Wow, it's easy to get behind in the posts. So far I've got a good portion of the left wing built but I haven't shown you all anything yet. So it's time to correct that. I'll run through the steps as they are laid out in the instructions. As I proceed with this build this may be the way it goes. I may go a bit without any build posts, and then I'll post a large number in a row. As I said before, each post will be limited the the number of pictures I can post at one time.

As we get ready to lay out the ribs I want to retype a note that is printed in the instructions:

There is a very good reason why I wanted to re-type this warning from the instructions. A lot of the time new builders will look at the plans and consider them “gospel”, and in some cases that can be bad. In this case, if you line up the ribs with the plans there is a very good chance that your wing will turn out warped or crooked. In this case use the trailing edge(TE) as a starting point, and then layout your ribs using the TE as guide. As you lay out each rib make sure that the distance between the ribs stays constant all the way through the length of the rib. Although the instructions didn't mention this in advance, there is a very good guide that you can use that will simplify laying out the ribs. The shear webs. All of the wing bays, with the exception of the last two outer bays, have shear webbing between each rib. Since this is the case you can glue the shear web to an installed rib, put the end of the rib in the notch in the TE, and then set the rib on the rear and main spar correctly by seating the rib firmly against the installed shear web. Don't worry if this sounds confusing. It will all become clearer as we start laying out the wing, also you can refer to the pictures to see what I am talking about. But what I am saying is that sometimes you have to use the plans a guide instead of “gospel” in laying out what you are building. Reading the instructions and looking at the plans before starting to build will usually help you realize that you may have to “fudge” from the plans a bit to get a good build.

There are 5 different ribs that will be used on the wing, W1-W5, so we will want to make sure that we have the in the proper order before we start setting the ribs. W1 is the root rib, meaning that it is the very center rib. W1 (root rib) of each wing panel will be butted up against each other. Then moving from the center of the wing panel the next ribs in order will be W2, W3, and W4. Then from that point to the outside of the wing all the ribs will be identical, being the W5 rib. It needs to be noted that ribs W2 and W3 are a little smaller than the rest of the ribs. This is because they will have balsa sheeting over them when the wing it constructed. What I like to do at this point is pull out all of the ribs I will need for this wing panel, and then lay them out in the order they will be in on the wing (see picture #1)

Ok, let's start laying out the ribs. The instructions tell us to set ribs W2 and W3 first. Since the notch in the TE didn't line up exactly with the plans, and taking into account the note from the instructions I posted above, I chose to start with the W3 rib. The reason why I wanted to start with this rib is because we have already laid out the sheeting that will cover W3 and W2, and since this sheeting covered the printed plan below there was no reference point for me to put down the W2 rib. Whereas if I put down the W3 rib first I could then use that as reference for placing the W2 rib. The best reference point that I can recommend is the actual line for the root rib (will be the far right side of the wing). I guess you could have done the same thing and place the W2 rib first, but I don't think it would really matter. So whichever way works best for you I'd say go for it.

Picture #2 shows a test fit of the rib over the already applied sheeting. As I said in my previous post, you want to make sure the fit is tight here. Another quick note, glue cannot fill a gap, Any gap you have where parts join will weaken the overall structure of the wing, so you want to try and get your parts as tight fitting as you can. When you are test fitting the part you will want to mark it's final location because we will need to remove the part to apply glue (this won't aply if you are using CA. You can just leave it in place). Since I have to wait for glue to dry I prefer to do several parts at once, and then wait for the glue to dry. In this case I want to glue in W3 and W2 and the same time so I can weight them down while they dry. With W3 dry fit in place measure the distance on the TE between the notches for W3 and W2. Move up to the rear spar and mark the same distance, and do the same thing on the main spar. This will give you the location for the W2 rib. As with the W3 rib you will want to test fit the rib to ensure a tight fit on the spars and the sheeting. When you are satisfied with the fit mark the location for the W2 also. Once you are satisfied with the fit of the W3 and W2 rib apply a bead of glue along it's edge (picture #5) and put it in place on the location marks you made. Once the glue was applied and both ribs are placed in location I double checked the alignment for both ribs. Satisfied that both ribs are in place I put a sheet of scrap balsa wood on top of the ribs, then placed a couple of weight bags to hold the ribs in position while the glue dried. I wanted them to have some weight so the joint with the sheeting was a tight bond.

Since this is where I stopped for the evening while I was building I will wrap up this post so I can it up on RCU. As soon as this is posted I will start writing up the next posts. Like I said at the start, I have a lot to write up.

On the next post I'll work on spacing the ribs and shear webs on the spars.

Pictures
1. Laying out all ribs in the order they will be installed
2. Test fitting rib W3 to ensure a tight fit on the spar and with the balsa sheeting already in place.
3. Another shot of test fitting.
4. A 3rd shot of the test fit.
5. Applying a bead of glue on the rib before setting it in place.
6. Using weight bags to hold the ribs W3 and W2 in place while the glue dries.


Until next time

Ken