VQ SBD Dauntless Repair Pt 5 - Wing Drawing

Added: 2026-05-23

[00:00:13]Hi, I'm RC Jim and welcome to my humble workshop, man cave, whatever.

[00:00:19]Well, we're continuing on our work on this damaged SBD dive bomber.

[00:00:25]And yeah, it's got a few issues with regard to the wing and so forth as you've seen from our other videos.

[00:00:33]And the thing is for us to be able to fill in everything that's missing on this particular wing, what we basically need is one of these guys.

[00:00:48]Yeah, the only problem is this is for a Super Decathlon and it's not for a uh Dauntless SBD VQ dive bomber.

[00:00:58]So, this video is on how we go about doing that and hey, it's not a particularly easy process, but it's something needs to be done to get this plane up and going again.

[00:01:09]Okay, let's have a good look at what is involved in uh making the drawing and getting the dimensions and so forth. So, I've made a little table here in my notebook with um dimensions for the various um parts of the uh rib in the wing.

[00:01:30]So, I've got the A, B, C, D, and E and uh each of the ribs on my chart here that I want the information for. So, 1 2 3 4 5 and 6.

[00:01:44]We've got this side piece together. You know, you're just using some scraps to hold things together.

[00:01:51]Um but using it such that I had a straight edge down here, so that's straight.

[00:01:57]And um I think everything is pretty close. It might be a millimeter farther out, just looking at that uh join right there.

[00:02:08]Um but pretty close to to what it actually is.

[00:02:13]What I've done is wherever I can, I've made measurements.

[00:02:17]And on the extra piece on the wing tip, I've actually got a separate wing tip, so as I actually to measure that very carefully with that separate piece out here.

[00:02:30]Okay, so having taken all the measurements, you know, the length and the height and the distance out and various things on everything that I could, I then I verified that our spar is perpendicular. So, I took my carpenter's square and I've got this such that on the front edge of the the uh plywood that is making up the spar coming out here, the leading edge side of that, I've got it cleared uh both in that bay and this bay.

[00:03:05]And so, just going up there, I can line it up with that and line it up here, and that's pretty well perpendicular.

[00:03:14]So, I know that in my drawing, I can start by laying out the uh spar, and then I can put measurements out in each way and uh be able to um position the um the various pieces.

[00:03:30]Now, I want to do that on a drawing because obviously, I can't be very accurate through most of this area as to what things are, but what's very accurate is the two ends.

[00:03:41]Those are very accurate, so when I lay this out on the paper, then I'll be able to measure precisely for each one of these what they need to be.

[00:03:51]Now, the next thing that is a big issue is how you go about measuring the profile of the swing.

[00:03:59]Well, that's where you need a little guy like this. And I say a little guy, what would be a lot better is if I had one that was long enough to cover the whole wing.

[00:04:07]But at least with this, I can get the front and the back, and I guess I could do the middle as well.

[00:04:14]And then be able to um to work out what it is.

[00:04:19]So, what you do is you push these all one direction.

[00:04:22]There's going to be this uh pointy edge down here that is going to be measuring things.

[00:04:28]So, I just get it to where it's going to be a little bit beyond there. I would do my best to have it horizontal as far as the uh overall cord of the wing is concerned.

[00:04:40]And I just push it down.

[00:04:42]Pick it up, and then I pull out the lever on the side.

[00:04:47]Now, that gives me the that profile, and then I can take a piece of paper, put the paper down, trace it with a pencil, and I've got that one.

[00:04:57]Do the same thing for the uh trailing edge.

[00:05:01]So, if I'm going with the trailing edge, and this works either direction, uh I can get up to the trailing edge here and push down.

[00:05:15]And it doesn't make any difference how far it goes as long as I've got it roughly.

[00:05:19]And of course, because I've put this I tried to have that horizontal, that should give me something to where when this edge here is even with the edge of the paper, and I trace that there, and I do the same for the other one, it'll give me to me pretty close.

[00:05:36]Okay.

[00:05:38]Uh so, we do that uh both top and bottom, fore and back on on each of those. I don't have to worry about this one cuz I can actually trace it on this one, and then I'm going to work between those two on the drawing to work out what the ones in the middle need to be.

[00:05:57]Now, we need to work out what materials we need. So, I've had a look at my drawings and I've had a look at what I've got here, and I've made a list of all the balsa pieces I need. I've got several packs of plywood, so I'm not too worried about that.

[00:06:14]But, but with the balsa, I'm not sure exactly what I have. So, especially for these big pieces on the leading edge, need to make sure I've got something for that.

[00:06:26]And I'm pretty sure I'll have the strips that I can do back here without too much of a worry.

[00:06:31]And then I am going to use plywood on these these bits in here, but I'm going to use the very thinnest plywood that I've got.

[00:06:40]And I've noted that inside here, the the ribs inside are uh quite open. You know, they it's just a little bit around the edges.

[00:06:55]Having recorded all of this information about the size and dimensions of the the ribs, I then laid it out in a drawing.

[00:07:06]Um so, I just taken two A3 sheets here and taped them together to get myself a piece of paper big enough.

[00:07:14]Uh and um so, I started out by saying, "Okay, this is a join to the center section of the wing."

[00:07:22]And then I drew a straight line out here for the edge of the spar, the plywood bit that goes out there as a spar.

[00:07:31]I then measured uh the dimensions out to the leading edge for the ones that I had, and then the total length of the the ribs going along.

[00:07:44]They didn't line up exactly as far as, you know, where the marks were, but I knew that the two ends would be certain cuz this one I could measure directly.

[00:07:54]And here on the end piece, I even have this right here that I could measure very carefully.

[00:08:01]Hence, I knew that that was right.

[00:08:03]I I had checked that this was perpendicular on the plane, which it is.

[00:08:09]And so then that gave me a great deal of confidence here.

[00:08:12]I had measured out the distance for each of these, and then I I laid it out first with just the dimensions that were there.

[00:08:22]And I measured the the distance between the ribs.

[00:08:26]And this distance here was a little bit shorter, but all of these were pretty well 90 mm. So, I decided I'm going to make those precisely 90 mm for each one of those and allow this one to be a little bit less given that this is thicker anyway.

[00:08:42]And it's also closer to the um root of the wing and needing a little bit more strength perhaps.

[00:08:50]Uh so, I allowed that one to be different and made these all identical.

[00:08:55]Uh so, that basically gave me the plan view of the wing.

[00:09:01]I then I went out to the garage and I made this uh sketch just over top of the wing so that the as I had the wing, you know, like so. That's the I printed out pictures of what I've got there to to refer to it.

[00:09:21]Um But anyway, basically I put this out there and then I put this up with the bits that I knew and saw that it was uh pretty close, you know? Looked like pretty well identical.

[00:09:36]So, that gave me a lot of assurance that you know, I've got it right.

[00:09:41]I then also took my um flaps.

[00:09:47]And I got the dive flaps here, and I've got the aileron and the wing tip there.

[00:09:56]And I set those in place.

[00:09:59]So, to me that's that's looking pretty good. And just verifying it looks like it's lining up, you know, the right dimensions and so forth. So, I'm just checking as many things as I can as I go to make sure I've got it right.

[00:10:13]So, then the next thing was coming up with a shape of the um airfoil.

[00:10:20]So, for the ribs, just what sort of shape are we going to have?

[00:10:24]So, what I did is I started out with the the big one, the one where it attaches to the center section of the wing.

[00:10:32]And of course, I didn't have all of this here. So, I draw a straight line, and then I marked out where the uh front of the spar would be. So, that's that line there.

[00:10:45]So, I measured the distance back and the total thing. So, I put a mark out here and a mark there. So, I've got a X across here with a mark there and a mark there. I then measured the height of it here.

[00:10:56]I measured the height of it there. Those were things that I'd measured um off the plane.

[00:11:03]So, I've got a point here, point there, point there, here, here, and there.

[00:11:07]Then, I took the um the uh forms that I had.

[00:11:16]I'm missing one of them.

[00:11:18]But anyway, this is the bottom of the wing.

[00:11:21]And so, I said, "Okay, I've got to match up with the point here and the point there, you know?" So, I I got that to where it looked like it was about right.

[00:11:30]And um I've got the point here and the point there.

[00:11:35]So, I realized that this didn't quite go the same length as that. And so, I played around with these to get them to to line up a bit. And I also had to play around with just exactly where it would be top and bottom. And after a few attempts, I finally got it to where um it looked to me like it was pretty well complete, you know. And then there was one more piece back here.

[00:12:05]So, I used that to get the shape.

[00:12:09]Having done that for the the large one, for the one next to the center section, I then traced out from the end of this thing here, put it down on a piece of paper, and this one right here, traced that on the paper, cut that out, and then I used that, and I marked on it where the front of the spar would be.

[00:12:31]And then I put that in there, and I traced that out, and that forms the smallest one.

[00:12:38]So, then what I did from that point is for several places, so, here, here, here, here, here, here, and so forth, all the way around, all of those places, I measured the distance, divided it by five, and then did my best to mark out where the lines would be, you know, uh going across there.

[00:13:02]Okay.

[00:13:03]So, that gives me all of the the six different 1 2 3 4 5 6, yeah, the six different airfoil shapes that I need for each of the ribs.

[00:13:15]Now, these are all outside dimensions.

[00:13:17]It's the outside of the profile, so I'm going to have to subtract off of those the material thickness for uh whatever balsa sheeting is going to go on there.

[00:13:28]But, that's basically going to give me it.

[00:13:31]So, what I will do next is I'm going to mark out where the notch would be for the piece of balsa, the 6 by 6 balsa that's going to go lengthwise top and bottom.

[00:13:44]And also allow the thickness for the plywood um spar that's that's going through there.

[00:13:53]And then I'll add on the um Well, maybe I'll just say I've got to subtract thicknesses off of these anyway. So, each individual one I will uh mark as far as after I get them cut out I'm then going to mark minus the material thicknesses, you know, to modify them according to that.

[00:14:19]Um just a little bit too many lines on here to think about doing all of that on on this drawing. So, then I'm going to photocopy this um and I'll make a dozen photocopies of this.

[00:14:33]And well, I guess I just need to do six photocopies, and then I'll just use each one two times.

[00:14:40]Um So, after I've got the six photocopies, I'll then cut out one of the six um um outlines uh on each of those sheets, and then that will give me the thing to work with.

[00:14:56]And then I'll subtract the material thicknesses off of them.

[00:15:01]And uh come up with what I think is, you know, looking pretty good.

[00:15:05]And uh then we'll take it from there.

[00:15:08]Bit complicated, but I think that's what we have to do.

[00:15:12]Well, we're well underway and getting this plan done and almost ready to start cutting some balsa and plywood and uh getting some things built on that wing.

[00:15:23]And of course, once you get the wing done, then hey, it's just installing some hardware and and off we go up flying again. This is one of those projects that uh takes a lot of work, but it'll be so rewarding when we get it complete.

[00:15:37]Well, if you haven't done so already, make sure you subscribe. Have a look at some of the other videos on our channel.

[00:15:43]Put your comments in down below. Ring the old bell and uh hey, enjoy your flying and your building and repairing and have a great day.