LEG BD-5 (Newbie Build) - RC Groups
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Nov 06, 2017, 03:16 PM
NeverDun
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Build Log

LEG BD-5 (Newbie Build)


Hi Guys,
I was gifted a LEG BD-5 for my birthday last year, and finally got a chance (and poor enough weather) to make some progress on this thing. It's my first actual plane build, up until this point it's been repairing DLGs, and super simple Dreamflight builds and repairs. So I will walk through what I've done so far, and I'll keep updating as I go. I have been watching the Videos on YouTube (an amazing amount of info on there, thanks Jack!) and supplementing that info with the instructions that SlopeMaster sent me (thanks for those too!). I was a bit hesitant at first, but as I go along I'm getting more confidence and realizing this stuff is pretty easy compared to fixing a DLG boom or wing which was a steep learning curve.
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Nov 06, 2017, 03:18 PM
NeverDun
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aileron actuator sub assemblies:
Nov 06, 2017, 03:19 PM
NeverDun
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wing spar epoxied, and glued into wing half. Reinforcement tube protrusion is within fuselage.
Last edited by NeverDun; Nov 06, 2017 at 06:49 PM.
Nov 06, 2017, 03:21 PM
NeverDun
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Trailing edges CA'd to sub trailing edges:
Nov 06, 2017, 03:25 PM
NeverDun
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Gap at wing root before sanding, after sanding:
Nov 06, 2017, 03:45 PM
NeverDun
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Wing root hot glued while sitting in wing beds. Bought an adjustable temp glue gun for this build, and this was my first time using it. This was a bit nerve racking, and honestly a bit difficult to do quickly enough before the hot glue set. Left with very slight protrusion of wing spar above top of wing. I would probably use goop next time for this job.
Nov 06, 2017, 03:52 PM
NeverDun
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Marked and cut the trailing/subtrailing edges with the razor knife. Cut the angle first with no dihedral, and sanded in the dihedral to match. Then applied Super77 (enough to bubble) to the trailing edges, and waited about 20 minutes. Then I carefully attached them. I added gap filling CA to the wood joint after everything set up. Initially I was a little concerned about the strength of the spray glue. It stayed kind of squirmy until about a day or two later, and then really firmed up. Maybe it's just old.
Last edited by NeverDun; Nov 06, 2017 at 06:51 PM.
Nov 06, 2017, 03:59 PM
NeverDun
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Time to trim the aileron actuators to match the angle and dihedral of the wing. Started by cutting the angle, then sanded the dihedral. Then CA'd the two to the sub trailing edges, and followed up by CAing the seam as well. as you can see, I was a little off on the sub trailing edges, and then I compensated by shifting the actuator assemblies over, but over compensated a little with that as well. I was also slightly off on the bottom of the right side. ARGH. Oh, well. Sand to fit!
Last edited by NeverDun; Nov 06, 2017 at 06:52 PM.
Nov 06, 2017, 04:04 PM
NeverDun
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The ailerons came pre-bveled and shaped on this kit. which was nice. Imarked the location for the actuator rods on each of the ailerons. Measured the wire diameter, and selected a slightly larger drill bit. Marked the depth on the drill bit, and drilled the hole farmer style (no fixture) in the drillpress.
Last edited by NeverDun; Nov 06, 2017 at 06:53 PM.
Nov 06, 2017, 04:40 PM
NeverDun
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Didn't want to spend 60 bucks on a Great planes hinge tool, but found a link through RC groups to a thing called an "Aerobroach". It showed up in the mail with no handle, but an advertisement for a handle. Hrm. That's not very helpful. Good thing I have some tiny vice grips and some jewer's wire! we'll make this work. This too was worth the money. you just kind of line it up, and stab around at a variety of angles along that plane to create a slot. It is harder to use against the hardwood backers on the subtrailing edges, but super easy to use on the ailerons (just balsa). I marked the subtrailing edges on each side, and ran a line across the length of each. I divided up the supplied CA hinges into groups to figure out how many to put on each aileron and have enough left for the elevator. Then I eyeballed even spacing, and marked both sides with the hinges sitting on top. I followed by cutting the two end slots first, test fitting everything, and then adding the center hinges after it's all lined up.

I should have shaped the sub trailing edges before this process, because they weren't perfectly aligned with the bottom of the wing. I then referenced the mounting line for the ailerons off of that bottom edge, so then the ailerons weren't perfect either. Live and learn...I will sand the bottom of the ailerons and the sub trailing edge flush with the bottom of the wing, and the ailerons are going to be a little thinner than expected.
Nov 06, 2017, 04:54 PM
NeverDun
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After dropping the wicking CA into the hinge slots, the hinges became much stiffer. I realized after watching the video I may have gone overboard with the number of hinges I used, because they are too stiff now. Stiff enough that the aileron is twisting along it's length when actuating it from the control rods. Should I just stick a blade in there and trim them down so they are narrower?
Nov 06, 2017, 05:29 PM
NeverDun
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Time to trim the ends of the wings down so the ailerons sit flush with the tips. marked the tips equidistant from the ends, and mitered them off, leaving as much of the wing as I could. Then I sanded them down, and shaped the tips. I went a little overboard with the leading tip radius. The BD 5 isn't as large a radius as what I made, but hopefully it flies fast enough no one will notice.

I would like a removable wing in case things get interesting, so I added an 1/8 inch plywood plate at the front of the wing. Hot glued in place. I will probably pot a hard point here from the top with epoxy later so it doesn't work loose, since the foam is a little squishy..
Nov 06, 2017, 05:39 PM
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I decided to reinforce the ailerons with carbon tow for three reasons:
I'm paranoid I'm going to destroy these nice balsa ailerons on something hard
They flex a little more than I like now that I sanded them flush with the wing profile
By the time I got everything sanded flush (back to my mistake with the Sub-trailing edges not being flush with the bottom), the actuator rods were starting to show through the top of the ailerons. This looked like a major problem to me. So I mixed up some good laminating epoxy, pulled some carbon tow apart to get it as flat and thin as I possibly could, and layed it on the ailerons and trailing edge of the wing. One trick I figured out with DLG repairs is after you wet it out, and blot out the excess resin with toilet paper, you carefully apply clear packing tape over the top of the tow. this only works well for repairs without compound curves, because the tape doesn't stretch. Then you can not only handle the part while the epoxy is setting up, but you can also massage excess resin out of the ends of the matrix with a scraper, and push the tow around a little if it didn't go down quite right.
Nov 06, 2017, 05:45 PM
NeverDun
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I may apply kevlar to the bottom of the ailerons as well using the same technique when I do the wing root,though this may be overkill.
Nov 06, 2017, 06:05 PM
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While the wing set up, I decided to assemble the Horizontal stabilizer. This was done pretty much exactly the same as the ailerons, except they need to be beveled to 30 degrees top and bottom first. I lined up the elevators and cut the hinge slots first (only 4 total this time), but I didn't glue them in place. Then I lined up the elevator actuator with the centerline of the Horizontal stabilizer, and marked where the holes needed to go, as well as the flat to clear the wire before it enters the elevators. I'm not accurate enough drilling holes by eye, so I drilled these holes a little oversize (the same size drill as the ailerons works here perfectly, because the wire is smaller on the elevator actuator).
Once the holes were drilled I could dry fit everything, and cut a clearance notch for the actuator movement in the trailing edge.
after dry fitment, I mixed up some 5 minute epoxy, and epoxied the sanded ends of the actuators into the elevators. I set them on a flat surface, and allowed the larger holes to accommodate any alignment problems from my drilling. I made sure the gap spacing was even all the way across the trailing edge, and put a piece of parchment paper between the actuator and the trailing edge to prevent the epoxy from gluing everything into one solid piece.
Once that was done, I double checked the hinge gap, and glued the CA hinges in place.
Last edited by NeverDun; Nov 06, 2017 at 06:24 PM.


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