Rebsix

My Feedback: (8)

Well, after searching for a build and not finding one, I figured I'd post pics of mine.

It's a kit a guy in the club bought and traded me a new Saito 91 for the labor, not a bad deal.

Rebsix

My Feedback: (8)

I punch out the ribs, line them up on one of the spars. I cut two short pieces of spar and lock them into the ribs to keep them straight. Then I drill a few holes front and back the same size as my arrow shafts (see later post) making sure I keep the ribs lined up.

Then I use the belt sander to true them and make them all the same size.

Rebsix

My Feedback: (8)

On my homemade wing jig I put half the ribs on since it isn't long enough to do a complete wing. As you can see the jig lines the ribs up nicely.

Using the plans, I mark the ribs on each of the four spars so I can line the ribs up on the jig using the marks. I use a square to keep them plumb and measure the first rib off the jig to keep the whole thing square and continue the technique for the rest of them.

When everything is plumb and square I hit all the joints with CA.

Rebsix

My Feedback: (8)

Now I glue the leading, and trailing edge on with thin CA.

This is the beauty of the jig. I can take the wing out and the arrows stay keeping it square.

After it sits for a bit, I unscrew the wing nuts on the jig and hit all the joints again with medium CA to make sure a good joint is achieved. It's pretty fragile at his point but with the arrows still in and a little care it won't move anywhere.

It's locked back in the jig making sure to measure for square and go refill the coffee while the glue dries.

Sheet the topside front and back with slow and install the cap strips, then flip it over to do the same to the other side. I take it off the jig and pull the arrows out (if you didn't drip CA on them) and I sand it smooth.

Repeat all the above steps for the other half and low and behold, I have a wing.

Rebsix

My Feedback: (8)

I sand a bevel on the two center spars so they don't hook and split a rib when inserted.

I run the arrow shafts through both wing halves to keep them lined up while the glue sets. Everything is glued with 30 minute epoxy and clamped to sit overnight.

Rebsix

My Feedback: (8)

Fuselage parts are punched out and joined where needed, ready to go into the fuselage jig.

Once everything is lined up a few drops of CA hold it together. Then I cover all the joints with 30 minute epoxy.

Rebsix

My Feedback: (8)

After it's dry I can take it out and flip it over to sheet the bottom. When I take it out of the jig I only loosen the blocks on one side so I can put it back in the jig without having to line everything up again, I just lock the loose side down and sheet it. Then I flip it back over and add the tri-stock to the inside with medium CA. I let it sit over night and it's solid as a rock for servo rails and push rods.

somegeek

My Feedback: (2)

Damn - this is one clean looking build! Enjoying the pics. Thanks for sharing!

I really dig that fuselage jig.

somegeek

Gray Beard

My Feedback: (-1)

That is really the slickest jig I have seen for building A fuse. I would like to see A build thread on just that. My Hots kit had some warp in the fuse wood and I had A heck of A time keeping it straight. That jig would solve A lot of building problems for A lot of people. Great idea.

beachflier

Looks like the jig at [link=http://webpages.charter.net/rcfu/ConstGuide/FJConstr.html]Fuselage Assembly Jig[/link]

Rebsix

My Feedback: (8)

Yup, that's exactly where I got the info to build both jig's. I built them probably two years ago and couldn't remember where they came from, thanks for linking the sight.

Rebsix

My Feedback: (8)

Here's a trick several of you probably already know, but as I was putting the sheer webs in I dropped something on the wing and created some bad dents. I plugged in the iron and put a few drops of water on the three dents and let the soak in for a few seconds. Then I hit them with the iron and poof, all gone.

I usually go over the whole plane before I cover it and get out all the dents this way.

Rebsix

My Feedback: (8)

Now that everything has had a chance to dry, I pull my arrows out of the wing and glass the center. Then I install the machinery for the strip ailerons. Now I can sand and form the wing to the fuselage making sure it's straight and level.

The plans call for 0-0-0 incidence so I set the wing up according to the firewall which is already installed.

I didn't take pictures of it, probably because of frustration, but the hardest part during this process was keeping the wing bolt holes, the cardboard tubes, aileron horns, and servos all out of each others way. It's been a year since I built this plane and I don't remember the exact procedure but I do remember having to move the servos. The instructions are either incomplete or incorrect during this process, either that or I was up way to late doing it. more to come on this.

Rebsix

My Feedback: (8)

The tail feathers come in two pieces each so they have to be glued together on the edge. I used medium CA and lay them flat on top of waxed paper to keep from gluing them to the table. I sand them flat with a block and if there are any gaps, the dust mixes with the still wet glue creating a seamless joint.

I use medium again to glue the spruce tips on the horizontal stab. Since balsa is softer than spruce, I put the tip on the edge of the table and sand at a slight angle until I can't feel the joint anymore. By the way, I use 80 grit for everything during building, and hit it with 220 to smooth it out.

With the wing mounted and true I use the standard measuring techniques to square everything. The back, outside corner of the wing to the leading outside corner of the stab. Then double check from each side of the firewall to the corresponding leading corner of the stab. Then from the inside corner where the wing meets the fuselage to the outside leading corner of the stab. These 3 measurements usually don't come out exact. One will be off while the other two are on, or any other combination you can think of. I try to split the difference if it's within reason, 1/8 - 1/4 from the best to worst. If it's beyond that then some additional construction has to be done. This one came out well within the 1/8 inch mark and I was happy with that. I contribute that to the two jigs I used.

To make sure the stab isn't canted to the wing I simply use the Billy Lane motorcycle building technique, I eyeball it.

Since there is no slot or tabs to lock the vertical stab in place, I drill holes in it and epoxy two or three toothpicks into it leaving about 1/2 inch sticking out. I use the center line I marked to gauge where the toothpick holes have to go to make the vertical stab true to the center line of the plane. Then I epoxy it together and the toothpicks give some added strength. The holes carry through to the plate that the horizontal stab is glued to which lock it to the plane. I hope I explained all that properly.

Before gluing it to the plane I check the incidence again making sure the tail is zeroed with the wing which is in turn zeroed with the firewall. The meters don't have to read zero, they just have to read the same. I can prop up the front or back with scraps to make them read zero and this will show me the attitude the plane will fly at if I have everything set properly.

I glue it all with 30 minute epoxy.

Rebsix

My Feedback: (8)

This was the hardest part of the build, but it has to be done if the wing is going to be detachable. I used medium CA for all of it.

In the first pic you can see a small block inside the fuselage, it's a jig that comes in the kit. Spot gluing it in with thin CA sets the angle the F3-A former rests at and it's glued in. Then I think four pieces of printer paper are put in between F3-A and F3-B formers and F3-B is glued to the wing. The same process is done for the front with the F2 and F2-A formers using a scrap piece of spruce as a jig and spot gluing it to the wing and the former.

I decided to replace the stock control rods with Dubro's since all they consisted of was some small plastic tubes with some even smaller metal wire. The wire wasn't threaded and it was smaller than 2-56, I didn't have anything to solder onto them for a clevis so the Dubro's saved a headache. I crissed and crossed and routed until I came up with the setup in Pic 2. The inner rods almost fall out if I hold the plane vertical. I also take a #2 lead pencil and rub it up and down the inner rods for lubrication.

Now I Put the spruce stringers in connecting all the bulkheads. The four sheets of paper are still in between the formers so I start from the front and keep sanding the end of the stringer until it fits firmly but doesn't move the former out of place. The I go from the tail to the F3-A and do the same thing. Now the hard part. Getting the center stringer exactly the right length so it doesn't move the formers and tighten them onto the one next to them. If the stringer is too long, when you cover the plane the seam will be wider at the bottom and tight at the top. The paper helps prevent this but it can be over done ruining the seam. Now I break out the two jigs and it's starting to look like a Hots.

beachflier

Rebsix,

Looking good. Thanks for sharing your build with us.

Rebsix

My Feedback: (8)

Thanks Beachflier, I'm glad your enjoying it.

Time to sheet the fuselage.

The 1/16 balsa sheets are joined at the edge. I like to sand them true so there are no gaps and then I run masking tape the full length of the seam. Then turn it over and open the two sheets with the tape acting like a hinge. A fine bead of medium CA down the seam then lay it flat on the table taped side down until it dries. I've also used thin CA and I leave the part flat on the table letting the thin wick it's way down the seam. I added the 1/16 inch balsa scraps for strength, making sure they don't line up on any formers.

Before the sheet is glued on, I ran a 1/4 inch strip of 1/16 balsa the full length of the section being sheeted. 1/8 of it is glued to the fuselage and the other 1/8 is sticking up above it so the sheet has something to adhere to.

I used medium CA and clamped it on until it dried. Where the new sheet meets the fuselage ply, I ran a thin line of medium into the gap and sanded the joint filling the seam with dust. The glue adds more strength and the dust mixes with the wet glue so once again, I have another seamless joint.

In the 3rd pic,.... well, ya just gotta sign your name don't you?

I repeat all the steps for the other side and now there's no mistaking the Hot's shape.

Rebsix

My Feedback: (8)

Pretty much all the same procedures to sheet the rest of the fuselage, I'd guess you'd call this the cockpit area.

I used the same 1/16 balsa strips here except I glue them flat to the wing. I glue the sheet top and bottom and then this is where I add the strips. I stick one about an inch long with my exacto knife and glue the bottom side of it. then press it in place against the sheet and to the wing, make sense? Basically a former for the bottom of the sheet to glue to instead of just having the edge glued to the wing.

On the second side it's a bit more difficult. I only glue the bottom of the sheet in place so I can open the top to get my knife and the balsa strip inside like I did on the first half. When that's done, I glue the top in place and clamp it.

You'll notice I don't have many pictures of the processes just the result, but it seems I get on a roll building and forget to take a break for pictures.

Rebsix

My Feedback: (8)

The same steps for the front of the fuselage that were used on the rear.

1/16 balsa strips from the kit are glued to the top the full length of the fuselage and I sand everything smooth.

Rebsix

My Feedback: (8)

I found the rudder stock in the box and noticed one corner was crushed beyond repair, so I had to make a new one. Since I was wasting wood I figured why not waste more and make the rudder bigger?

The counter balance and the spruce stringer are glued on with medium using the waxed paper method and it's all sanded to shape. I also use a small block plane to get a bevel on the hinge line. Next time I have to remember to bevel the rudder before I glue the counter balance on.

Rebsix

My Feedback: (8)

Now I'm ready to hinge everything. I thought about adding counter balance tabs to the elevators but it isn't my airplane so I figured I'd better stay as true to the plans as possible.

I used CA hinges for all surfaces. I drill a 1/16 hole in the middle of the slot for the glue to wick into and they are as solid as any other type hinge. I'm only cutting the slots in this step, I glue them in after the plane is covered.

I don't care what anyone says about CA hinges, I have them in most of my airplanes and have never had a crash due to one failing.

The Slot Machine in the picture was something several people told me I "had" to get. I always used an exacto knife and a pick to cut slots until I ran a blade into my palm trying to slot some balsa that was too hard to cut a slot in. After using the Slot Machine I realize how dumb I was...twice. Once for cutting toward myself and sticking a blade in my palm to the hilt, and two for not buying a Slot Machine a long time ago.

Rebsix

My Feedback: (8)

Now I install the landing gear.

I measure, mark, and drill the gear and use it as a template to mark the plywood landing gear block. Measuring from the horizontal stab to the gear makes sure it's square with the fuselage.

then I tap the holes with a 1/4 20 tap and use thin CA to harden them. Four nylon bolts hold the gear on.

After looking at it, I always felt the gear isn't wide enough, it just doesn't look right. But that's what came with the kit and I didn't have a substitute.

Rebsix

My Feedback: (8)

I mentioned earlier that there would be more on the servo installation. The aileron servo is finally getting installed and after it was in I noticed it was interfering with the other two servos and the strip aileron horns were hitting the F-3 former. I couldn't move it forward because I didn't want to cut anymore on the wing to do so. I re-routed the rudder and elevator servos and cut some of the former out for clearance.

On the next one, I'll take a chance on the balance and move the rudder and elevator servos forward about 3/4 inch and it should solve everything. Theres just a lot of things going on in the back half of the cargo bay with all the servos, wing blocks, tubes, bolts, etc.

Only one pic due to all the head scratching during this step.

Rebsix

My Feedback: (8)

I almost skipped this step due to the complicated process but after it was done I'm glad I didn't. I was much easier that I thought it was going to be.

Before I mount the engine I like to get the mount itself installed then put the plane on the balance stand with the control surfaces temporarily installed . Then I slide the engine forward or backward to kind of semi-balance the plane. with an OS .60FX, 1/8 inch either way can make a few ounces difference in the final balance.

That being said, I've established the location of the engine and mounted it to the plane. There are two rings, or one disk and one ring, that come with the kit. There's a hole drilled in the front disk the size of the crank shaft and the back ring is the same size but it has about a 2 1/2 inch hole on it. The rings are tacked together with thin CA and bolted to the engine with the 2 3/4 inch spinner installed.

Now I cut and glue 1/4 inch balsa triangles and squares (experimentation needed here) until the entire engine is wrapped in the cowl. Theres a lot of carving going on to make access to the engine mount screws, needle valve, muffler, and whatever else is in the way, but the engine can be removed after the cowl is done.

I take the engine out, splitting the two 1/16 ply rings apart, and finish shaping and sanding while checking the shape with the spinner held in place. When it's done, the front disk is thrown away which leaves a perfect 1/16 inch space between the spinner and the cowl.

Rebsix

My Feedback: (8)

The wing tip blocks are glued on and sanded to shape, and the actual building process is complete.