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        Discussion BUSA N17 1/6 Build

#1 Thermalin Jan 22, 2012 07:24 PM

BUSA N17 1/6 Build
 
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Thought I would post some pics of a BUSA Nieuport 17 1/6 build I have going. I placed and taped some things together to get a look at it. My first bipe and so far so good. It's been pretty straight forward so far. Two unusual areas where the sheeting of the front fuse which was done in two pieces on one side and a single piece on the other as they are not symmetrical. Other area was the lower wing dowels. Wasn't real happy with the orginal design as it looked quite weak so I added some more strength to it.

I'm making a hatch on the bottom area forward of the bottom wing for access - pic 1. This was to be permanently sealed up and this closes up the only access is via the narrow wing opening in the bottom or through the cockpit.

#2 wizard of odd Jan 22, 2012 07:58 PM

That's a very neatly built model, well done so far!

From the hatch installation I deduct this will be an electric powered model?

Please post more pictures as you progress with the build.

Odd

#3 Thermalin Jan 22, 2012 08:56 PM

Not electric. I'm planning on using a Magnum .52 four stroke I'm breaking in. I like having access to things. I'm going to cover the front-most opening permanently to strengthen up some since it won't all be fixed. Current plan is to mount t inhe servos inverted down low in that front opening. They would connect to tiller located above the bottom wingarms for rudder and elevator for pull pull. All pie in the sky at this point.

#4 Thermalin Jan 24, 2012 03:36 PM

Drilled and tapped the the wing bolts in the lower wing. When done.. the left side tip was 1/8" off from the right in hieght from a level serface so I'm not going worry about that since it could be from any number of things. What does concern me a bit is the incidence seems is a little bit off. They say to stand on it's (current) flat nose and use a square. Bottom of wing should be flush to the square (wing bottom 90 degrees to the bench). From bottom spar to TE of wing, it tails away from the square slightly leaving a very small space. So assuming all is square this would be some very slight negative incidence. I don't want to try fly that way so I'll have to fix that :( .

#5 Thermalin Jan 25, 2012 02:15 PM

Double checked the incidence one more time and noticed the area at wing center where I initially measured was a little off. This morning I ran the straightedge along the entire wing and it was fine on both sides. Since the center area is sheeted and sanded, Im assuming that my issue is in that one area, so it's off to soldering the clips to the rear piano wire cabanes this evening.

#6 Thermalin Jan 25, 2012 09:25 PM

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Ran into an issue with top wing intall / alignment and I should have seen it coming. It's my first bipe and thought I'd follow instructions as written. Instructions said to locate the blind nuts in the top wing (rear) per the plans as well as sheet over the center section. I installed the blind nuts but did not sheet as I like to do that last once all is in place. I soldered the clips to the rear metal cabanes per instructions. Once the rear supports were in place, the soldered clips didnt line up with the blindnuts. I'm not the best builder but I'm good with the details and they didnt line up at all. Also noticed the holes in the clips soldered to the cabane wires weren't large enough to accept the socket head screws. Going to pull out the ply plate holding the blindnuts in the wing and re-install a new one, drilling holes to match the clip hole locations and then install the blindnuts. This is how it should have been done intially in my opinion rather than pre-locating everyhing and hoping for the best.

#7 Thermalin Jan 27, 2012 11:20 PM

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I cut out the original installation of the upper wing ply plate holding the blind nuts. This per the pic was a sheet of ply with a doubler for each blind nut. expoxied to rib cutouts and the rear spar.

I replaced with a single ply sheet of correct thickness all the way across which required a bit more of the three ribs to be removed to recess the new thickness.. I added some tri-stock bracing at the outer most ribs. Then added 1/16" doublers on the outermost ribs from the main spar back to the rear with tabs to fit in there. This gave the ribs quite a bit more strength. The additional weight I think was minimal and I usually overbuild things a bit.

So now I'll be able to correctly mark the holes for the blind nuts when I go through the process of aligning the upper wing to the front and rear cabanes. The front of the wing still needs ply plates installed that will attach to the front cabanes. I;m hoping to get the upper wing in place in relation to the lower this weekend in order to start making the V struts out in the wings.

#8 houndstooth Jan 28, 2012 09:37 PM

greetings Thermalin,...this is houndstooth,... i just joined,... and saw your build on your N-17 ssssaaaweeeeet!!! that B.USA kit was my first bipe build too!!! And, let me tell ya, it flys like a dream!!! I have a O.S. 40 L.A. on it, 90 degrees with a pitts,.. hands off, half throttle, and she'll fly straight forever!...This will be her 4th summer. Your build looks real good. Do'in some things I wish I'd done... Just in case,.... a 2 OR 3 degree right thrust on rhe engine mount will help TREMENDOUSLY!!! KEEP UP THE GOOD WORK!

#9 EJWash1 Jan 28, 2012 09:42 PM

Always a pleasure to watch your builds!

EJWash

#10 Thermalin Jan 29, 2012 10:50 AM

Houndstooth... I'm glad to hear of the flight performance. I'm quite nervous pof the very short tail moment and all this building needed. I don't mind crashes but I would like to get several flights before a major ding :). I'll start with the 2 or 3 degrees right thrust as the instructions or soft of fuzzy on where to start. No down thrust??

EJ.. thanks!

I test software in real life so i thought I would try a test on these pesky cabanes. Last night I removed the soldered clips and filed / sanded everything down to metal again. Placed them in the slots and with everything level.. a bubble level on the cabanes was not level with 1/4 in and 3/4 out of center. I switched them in the slots and what was the high side was evern more pronounced in the opposite direction with the entire bubble pegged to the side.

Looking at the cabanes stacked, the top of one was off. But what would cause the difference between the two sides. The bottom wire bend is a good 2 inches long and slides into an upside down landing gear block that is glued to a base. Movement is easy yet firm so i dont think that's it. Either way, I'm going to fix the top bend issue on the wire and and use in the side that was minimally off. There's a good 4 or 5 steps to algin the wing before N sturts start so we'll see. Off to the garage

If anyone is into survial type movies... I saw the The Grey last night ...Enjoyed It. My two thumb system is One Up.. One Sideways.

#11 Thermalin Jan 29, 2012 10:26 PM

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Well a new challenge appeared tonight. I resoldered the rear cabanes and they came out real nice. I'm using my propane torch now instead of an Iron which works much better for me. Pics show the 3/8" ply front rib inserts. 3 pieces of1/8" ply laminated. They were put in the front and are used to attach the front of the wing to the front hardwood vertical pieces.

I set the upper wing in place on the rear wires and soldered clips being sure they were vertical per instructions.With the clips centered on the ply plate, the leading edge was the correct distance it was supposed to be back from a vertical line coming up from the firewall. That was a nice surprise. It was then I noticed with the wing the correct distance fore / aft, the ply rib inserts were not centered on the vertical supports. It may not show in the pics but the hole in the tabs is to close to the side of the hardwood for me to feel ok with.

Not sure what I'm going to do about this new snafu. I'm not going to remove them as they were installed with expoxy and due to the stress in that area, I made sure they weren't coming out easily. Would be nice to just a cut a new set with a little different profile below the wing but that option is out. Not sure how this could have gotten by BUSA?

#12 Thermalin Jan 29, 2012 11:14 PM

I;m thinking I could add an additional piece with a tongue into the orginal vertical support, extending it so the tab hole would be centered on the widened support.. Seems far fetched but would work.

#13 Thermalin Jan 30, 2012 07:48 PM

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I had an idea on the way home today and will be adding the additional width to the wing mounted tab and not the vertical hardwood cabane. The tab is thicker by 30% and it will be easierr to accept the additional wood.

I made up the shape using three ply pieces with the middle piece extending out for the tongue. I cut a channel in the current wing mounted tab and will slip it in with epoxy. It's glued up now and I'll fill it in and clean it up tomorow

#14 Thermalin Feb 01, 2012 02:31 PM

Filled in and cleaned up the tabs but having issue with setting the wing. There is a gap under the right rear cabane mount of about 3/16 inch yet wing looks level. Because the wing mount tabs are long (vertical) and rest snuggly against the forward cabanes, there may be an issue there inducing some non level twist.I'll see if thats it and if I'm able to tweak the tabs with some sanding to get the wing to lay flat. Looks to be angled slightly from front left tip to right rear tip. It's warp free so it its just not sitting square at the 4 attach points. The wing sits on top of the two rear points and slides onto (between a rib and mounting tab) the foreward cabanes. I would really like to move past this so I can get to more fun stuff. Taking my time though for if this is not right, it will be an ugly maiden!

#15 Thermalin Feb 02, 2012 10:51 PM

I have got the measurements figured for postioning of the top wing and have it mounted on the rear cabanes for starters. The measurements that all needed to be in sync were:
1) Leading edge back from firewall
2) 0 Incidence to match bottom wing
3) Equal distance from bottom wing on both sides at some outward point on bottom wing.
4) Wing square to the fuse centerline so niether tip is fore or aft..
This was quite a few things to get in place at once but I'll have the wing mounting complete tomorrow and start on the V struts.


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