scratch built gondola build log for hobby king para wing

[wbuttry]

Hello everybody i'm in the process of building a gondola for a powered parachute .I am not much of a scratch builder so all the help i can get would and will be very much appreciated so to start off i guess i need to list the parts that i have so far. It is gonna be a fairly simple build so here i go ...

1. 3/4 by 3/4 hardwood square dowels for main frame not sure of length i'm gonna build yet .

2.landing gear i'll use it off of a 25 size gasser i got with 2 in tires

3. lite ply plywood scrap pieces

4.sewing thread and gorilla glue i dont use epoxy or ca

5.plastic hoops for knitting i got some 10 incers if need bee can cut and extend we will see will be used for prop guard to keep out of lines out of propeller..

6. using a motor that might be way overkill but i dont half to use full throttle . The motor has 5 1/2 pounds thrust with a 13.6/5 prop and using a 70 amp esc the wing calls for a 3530 motor so if all else fails i can always order a different motor

so far that is what i got i got some nose gear somewhere i'll try to find them and i also got plenty of full size standerd servos to use havent decide on weight shift to turn or use the brakes that will come with time..

[wbuttry]

here i started gluing the frame together there is 2 pieces of plywood sandwhiching the to mounts for the landing gear but only one is glued the other is to help keep every thing in line

[wbuttry]

love this project so far may grow to hate it

[wbuttry]

few pics of the stuff i'm using

[wbuttry]

making more progress. After gear is dried real good then come the verticel pole that has motor bolted to it....

[Birdmanpete]

It is taking shape. Good on you. Interested in that motor. I have one very similar. Does yours have a makers name on it. BMP

[wbuttry]

nope all i know it is from china like everything else is now days but i'm letting all the glue dry over nite

[Fishbonez]

IM sighned up. Looks to be an interesting build. As far as the Spektrum Tx would this be considered an airplane? I assume yes but was curiouse non the less

[wbuttry]

yes it would be considered a airplan i'm gonna use the elevon mix on my spectrum specially if i do the brake for turning left for lrft right for right and down elevater for flare.

[wbuttry]

More photos. Now put on my first upright drilled pilot hole put glue in the hole and dilled a long wood screw to hold it all together then added side braces glued them in. And after i get the main frame done i will sand it down and get all the inperfections excess glue and fill in dips with filler putty. And then get some epoxy and mix up a good size batch mix with alcahol and paint it with the mixture to seal wood and make stronger joints at the end. But i still got a long way to go for that step .It is not perfect like i mentioned at begining of build log im not a scratch builder none what so ever but doing the best i can though and it will stay together after it is done being built i hope...

[wbuttry]

did some reworking on the frame wasnt wanting to hold together so i'll post new pics and everything else i got done so far sanding filling painting hiding glue radio install and servos cage dang i got still another weeks worth of work at least

[Birdmanpete]

Looks pretty convincing to me. The weather is still not quite right for my tests but the leading edge is now lowered by 55mm and it sems like it neds to go lower. I think that adjusting the middle risers is more of a fine tuning thing to keep the underside of the airfoil as close to its manufactured shape as possible. (and minimise drag) BMP

[wbuttry]

Hopefully i can get mine in this or next week so we can start compareing notes. I read the forum part on this wing an it says to hang up side down by the riser strap and move the leading edge riser down one inch and then adjust the other risers to take any play in the strings out. And that is where you start at on this 84 inch wing i'll try that when i get it and see if i can get it to kite like it is suppose to. Then adjust as needed . Is the leading edge suppose to be level or down a little compared to the trailing edge?

[Birdmanpete]

As in any airfoil the centre of the leading edge is about two degres higher than the centre of the trailing edge (and here comes the tricky bit) IN THE FLYING ATTITUDE. With a Paraglider it is almost impossible to establish the flying attitude.

However in my tests I had a little insight today. As the wind gets stronger the wing is less likely to fly over the top of you. That's because your weight acting as a tether is way too heavy and because it cannot lift that weight the weight never "centres" under the wing as it must in forward flight. With my leading edge held down by 55mm I have probably got close to the point where, with a weight in a harness I could let it go and not have it go backward. Taking the slack out of ther middle lines is the obvious first step. Under load things may be slightly different but it will also be very hard to see. I saw an indoors upside down test where someone was using weights at the attachment points. Might be worth trying.

I had another knot let go today. Every knot needs glueing. My next test is with a weight and today's the day.
BMP.

[Birdmanpete]

The picture shows my launch handle; now with 1 pound of old batteries taped on. I raise the wing and when it is almost over head, let it go. At this weight (1 pound) and with less than 10 knot winds it descends, moving forward and shows a glide ratio of less than 1 to 1.
I am happy with the forward movement but the sink rate is too high.

My thinking is that 55mm low on the leading edge is too much and the next test will be at 45mm. Most real Paragliders flown like this with no brake control and no lift source would probably have a glide ratio of less than 5 to 1. I am not sure what to expect of this one. 2 to 1 would be encouraging. At this stage I think more weight would do no good

I have had another line let go but this one was different. This was a failed tab at the wing undersurface. The stitching may have only "pinched" it in place. So now we know the tabs need to be glued into the wing.
BMP

[wbuttry]

sounds like you are getting that wing under control did you say u ordered the 2.15 meter wing also i'm waiting on mine to come in so i can get a good look at it and see what i need to do with mine maybe with luck i will get mine in the next day or to i might just half to build a different gondola for it's first trials and then finish this one after i get this wing flying ...

[wbuttry]

hey bird man i got to looking at that pic on hobby king of the bridal location it looks like it is in full length actuall size pic and actual size bridal setup here is the link cause the pic is long and wide leeds me to believe that putting bridal up aginst that pic and then putting the steel rings even with the ones in the pic and it would be a starting point anyway http://www.hobbyking.com/hobbyking/s...dproduct=14284

[Birdmanpete]

That is one very good observation

[wbuttry]

thanks i appreciate that put it in a pdf file that way you can expand and retract it to get your pefrfect size then match up

[wbuttry]

Finally got a day off from work now i work on my gondola for the para glider. I'm still waiting on the wing. Man thats why i hate ordering from china take foreever but that ok. Test ran motor and everything runs good maybe wing will come this week...

[Birdmanpete]

I have no doubts about the thrust. It really has to go up. Have you given any thoughts to how you will inflate and launch it. I think you might be able to force the wing up with the throttle while the gondola is tethered. On a flat field that could be really neat. BMP.
PS I'm off doing it full size for a fortnight.

[wbuttry]

i'm sure it looks different than you thought it would but like i said i'm not good at scratch building and i'm cheap to and i still have alot of work ahead of me gotta do servos and battery location and place for the bridal location I think the cart would possibly pull it up with me holding the top of the wing then giving it full throttle i think it will rise to the occation and it might even fly i wont be using full throttle all the time just to launch and maybe not even then half to wait and see

[wbuttry]

After waiting a while finally got in my para foil and god it was a mess ropes twisted tied to each other any way very tangled. Dont got them all done yet but got it good enough to seperate the to side. Had to cut the ropes of one of the bridals and retie them. And i see i'm gonna half to do the other side to here are some pics of the wing.

[wbuttry]

here is a link to a utube video on how to adjust angle of attack on this wing from hobby king

HK 2.15 AOA Adjustment for Motored and glider paraglider

[wbuttry]

here is a vid i did today of how far i got and telling a little bit about this project

PICT0001