Jonny Quest "Dragonfly III"

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I'm getting closer by the hour. I hit some little areas with spot putty and sanded those down using a 150 grit sanding sponge. I've now shifted over to grey primer.It's about 98% there with a couple of small high spots to work out . One problem I have run into is about a dozen little spots, maybe 1/8 inch across for the largest, that appear to be some kind of bubble in the glass. they can be depressed with a fingernail and then pop back up. They are too soft to sand out. The best bet might be to puncture them with an Exact-o knife and then fill with a drop of epoxy. Sanding down the remaining area should be easy enough. With any luck I'll have that operation done by this evening. --20160830_082402.jpg20160830_082418.jpg20160830_122430.jpg
 
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Don't know how I missed this build over the last couple years but Looking very good HD!

Glad to see I'm not the only one that has projects setting round for multi years LOL!
 
Don't know how I missed this build over the last couple years but Looking very good HD!

Glad to see I'm not the only one that has projects setting round for multi years LOL!
Yea, usually I manage to go from start to finish but this one got the better of me and I set it down. That was likely a good idea since I changed direction from a bg to a standard rocket in the interim. I did get the fix in on those little spots. I ended up punching little holes in them and depressing them with a chop stick. After that I put a drop of 5 min epoxy in each one. That was followed by a light sanding to get them level and some glazing putty. Sanded them down and primed and they are gone. In the process I discovered a bad area on the starboard lower rear. There are two or three spots where the skin is just thin and flexible. I'll wait till tomorrow to deal with that. I guess the best bet--since the area is a total of about six inches long by about 1/2 inch wide--- is to cut out the skin.It looks like the glass did not adhere to the foam in this area. I think the best approach will be to pour some epoxy resin on the area. Once that has set up I'll put a layer or two of FG resin over that. At that point I should be able to feather out the edges and fill any low areas with glazing putty and sand smooth. I'll get some pics out of that process tomorrow.Not a real big deal but a PIA and unexpected. I did wet sand the rest of the rocket and I don't have any other issues that I can find. Once ALL OF THIS BUFFOONERY IS BEHIND US--I'll get down to the good stuff--later, H
 
Well,I guess I have to show the bad with the good. Maybe this will help someone out in the future. I cut out the bad spots with an Exact-o knife--20160831_100937.jpg--I opted to cut out the individual spots instead of the entire area. Next I poured 5 min. epoxy in each spot until it was just over level---20160831_101426.jpg next ,after about 30 min. I went back with a blade and shaved the top of the epoxy off until it was nearly level--20160831_112115.jpg--this was followed by sanding the entire area with 60 grit--20160831_114524.jpg--that was followed up by glazing putty sanded and primed---20160831_114721.jpg20160831_152826.jpg--since I was working it the tail area anyway , I went ahead and used a Dremel to cut out the tail cone area to shape--20160831_145821.jpg- I think the area should turn out ok when I'm done sanding---And that's how you fix a complete screw-up!!---H
 
The phrase "ya gotta crack a few eggs to make an omelette" comes to mind. Your omelettes turn out pretty good. :)
 
Thanks samb, I just got done sanding on it and did a re-prime. It turned out better than I had hoped--I had my doubts--NOW, we can move forward !!
 
I'm finally pretty pleased with the fuselage and now we can put that behind us for a while. The next thing on the agenda is to core out the fuselage. This is gonna be a challenge. Normally I would cut out chunks and then power sand the interior smooth much like I did on the 20 mill project. That ain't gonna happen here. First, it's to narrow , at 3-4 inches across , so I can't really get my hand in there. It's also a much longer area to core and it's a bit more delicate than the 20 mill I think and it does take some pressure and muscling to do it that way. I'm not going to chemically core it out. It's messy and potentially dangerous--so that's out. I'm gonna sit back tonight and listen to some tunes and think about it. I'm sure by tomorrow I will have come up with some procedure or make some tool to do the job--stay tuned--this could get interesting----H
 
I finally came up with a plan to core out the bird. After going through a bunch of ideas I finally came up with this. For about 7 bucks I could take all this-20160904_100029.jpg--and turn it into this---20160904_104016.jpg---I could attach it to my drill and do this--20160904_105121.jpg---It was going to make a mess but it was a controlled mess !!. I started from the rear and all was going well until I got about half way through and I ground a small area through the skin. I caught it early enough so it's not a tragedy. ---20160904_110802.jpg--Any of the other ideas I had would likely have done a lot more damage so I'll live with a little fix !!!As soon as I saw this I stopped and figured I better go ahead and cut the nose off and start again from the other end---I used a Dremel to cut the skin and followed that up with a hack saw blade--20160904_110806.jpg-20160904_111944.jpg---after a little more work --a nice 3 inch hole all the way through.--20160904_123926.jpg--- I wanted to smooth things up a bit so I cut a couple slots in my new high tech tool and slid some triple folded sand paper through them and --WALLA !! A custom flap sander !!--20160904_115128.jpgAll in all it came out AS PLANNED and only took about an hour from start to finish. I'm going to glass some areas inside the skin to strengthen them and then get started on the mmt.---H
 
I'm gonna hold off on doing any glassing inside until I get the mmt. ready to install. It looks like some of the areas that needed some glassing are right where I'll cut for the fins so, why do the extra work? The mmt. , fins , chute canister, puffer tube, and tail cone/burner can all need to be assembled together as one unit. The fins/wings and tail are connected directly to the mmt/ puffer tube to assure alignment down the thrust line. You have to "fly the wing" as they say. This whole process is likely to take a couple days. I decided to make the fins out of 1/4 inch foam board and put a balsa leading and trailing edge on them---here's what I'll need--20160905_132548.jpg--I went ahead and popped a line down the spine for the tail. The wings will be mounted to the mmt and that line will be marked later for cutting----20160905_083738.jpg--I did get ahead of myself earlier and cut the nose off before doing this---No problem I just re-aligned it and taped it in place. I've gotten the wings and tail cut out . When cutting this foam it's always best to have a new blade in to avoid frays---20160905_141028.jpg20160905_141845.jpg20160905_141958.jpg--- I ended up re-cutting the tail a bit smaller while it was about right for the cartoon it was distractingly large on the model so I shaved it--20160905_160640.jpg---you'll notice the curved blade on the knife. This allowed me to pull the blade while cutting and use a finger as a guide along the original edge so I could free hand the new cut.. More later---H
 
....you'll notice the curved blade on the knife. This allowed me to pull the blade while cutting and use a finger as a guide along the original edge so I could free hand the new cut.. More later---H
..sounds like trouble.
Mellon season up these parts.
Early crop for U!
Another um.....master build.
 
It's time to try and destroy the rocket !!I need to build the mmt, mount the wings and tail to it, get the length right,chop up the fuselage so I can slide the whole thing in and hope it aligns with the chute canister at the other end!If that's not enough I'll do a dozen dry fits, make some "eyeball" cuts, all this while working in the cool yet tight confines of my kitchen!! Stay tuned, back in a few---H
 
First things first, I needed to get the wings epoxied together. On the program, the Dragonfly had a very exaggerated dihedral. I didn't care much for that and I assumed it was going to give me problems with stability so I backed it off a bit---20160906_131806.jpg20160906_131850.jpg20160906_132525.jpg-- I started by taping the top of the joint(this would be removed later). After that I flipped it over and poured epoxy into the joint. I put a small block under the joint to get some dihedral. While this was drying I did a dry fit or two or three of the mmt to check for length and alignment----20160905_232540.jpg20160905_232611.jpg--looks a little rough now, hence the term "rough out"--more in a bit--H
 
Sorry about that little delay. Daddy has to eat! Once I was satisfied with the length of the mmt. I mounted the wings and tail. I added another wrap around the mmt so the wing and tail would fit flush. I needed to match the thickness of the coupler so everything stayed aligned. I did need to notch the tail for the burner can and the chute canister.--HMM seems I didn't take pics of that, no big deal, I'll pull it out later and get those off to ya'll. I pulled a few measurements and proceeded to use my Dremel to cut slots for the wings and tail in the fuselage. I really, really,really expected this part to go bad but it went smoothly and in fact I only needed to clean up a little bit of the wing slots for the whole thing to slide in smoothly. I next inserted the chute canister in the front and the friggin thing fit like a 13th street hooker.-20160906_155148.jpg20160906_160900.jpg20160906_162416.jpg20160906_162616.jpg20160906_163536.jpg20160906_163614.jpg20160906_163624.jpg---That's all that's gonna happen today. I'm out of epoxy and I need to plan the leading and trailing edges out. I'll disassemble everything now and get a coat of resin on the mmt.tube to strengthen it. After that, I'll glass over the weak spots under the skin. I should be able to get everything mounted and epoxied in tomorrow. After that I'll focus on getting the nose cone aligned and the lugs installed( I'll be using the intake on this one---Later, H
 
..sounds like trouble.
Mellon season up these parts.
Early crop for U!
Another um.....master build.

Yep!! Been havin mellon coffee every day for a week now !! Got enough to last the winter I think !! Love the contest Bro. I'll vote today. Not sure I'd call this a master build, more like a : throw'em in the deep end, let's see if he can swim " build !---Later--H
 
Well, it's 5 am and I'm wide awake. What's on the menu today? The first thing I need to do is clean this place up. I'm out of control and too disorganized !! After that, a couple more test fits and tweak it as needed. I need to get the shock cord mounted on the chute canister before it's installed. I'll also address any weak areas in the skin today. I will begin the lug installation today--I need to get that figured out before I get much further. I might go ahead and begin sanding on the leading and trailing edges of the fins today. I'd like to get the worst of that out of the way before I install them.That's probably enough for one day. If I get that done early enough I'll attempt the insertion of the mmt assembly. Oh yea, speaking of that, here's the pics I promised----20160907_031553.jpg20160907_031606.jpg---H
 
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So what got done today? Well not everything I expected and not in order but progress was made. I did sand on the leading and trailing edge balsa. That will be installed later after filling and sanding. I hope to minimize any extra work on the foam wings. I finalized assembly of the chute canister. It has two bulkheads about 1 inch apart mounted to the rear of the canister. Two bulkheads helped with alignment and overall strength. I did fish some cord through in a loop as an attachment point for the recovery gear. The puffer tube you see in the final pic will be cut off flush with the rear bulkhead at a later date.---20160907_184116.jpg20160907_184657.jpg20160907_184841.jpg20160907_184959.jpg--I did add a sleeve over the front of the canister to help with alignment and to get it closer to the skin. Back towards the rear, I went ahead and made a wrap of corrugated card stock to mimic a burner can. I also added a sleeve on this part of the assembly to help with fit. First I slid the rear assembly in and then the canister was placed in the front and glued to the puffer tube next the second bulkhead was placed and glued into position. The completed assembly was shifted back about 1/4 inch for a foam plate that will help align the nose later----20160907_185922.jpg20160907_190654.jpg20160907_193237.jpg20160907_201838.jpg--Tomorrow I'll get all this epoxied in place---there's no going back now!!--and I can start to deal with the nose cone alignment and the lug placement. More later but now it's time for sleep--H
 
I actually feel like I made some progress today. The mmt/canister is epoxied in place. It was time to tackle the nose. Getting this aligned could be difficult since it's not your standard round cross section. I fashioned a foam bulkhead and temporarily inset it in front of the chute canister. This was followed by cutting out the center. I could --in theory--used this as a pattern on the base of the cone to mount a shoulder. I cut a grove for the shoulder in the cone. I purposely over cut this a bit so there would be some play if I needed it. Next I took the pattern and epoxied it in place in the fuselage. I applied a little epoxy in the groove in the cone and set the shoulder in. That was followed by placing it in the fuselage collar. I had to work quickly since I was using 5 minute epoxy. Once it was set in I made a quick adjustment and held it in place. Unbelievably, it worked !!!! I now just need to clean up all the rough cuts !!--20160908_105305.jpg--20160908_110213.jpg--20160908_121408.jpg--20160908_121603.jpg---this is a good pic showing the large size of the Dragonfly---20160908_140319.jpg---I'll be spending the rest of the day cleaning up the rough cuts and measuring for the canards---H
 
It seems the nose of the Dragonfly wants to droop when held level. The nose does not weigh much --odd--I thought I had a good snug fit around the shoulder/ collar area--seems not! Well, after some detective work, it seems I fit the shoulder to a piece of bt that was from a different maker than the one I used in the canister. The wall thickness was just a tick THICKER--.This made the shoulder smaller than needed. To make matters worse, the canister had a tiny-tiny-tiny lip on it , so it felt tight going in vertically. I cleaned up the edge of the canister. Next I added masking tape to the shoulder to make up the difference in space. That seemed to work but it's a half ass way of solving the problem! I'm going to sleep on the problem but right now I'm thinking about putting a layer or two of resin on the shoulder. I may do the same to the inside of the canister. If I get it too tight I can sand on it until it's right. Ah well, live and learn!!In the big scheme of things, if this is the worst I have to deal with, it's a good day. Later---H
 
Before I jumped in feet first and started putting resin on everything I decided to look at the problem some more. I cut a piece of poster board the width of the shoulder and taped it tightly to it. It slid in with just a little resistance and the nose still sags---%$#^---I wrapped another piece around and with some effort was able to get it in. Well that's not going to work but it caused another problem to surface. The nose is now out of alignment and the skins don't match up--%&#^---After some playing around and seeing where it was misaligned I decided to take off the second layer of poster paper(it was too tight anyway). I taped a piece that wrapped about a quarter of the way around to the lower left corner of the shoulder. That seems to have taken care of the problem. No sag and it's pretty firm but not so much that it makes me worry. I'll probably go with this as the fix instead of resin.--It will be glued in place not taped-- I may add a lock and pin to the top as a safety measure. The main problem being, the nose has the canard wings on it and they need to be PERFECTLY aligned with the main wing. Any shift in the nose would be disastrous.Well, like I said before, if this is the only bad problem I have on a project like this , then I'm having a good day!!Not much will happen over the next couple of days, I have a lot on my plate. Later--H
 
Is there any room to put some three or four pegs circumferentially around the base of the nose cone section? I am on iPad so can't draw them, but thinking pegs on one side and fitted tubes/receptacles on the other. From what you describe, nose not only can't be allowed to sag but also can't be allowed to rotate. Pegs may solve both problems.
 
Is there any room to put some three or four pegs circumferentially around the base of the nose cone section? I am on iPad so can't draw them, but thinking pegs on one side and fitted tubes/receptacles on the other. From what you describe, nose not only can't be allowed to sag but also can't be allowed to rotate. Pegs may solve both problems.

That's pretty much what I'm doing except I'm only using one on top and it needs to be external--just too tight inside--I can mold it in and make it look like it's supposed to be there.
 
That's pretty much what I'm doing except I'm only using one on top and it needs to be external--just too tight inside--I can mold it in and make it look like it's supposed to be there.
With one peg ejection might get a bit weird with asymmetric physical (not aerodynamic) drag on nose cone as it slides out. Any chance of molding One peg on each side into the canards? Would slide out balanced.
Also wondering where chute is gonna be? In body or in nose cone? Cone looks big enough to hold it pretty loosely.
 
With one peg ejection might get a bit weird with asymmetric physical (not aerodynamic) drag on nose cone as it slides out. Any chance of molding One peg on each side into the canards? Would slide out balanced.
Also wondering where chute is gonna be? In body or in nose cone? Cone looks big enough to hold it pretty loosely.

Well, I'm still efforting the solution but have not done anything physical to the rocket yet. The canards are mounted too far forward to be of much use. I did consider moving them back and using them by cutting a couple of slots in the rear section and then they would lock in, It's actually the best solution from a couple points of view. first- it's a simple fix, second- it helps with the rockety part if I move them back for stability reasons. But it kills the Dragonfly look with the little canards way up front--that said it is still an option and I keep going back to it.I actually like the look! As far as the recovery gear goes, for the moment the --CHUTES-- are housed mid body. I'm keeping the option open for the next few days to core out part of the nose and move the attachment points forward--that helps with weight distribution a little but it's not needed for that purpose at the moment. I may need that space for larger gear. We'll see in the future!I did come up with one other fix for the problem. I might mount a "finger" under the nose. It would lay against the rear fuselage an support the weight with no effect on ejection. It would have to be a precise fit--I'm not beyond that--over time I suspect it would warp--well still considering that option.I did start laying balsa on the leading edge of the tail and I'll get pics out of that later tonight---H
 
I went ahead and laid up the leading edge of the tail. The first layer was attached with epoxy--20160911_201654.jpg--I used five minute epoxy so I had to work fast. The balsa is 1/16 and plenty flexible.I started at the tip of the tail and worked my way down the curve, holding each area in place with a straight pin. I was careful to not put too much epoxy down. I didn't want to have to sand it off against the foam or the balsa. I put down four layers. I figured that would be enough to sand and get a nice rounded leading edge. Each layer was put down with yellow wood glue and given about a half hour to set before I put the next one down. Again , straight pins were used.--20160913_065153.jpg--I let everything dry for about two hours and the sanded down the sides and shaped it with 220 grit paper---20160913_123433.jpg--pretty good so far, just a little bit more sanding and I can move on---H
 
A little more done. I got the trailing edges on the wing as well as the tail. I also added some under wing root pods. They sort of mimic B-58 gear pods but mainly just give a little detail to the model. Also got the lug placed but it still needs to be centered. I used an aluminum tube that runs from the intake to the rear of the rocket. --20160913_205935.jpg20160914_090925.jpg20160914_090941.jpg20160914_091002.jpg20160914_135143-001.jpg20160914_144943-001.jpg---I really could have gotten a lot more done today but I chose to take a lazy day--H
 
So I've let the old girl sit out in the 100 plus temps for the last few days. The surface temp was more than that I'm sure when it was in the sun. Now I have lots of little bubbles in the surface. THEY ARE UNDER THE PAINT!! Obviously something is out gassing. It could be water or uncured resin. So all that sanding prior to this was for naught. The only reasonable solution to the problem that I can come up with is to poke a pin hole in each one and then put down a layer of FG resin. I need to put some resin over the fillets and balsa anyway. I think the plan is to resin the fillets and balsa first. Once that has set, I can mix up a batch of Hot resin and apply it inside where it's cooler, over the remaining surfaces--the fins do not need it--. The cooler temps should prevent out gassing as the resin sets. That should leave me a hard thin surface to work off of. It should just be a matter of priming and sanding afterwards. Well, that's the thoughts I have. Anybody got any other ideas??--H
 
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