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gary7

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All park activities in my local area in Illinois have been cancelled through the summer. That most likely includes our local big annual event, "GARLO". I've been diligently working to have rockets ready for it and it's a big let down for me. I may try to fly what I can alone somewhere with just a few family members anyway as long as I don't break a waiver or rules by flying a rocket or a motor that requires FAA waiver. That most likely will include this rocket I have been posting here. It exceeds the weight limit for high power rockets without a waiver. Without paint (construction is done except for finish work) it is at 3.7 pounds now. So disappointing.

I will continue to build however and post the progress here.

And keep my proverbial fingers crossed.
 
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gary7

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The construction is done. Dreading the finishing tho.

Based on the standard formulas for ejection charges (see Mark Canepa’s book on high power rocketry or Vern Knowles web site) the calculated charge was about 0.9 grams. I used 1 gram and it was, well see for yourself.

 

gary7

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Took 10 days off to visit family members in Atlanta and Orlando areas. Of course I drove so spent almost 1/3 of my time driving. Tiring. But got back to business on this project yesterday .

I have not been totally satisfied with the polyethylene hoop at the aft end so I decided to try this. I mentioned it earlier, turning a ring. The first pic here shows my son doing the initial rounding. I got a very nice piece of 7 ply, 3/8 plywood at Woodcraft. It was big enough to make two attempts at this. And it was only about $13 including shipping! We did it in only one try!
 

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gary7

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Here are the poly and plywood rings side by side:
ring comparison.jpg

The one on the right is the poly. As you can see, it isn't exactly round although it appears to be so on the rocket. It also appears slightly larger in this picture.
But:
ring compar 2.jpg Stacked, they are almost identical in diameter. Both snap right into place on those fierce looking fins.

wood ring on.jpg This pic shows the wooden one in place. It still needs some sanding but it has advantages. Or does it?
 

gary7

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Polyethylene has an issue with paint. I found some acrylic spray primer that is supposed to work. I would follow that with the enamel color I have chosen. I have good success with 2X Rustoleum.

The wood on the other hand, covers easily with any primer. I use Dupli-Color filler primer on this kind of project. Works great! And the Rustoleum adheres to it to make a very nice finish.

This rocket will weigh about 3.5# so weight difference of the two rings is negligible . The poly is ~1.4 oz. The plywood is ~1.7 oz.

On the pad, no one will probably see the slightly out of round poly hoop. Even up close, it still may not be that noticeable.

My dilemma? Which to use.
The poly will have some "spring" or "recoil" if it (the hoop) hits the ground. The plywood will not. I am using a chute that should bring it down at about 20 fps. I just don't have the room for anything larger with better descent rate than that. Whether or not that makes any difference. However, I believe it does.

I have considered just snapping either into place as opposed to epoxying them into place so that if they do move and hit the ground just wrong, they will not jolt the entire thing too hard.

Any opinions about which to use? If so, please state your reasons including any science to back up any claims or said opinions.

Probably will not work on it today other than this posting here today. My wife got called back to work (got furloughed and she works in health care!) starting tomorrow so I'll be alone to get some things done without her. Maybe some of you understand that. But don't get me wrong here. She is very good to me and a wonderful person!
 
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markjos

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Nice job on the wood ring, Gary! It's a tough call - which to use, I think. On one hand, as you say, the poly ring has some "give" to it, but will probably not keep its paint - especially when it flexes. The wood one is likely more fragile (well, not *fragile*, but not flexible), but definitely will take paint well. Hmm. I've got nothing scientific for you. I also like the idea of just barely tacking the ring in place, and letting it come loose if it hits hard. I'd hate to see it destroy the fins.

Just my $0.02. I can't wait to see this fly
 
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neil_w

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I dunno what the right answer is but that wood ring is a thing of beauty.

I do like the idea of not gluing the ring in, if you can get it to set really securely.
 

gary7

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I dunno what the right answer is but that wood ring is a thing of beauty.

Thank you!

It's been a while and yes, I am still working on this thing.

But, the ring or hoop or whatever, does have flaws. It is a tiny bit warped but I may be able to fix that. And it has some scratches and tear out from the turning as seen here:

IMG_0837.JPG

Nothing a little Bondo couldn't fix.
 

gary7

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I was also a little off (actually, alot off) on my hoop notches on the fins:

Nothing a little epoxy clay won't fill here.
 

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gary7

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The old Loc nose cone was a bit warped. I suppose sitting in a non-environmentally controlled ware house for over 10 years might do that???
That warp showed badly when I made the nose cone section (see earlier posts). I was able to get it pretty well smoothed out, again with the Bondo.
 

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gary7

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A problem I discovered on two of the main fins. I can certainly see that after cutting and epoxying them on, two of them warped as you may see in this photo.

Look along the edge of the fin you see in the middle here. Idk about any of you, but this kind of thing drives me crazy. I doubt that it will effect flight much. Or will it? They really were straight when I put them on.
 

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gary7

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Tomorrow is a very busy day. My #6 daughter is getting married. Am I allowed to say I'd rather be working on this rocket?
NO!
He really is a very nice guy and I like him just fine.

Back next week.
 

gary7

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Daughters all in town for a very small wedding (covid : / ) and father's day.

Adria n Jordan.jpg



My Mrs. is off Thursday and we always spend time together those days.

Doubt I'll get much done this week. But I am getting closer to priming. I would almost be willing to pay someone to do that for me. This is going to be one difficult paint job to do.
 

gary7

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Time to get back to work on this project.

Have Been trying something new: external mini fin fillets to permit easier painting inbetween here:

71EED33E-BF90-4CE1-91FD-F7E2C7D62985.jpeg
The fins and body tube will be different colors. That is one reason why I wanted mini fillets. This small space is another reason.

But I’m using wood glue. Uhh a mistake. Very difficult to make them smooth.

Have decided to do what I can and leave it. And as someone once told me, “No one is going to notice it while on the pad”.
 
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gary7

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Another issue came up with this today:

66658718-F9A7-43E8-86DD-43319D35EA7A.jpeg

I like to use thin CA on the ends of paper tubes (in this case, Loc) but forgot to do that. Now have to do so while trying to keep it from dripping all over the airframe. No, it will not come off from where it is. Although not glued on yet The fins are here on this end and the forward larger section of airframe is forward of here. Maybe a piece of parchment paper will help?
 

gary7

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Yet another small issue.
No idea just how I did this. Probably while trying to round the trailing edge some.

47E86621-0E97-406B-BEE1-44741BAD6458.jpeg
See it??

Nothing again a little Bondo won’t fix.
 

gary7

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For anyone wondering or who cares:

2C55DC14-57DF-4821-A2E8-A8942E48F7CD.jpeg
Works great on lots of small scratches like this.
 

gary7

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I was going to fill this with foam but even tho it isn’t visible unless looking almost directly at the aft end, it might add something aesthetically. Especially to this rocket!

631E2C42-8BCC-4261-A109-0EFA11337510.jpeg

That MMT is very secure with one forward CR , one aft CR, 8 fins holding it on the aft end and four of those (main) fins with TTW construction.

Purple tape is there to protect where my
retainer will be JB welded on.
 

gary7

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You can see that fin scar filled with the Bondo coming thru in this pic.

3AB7201E-462A-4317-8C3C-6A601C6ED892.jpeg

All is needed is a 30 minute drying time to sand. I usually give it 45.
 

mbeels

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Looking good, that fin scar will totally dissapear.

I like to use thin CA on the ends of paper tubes (in this case, Loc) but forgot to do that. Now have to do so while trying to keep it from dripping all over the airframe. No, it will not come off from where it is. Although not glued on yet The fins are here on this end and the forward larger section of airframe is forward of here. Maybe a piece of parchment paper will help?
I would just drip a little on the ends, and let it run where it runs. Sanding and priming will cover up any runs of the thin CA.
 

gary7

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Well, the ring/hoop or whatever it is to be called, isn't as straight as I thought.

 

gary7

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Looking good, that fin scar will totally disappear.

I would just drip a little on the ends, and let it run where it runs. Sanding and priming will cover up any runs of the thin CA.
I think it (the scar) has after just once sanding.
Dripping the CA was exactly my plan and exactly what I did. Few drips easily removed. Just used a micro applicator and took my time.
 

gary7

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Got the Aero Pack retainer on yesterday. I think it will add somewhat to the appearance of the overall design of this rocket in particular.

IMG_1079.jpgIMG_1080.jpg
 
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gary7

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Finally got my pen light so that I can actually see inside my smaller diameter rockets now. I really like this thing.

61522230714__B3DEB575-E412-40E0-AE3E-2617E8A52D78.JPG lighted Tesla tube.jpg

You can see the light going into the left side. It has a flexible arm and a pocket clip that will clip on Loc tubes. Again, this is a 54 mm Loc motor tube. I could hardly see in there before. Now I can see the three struts on the Giant Leap Hard Point shock cord anchor and the quick link. Anxious to try getting that crow foot socket down in there and try changing cords.
 

gary7

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So I had some problems. The wrench fits inside the airframe and I could get it on the quick link but it kept slipping off. Maybe a bit smaller size but I am sure I tried it before I put it in there. Must have tried getting it off for an hour. But we all know the definition of insanity...

Will just leave it. For now.
 
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gary7

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And now to start my favorite part of this project (yeah, right).

prime time.JPG 2 coats prime.jpg

What a difference just a little primer makes in the way a rocket looks!
 
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gary7

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Taking another break so no work on this for three days.

This was about 6:15 am while on a walk in the country near Litchfield, IL.

6BA1E386-197A-44AF-8A09-7A50F39321CA.jpeg
 

gary7

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Back to work on this yesterday. Real painting now.
It's not as shiny and pristine as I hoped but it works. Rather than risk making it worse, I will just leave it as it is, especially when one compares it to how it was! Yeah, I'm settling but...


2IMG_0695.jpg painted nose cone.jpg

Will do some airframe painting today as well. Anyone who has painted any rockets with more complex surface "interference" like this one, you know it will take time. Allowing paint to dry 24-48 hours before taping off and painting an additional color. I have white, black, gold, blue and a little bit of orange to put on here between all those rings and fins. What a nightmare!
 
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