Tony Hallo

Time to fit the wings to the fuselage. The fuselage is compound shape in that in bends in all directions. The root rib is 1" thick to allow fitting. I measured and found the largest gap at 1" and the smallest at 1/8". I cut a piece of scrap liteply at 1" to mark the outline on the wings. This was done with the wing set at 0 degrees incidence.

Tony Hallo

This is what the lines looked like, bottom is on the left side, top on the right.

Tony Hallo

I cut through the sheeting with anExacto blade then using a flush cut saw cut through the foam using the knife cut as a guide. It's easy to get off track so I work slowly as the knife is tilted back and forth following the top cut then the bottom.

Tony Hallo

Here the cutting is progressing.
The finished cut. You can see the angled lines in the foam from holding the saw on an angle while cutting.

Tony Hallo

After several off and on and sand some more drills I was reasonably close. The root will be fitted with a 1/8" lite ply plate. The plate is cut oversized so that it can be clamped to the fuselage and follow the contour. The hole for the wing tube is drilled oversize to allow the wing tube socket to engage into the plate.

Tony Hallo

I used poor man's release agent on the wing tube in the area of the glue joint just to be sure I can takeit apart. The plate will be glued on with poly glue, who knows where the glue will foam to?

Tony Hallo

This is what it looked like this morning. I used masking tape near the edge of the wing to keep the poly glue off.
I bought one of those multi tool some time ago and finally got to put it to use. With the scraper attachment I cut under the foamed glue down to the plate, once this was scored, I used the flush cut saw to cut away the excess.
Once the second wing catches up, I will fit the alignment pins, then cut and finish the ailerons.

prgonzalez

[sm=thumbup.gif]

Excellent !

Tony Hallo

I level the fuselage off of the horizontal stablizer mount, thewing is installed and the incidence is set. I use both the gage at outer portion (Don't have a long bar for the electronic gage) of the wing platformand measure from work bench to the centerline closer to the wing root..
I cut vee shaped pice of scrap liteply to hold the wing in postion, this is easily adjusted to get everything right where it should be. The measurements at the fuselage were equal so I was good to go.

Tony Hallo

The fuselage was leveled and the alignment dowel holes were pre-drilled in the drill press before hand. The dowel holes and the wing tube must be pararell so that the wing slides on. I drilled through both holes into the wing using a 12" long drill bit.
The 1/4" aluminum dowelsare glued withpoly glue.

Tony Hallo

Cut lines are established for the ailerons. I cut through the sheeting with an Exacto knife,both the top and botom are cut. Then saw through the cut lines with a flushcut saw. For those of you that never tried aflush cut saw, you better getone. I found this knife at the HarborFreight store, thoughtI'd give it a try. Rarely do I usetheZona style saws now.

Tony Hallo

I'm installing doubled beveled edges at the hinge line withSigpin style hinges,both edges are 3/8" thick and tapered to 10 degrees on each side providing a total of 20 degrees movement. 3d throws are not in the cards. I wanted to try the multi tool for hinging since that wasthe main reason for buying the tool. The balsa edges are 1 1/2" high so I used a piece of 3/4" thick sheeting as a guide for themulti toolblade. Hinging is one operation that I dislike, the multi tool worked well, I will use this method again unless something better comes along, the blade thickness is perfect for giant scale hinges.
Once the hinge slots were cut, I beveled both edges. Again I tried a different approach. In the past I craved the edges to shape, then finish sanded. Here I screwed a 4' straight edge down to the bench top so that the balsa edge could be clamp down leaving a 3/4" space between the edge and the straight edge. The power plane was guided along the straight edge, the first few cuts don't remove much material, once the corner gets knocked off, the dust really starts to fly.
The planed surface gets sanded in similar fashion with the sanding bar being guided by the straight edge.

Tony Hallo

I mark the surface with a pencil on it's sidebefore planning begins. This makes it very easy to seejust how far away the plane isfrom the centerline. Asthe materialisremoved, thepencil mark disappears. Once there's 1/16" of the pencil marking left signalsthe time to switch to sanding.

Tony Hallo

The trailing edge is glued on. I cut vee shaped blocks for clampling. The centerline is set at ends and checked with along the length with a straight edge. Once dry the top and bottom surfaces are sanded flush to the wing.

Tony Hallo

The hinges are inset into the edge to allow a gap the thickness of the hinge wire. I heat Vasoline to make it liquid and paint the knuckle to prevent glue from sticking the whole ness together, the hinges are staged at the bottom of the photo.
I had hoped to use Mecury 30 minute epoxy for the job. I've done this many times so I proceed to mix a batch, load it into the Monoinject, fill the slots and slide everything together. The epoxy was leftover from a build I did this past August, so it's3 months old, I had to heat the resin in the microwave to dissolve the chunks, kinda reminded me of 5 minute epoxy that I rarely use. Everthing was going as planned, filled the slots, when back over to top them off again, insert hinges into first wing, put the aileron on but it will not go on, epoxy set up, check second wing, same state. Think to myself, smells like 5 minute epoxy, could it be? Mix up batch on the bench, it is 5 minute epoxy. Luckly I was able to dig out the cured epoxy with damaging anything, I then proceeded to glue the hinges with poly glue.
The lesson learned here if it smells like 5 stuff, it probally is, do a test to confirm. If the folks form Mercury want to check it out, I'd be happy to set it back.

Update
I when back and read the box, my mistake, It states 30 minute bond, 1 hour cure. And I always thought time time stated was working time! Read carefully. Sorry if I mislead anyone.

Tony Hallo

I found some old stock Rocket City Hardware at the LHS during a recent visit, this is what I'm planning to use for theailerons. This is nice stuff and I'm sorry that they are no longer around. This hobby sure has changed in recent years. The servo pocket is cut with the Dremel tool and the router attachment, I made the jig several years ago.
The trusty flush cut saw is used for it's intented purpose, cutting off dowels flush.
A 5/8" brass tube is sharpen and used for drilling the ribs to accept the wing tube.

gene6029

Comming along nice! Still following along...Gene

Tony Hallo

Good, I still got the plans for the Urley Laser, might just build another some day. I flew mine with a 50 CC Homelite conversion at first, then later upgraded to a G62. I had a dead stick while attempting to hoverand theairframe sustained minor damage. I gave it to a club member and heflew it for 2 more years before it met it's demise. All told the airframe lasted 14 years.I think I paid $190 for the Bud Lite decal set, that was big bucks back in the day.

Todayan eighty or 100 would be considered the norm for a 33% bird.

Tony Hallo

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Tony Hallo

The wings are basically done and ready for final sanding. Time to wrap up some little details here and there. I made the rudder post fairing from lite weight balsa plank, it is hollowed to loose some weight. I didn't go crazy, it might be 1/4 to 1/2" thick.
The tail wheel is a low tech Ohio Superstar Haigh unit, 12-22 pound size. I inset the wire into the tail plate and used flat straps to retain in position.

Tony Hallo

I like the gear hidden where it is bolted to the fuselage. The ARF's today do a great job covering the fuselage and providing fairings much the full scale. The covers are madefrom1/4" balsa. Two 4-40 screws hold eachcover in place, the landing gear is drilled and tapped for the screws.The gear fairings are fiberglass layups, these were copied from a vacuum formed fairing I picked up in Toledo many years ago from Bob Godfrey,
Directly behind the gear are the louvers where the engine cooling air exits

Tony Hallo

Here you can see the cooling airflow path. Air will enter through the two front inlets behind the propeller and be routed through baffles over the cylinder heads. Travel through the firewall below the engine box and exhaust through the the louvers. I do not plan to provide any other openings in the cowl.

sensei

What a really great job you are doing!

Bob

Tony Hallo

I took some time off this build to change engine in my Extra 200, I swapped out the ZDZ 80 Super with D&B 5.1, I used the same can that was running on the ZDZ, we'll see this works out this spring when the weather improves. Time to get back to work.

Tony Hallo

On another site I found a tip from a J Miracle thattreating the airframe withhair spray prior to final sand will improve the covering job, I decided to give it try. The hair spray contains polyvinylpyrrolidone, which is also used to glue the layers of wood in plywood together, the glue causes the fibers to stand up and makes for better sanding results. I found this most noticable on the wing tip blocks where the end grain was exposed. I sprayed the wings after the 220 grit sand was complete then finished off with 320. To clean the surface I first vacuum, then blow off the parts compressed air and just prior to putting down a piece of covering I wipe the surface with Prepsol cleaner, just dampen a paper towel, not wet.