aussie freezing in Holland

rx setup


is this flown with just ailerons? a Y cable and its ready to go?
elevator or rudder mixes?
how do you get it to go up and down and turn? I am used to a 6 channel setup not 3
Aug 15, 2017, 03:31 PM
Aussie freezing in Holland
Quote:
Originally Posted by Gregco10
I took it apart and set it up again, it is very nice set up light. Unfortunately that lamp post, I think it has legs or something because it was NOT there when I first started flying ��

https://youtu.be/Ycn9wgdIEcs

https://youtu.be/pYHZAbVqfjA
I have that prob with tree's..

Got it,,just learnt a new trick on my Taranis. Elevon mixing..
Last edited by Troppo1; Aug 15, 2017 at 11:24 PM.
Aug 16, 2017, 12:22 AM
Registered User
Gregco10's Avatar
You got it elevons. You might find it needs a good amount of up elevator throw, it rolls easy enough but pitch needs some help. Otherwise a pretty good flyer.
Aug 16, 2017, 07:32 AM
Aussie freezing in Holland
Quote:
Originally Posted by Gregco10
You got it elevons. You might find it needs a good amount of up elevator throw, it rolls easy enough but pitch needs some help. Otherwise a pretty good flyer.
thx. i'll go up to 75% elevator en leave ailerons at 50 and see how the maiden goes.
how tolerant is the cg? I got 1300 and 2200 mah to try and where is exactly the CG?
Aug 16, 2017, 09:05 PM
Registered User
Gregco10's Avatar
That sounds about right to start on the throws I guess , its hard to tell without knowing the actual deflection, but less on the ailerons and more on the elevator sounds right. Yeah good luck with the 2200 unless you are willing to throw overhand, have a good follow through to escape the prop and get back on the stick quickly to get it flying. The 1300 3s works great, it is lightly loaded and requires just a good shove to get moving for flight. It seems the cg has a pretty wide range, too far up though and it becomes a slug and will not land nose up glided in, hence the more elevator throw. (it will also be very sluggish on the pitch)Get it right and it will land flat, be nice and stable in flight, and be responsive on pitch. I don't think I have had it too far back where it was unflyable but I'm sure there is a point.
Aug 16, 2017, 09:12 PM
Registered User
Gregco10's Avatar
Cg is try 5mm behind the wing break to start, then work from there where its best for you.


Quick Reply
Message:

Thread Tools