Fitting the wing together.
I use these clamps in the assembly. They are easiy to find in any office-tools-catalog. I ordered 180 and I had to pay about 60 euros. (anno 2005)
After placing the ribs on the spars and putting it all on those blue rests, it is time to line it up. Make sure that you marked the middle of each spar and the middle of the trailing and leading edge.
Our ribs were not completely straight. The trailing edge was not in line. It was corrected by placing this triangles with those clamps.
The ribs were placed, but they always turned sideways at the bottom. To prevent this during the last controls, we did make small triangles and fixed the bottom of the ribs with them. Now it all stayed on its place.
You need to measure the distance of the parts towards the ground. First control the spars. Measure it left and right. Must be the same. Our error was 1mm on distance of 4m. Good enough. Now do the leading and trailing edge. We had a error in the middle of the trailing edge. Came from the triangular part we added earlier. Made the choice to glue only the ribs and the edges later. We could not line up and glue trailing edge at once.
Luckily Hans Engels did visit and gave us a LOT of advice. Thanks Hans, without you we would have made a few errors. Bad errors.
These are the parts I still had fromt he first set of rib-making. We used them now to glue the ribs. First ... cut them on size. Must fit in between the caps. 4 versions. One at front spar front, 1 at front spar rear, 1 at rear spar front, 1 at rear spar rear. Mark them somehow. Prevents errors.
Stefan (glueing-pistol) and Milko (blue gloves) added the glue here. You need to glue the side with the gap and one short side.
Karel-Marc helps in a easier pose. Holding the parts and touching with your hands some surface makes you tremble less. Much easier.
Here you see one such part glued. Location: I guess ... ribs at the hinge-line. Part at front of front spar. Normally you need 8 parts for each rib. You need to glue EVERY SIDE (left and right, rear and front).
Here are two parts glued at now fixed with a office-clamp. NOTE: THE REAR SIDE WAS NOT YET DONE. See the later pictures to see where you need to glue.
OK, the hingeline-ribs are different. They are two ribs at the same place. Place about 3 mm between them. Just enough to let a saw pass. You cannot glue the ribs fromt he inside here. You need to do it after you cut the wing in three parts at the hinge-line. Our clamp was too small to cover this distance. Luckily I had already these larger plastic clamps.
Location: backside of rear spar. This spar is open at the rear. You can easily line the parts with the reinforcement of the spar. The reinforcement should be the same size as the two parts and the plywood together to make the lining easy.
All ribs are glued to the spars. Time to ... clean your hands. I suggest that you use gloves or wash your hands each 30 minutes. Why ? Structan-glue makes your fingers BLACK. Washing at the end does not help. After 1/2 hour it already starts. If you are looking for a good name for a club that makes wooden airplanes, just use "Black Hands". You will later understand why.
There was just enough time to discuss one item that makes a large difference between my project and another Flying Flea. I need to place triangles in my wings. Here we see what Hans Opinion is. I guess you cansee where we are heading to. Wooden parts go over two holes. They pass through a rib-weigh-reducing-hole. It has to be altered a bit. The parts will be glued to the caps of the ribs and there will be a extra plywood to reinforce the rib again under the newly hole in the ribs plywood.Here you see two of the four decompressionstruts in preparation. I didn't place them in the holes just next to the hinges out of fear to make the placement of the hinges more difficult.
As you see, the wooden parts have to go through a rib. You need to cut some hole in it to make it possible. DON'T FORGET. Later you need to glue the rib to the decompressionstrut to give it back its rigidity.
Clamping the plywood against the parts needs a bit preparation. There are two areas where you need to have some extra tool. In this corner I could not place a clamp. So I use two wedges. I press the larger one against the plate and fix it with the little one on the other side. Look out! Don't glue the wedges against the plates! Use paper between both.
Here is the other area where you need to have a tool. Clamping is impossible without this triangular shaped block of wood. Keep it on its place by plcing a small part between the block and the rib-glueing parts.
Two decompression strut are finished. Still needs some finishing AND to glue the ribs onto the decompression struts to fix that hole you made into the rib. You can also see what tool I am going to use to keep the trailing edge on its place while glueing thetrailing edge tothe ribs. I will remove it once the sides of the wings have a plywood plate to keep the wing in its shape. Later more about that.
We glued the parts between the ribs on top of the front spar. Today we glued the lower parts. This operation took hold of ALL the clamps in our workshop. We even had to improvise .... . Later more about that.
First we thought about doing both sides at once. But I feared major problems with sliding sticks. Luckily we didn't do both. Those sticks slide on that glue! Here you can also see that we use clamps to hold the ends of TWO sticks. Saves a lot of clamps!
I said ... we had to improvise. One student put glue on a part and ... we were out of clamps. So we used cord to tighten it. A simple knot and a small stick. Put the stick in the circle of the rope and turn, turn, turn till it is TIGHT. Fix somehow the stick in that position (we used one of our office-clamps). I was thinking about using this system for the rest. But I saw that it is hard to keep the stick at the edge of the spar. I wants to slide further to the middle.
We wanted to at last finish the rear spar. First we place the wing level. To control this. We used that centerline on the rib. I knew it would have a purpose! Just place a plate under that line and ... (hey, Stefan, look at the line! Is there some pretty girl passing by?)
...put that level-tool on it. We used a central rib for this measuring.
We placed a clamp on the two caps of the rear spar which were not yet covered. We placed a rib at the place where I still didn't know the right place of the rear spar and controlled if the centerline was level. If not we changed the position of the caps a bit. Make sure that you position the rib in its proper place. Have it fixed there somehow. We worked up-side-down, but the actual top of the rib-caps have to touch the spar! Makes it much easier on a later step in construction.
Ok, all is level. Slide the rib towards the others and take a piece of paper. Draw the outlines of the caps on that paper and cut it out of plywood. Now ...glue!
almost forgot to mention. Found a easy way to correct the placement of the trailing edge. It was about 1 cm out of center. We pulled it right with a rope. The sam system as we used to tighten a stick onto the spar. EASY! Many will recognise this system as the way to stop the bleeding in a leg or arm. Touricette was the name of that EHBO-thing.
the volenteers are busy getting the small stick on top of the spar at the right height. We first drew a line from cap top to cap top on that part and filed just to the line. Euh ... with 6 volunteers the work progressed fast enough. ;^)
There was not yep a groups-picture. So here is one with the volunteers of that day. We are missing a few on this picture. Front line (kneeling)(left to right): Karel-Marc, Sam. Standing (left to right): Jeroen, Thijs, Stefan, me and Ian. Ian, Thijs and Sam are the newest members. Karel-Marc and Stefan are already sure to go to St. Andre de l' Eure. Me too.
if you recall how we first measured if a rib was placed correctly (I guess it was picture c_openpou_3), well, this is easier! Just clamp that tool onto the rib and you can do the job without help. I am now using it constantly to place ribs. But ... I need to say that placing all at once does seem even easier. Will try to find a solution to have it done that way in the rear wing.
This is how I made the rounded parts for the wing tips. It is just the same system as Hans Engels. I took a waterproof plate of 18 mm and 5 spruce parts of 20 x 3 mm. The most easy way to place them is to glue them first on to each other and take them to the template. Fix it at one end and slowly fix the rest clamp by clamp.Be sure not to go fix the clamps randomly. You need to follow a direction. Example of BAD: first clamp 1, then 3, then 2. No no, 1, 2, 3, ...!
This is a useful tool. A Power Phile. Reduces the work of getting parts at the right seize after glueing. I have it now 5 days and it proved to be a reeeaaal good asset in a workshop.Kevin is inspecting the clamps on a compression-strut and thinks "A job well done" . Jeroen looks sideways and sees the work still to do. Expression on his face tells it all.
The rounded tip is nearly finished. Already a beauty to my humble opinion. Note the foam plate in the corner. Was needed to keep the leading edge on its place. The forces in the bended part slided the leadingedge 1 cm from its normal place (sideways). The foam solved the problem and it did also solve the possible problem of a rather small gleuing area between leading edge and round parts. Had a few troubles there. The rounded part is at a larger angle than first hoped. Not like Hans system.
To try another system with the glueing of the plywwod on the rear spar, I didn't place the last part. Hoping to be able to force the tip a little more upwards when the glue is dry. If not possible, the four points of the rounded tip will not be in a single plane and I will have to use the cutt-glue system again. Hope not.
Maybe it is visible that the rear spar tip needs to be lifted up to get the four points in a single plane.
Here you can see the cut-glue system I used to get the tip of the rear spar a bit higher. I just glued two parts onto the old ones and shaped them a bit after the hardening. I still need to place the gusset on the underside here.
The front spar seen from the back. Two gussets installed (2,5 mm).
Here you see the fake ribs in the center of the leading edge. Yes, indeed. three parts! I used the triangles to avoid the displacement of the leading edge. Due to the thin caps of the ribs, the leading edge tended to move sideways. It no longer does now. The central part is needed to give the support for the "arm" to the front to which the Open Pou stick will be connected to steer the pitch. Go see the concept drawing.
Busy adjusting the bended wingtip to be glued on top of the trailing edge. Because the trailing edge is at a angle with the wingtip I canjust adjust the wingtip at a angle to glue it just on top of the trailing edge part. Much easier than the system I used at the other side!
Here you see how I connect the bend wingtip part with the trailing edge. A top view.
my hotwire box. You can see the small black transformator which I used first. It did not cut at all. Not powerfull enough. With the white 16A tranformator (4x powerfull as first) cut nice at lengths of 50 cm. I tried to dim the current. But, it did not work. Seems that the dimer needs at least a few watts before it starts to work. Need to find another solution when I am going to use a larger transformator. I want to cut the foam-wings for my RC-hobby. A bit longer wings.
The gussets on the tip of the front spar.
Here you see the solution I had to correct the position of the tip of the rear spar. I glued the new part on top of the old part. Once hardened I cut the rest of the old part and did the same on the lower cap. I changed my system on the other side. Later more about that.
The leading edge in the center. I needed to strenghten the area because due to the slim ribs the leading edge moves the 1 cm sideways. The foam was glued to the spar. The two outerside parts had not yet a connection with the center foam. Later I glued small parts in front of these to make the contact between their fronts and the center foam part. The nails are there to keep it at the same height during hardening the glue.
My version of the hotwire holder. Based on what I saw at Hans Engels.
A system to control the position once the glue was hardened. It was no longer possible to place the L onto the leading edge. I now simply clamped it onto the wooden part. I placed the part onto the centerlines and if the L was at the centerline of the leading edge, then it would be OK. And ... it was OK.
My new system of making the tip of the rear spar. I placed the rib and controlled its levelnes if the rest of the wings ribs was level, then I clamped the caps to keep it on its place. Next I glued the plywood onto the caps. The last end I would do once I had the last rib was installed. I was able to keep the under-cap intact.
Ian puts water on the outside of the already cut-out plywood. While he was doing that ...
... we put the wing as its "tail" and held it with two of the supports and some ropes.
... Stefan and I "varnished" the internal parts of the leading edge with the same glue as he use to glue parts together. Euh ... it was a hell of a job. Next time I varnish normally.
Ian is ready with the water and the result canbe seen. When we turn the plywood upside-down, you can see the bending it does by itself. This helps during the glueing to prevent cracking the plywood.
Ian varnishes the inside of the plywood of the leading edge with the glue. Very easy to do and I would do it again. But things with corners..... no way.
Stefan is adding glue to the parts that will touch the leading edge plywood.
Ian and Stefan are hamering on the staples. I used those stamples to have more assurance that the plywood will be and stay on its right position. Hans Engels didn' t do it in his demo. I thought it was needed. My plywood bend by itself a bit away from the glueingcontact areas.
Above each rib is a tense kind of rope. Note the central "rope". There is no rib, but there is that central fake rib. I wanted that the leading edge would be perfect on that place too.
I put with a drill a hole in the fake ribs. I wanted to be sure that the air would not be caged in the leading edge. To prevent air-compression-explosions of the leading edge, I placed those holes.
After the central part was glued I noticed that on the other part I could move the plywood a bit at the underside of the airfoil. The "rope" couldn't keep the plywood onto the ribs. I solved it with stapling the plywood on all the ribs and by adding some plates at the underside to give more pressure onto the plywood so it would touch and press the ribs.
Being divorced I can work even in the weekends on the glider. The weekends I have the kids I take them with me. They both amuse tehmselfs by using all kinds of basic tools. Here Jonathan is really enjoying his work with a tiny saw. He wears a overall of a 14 years old kid. It was fun to see them "working". they enjoyed my working hours on the glider.
That Powerphile of Black and Decker really is a good tool. Making the trailing edge triangular would take for ever if I would have done it with a phile or sandpaper. Here it can be done very quickly by Karel-Marc. Just be sure to place that lines to which it has to be shaped.
Jeroen varnishes the rest of the wing. We used Yacht-varnish for the parts. Later I found out that the Diatex-pre-glueing-product canbe used to as a varnish. Itstead of using two products, I could have used ONE. If I only knew that earlier. A mistake I will not make on the second wing.
We placed the blocks to get the connection-metals (which hold the wing parts together) at the level of the plywood.
Drilling the holes in the spar for the connection-metals is not easy. Takes some preparation. Here we are using a column-drill and place its column perfectly vertical.
The volunteers (Thijs, Stefan, Sam, Jeroen) check if the wing is placed horizontal. We also did check if the spars side was placed vertical. If yes ...
... you can drill the holes and be assued that the holes are perfectly lines with the spar. It is a way rather was rather easy. But ... I would suggest that the next time I will place those holes when the spar still stands alone without the ribs. Note: see the long drill we needed?
Due to the vertical placement of the drill and the spar, we were not able to drill with the column-drill the entire hole. We had to use a hand-drill be complete the holes. We used the already drilled part as a guide for the rest of the drilling.
Two volunteers and a teacher who are happy that the holes are drilled. You may be able to see that the holes nearest the double ribs are 8mm, the rest are 6mm.
Sadly ...after this the project ended due to problems with the direction of my school.  :-/  The wing is still in my garage and it is hoping for a museum where it can be shown as a "wooden wing made by kids for kids".