Dr. Zooch - Saturn V build - FINISHED

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Mushtang

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While the fins were drying I started on the numbers that go on the side of the rocket. First I cut them out of the decal sheet and set them aside.

82 numbers cut.jpg

Of course, by "decal sheet" I mean, "instruction sheet". They're just paper, but this works great for this model! :D

The numbers, I, II, III, and IIII are glued to the side of the model, on the left edge of every black section near the bottom. I wanted them all to be at a uniform height so I made a guide from the card stock sheet. There was no specific height given so I eyeballed it and cut a notch that I would used to set the numbers on top of. Then I poured a small puddle of white glue on a scrap piece of card stock, dipped the back into the glue with tweezers, and placed it on the rocket using the height guide I made.

83 height guide.jpg

After a few minutes all the numbers were on the rocket at the same height all the way around. Hooray!

84 numbers glued.jpg
 

hcmbanjo

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Wes, another idea. Please consider making a YouTube video of you making some FGP for the nozzle of an F-1 engine bell. I think seeing it done by the creator would be a LOT better for some people than reading about it. There are a lot of people on these forums that have said they failed to be able to make it. What do you think? And if you could snap it up... I'm almost to that step. :lol:
Hi Mushtang -
This is a great build thread!
I thought I did a thread on the Zooch Saturn V but never did.

I ended up using some of that 2 part Epoxy clay that Apogee sells to make the FGP nozzle pieces.
At first I didn't have any luck making FGP with Elmer's white glue. (I use white glue for the bulk of my builds because it dries clear)
But I've since tried making FGP with yellow Titebond and the results were much better. It doesn't take a very large "pea" shaped piece to make the nozzle pieces.
 

Mushtang

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Hi Mushtang -
This is a great build thread!
I thought I did a thread on the Zooch Saturn V but never did.

I ended up using some of that 2 part Epoxy clay that Apogee sells to make the FGP nozzle pieces.
At first I didn't have any luck making FGP with Elmer's white glue. (I use white glue for the bulk of my builds because it dries clear)
But I've since tried making FGP with yellow Titebond and the results were much better. It doesn't take a very large "pea" shaped piece to make the nozzle pieces.
Thanks! This is definitely one of my favorite builds that I've done so far. These Zooch kits are great, and I'm looking forward to building the Freedom 7 after I finish this one.

I'll give the FGP a try with white glue and then if that doesn't work I'll try it with the yellow wood glue. If that fails I'll get some of the stuff that Luke used. It just makes me nervous after reading about so many people trying to make it and failing, I have yet to read about someone successfully making some with white glue other than the Ant himself.
 

Mushtang

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Now that the fins were dry, and the numbers on the rocket were drying, I could put the letters on each side of the fins. These are also printed on the instruction page with two each of the letters A B C and D, one for each side of a fin.

The instructions show a diagram of a letter on a fin but it's not dimensioned, so I got to just eyeball it. I sat a fin down and without any glue I put a letter A on it to see where it would look best. Because I wanted all the letters to be in the same place on each side of each fin, I needed to make a guide similar to the one I used for the numbers. To do this I used a fin I cut from the Fin Marking Guide and positioned a letter on it roughly in the same place I had decided it would look best on the fin.

85 letters dry fit.jpg

Then I marked the location with a pencil and cut out a notch to use. I could lay this on the side of the fin and using tweezers lay a letter in the corner and they'd all be in the same place. To do the other side I only had to flip the guide over.

86 letter guide cut.jpg

I then used the guide and placed all 8 letters. Holding a letter with the tweezers I ran the back across the small puddle of white glue, then wiped off the excess with a finger, and placed the letter into the corner of the guide.

87 letter guide used.jpg

After they were all glued in place I took this picture of the fins and went to bed.

88 letters drying.jpg

This morning as I'm posting this, the picture makes it look like a couple of the letters aren't on straight and the guide was never used. I'm 98% sure this is just the camera angle and the way the fins aren't parallel to each other or perpendicular to the camera, but I'll be sure and double check this when I get home.
 

Dr.Zooch

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That template for placing the fin letters is a GREAT idea! I'm gonna use it myself the next time I do Saturn V fins.
 

Mushtang

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That template for placing the fin letters is a GREAT idea! I'm gonna use it myself the next time I do Saturn V fins.
Thanks. I wish I could take credit for it, but it's not my idea.

It was something the instructions on the Centuri kit had that I saw Hcmbanjo use in his blog here:
http://modelrocketbuilding.blogspot.com/2011/06/estes-saturn-v-build-part-66-decals_10.html

I remembered having done that back when I built my Estes Saturn V and following his blog to do it, so it was easy to make a good one to use out of your fin cut out.

Someday I want someone to point to an idea that I did actually come up with and say they're going to use it themselves. In the mean time I'll keep using everyone else's good ideas. :)
 

ksm2001

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Great build thread along with good pictures Mushtang. Very nice job in building. I was thinking of building this Saturn V to fly also some time down the road since my Estes one will go on display when finished. I'll definatly use your thread when I get to the build point.

Ken
 

Mushtang

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The paint and letters on the fins dried overnight and they were ready to be glued onto the rocket. The Cut Out area on the fairings wasn't quite large enough for the fins to be able to touch the tube below so I had to use my hobby knife and cut some of the card stock away at the leading edge. A few minutes with each fairing and I was ready to glue on the fins.

First I sanded, once more, the root edge of the fins. A little of the metal paint had dripped down here or there and I wanted to make sure it was just balsa that the glue was grabbing.

Next I ran a small bead of glue along the root edge , spread it with my finger, and touched it to the fairing where the fin would go to get some glue on the tube too. Then I sat the fin down and did the next one the same way. This, of course, is the double glue method, and it works very well. Here are my fins with the glue drying:

89 Double Glue for Fins.jpg

Each fairing was labeled on the inside of the Cut Out with a letter so I'd be SURE and glue on the right one. I could have figured it out by looking at the numbers around the side of the rocket, but I didn't want to make a mistake so I wrote the letter to be clear. Here is one fairing after getting hit with the first glue. You can see the letter A as well as the glue that was left behind from touching the fin to it.

90 Double Glue for fins.jpg

While waiting for the glue to dry I went ahead and glued up the engine bell halves. That'll be the next post.

After about 10 minutes of gluing bells, I was able to put on the fins. I applied another small bead of glue to the root edge of a fin, over the glue that was nearly dry at this point, and then held it in place on the fairing. It doesn't take long for the fin to really grab tight with this method. Here is the rocket after 3 fins have been glued on. You can also clearly see the paper on the bottom is in the wrong position. This is bothering me more and more every time I see it, so I'll definitely print a new one before gluing on the engines.

91 gluing fins.jpg

Now all the fins are on and the rocket looks good from the top view.

92 all fins on.jpg

When the glue dries I'll give it a fillet or two of glue along the edges to give it a little extra strength.
 

luke strawwalker

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hey Mushtang and Luke...thank you for your tips...especially regarding the smudge...I am currently working on Dr. Zooch's SA-203 Saturn 1b....and I got a smudge of steel paint, tiny as can be...on a rolled white lox tank....RATS! :bang:
but thanks to your thread Mushtang and your input Luke..I tried the razor blade and son of a gun if it didn't gently remove that smudge....I mean...it couldn't have stuck out any worse..:eyepop:..right dead smack in the middle of a white tank..I must have gotten it on my finger without even knowing it...was a tiny spot...but stood out like a sore thumb and it was the kinda spot that I was afraid anything I tried to do to fix it would only compound the mistake.......but not any more!! thank you!!!! you guys are both steely eyed missile men
Glad I could help and thanks for the compliment... "you're a steely-eyed missile man" was about the biggest compliment you could get back in the Apollo days! :D

Great build Mushtang... every one is a learning experience... sorry about your tape travails and off-center engine base heat shield... Like you said, fairly easy to fix... I thought I'd TOTALLY screwed up on the Friendship 7 when I realized I had painted it with gloss white instead of flat white and had to re-tape the whole thing... and taping over those external engine fairings and feedlines and cable trays and stuff is a pretty good amount of work... but I jumped in and redid it and it turned out great! SO, be persistent and take your time... really THINK about everything your doing beforehand and it should turn out well. Sorta like playing chess-- sometimes you have to be thinking several steps ahead... when you don't, you end up with goofs-- like me gluing the launch lugs on the "front" of the EFT-1 instead of the "back"...

One other thing to watch on your fins for the Saturn V-- make sure that the bottom edges are "parallel" to the "ground"... IE they should be flat and not "swept back" like I've seen some end up... them being mounted on a slanted surface (of the fairing) complicates this but the Saturn V just doesn't look right with "swept fins".... :)

Later and KUTGW! OL JR :)
PS... that's strange that the tape did that... usually Tamiya tape is about the Cadillac of tapes... gentle adhesive, won't "wick under" it, conforms well, etc... I noticed you're using half-inch tape... I picked up some 1/8 or 3/16 wide Tamiya tape at the hobby shop... I outline stuff with that to establish the actual paint line, and go over that with the cheap(er) blue stuff to cover areas or tape down drop paper or plastic bagging over large areas that I don't want oversprayed... Works well... the thinner tape is easier to apply and work with as well... and Tamiya tape burnishes well into the tiniest of corners without leaking paint! GREAT stuff... One tip that might help for next time-- always pull tape back over itself at a steep angle-- almost flat back onto itself... this generates the least "lifting force" when removing the tape to hopefully prevent taking the paint (or paper wrap) with it...
 
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Mushtang

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One other thing to watch on your fins for the Saturn V-- make sure that the bottom edges are "parallel" to the "ground"... IE they should be flat and not "swept back" like I've seen some end up... them being mounted on a slanted surface (of the fairing) complicates this but the Saturn V just doesn't look right with "swept fins".... :)

Later and KUTGW! OL JR :)
I've already noticed that mine are indeed swept back a bit. I think it's a result of the fairings not standing up as high as they should?? Maybe I didn't glue them in the correct place?

At first I wanted to try and sand them level, but the Ant has been very clear that the size of the fins is important to the flight being correct, so I didn't want to remove any area. I guess this build won't be nearly as close to the intended design as others have been, but that's okay. I'm learning.

As long as it flies okay and looks good from 10 feet away, I'll be happy!!
 

Mushtang

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While waiting for the glue to dry on the first application of the double glue method, I got to work gluing the engine bell halves together. There are 5 sets given in the kit and the instructions say to build all 5 even though you only need 4. But as we've seen, I'm not very smart about these things, and I just glued 4 together even though I glued all 5 sets into cones.

The main reason is that while looking over the parts I found one cone of each half that wasn't glued straight. It was able to eliminate them, leaving me with 4 sets that were similar.

The top cones overlapped the bottom section more than I expected them to, so if I were to go back and do these again I'd cut the top sections inside the lines on that bottom edge instead of right on the lines.

To glue them I poured a puddle of glue onto a piece of cardboard and dipped the top half into it, getting plenty of glue on the bottom edge.

93 gluing engine bells.jpg

Then I fit a bottom section into the top and used my finger to push the glue up under the lip. This seemed to get plenty of glue in between the halves and I let them dry.

94 drying engine bells.jpg

After the glue dried I put another small bead of glue around each bell right on the seam, and again pushed the glue up into the lip with my finger.

I'm not too worried about these being wrong - I think they're good. According to the instructions the FGP will cover the seam. Plus, the rest of the work that is done to these engines makes them look really great and people looking at the engines will be too impressed to notice anything that doesn't line up exactly.
 

Mushtang

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The instructions next have you wrap the engine bells with the supplied string to simulate the look and then you create some Funky Glue Putty (FGP) to mold around the bells to emulate the exhaust manifolds.

I looked in my kit for the string and only found the parachute string, and the parts list on the first page didn't identify any string other than the parachute string either. Having confused myself completely I emailed Wes asking him if that was the correct string to use or was I missing my supply of engine bell string. (He replied today letting me know that the parachute string WAS the correct stuff to use on the engine bells, and there would be plenty left over for the parachute)

So with nothing immediate to do I decided to have a try at making some FGP. I retrieved a bottle of yellow glue from the garage and attempted it with this stuff:

95 yellow glue.jpg

The first thing I did was to put a couple of big drops on my finger and start rolling it around with my thumb. But the glue doesn't roll around, it spreads. I quickly had glue covering my finger and thumb and moving them together didn't do a whole lot. However I kept at it because my understanding was that as the glue dried it would be more putty like and less runny. Blowing across my finger and thumb helped it dry some as I kept moving them in circles, making the glue mess bigger. After a few minutes of this I was about ready to stop and just then the glue started to change. There were sections that had dried enough to be slightly solid instead of liquid, so I pressed my finger and thumb together harder to create more friction and that helped peel the dried glue from my skin. Very promising. After another 5 minutes I had formed all the glue into a small ball that looked and felt a lot like putty. It was the size of a small BB and not nearly enough to form a shape like is shown on the instructions page, but I could now understand better how to make this stuff.

I needed more glue to make enough for an engine, so instead of using finger and thumb I switched to palm and finger. A quarter sized puddle, or maybe a little larger, puddle of yellow glue was poured into my left palm, and using my right index finger I started stirring the glue and spreading it out. It took a little longer than the first attempt, but eventually it dried enough to become putty like. So I tried to roll it into the shape that the directions show and this is what I got:

96 first attempt at FGP.jpg

It's not as pliable as putty, when I tried to roll it out or form a specific shape it wouldn't go. Maybe I let it get too dry before trying to shape it?? I'll probably do a few more of these before I get to the point of needing them for the engine bells and I'll try and get better at it. Maybe if I figure out exactly how it works I'LL make a video and post it on YouTube about how it's made.

Are there other Dr. Zooch kits that require FGP to build?
 

Mushtang

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The final thing I did on the kit last night was to add a fillet of glue to the fins for a little extra strength. I'll probably do another one or two as I'm finishing up.

97 fin fillets.jpg
 

luke strawwalker

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I've already noticed that mine are indeed swept back a bit. I think it's a result of the fairings not standing up as high as they should?? Maybe I didn't glue them in the correct place?

At first I wanted to try and sand them level, but the Ant has been very clear that the size of the fins is important to the flight being correct, so I didn't want to remove any area. I guess this build won't be nearly as close to the intended design as others have been, but that's okay. I'm learning.

As long as it flies okay and looks good from 10 feet away, I'll be happy!!
Yeah I've seen a number of them that way... There can be some variance in how much you "curve" the point of the fairing that determines how it mates up to the main body tube when they're glued on, which can change the angles a bit, which is of course magnified by the fins when they're glued on to the tapered fairings... The only way to really ensure that this doesn't happen is to custom fit the fins to the fairings, test fitting everything beforehand, and sanding the root edge a tiny bit at the front or rear end of the root edge to correct any "sweep" so the fin's trailing edge is 90 degrees to the main body tube... well, within reason and accuracy of the Mark 1 eyeball anyway... doesn't have to be PERFECT...

You're right though-- you don't want to cut the fins down much at all doing this, because the fins are sized as close to scale as possible and still keep this rocket stable with the existing amount of noseweight...

Later! OL JR :)
 

Mushtang

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Yeah I've seen a number of them that way... There can be some variance in how much you "curve" the point of the fairing that determines how it mates up to the main body tube when they're glued on, which can change the angles a bit, which is of course magnified by the fins when they're glued on to the tapered fairings... The only way to really ensure that this doesn't happen is to custom fit the fins to the fairings, test fitting everything beforehand, and sanding the root edge a tiny bit at the front or rear end of the root edge to correct any "sweep" so the fin's trailing edge is 90 degrees to the main body tube... well, within reason and accuracy of the Mark 1 eyeball anyway... doesn't have to be PERFECT...

You're right though-- you don't want to cut the fins down much at all doing this, because the fins are sized as close to scale as possible and still keep this rocket stable with the existing amount of noseweight...

Later! OL JR :)
I love how you pointed out, in post 69, that I needed to be careful to avoid putting the fins on wrong... which I'd done in post 68.

:cry:

Why couldn't that post have been here a day sooner?!

:D :cheers:
 

Mushtang

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Work on the engine bells continues. The remaining steps before having to deal with the FGP are to wrap the engine bells with string and to wrap some small dowels with paper. And I mean small!

The string for wrapping the bells is the parachute string supplied with the kit. You're told to cut 4 pieces to a specific length and glue one end to the seam of the bells where the two halves meet. Like this:

98 string glued.jpg

It takes a few minutes for the glue to set up enough so the string doesn't pull off while trying to wrap it, so I went ahead and glued all 4 to dry at the same time.

99 strings glued.jpg

Wrapping these strings is fairly straightforward, but it took me a few tries to get a method that worked well. First I just wrapped one as is and tried to glue it down when I finished. But that just resulted in the string moving all over the bell and bunching up as I tried to glue it. So I pulled that one off and tried something else that also didn't work.

Eventually I figured out that it was better to let this get a little messy. Glue wipes off fingers pretty easily when you're done. What worked for me was to put a few lines of glue all the way around the bell before I started wrapping, so that the string would be wrapped into the glue, and my fingers would be spreading the glue on the bell as I turned it round and round while wrapping. There's really no way to avoid your fingers spreading the glue, but that's okay since that's what you want. So it starts off like this:

100 glue on bell.jpg

If you click on the picture you can see about how much glue I put on to start with, and this was done all the way around. About 5 lines I think.
 

Mushtang

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Once the glue is on the bell just slowly wrap the string around the lower section of the bell, keeping the distance (about a 1/16") between each wrap as uniform as you can. When I got finished with the first one it looked like this:

101 wrapped in glue.jpg

So I sat it down and repeated the process on the other three. I think they turned out really well.

102 4 bells wrapped.jpg

After the glue dried I followed the directions again and put a thin layer of CA on the string to really hold it in place. This was a lot easier to do using the cone shaped end of a large dowel to hold it.

103 CA spread on string.jpg

While they dried, I decided to have another crack at making some FGP.
 

Mushtang

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Funky Glue Putty - Test Two

This test of FGP creation worked better than the first but I think I used too much. I poured some in the palm of my hand as before, and slowly started stirring it.

7:11 pm
104 FPG 01.jpg

105 FGP 02.jpg

I'm not sure if the stirring makes any difference or not but that's what I did. I also would lift my finger out of the puddle a lot to try and let more dry. I think the quickest way to get it to start forming is to spread it out more.

7:16 pm
106 FGP 03.jpg

I kept moving the glue around and it started to thicken up.

107 FGP 04.jpg

And a few minutes after that the stuff changed into a big sticky mess. This was about the consistency of cookie dough, sticking to everything but not nearly as tasty.

7:18 pm
108 FGP 05.jpg

With my finger I was able to pull all the glue up from my hand and roll it into a small worm shape. Eight minutes from pour to finished.
 
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Mushtang

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I took the roll of FGP and placed it on the instruction sheet image that showed how big the roll needed to be. You can see where I've pulled off a lot of the FGP to try and get it to the correct size and shape, but I think it's still too big.

109 FGP rolled.jpg

To check, I rolled it around one of the engine bells and it's definitely too big.

110 FGP on bell.jpg

However, I'm now confident that I'll be able to make the FGP for the engine bells per the instructions.

One important thing I've learned about FGP is that there is a very short amount of time where it can be formed into whatever shape you want. After that is over the putty is still fairly soft and pliable, but it won't easily hold a new shape. It tends to snap back.

For instance, the image in the instructions show a bulge in the middle of the worm shape. In the stuff I just made I was able to form that bulge easy during the short time where it's able to be formed. But I realized the time had passed when I tried to roll out the thinner ends and reduce their diameter. Whenever I tried to press and roll them they'd return to that size when I let go. The key must be starting off with the correct amount of glue and using all of it - that way you form the right size worm shape to begin with.

What do you think Dr. Zooch? Am I doing this correctly?
 

luke strawwalker

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I love how you pointed out, in post 69, that I needed to be careful to avoid putting the fins on wrong... which I'd done in post 68.

:cry:

Why couldn't that post have been here a day sooner?!

:D :cheers:
Sorry... maybe when I have a better computer I can get on here more...

Later! OL JR :)
 

luke strawwalker

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Work on the engine bells continues. The remaining steps before having to deal with the FGP are to wrap the engine bells with string and to wrap some small dowels with paper. And I mean small!

The string for wrapping the bells is the parachute string supplied with the kit. You're told to cut 4 pieces to a specific length and glue one end to the seam of the bells where the two halves meet. Like this:

View attachment 80262

It takes a few minutes for the glue to set up enough so the string doesn't pull off while trying to wrap it, so I went ahead and glued all 4 to dry at the same time.

View attachment 80263

Wrapping these strings is fairly straightforward, but it took me a few tries to get a method that worked well. First I just wrapped one as is and tried to glue it down when I finished. But that just resulted in the string moving all over the bell and bunching up as I tried to glue it. So I pulled that one off and tried something else that also didn't work.

Eventually I figured out that it was better to let this get a little messy. Glue wipes off fingers pretty easily when you're done. What worked for me was to put a few lines of glue all the way around the bell before I started wrapping, so that the string would be wrapped into the glue, and my fingers would be spreading the glue on the bell as I turned it round and round while wrapping. There's really no way to avoid your fingers spreading the glue, but that's okay since that's what you want. So it starts off like this:

View attachment 80264

If you click on the picture you can see about how much glue I put on to start with, and this was done all the way around. About 5 lines I think.
I find the easiest way to do those is to put the engine bell over the end of a sharpie marker and use that as a holding tool, and turn the nozzle to wind the thread around it...

Glue the thread to the nozzle at the midpoint as instructed, let that dry... (sometimes clamping it with a smooth-jawed hemostat helps keep it in place and aligned properly til the glue sets up good... then pop the hemostat off). You're absolutely right-- you have to glue the thread end to the nozzle first or the stuff will just slip n slide and never really want to wind around the nozzle in a predictable way.

Once dry, put the nozzle on the sharpie marker and apply a drizzle of glue to the nozzle surface, then, rolling the pen between your fingers and keeping the string taut, gently roll the thread onto the nozzle in a gentle incline, keeping the coils about 3/32 inch (a little over 1/16) apart. The last coil should be about 1/16 or so from the bottom edge of the nozzle. Clamping this down when done usually helps, since the end will want to "pop up" due to the stiffness of the "poly-coated Popeilium" string the Doc uses in his kits... if you don't have any smooth-jawed hemostats or narrowed down clothespins, pinching it for a bit while the glue tacks up is usually sufficient...

Turn the nozzle on the pen a few times and coax the wraps of string up or down as needed to ensure they're all evenly spaced and straight... a toothpick works well for this...

Once this first layer of glue has tacked up and is nearly dry, put another drizzle of white glue on the nozzle all the way around over the thread, and then using a fingertip, rub that into/over the thread and wipe off the excess... this will "lock" the thread into place and ensure that it doesn't break loose or anything later on... you just need a thin layer of glue-- it won't hide the detailing but adds a lot of strength, because basically the glue "fillets" the string to the nozzle...

Set aside to dry. Presto gorgeous nozzles...

Good work!

OL JR :)
 

luke strawwalker

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I took the roll of FGP and placed it on the instruction sheet image that showed how big the roll needed to be. You can see where I've pulled off a lot of the FGP to try and get it to the correct size and shape, but I think it's still too big.

View attachment 80276

To check, I rolled it around one of the engine bells and it's definitely too big.

View attachment 80277

However, I'm now confident that I'll be able to make the FGP for the engine bells per the instructions.

One important thing I've learned about FGP is that there is a very short amount of time where it can be formed into whatever shape you want. After that is over the putty is still fairly soft and pliable, but it won't easily hold a new shape. It tends to snap back.

For instance, the image in the instructions show a bulge in the middle of the worm shape. In the stuff I just made I was able to form that bulge easy during the short time where it's able to be formed. But I realized the time had passed when I tried to roll out the thinner ends and reduce their diameter. Whenever I tried to press and roll them they'd return to that size when I let go. The key must be starting off with the correct amount of glue and using all of it - that way you form the right size worm shape to begin with.

What do you think Dr. Zooch? Am I doing this correctly?
Great work! Glad someone finally explained that in a way that makes sense!

Sure looks messy though... but hey, if it works... :)

Personally I don't regret using the epoxy putty, even though I handled it bare handed, which you really shouldn't do... what was nice about it was, I could carve it to shape after I installed it on the nozzle and it dried... amazing what a little trimming and scraping with a sharp hobby knife could do... gently rounded them out and got them to the exact shape I wanted...

I think this one is too big (I made some too big too which is why I carved them down carefully) but do they shrink as the glue dries?? How well do they bond to the nozzle?? Did you try gently carving it with the hobby knife??

Great work... thanks!

OL JR :)
 

Mushtang

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I think this one is too big (I made some too big too which is why I carved them down carefully) but do they shrink as the glue dries?? How well do they bond to the nozzle?? Did you try gently carving it with the hobby knife??
I knew this one was too big before I put it on the bell and looking at the picture it's most definitely too big. They do shrink some when drying but I still think that might have been too big. I didn't keep it on the bell, I removed it right after the picture was made and set it aside. Tonight I'll put it back on and see how it would look dried.

Maybe it'll surprise me and will have shrunk to the correct size.

I didn't try to carve it but I don't think it would carve nearly as easily as actual putty. I'd rather roll one that will shrink to the right size, put it on, and be done with it.
 

Mushtang

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On the real engine there is a large pipe leading down the back side that splits and curves around the bell which is an exhaust manifold. On the model the FGP is used to form the manifold but small dowels are used for the large pipe.

Several of these small diameter dowels are included in the kit for the detailing on the sides of the rocket, and I'm supposed to cut 4 pieces that are 3/8" long??? I'm 43 years old and even wearing glasses I can barely see a piece that small. :D But somehow I managed to cut 4 of them to the right length.

111 cutting dowels.jpg

Then I cut 4 pieces of paper from the instructions that looked like this:

112 paper to roll.jpg

These are to be wrapped around the end of the dowel with the decreasing width of the paper leaving a spiral around the upper section to emulate part of the engine.

The only way I was able to do this was to wind the paper around the dowel without glue, then while holding the paper in place put a drop of white glue somewhere on the paper. After that I slowly turned the dowel and paper in my hand so that my fingers would spread the glue all over the paper in the direction it was wrapped. After doing this the paper stayed in place, and after the glue dried it was finished.

113 roll with glue.jpg

It really doesn't take long, and soon I had all 4 completed.

114 4 dowels ready.jpg
 

luke strawwalker

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I knew this one was too big before I put it on the bell and looking at the picture it's most definitely too big. They do shrink some when drying but I still think that might have been too big. I didn't keep it on the bell, I removed it right after the picture was made and set it aside. Tonight I'll put it back on and see how it would look dried.

Maybe it'll surprise me and will have shrunk to the correct size.

I didn't try to carve it but I don't think it would carve nearly as easily as actual putty. I'd rather roll one that will shrink to the right size, put it on, and be done with it.
That was the nice thing about the epoxy putty... (think it was "miracle putty" or whatever I bought at Walmart... think that really annoying guy used to advertise it on TV, or it was a clone product). I could make the thing and attach it to the nozzle, and then I carved them down a bit to size once I was done... worked great...

Thought they might break loose and fall off and I'd either have to glue it back on with white glue (if it came off in one peice) or make new ones (if they crumbled) but not a one of them broke loose, and I carved the "small side" on them pretty thin, so that was pretty impressive stuff to me...

Glad you got the FGP to work though... You're a steely eyed missile man now! :)

Later! OL JR :)
 

luke strawwalker

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On the real engine there is a large pipe leading down the back side that splits and curves around the bell which is an exhaust manifold. On the model the FGP is used to form the manifold but small dowels are used for the large pipe.

Several of these small diameter dowels are included in the kit for the detailing on the sides of the rocket, and I'm supposed to cut 4 pieces that are 3/8" long??? I'm 43 years old and even wearing glasses I can barely see a piece that small. :D But somehow I managed to cut 4 of them to the right length.

View attachment 80288

Then I cut 4 pieces of paper from the instructions that looked like this:

View attachment 80289

These are to be wrapped around the end of the dowel with the decreasing width of the paper leaving a spiral around the upper section to emulate part of the engine.

The only way I was able to do this was to wind the paper around the dowel without glue, then while holding the paper in place put a drop of white glue somewhere on the paper. After that I slowly turned the dowel and paper in my hand so that my fingers would spread the glue all over the paper in the direction it was wrapped. After doing this the paper stayed in place, and after the glue dried it was finished.

View attachment 80290

It really doesn't take long, and soon I had all 4 completed.

View attachment 80291
Nice turbine exhaust ducts and heat exchangers... the conical heat exchanger duct you just made preheated the gas generator fuel, which then went into the combustor to produce the hot gases that drove the turbopumps... the hot gases then passed through the turbine wheel and out through the heat exchanger, cooled slightly in preheating the fuel, and then down into the 'semi-conch' shaped exhaust duct surrounding the nozzle extension... if you've never seen a real F-1 up close, this duct dumped the "cooler" (only around 1700-2000 degrees or thereabouts) turbine exhaust gas through passages into the nozzle extension of the F-1, which is the huge lower, less conical nozzle portion below the duct. Above this was the smaller, steeper sided engine nozzle itself which was made of thousands of small tubes brazed together to make up the nozzle wall and combustion chamber... through which kerosene was pumped to cool the walls and prevent the engine from melting down. The nozzle extension was protected from the 5,000 degree engine exhaust from the main nozzle by a thin layer of "cooler" turbine exhaust gas from the conch-shell shaped duct... the nozzle extension interior has thousands of approximately 2 x 4 inch "shingles" with gaps around them, which allowed the gas to bleed through and protect them from the extremely hot engine exhaust coming from the nozzle itself.

That's why when you look at videos of the Saturn V taking off, the F-1 engines appear to have "dark" gases pouring out of the nozzles for several feet behind the nozzles, which then breaks up into blindingly bright exhaust fire that seems to be "chasing" the engine... once free of the nozzle, the flow of "cool" exhaust gas from the nozzle extension would continue to flow straight and smooth for a few feet before starting to break up in turbulence behind the engine... this actually 'enshrouded' the blindingly bright and hot engine exhaust in "dark" cool turbine exhaust, until the turbulence broke up the layer of turbine exhaust into the main brilliant exhaust plume, which then turned blindingly bright, appearing to "chase" the engine...

I always wondered why that appeared that way until someone on NSF explained it to me... then it made perfect sense! Just a bit of trivia I thought I'd share...

Later and KUTGW!! OL JR :)
 

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Now that I had the method for making FGP down I made some for the first bell.

115 one FGP bell.jpg

It turned out okay, maybe a little big still but I'm happy with it. A short time later I'd done them all.

116 all bells with FGP.jpg

A day later I took another picture as the FGP had dried out some and shrunk a little bit.

117 FGP a day later.jpg

They're not perfect but I think they're an acceptable first attempt.

Does anyone know of any other Dr. Zooch kits that require FGP?
 

Mushtang

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Before painting the dried engine bells I wanted to prep all the small wooden pieces that go on the outside of the rocket.

The first are the pieces of balsa cut from scraps of the fin sheet that will become the S-IVB APMs and the S-IVB ullage motors. The APM is, I think, the Attached Pressurized Module (according to Google) but I have no idea what it does on the real Saturn V. I do remember that the ullage motors thrust the rocket forward to settle the propellants in the rear of their tanks so that the engines can be started and be able to suck liquid instead of gas.

Mine started off like this:
118 small balsa bits.jpg

And after a few minutes with an emery board they look like this:
119 shaped balsa bits.jpg

That seems about right.
 

Mushtang

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As Luke Strawwalker pointed out earlier, the bottoms of my fins weren't horizontal, they were angled backwards. They're supposed to be horizontal, but I guess the way I glued the fairings onto the body tube made them not stand up like they should have. After he pointed it out I noticed it every time I looked at the model so I had to fix it!! Could you live with this?

120 Fins pointed down.jpg

The first thing I did was to pull off each fin. To get a fin off I slowly bent it back and forth until the glue weakened and eventually let go. When they came off there was a lot of dried glue that had to be cut off and the surface cleaned up. Here's one fairing that just lost a fin:

121 fins broken off.jpg

After that I sanded the root surface of each fin to remove a *slight* amount of wood, giving the fin a different angle at the fairing connection. The outside edges of the fins actually stick out at least the same distance if not a little further, so I hope this removal of fin area doesn't make it fly badly. But the fins went back on and the bottoms are now horizontal. Hooray!

122 fins sanded and glued back horizontal.jpg
 

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WOW - you sure do build some kits :)

Those engine bells look scary :y:

Hats off to you on this one - waaaaaaay beyond my ability for sure.
 
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