Test to Destruction

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Rich Holmes said:
You know, I thought there was something wonky about those fins (I mean wonkier than they were intended to be) but I couldn't figure it out until now.

THEY'RE UPSIDE DOWN.

I built 'em wrong and installed 'em the same wrong way. The aft end of the root edge is supposed to be the forward end. Hoist by my own petard!

I could slice them off and turn them over but then I'd have a squared leading edge and a rounded trailing edge.

I could slice them off and remake them but then this silly rocket wouldn't get done until around the time NASA puts a crew on Mars.

Or I could adjust my OpenRocket file, delete this post, and pretend I meant to do it that way.
Click to expand...
Adjust the top fins trailing egde to fit the angle of the bottom fin leading edge or make new ones and call it good.
hey,at this point,whats another set of fins.
Or, escape out the back door that doesnt lock..only a few of us know this. I made it out.....I do miss the meds tho.
 
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I meant to do it that way. That is my story and I'm sticking to it.

Last night I sanded the aft fin edges and decided all but one were good. That one got some more Norm.
View attachment 143829
Today I attached the forward fins. First I cut a 1/4" strip of blue tape
View attachment 143830
and wrapped it around the body tube just ahead of the aft fins.
View attachment 143831
That gave me a much more visible alignment for the aft end of the forward fin's root edges than pencil marks on the tube would. The forward fins are too high for the Estes jig, so they were aligned to the aft fins with two popsicle sticks and a clothespin.
View attachment 143832
While I was at it I glued on the launch lug.
View attachment 143833
Here's how Test to Destruction is looking at the moment, wonky fins and all.
View attachment 143834
 
I like the tape alignment trick.
Me eyes can use all the help they can get.
 
Scotty Dog said:
I like the tape alignment trick.
Me eyes can use all the help they can get.
Click to expand...
I know the feeling. That one just sort of came to me and I think it worked out pretty well. Hmm, where are those close-up photos of the alignments of some of my previous fins? Gosh darn, must've deleted them. Can't imagine why I'd do that.
 
Let's put some fin fillets on this puppy. Or maybe on this rocket. Yeah, I'll go with the rocket.

Another (ahem) Test; in the past I've used yellow glue. Here I'm giving Alleen's Tacky Glue a try. I'd use Titebond No-Run No-Drip if I could find any locally, but I can't and I did have the Tacky Glue on hand.
View attachment 143924
I used a popsicle stick to smooth the fillets
View attachment 143925
and a cotton swab to clean up.
View attachment 143926

Hey, look, a launch lug. I filleted that too.
View attachment 143927

This being thickened white glue I probably could have gotten away with doing all fourteen (count 'em, fourteen) fillets at once, but let me save that test for another time. I'm letting these six dry before moving on.
 
Rich Holmes said:
I cut out the fin marking guide. Why doesn't OR give you the launch lug line too? I added that, wrapped the guide around the body tube, and marked the fin and launch lug positions.
Click to expand...

The ends of the OR fin wrap where they meet on the body tube are centered between two of the fins. Voila, launch lug/rail button line. Oh, and I love me some split fins, upside down or not!

https://www.rocketryforum.com/showthread.php?57027-New-upscale-Freefall-XL&p=583552#post583552
 
Someone please explain to me why I wait until after mounting the fins to fill the spirals.
View attachment 144267
Anyway, I do indeed like the normal CWF better than the CWF Max. Goes on less rocky and sands easier. I do need to work on my application technique though. After the first application dried and was sanded I found one spot I needed to touch up, and applied the CWF more cleanly there, so I guess I'm learning.
The body tube join is ugly, especially this part which seems to get only uglier with sanding.I tried stabilizing it with CA, which helped, I think.
View attachment 144268
A couple of dings on the fins were filled with spot filler.
View attachment 144262
Time to work on the nose cone. I sanded down the seams, then roughed up the whole surface.
View attachment 144263
A little blue tape and it fits fairly snugly in a paper towel tube.
View attachment 144264
At this time I probably should have wiped it down with alcohol but I forgot to.
I sprayed it with Rusto Specialty Plastic Primer.
View attachment 144269
After the first coat dried I gave it a light sanding with 400 grit and then sprayed a second coat. I also primed the body, with Rusto Filler Primer, and then sanded with 220 grit... right through the primer in some places.
View attachment 144266
Will definitely need a couple more coats. Someday. Judging from the forecast, probably not tomorrow.
 
I wet sanded the nose cone with 600 grit. As expected the weather is standing in the way of other progress.
 
Some time ago I shot the nose cone with color, but I wasn't happy with the texture of the result. I sanded it down and will try again.

I'd done some more priming on the body, and I sanded it tonight. I would have been tempted to move on to wet sanding, but not after the debacle with the Goony Patriot. It was probably a little too thin in spots. Instead I put another coat of primer on.

Here it is with Patrioony.

View attachment 147144
 
Rich Holmes said:
Some time ago I shot the nose cone with color, but I wasn't happy with the texture of the result. I sanded it down and will try again.

I'd done some more priming on the body, and I sanded it tonight. I would have been tempted to move on to wet sanding, but not after the debacle with the Goony Patriot. It was probably a little too thin in spots. Instead I put another coat of primer on.

Here it is with Patrioony.

View attachment 147144
Click to expand...

Sometime mistakes turn into cool designs.Your rocket looks great to me and the goony is very nice as well.Great job on both builds.:cheers:
 
More acceptable painting weather! And me able to take advantage.
I masked the fins with Scotch Magic Tape, blue tape, and a grocery bag:
View attachment 147636

I shot a little yellow to seal the tape edges, let that dry, and then shot the orange:
View attachment 147633
(I also touched up a problem — an ex-bug, I think — on the nose cone.)

I let that set and then… unmasked. Hey, not bad! A couple not so good spots if you look closely, but I’m happy with it.
View attachment 147634

Here’s the whole thing so far. Once it dries it’ll just need striping tape, decals, clear coating, and a recovery system.
View attachment 147635
 
Time for another test. Of Testors! (See what I did there?)
View attachment 147868

I used the 1/4″ tape for the fin stripes. Using a 13° angle drawn on a piece of paper as a guide I cut the root edges (as it were) and ran each piece from the root of the fore fin to the trailing end of the rear fin. Then trimmed the trailing end and between the fins, and burnished with a Sharpie barrel.
View attachment 147869

I used the 3/8″ tape around the top of the body tube and between fins at the bottom of the tube.
View attachment 147870

Next the decal, which I’d previously printed and sprayed with clear paint.
View attachment 147871

Here it is nearly done.
View attachment 147872
I think the decal’s slightly askew. Probably should have checked it with an aluminum angle or something. Oh well, not expecting perfection, were you?
 
Hey Rich ,that rocket looks really cool......I like that !!!

Nice work :clap:

Regards


Paul T
 
Time for clear coating. I used Pledge Floor Care Finish (it no longer says anything about Future on the label, but this is the stuff) with window cleaner for cleanup.
View attachment 148453

I applied the Pledge with a brush, let the excess drip down, and cleaned the drips up with a cotton swab soaked in glass cleaner. Here’s the result. You can see the clear coat, right? No?
View attachment 148454
Well, it’s there.

The way I set up the Kevlar cord made it difficult (practically impossible as far as I could see) to tie it to the elastic shock cord inside the body tube. (I could have done it before anchoring the Kevlar of course.) So instead I put some tape around the Kevlar at the end of the tube, and reinforced the tube with some CA. Then I tied on a good long piece of 1/4″ braided elastic.
View attachment 148455

I clipped on a 12″ chute, loaded up a B6-4 motor (I don’t have any C motors at the moment) and gave it a swing test, which it passed with flying, um, flying.

So it’s done!
View attachment 148460

I plan on launching it Saturday.
As for the name, “Test to Destruction”: What did I test? What firsts are there here?

  • Design: My first scratch design. (That is, the first scratch design to be designed. Not the first to be built.)
  • Adhesives: This was not the first rocket where I used epoxy for tight-fitting stuff (motor mount and coupler), it’s the second. So that’s fairly new. This is the first where I used Alleene’s Tacky Glue for the fillets. I liked the non runniness and the fillets came out okay, by my standards. But, having given up on finding Titebond No-Drip No-Run locally, I got a bottle from Amazon which I want to try for my next fillets and see which I prefer.
  • Baffle. We’ll see how well it works. I wanted to anchor the Kevlar in a way that didn’t involve adding a screw eye to the build, for some reason, and I messed that up somewhat, resulting in a bulge on the airframe. I’d certainly do it differently next time.
  • Hand cut fins: Aside from not keeping track of which way up they were supposed to go, no problems here.
  • Papered fins: Some of the techniques I used in papering might need rethinking, but they came out okay. I’m not convinced it’s any less effort than filling and sanding, but it does strengthen them.
  • Bondo: If I’d been more careful with the fins I wouldn’t have needed Bondo. But now it’s in my toolkit.
  • Paint techniques: My spray painting abilities have progressed from barely adequate to adequate. I’m getting smoother finishes now, though the yellow is still kind of rough. Maybe that’s the paint. I took some shortcuts with the painting since the last club launch of the season is coming soon and I wasn’t sure how much more painting weather I’d have. Had I built this starting in May I probably would have taken more time and done a little better. This was my first time masking individual fins, and my first time painting a plastic nose cone.
  • Striping: First time using trim tape. Came out well.
  • Decals: First time using homemade decals. Came out pretty good.
  • Clear coat: First time using Pledge. I like it.
On the whole nearly all these experiments turned out better than I expected. Most of them I’ve used again on Patrioony, again with good (arguably even better) results.
 
I think your first scratch built rocket turned out very nicely ,I mean really nice !

It has the cool looking fins ,the snazzy color scheme....very cool.....and the decals turned out great !

Also nice and glossy.

Yessir ,she is a beauty ,you should be proud of that :handshake:


Now for it`s maiden flight ,good luck.

Take care



Paul T
 
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Rich Holmes said:
And I didn't use the ball peen hammer even once!
Click to expand...

After this build ,I would think you can retire the old ball peen hammer ,and substitute a wooden meat mallet ,as I just did to get a fiberglass CR to fit into a nosecone !

Sometimes a hammer(or a rock) is needed in the build !


Paul t
 
At the Syracuse Rocket Club launch today I flew the Test to Destruction on a B4-4, a good flight that ended up about six feet from the one car parked on the field. Nothing damaged, and the baffle protected the parachute just fine without wadding.
View attachment 149227View attachment 149225

[YOUTUBE]_dLgOKzSyRc[/YOUTUBE]

Later on I loaded a C6-5 for a second flight. Moments after it left the pad there was a tremendous roar — I only very briefly thought my rocket had exploded before deciding there was no way it could make such a loud and prolonged noise. Turned out that due to launch director error, a high power rocket had ignited and launched accidentally. No harm done, though; both rockets had good flights. The Test lost the drag race, though.
View attachment 149224View attachment 149226
 

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