Dr. Zooch - Saturn V build - FINISHED

[Mushtang]

Having enjoyed Dr. Zooch's Vostok rocket so much I decided to build my second Saturn V using his kit. The first Saturn V kit I built was the Estes 1/100 scale that currently hangs in my office, never to be flown (unless I build a better one of that scale someday). But this Zooch Saturn V will most certainly be flown, hopefully several times!

The Saturn V has always been my favorite rocket, even before getting into this hobby. I've read volumes on it and have visited the left over pieces that used to lay on their side outside at the Huntsville Space Center several times. I don't know why it took me so long to get into building these.

I ordered this kit (and a Freedom 7) a couple of months ago from the Ant and it's been sitting on a shelf taunting me, daring me to get started, but I needed to get a few other things finished first. But I finally opened the box, ate the free yogurt, and got started on the build after a brief few days in the hospital.

Before starting this build I searched and found multiple build threads for this kit on these forums, but I've had so much fun with previous build threads that I wanted to do another anyway. I hope that nobody minds if I add one more to the list. I promise to use lots of pictures since that's what I like to see in build threads. As always, feel free to comment, give advice, heckle, point out my mistakes, and share your experiences with this kit.


(This is not my box, this is an image I found online)

 

[Boosterdude]

I enjoyed building mine, and it flies great.

Take your time, and enjoy building the Saturn V.

 

[Mushtang]

The first step, as always, is to take the parts out of the box and look them over to see if anything is missing. Everything looked good to me and I even managed to take a picture of the parts in focus this time.



The card stock sheet that came with the kit with all the printing on it was curled badly from being in the body tube for so long, so that needed some attention to get it to be flat (flatter).

I scanned the card stock and the decals so that I could print them again later if I screw up on something and need to make another one. The decal sheet looks good, and a second sheet with the decals printed on paper was also in the box. I'm not sure if this was included so I could reproduce the decals easier if needed or not. Maybe it'll get mentioned in the instructions. Or perhaps there was only one kit with this extra paper included, and when the Ant reads this he'll tell me I've won a major award!!! Oh, happy day!!!

 

[hcmbanjo]

This is my favorite of the Zooch kits, I'm looking forward to the build!

 

[Mushtang]

This is my favorite of the Zooch kits, I'm looking forward to the build!

I looked at your blog to see if you'd built one but you didn't document it there. Is there a thread of yours somewhere I couldn't find? I'd love to stea... um, get some ideas.

 

[Mushtang]

The motor mount was a very typical motor mount with laser cut centering rings (that had to be wiped off to keep black ash from all over my hands), an engine block, and a motor clip that mounts through the wall of the motor tube.

One thing that I did differently from the instructions, just for the hell of it, was to add a piece of card stock under the motor clip as it penetrated the tube. This was to strengthen the body tube for the pressure of the clip during ejection. This WAS in the instructions on other kits but the Ant probably knew that it wasn't needed here. I figured that it couldn't hurt, except for maybe the small amount of weight that would throw off the center of gravity and cause the rocket to be so unstable that it spirals around before crashing into a small child, so I did it anyway - just to be safe.



When all that was done I added some glue fillets to the centering rings.



These were smoothed around with my finger and allowed to dry. Several more were added to make sure there was a strong bond. Unfortunately this also added more weight. I've read that the center of gravity on this model is very sensitive and I'm probably ruining the rocket before I get off of step 2. Dang it.

 

[NJRick]

Great choice!! this will be a great build thread to follow. I built the Zooch Saturn 5 over the winter...I have only had a chance to fly her once...flew perfectly. Ya know....the Skylab Saturn 5 is a cool kit too!

 

[Mushtang]

The engine block had to be glued into the motor tube but not flush with the end like some models do. This one is required to be glued all the way against the metal clip that sticks through the tube, giving the motor more to push against.

Here is the block, and the motor tube it's about to mate with. They were a bit shy at first, but a little sandpaper livened up the party.



If the motor is pushing on one side of the clip, and the engine block is on the other side of the clip, the motor really only pushes against the clip, and not the block. So I cut a small notch into the engine block so it would fit over the piece of clip and the motor would press against the clip AND the engine block.

Unfortunately for some reason I don't have a picture of this even though I'm pretty sure I took one. So you'll have to use your imagination.

Getting the engine block in place with glue on it required that I put the glue on the inside of the tube first, and then slide the engine block down to meet it. If I had put glue on the engine block and then tried to slide it down into place I would have wiped most of the glue off by the time it got there - if it got there at all. A greater risk is the glue setting up with the tight fit and the engine block being glued permanently in place only halfway to where it was supposed to be. There are other options of course, such as using slow setting epoxy, but no matter what was put on the block it would get wiped off pushing it down the tube. The best way, for me, is to put the glue inside the tube first, then slide the block into place. This also has the benefit of not having to go buy a package of slow setting epoxy!

Luckily the glue bottle I use was long enough for me to be able to put the glue on directly without having to place it in the tube a drop at a time. I get to do that later to glue the centering rings into the body tube. Here's me putting the glue into the motor tube.



Once that was in I inserted the engine block, notch first and lined up with the clip and started pushing it down with my finger. The block rotated because I was pushing on one side and was heading down the wrong way. I pulled it out of the tube and grabbed a motor to use for pushing instead. This was a lot better and I soon had the engine block in place.



When I took the motor out it had a lot of glue on the end of it. I wiped it off quickly but now I'm a little paranoid about ever using it. I hope that there's not a tiny bit of dried glue that will melt someday from the heat of a launch, and then dry again, gluing the motor inside a rocket. :y:

 

[Mushtang]

So far the posts to this build thread have been pretty boring, and none of the build has really been Saturn V specific. All rockets have motor mounts and they're all very similar. The posts that are specific to this kit will be a lot more fun to read.

Here's another post that's not.

The instructions then say to glue the motor mount assembly into the bottom of the main body tube. Once again I decide to put glue on the inside of the tube instead of onto the ring. I cut a stick from some old balsa fin scraps and placed a pencil mark where the depth of the glue needed to be. The mark is the distance from the inside surface of the tube where the glue will go, to the opposite edge of the tube, not the edge directly above the glue. That's because when putting the glue in it's a lot easier to put it in with the balsa stick angled.



Once a circle of glue is placed in the tube for the upper centering ring the motor mount assembly is put in about halfway. At this point glue is put onto the outside edge of the lower centering ring and the assembly is shoved into place.



The instructions have the lower centering ring mounted flush with the bottom of the tube so there's a limit to how much additional glue can be added for strength. I put on one more layer once the original glue had dried and it still looks okay. When I first shoved the assembly into place I looked in the top of the tube and saw that the excess glue on the top centering ring was pushed up and formed a fillet there, so I'm satisfied it's going to be strong enough.

 

[Mushtang]

Finally, some Saturn V parts!!

The instructions have you dry fit all the tubes and balsa transitions together at this point and paint them white. A lot of this will be covered up with paper wraps but since plenty will be showing I decided that I'd like to fill the seams and sand the transitions.

There are two balsa transitions, one that goes between the 2nd stage and the 3rd stage, and another at the top of the 3rd stage that is the LM reduction and the CM. Only the top balsa piece will be visible, the other one is completely covered by a wrap. Unfortunately I didn't realize this and painted Carpenters Wood Fill on both pieces. No worries, that's just a little bit of added weight. What could go wrong?



I sanded them both smooth anyway just to reduce the weight on one and make the other one pretty. Looking closely at the piece after I sanded it it's not super smooth yet so I could have done another round of CWF and sanding, but the two applications of primer will certainly cover up anything remaining. The CWF was more to fill in the deeper grain.

Each end of the middle balsa reduction and the bottom of the top balsa piece had shoulders that fit into tubes, but when dry fitting them they were a SUPER tight fit! So I spent a few minutes sanding around and around and eventually they were able to go together a lot better. There's nothing wrong with a snug fit, but I couldn't even get these in without sanding.

The tubes then had their seams filled with CWF. Since there are wraps that go around large sections of these tubes it would have been okay to measure them out and only fill the seams on the parts that would be visible, but it's fairly easy to do so I went ahead and filled the entire seam from one end of the tube to the other. I used Chris Michielssen's suggested 1:4 mix of water to CWF and used a hobby knife to fill the seams, about 2 inches at a time. First I apply the CWF to the seam using the sharp edge, then I pat it in place using the flat side of the blade.



By the time I was finished applying the CWF to the second tube the first one was dry and ready to be sanded. When I finished it the second one was dry and sanded.



In past builds I've masked about 1/8" to either side of the seam and shot some primer on them to hold the CWF in place. I recently read that this was more for larger body tubes and not really necessary for these smaller tubes. So I put the pieces together for the next step of spraying all of them with primer.



It doesn't quite look like a Saturn V yet, but it's definitely heading in that direction!

 

[JPVegh]

op:

NEAT!

 

[Blakkzakk]

I'm currently building a Dr. Zooch Saturn V, myself. I didn't take any pics....sorry.

I'll post pics of the finished product.

 

[Mushtang]

Primer time!

EDIT **** If you're following this thread while building one of these, read posts 38 and 40 before spraying with primer. You might want to mask off the CM section of the upper balsa piece and not spray primer or paint on that section (but you do want to spray the LM reduction area). You might also not want to spray any primer or paint on the lower balsa piece in the middle of the rocket. I ended up sanding most of it back off in order to get the wraps to fit. ****

The main BT, reducer balsa, secondary tube, and nose balsa were dry fitted together and placed on a dowel for coating with primer. The dowel was small enough to go through the engine block and because the pieces weren't glued together the dowel would push the balsa reducer out. So I used some blue painters tape to wrap around the motor clip and the short section of the motor tube. This held the tube high enough on the dowel, and protected the clip and motor tube from getting sprayed.

Then I went to my paint booth (unfinished basement) and gave it a good coat of primer.



After letting it dry overnight I sanded it with 220 grit paper which removed quite a bit of the primer but left the tube and balsa pieces very smooth.



I then took it back and gave it another coat of primer.



The next painting step is to cover it with white, which I plan on doing with at least 2 coats.

Unfortunately after letting it dry overnight the weather around here turned rainy and has been that way for the last couple of days - and I refuse to paint when it's raining outside. Since I've started that policy I have reduced my paint wrinkles and crackles by quite a lot!

But there are several things I'm able to do before the white paint goes on, so I can keep going.

 

[Mushtang]

I'm currently building a Dr. Zooch Saturn V, myself. I didn't take any pics....sorry.

I'll post pics of the finished product.

Yes, please do!! How are your engine bells turning out? I haven't started mine yet and I'm a little scared of them.

 

[Blakkzakk]

Yes, please do!! How are your engine bells turning out? I haven't started mine yet and I'm a little scared of them.

I haven't got to that point, yet. I'm probably going to give it one final coat of paint today.

I'm using Krylon semi-gloss white for two reasons, one, even though they were painted flat white IRL, they all seemed to shine in the sun and two, so the decals will stick better.

 

[Mushtang]

While waiting for good weather to paint I decided I can skip ahead to the engine fairings.

These look like they'll be really neat, and I'm impressed with the Ant for coming up with this method for creating them! As a mechanical engineer things like this are the most impressive parts of these kits - way more impressive than sanding something so much that the finish looks like plastic. I'm impressed with the clever ways that the designers come up with to do things.

For those that haven't seen these before, the card stock sheet has 4 of these printed fairings that look like this:



I didn't bother asking the Ant for his permission to post an image of his work, but I figured that since it was out of focus and I included the copyright notice, he wouldn't object.

The instructions say to cut these out and glue them on a tube the size of the motor mount tube. Once the glue dries you cut them out of the tube and they're the right shape and size to glue onto the main body tube right above where the engine bells will go. Very cool! After that you're supposed to cut out the center section (the yellow area labled "Cut Out") and this exposes the cardboard for gluing the fin to. The cardboard is a better surface for gluing than the printed paper.

Thinking ahead I decided that it might be better to cut out the Cut Out before gluing, and that would make it easier to get to the cardboard below. It seems like cutting it out after it's glued on will only make a mess. If I didn't think this through enough I might be causing myself more problems, but I have nobody to blame but... um... I blame Luke Strawwalker. He's not here to defend himself. Luke, if this doesn't work, you should have told me not to do this!!!!

So my first step is to cut out all the Cut Outs. Here's the first one on it's way.



I cut the sides of them using a metal straight edge and then carefully cut the bottom and top. It didn't take long to get all four out.





Now that I have all of the Cut Outs cut out I can move along to cutting out the fairings.

 

[Mushtang]

I haven't got to that point, yet. I'm probably going to give it one final coat of paint today.

I'm using Krylon semi-gloss white for two reasons, one, even though they were painted flat white IRL, they all seemed to shine in the sun and two, so the decals will stick better.

Yes, always put decals over gloss paint. You can go over it with a flat clear coat later if you want, but if decals are put on anything other than gloss then they'll look funny.

After I put the decals on my Estes 1/100 Saturn V I covered it with flat clear coat and it looks great.

 

[Mushtang]

After cutting out the Cut Outs I used a straight edge and hobby knife to cut the sides of the fairings, and then cut the curve with scissors. Holding one of these against the small tube and trying to wrap it showed me why cutting out the Cut Outs first might have been a bad idea. Damn you Luke!! With the big section in the middle missing it was easy to accidentally fold the fairing instead of wrapping it.

But being the steely eyed whatever that I am, I was able to move past this problem without problem. My workspace is the kitchen table, and on this table sits a napkin holder filled with paper napkins. We have good table manners at our house as we eat dinner among the rocket parts. So I grabbed half the stack and laid it down in front of me and put a fairing on top of it - upside down. Then I reached into my bag of tricks and pulled out a small dowel that I used to curl some of the card stock during my Vostok build.



Using the dowel I rolled it across the back of the fairing lightly, and then as it started to curl I pressed harder. After rolling the dowel over the fairings for a few minutes it was curled just right, and without a single crease or fold! Here I am rolling a fairing.



I'd like to point out that the phrase "rolling a fairing" sounds a lot worse than it is. Anyone still giggling at this point is free to leave. It didn't take very long to roll all 4 fairings and now they're ready to be put on my small tube.

:no:

 

[Mushtang]

To get the fairings into the correct shape they need to be glued onto the tube fairly straight. I'm sure there's probably a little bit of forgiveness if the fairing is glued on slightly crooked but I wanted to avoid that as much as possible. So to help me I decided to draw 4 lines down the tube and use those to line up the fairings. Using my 3 sided engineers ruler I drew 4 lines approximately 90 degrees to each other.



The opening left after I cut out the Cut Out would help line up the fairing on the pencil line. Here's one that is dry fit on the tube.



I laid a fairing on it's front and put a few drops of white glue on the back, and then spread it around with my finger to make sure I covered every bit of the paper in a thin layer of glue. Being careful to wipe off my finger before picking up the fairing, I turned it over carefully and lined it up with a pencil line.

To get it to stick really well I wanted to press down on the fairing, but that would squish the tube, so I grabbed another dowel and slid it in the tube and I used that to roll the tube and fairing against the cutting board. This made it easy to press the paper firmly to the tube. If you do this, roll it slowly, not fast like you would roll dough with a rolling pin, but very slowly putting pressure down on the dowel. If you go too fast you'll risk screwing up the fairing if a corner should come lose. Nobody ask me how I know that, it's done and forgotten.



But seriously, roll it slowly.

That's how I got all 4 fairings glued to the tube where they now await being cut out.



I think I'll leave them intact for now and wait on weather to be good for painting the rocket white first. I don't want the curve in the cardboard to relax any.

 

[Mushtang]

Still can't paint the rocket white, but found more stuff to do.

The shroud that goes over the balsa reduction between the 2nd and 3rd stage gets cut out and glued into a reduction shape. In previous builds I've not had a lot of luck with shrouds fitting. I was given the suggestion that on Dr Zooch kits I should cut exactly down the middle of the black line (as opposed to staying to the outside or inside) so this it what I did. I'd made a scan of the sheet in case I messed up, and I believe the Ant has an offer to send replacement sheets if they're messed up too. With the confidence built up knowing that failure was not an option, I proceeded to carefully cut the shroud out with my trusty scissors.



That's one good looking shroud!

The next step is to get it curled in preparation for gluing the tab to the other side. I did this the same way I curled the fairings, using my stack of napkins and a dowel rod.



The key to rolling something curved, like the shroud, is to always keep one end of the dowel pointed to the center of the circle, so that the dowel is always parallel to the lines on the side of the shroud. If you just roll it straight back and forth, the paper will curl in a goofy direction that won't make a good shape for the reduction.

In this picture I'm rolling near the end of the shroud, but I've kept the dowel turned to point to the middle.



After a few passes of pressing lightly, I give it a few more pressing harder, and this curls it as much as can be expected. The next step is to pick it up and curl the shroud into a cone shape a little tighter than the final will be glued, making sure to keep the top and bottom lined up correctly, and with this in my closed hands I breathed slowly into the cone to let moisture from my breath penetrate the paper. This helped the paper keep the correct shape, plus might have aided me in the next step when I was fitting it to the balsa reducer.

 

[Mushtang]

I'd followed all the directions, cut the shroud exactly on the lines, and was sure that it would fit when I put it on the balsa. So I wrapped it around and when the edges came together... it didn't fit.

The ends did overlap a little, the glue tab was under the end of the shroud, but the edges of the printed parts just wouldn't come together the right way. So I moved it around, pulled, pushed, breathed more moist air on it, pulled, pushed, checked the line of the bottom edge against the balsa lip, pushed, pulled, and somehow it eventually fit. I was holding on tightly to that shroud knowing that it might not easily go back to that position if I let go. So I allowed the ends of the paper up so I could put some glue on the tab, and then pressed it back into place.

I used very little glue since it doesn't take much to glue paper to paper. And I didn't want any getting squished out the back resulting in the shroud being glued to the balsa too soon. After giving it a few firm presses of the thumb directly on the glued area, I took the shroud off and let it finish drying on the table.



A little later I put it back on the balsa and tube so see how it fit again.

Like a glove!



Unfortunately I DID make a mistake, and when I was pressing on the glued area right when I put the glue on, a tiny bit of glue did come out the front, and I smeared it across the black area before I realized it. So here is blemish number 1.



I suppose I could print another shroud from the scan and try again, and maybe I will, but for now I'm okay to just leave it. So I took the shroud back off and set it on the table.

The good news is that the forecast calls for no rain for a couple of days, so I might attempt to paint the rocket white tonight when I get home. Hooray!!

 

[luke strawwalker]

Looking really good so far! KUTGW!!

I usually use white glue for the motor mount in the tube, because yellow glue shrinks quite a bit and tends to "suck in" the wall of the tube around the ring, leaving a low spot visible on the outside of the tube where the ring mates to it on the inside. (Even using a lot of white glue can cause this too, so one needs to be careful of putting too heavy of a fillet inside in the tube around the centering ring to body tube joint-- ask me how I know this... LOL) Anyway, the "glue on a stick at the correct depth" is the best way to put the glue in the tube for the upper centering ring... I usually insert the motor mount halfway at this point and then apply a quick bead of glue inside the end of the tube before inserting the motor mount the rest of the way into the tube, to glue the lower centering ring up as well as possible. Sometimes I'll carefully drip some white glue down inside the tube to the tube wall/centering ring joint and "fillet" it with a stick... just for insurance... I usually fillet the aft centering ring to the rear lightly with a finger and then spread the extra glue across the face of the centering ring to the motor tube, just to spread the excess glue out, and also seal the aft face of the rear centering ring... this helps it resist heat and gunk from "base plume recirculation" (hot gases from the motor that circulate back up into the vacuum at the rocket's base in flight and stain/scorch the aft end of the rocket) plus this also gives a tougher surface and joint for gluing on the nozzles later on...

Later and good work!
OL JR

 

[luke strawwalker]

I'd followed all the directions, cut the shroud exactly on the lines, and was sure that it would fit when I put it on the balsa. So I wrapped it around and when the edges came together... it didn't fit.

The ends did overlap a little, the glue tab was under the end of the shroud, but the edges of the printed parts just wouldn't come together the right way. So I moved it around, pulled, pushed, breathed more moist air on it, pulled, pushed, checked the line of the bottom edge against the balsa lip, pushed, pulled, and somehow it eventually fit. I was holding on tightly to that shroud knowing that it might not easily go back to that position if I let go. So I allowed the ends of the paper up so I could put some glue on the tab, and then pressed it back into place.

I used very little glue since it doesn't take much to glue paper to paper. And I didn't want any getting squished out the back resulting in the shroud being glued to the balsa too soon. After giving it a few firm presses of the thumb directly on the glued area, I took the shroud off and let it finish drying on the table.

View attachment 79422

A little later I put it back on the balsa and tube so see how it fit again.

Like a glove!

View attachment 79423

Unfortunately I DID make a mistake, and when I was pressing on the glued area right when I put the glue on, a tiny bit of glue did come out the front, and I smeared it across the black area before I realized it. So here is blemish number 1.

View attachment 79424

I suppose I could print another shroud from the scan and try again, and maybe I will, but for now I'm okay to just leave it. So I took the shroud back off and set it on the table.

The good news is that the forecast calls for no rain for a couple of days, so I might attempt to paint the rocket white tonight when I get home. Hooray!!

I've had this happen some too... hard not to get glue residue or fingerprints on the wraps sometimes...

Here's a trick I've found that often works...

Take your X-acto hobby knife and gently SCRAPE the offending glue crud away... it doesn't take much, usually, just a few light strokes with the blade held 90 degrees to the direction of the scraping stroke with VERY light pressure... you don't want to cut, just drag the edge of the knife across the stained area... hold the knife so the blade is straight up from the surface, 90 degrees to the surface, not tilted either into or away from the direction of the stroke. A few light passes will usually remove any glue stains and restore the appearance of the spot... but be careful... if you go too far or do too much, it will make the paper "fuzzy", and/or remove the printed on details... usually with careful knife control it's not a problem... the printing should be under the glue mess, and if you're careful you can scrape up to the lines and remove the glue crud without scraping the lines themselves... scraping glue crud off the black printed sections is the hardest, because you don't want to take off any of the printed on black surface which would change it's appearance... and the black ink is "on the surface" and soaked into upper layers of the paper itself... usually I end up with an occassional "ugly glue fingerprint" on the black that sticks out terribly and is just fugly-- but usually a couple quick scraped with a hobby knife cleans it up very nicely...

Good luck! OL JR

 

[luke strawwalker]

The first step, as always, is to take the parts out of the box and look them over to see if anything is missing. Everything looked good to me and I even managed to take a picture of the parts in focus this time.

View attachment 79040

The card stock sheet that came with the kit with all the printing on it was curled badly from being in the body tube for so long, so that needed some attention to get it to be flat (flatter).

I scanned the card stock and the decals so that I could print them again later if I screw up on something and need to make another one. The decal sheet looks good, and a second sheet with the decals printed on paper was also in the box. I'm not sure if this was included so I could reproduce the decals easier if needed or not. Maybe it'll get mentioned in the instructions. Or perhaps there was only one kit with this extra paper included, and when the Ant reads this he'll tell me I've won a major award!!! Oh, happy day!!!

Word of advice to/from the peanut gallery--- I remove the instructions and wrap sheets from every one of my Dr. Zooch kits as I get them and store them in a large manila envelope so that they get a chance to relax and 'lay flat' for a long time before I build the kits... usually they're rolled up lengthwise inside a tube, which is a neat way to ship them, but it's a PITA when you go to build the kit and the wrap sheet stays rolled up like a newspaper and won't lay flat, and even worse when the wraps are curled "the wrong way" 90 degrees from the direction they need to curl to go onto the tube...

Storing flat REALLY helps... but make sure you can find them again! LOL

Later! OL JR

 

[luke strawwalker]

The engine block had to be glued into the motor tube but not flush with the end like some models do. This one is required to be glued all the way against the metal clip that sticks through the tube, giving the motor more to push against.

Here is the block, and the motor tube it's about to mate with. They were a bit shy at first, but a little sandpaper livened up the party.

View attachment 79197

If the motor is pushing on one side of the clip, and the engine block is on the other side of the clip, the motor really only pushes against the clip, and not the block. So I cut a small notch into the engine block so it would fit over the piece of clip and the motor would press against the clip AND the engine block.

Unfortunately for some reason I don't have a picture of this even though I'm pretty sure I took one. So you'll have to use your imagination.

Getting the engine block in place with glue on it required that I put the glue on the inside of the tube first, and then slide the engine block down to meet it. If I had put glue on the engine block and then tried to slide it down into place I would have wiped most of the glue off by the time it got there - if it got there at all. A greater risk is the glue setting up with the tight fit and the engine block being glued permanently in place only halfway to where it was supposed to be. There are other options of course, such as using slow setting epoxy, but no matter what was put on the block it would get wiped off pushing it down the tube. The best way, for me, is to put the glue inside the tube first, then slide the block into place. This also has the benefit of not having to go buy a package of slow setting epoxy!

Luckily the glue bottle I use was long enough for me to be able to put the glue on directly without having to place it in the tube a drop at a time. I get to do that later to glue the centering rings into the body tube. Here's me putting the glue into the motor tube.

View attachment 79198

Once that was in I inserted the engine block, notch first and lined up with the clip and started pushing it down with my finger. The block rotated because I was pushing on one side and was heading down the wrong way. I pulled it out of the tube and grabbed a motor to use for pushing instead. This was a lot better and I soon had the engine block in place.

View attachment 79199

When I took the motor out it had a lot of glue on the end of it. I wiped it off quickly but now I'm a little paranoid about ever using it. I hope that there's not a tiny bit of dried glue that will melt someday from the heat of a launch, and then dry again, gluing the motor inside a rocket. :y:

Spent motor casings are great for doing this... makes it really easy to push the thing down without risking a usable motor... plus you can always cut an extra ring(s) off the end of the spent motor casing if you need them using your razor saw...

So long as you cleaned the motor up thoroughly, it should be fine...

Later! OL JR

 

[luke strawwalker]

Primer time!

The main BT, reducer balsa, secondary tube, and nose balsa were dry fitted together and placed on a dowel for coating with primer. The dowel was small enough to go through the engine block and because the pieces weren't glued together the dowel would push the balsa reducer out. So I used some blue painters tape to wrap around the motor clip and the short section of the motor tube. This held the tube high enough on the dowel, and protected the clip and motor tube from getting sprayed.

Then I went to my paint booth (unfinished basement) and gave it a good coat of primer.

View attachment 79219

After letting it dry overnight I sanded it with 220 grit paper which removed quite a bit of the primer but left the tube and balsa pieces very smooth.

View attachment 79220

I then took it back and gave it another coat of primer.

View attachment 79221

The next painting step is to cover it with white, which I plan on doing with at least 2 coats.

Unfortunately after letting it dry overnight the weather around here turned rainy and has been that way for the last couple of days - and I refuse to paint when it's raining outside. Since I've started that policy I have reduced my paint wrinkles and crackles by quite a lot!

But there are several things I'm able to do before the white paint goes on, so I can keep going.

Best painting stick is take the dowel, and glue an old motor casing over the end of it... doesn't matter that the nozzle goes in first... I actually built up an old curtain rod with blue painters tape and shoved a spent motor casing over it, and the motor mount is inserted over this spent casing for spraying the rocket... plus it holds it while it dries...

For "D" motor rockets, a spent "D" motor casing will slide right over a spent 18mm casing once it's cleaned out of motor gunk...

Later! OL JR

 

[luke strawwalker]

While waiting for good weather to paint I decided I can skip ahead to the engine fairings.

These look like they'll be really neat, and I'm impressed with the Ant for coming up with this method for creating them! As a mechanical engineer things like this are the most impressive parts of these kits - way more impressive than sanding something so much that the finish looks like plastic. I'm impressed with the clever ways that the designers come up with to do things.

For those that haven't seen these before, the card stock sheet has 4 of these printed fairings that look like this:

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I didn't bother asking the Ant for his permission to post an image of his work, but I figured that since it was out of focus and I included the copyright notice, he wouldn't object.

The instructions say to cut these out and glue them on a tube the size of the motor mount tube. Once the glue dries you cut them out of the tube and they're the right shape and size to glue onto the main body tube right above where the engine bells will go. Very cool! After that you're supposed to cut out the center section (the yellow area labled "Cut Out") and this exposes the cardboard for gluing the fin to. The cardboard is a better surface for gluing than the printed paper.

Thinking ahead I decided that it might be better to cut out the Cut Out before gluing, and that would make it easier to get to the cardboard below. It seems like cutting it out after it's glued on will only make a mess. If I didn't think this through enough I might be causing myself more problems, but I have nobody to blame but... um... I blame Luke Strawwalker. He's not here to defend himself. Luke, if this doesn't work, you should have told me not to do this!!!!

So my first step is to cut out all the Cut Outs. Here's the first one on it's way.

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I cut the sides of them using a metal straight edge and then carefully cut the bottom and top. It didn't take long to get all four out.

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Now that I have all of the Cut Outs cut out I can move along to cutting out the fairings.

That should work... I did it after it was all glued up, but your way might work better actually because it's kinda hard to do afterwards...

Of course you may have to trim them up a bit depending on the size and shape of your fins when they're ready to go on... it all depends... the actual Saturn V fins were a wedge shape for 50% of their length (roughly) and the rest rectangular in cross-section. That's "more or less" how I did mine... if you want to see a pic of the actual cross-section of the fin, go to John Pursley's "accur8.com" website and he's got tons of Saturn data on there, including the fairings and fins and stuff like that...

Good luck! OL JR

 

[luke strawwalker]

After cutting out the Cut Outs I used a straight edge and hobby knife to cut the sides of the fairings, and then cut the curve with scissors. Holding one of these against the small tube and trying to wrap it showed me why cutting out the Cut Outs first might have been a bad idea. Damn you Luke!! With the big section in the middle missing it was easy to accidentally fold the fairing instead of wrapping it.

But being the steely eyed whatever that I am, I was able to move past this problem without problem. My workspace is the kitchen table, and on this table sits a napkin holder filled with paper napkins. We have good table manners at our house as we eat dinner among the rocket parts. So I grabbed half the stack and laid it down in front of me and put a fairing on top of it - upside down. Then I reached into my bag of tricks and pulled out a small dowel that I used to curl some of the card stock during my Vostok build.

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Using the dowel I rolled it across the back of the fairing lightly, and then as it started to curl I pressed harder. After rolling the dowel over the fairings for a few minutes it was curled just right, and without a single crease or fold! Here I am rolling a fairing.

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I'd like to point out that the phrase "rolling a fairing" sounds a lot worse than it is. Anyone still giggling at this point is free to leave. It didn't take very long to roll all 4 fairings and now they're ready to be put on my small tube.

:no:

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Glad that worked out...

Why you blaming me?? I didn't tell you to do that! LOL Hey it's worth a shot and worked out well, so it's all good... just another one of those things that experience is the best teacher though... despite the difficulties in rolling the fairings with the centers cut out, this is still a neat technique... cutting them afterwards means that basically, to cut them away, you're cutting into the tube wall beneath them (however slightly, depending on how carefully and lightly you cut!) to remove them later on... and that's not a good thing either since the "cut through" weakens the conical bit of tube underneath them to which the fin is glued... so it's six one way half dozen the other I guess...

I used this same technique (paper fairing glued to a tube) for my BT-80 Saturn V that I'm slowly but surely working on... Thing is, the actual Saturn V fairing is a HALF CONE, and taking the section out of the tube wall leaves a curved surface where the fairing glues to the outside of the main body tube. At this small size, it's not a big deal, but on anything bigger, you have to "coax" the tube section edges straight and tighten the curvature near the tip of the fairing to get it to lay down properly on the tube... not an issue with the Zooch Saturn V, but if you adopt this technique on a larger build, it's one of those "gotchas" to be aware of... fortunately "coaxing" the fairing into the proper shape isn't bad with the use of a mechanical pencil to press the tip of the fairing around to tighten it's point and a sharpie marker barrel to press and work the sides of the fairing around to tighten their curvature as well into a half-cone...

Next time I might try making cones from cardstock and then bisecting them vertically into a pair of fairings... (cutting the cone in half vertically).

Later and KUTGW! OL JR

 

[Mushtang]

Oh hey Luke. Um... welcome back! Heh. Gee, the comment I made about you in post 16 was just a joke, I swear. Um.. yeah. Just a joke.

 

[hcmbanjo]

A little later I put it back on the balsa and tube so see how it fit again.
Like a glove!

View attachment 79423
QUOTE]

I remember thinking how thick the shoulder was with the printed wrap over the adapter.
But, it'll match up perfectly with the wrap that goes around the top of the main body.