Apogee Rockets Peregrine Jr quick-build

[novahobbies]

I found myself with a free afternoon, so what to do with it? Laundry? NOOOO! Vacuuming? Get bent! Paint the fins on the Flying Machine?
......well I could have done that, but NO! How about grab a model fom the stash and whip up a quick and fun 3FNC kit? Yeah! That's the ticket!

I grabbed my Peregrine Jr from the collection and got to work.


First up, the fins. They're multi-part fins, and made from a nice thin ply that has a smooth grain on the outer surfaces. Glued the parts together with Titebond II and set them aside.


The model moved fast. I mean, let's be real here. Most of us could do this without even cracking open the directions. I pre-read them, just in case, but there are no surprises here. I marked the tube, then built the engine mount and the coupler mounting point and set them aside.


Took a cat break while things dried


Came back to it a half hour later and started in on the fins. Gave them a quick sand to smooth out the glue, but I'll seal them later. For now I just wanted them on. Titebond II for the main joint, and 2 dabs of thick CA to tack them in place. I also glued the coupler into position on the upper half:


And finally, done for today. Not bad for about 2 hours....


I really like the shape of these fins. I'll go back tonight and apply some sanding sealer, and then sand them down tomorrow and apply Thick'n'Quick for fillets. Might even add some paint to it by tomorrow night, temperature depending.

 

[novahobbies]

I've got the Katana Jr, the Peregrine Jr, and the full size Zephyr....but I'm kinda thinking I need the Zephyr Jr just to complete the set of baby-HP models. These BT-70 based models really are a ton of fun to build and fly.

 

[novahobbies]

All I did yesterday was apply sanding sealer and smooth out the fins to a nice even finish. This morning I grabbed the model and went outside to apply a base coat of white, and a nice silver finish on the nose:


It *might* be ready for the red coat tonight, but Rustoleum is always a little iffy. We'll wait and see.

 

[neil_w]

Why the two-piece fins?

 

[Ron Soto]

All I did yesterday was apply sanding sealer and smooth out the fins to a nice even finish. This morning I grabbed the model and went outside to apply a base coat of white, and a nice silver finish on the nose:
View attachment 625524

It *might* be ready for the red coat tonight, but Rustoleum is always a little iffy. We'll wait and see.

yea... rustoleum i've found to takes forever to dry.. especially in cold weather. Lookin' good so far!

 

[neil_w]

It *might* be ready for the red coat tonight, but Rustoleum is always a little iffy. We'll wait and see.

Looks nice so far (especially that silver nose). Don't rush it with the Rustoleum and risk ruining it.

 

[Back_at_it]

It *might* be ready for the red coat tonight, but Rustoleum is always a little iffy. We'll wait and see.

Don't take the chance. Wait a coupe of days before the next color.

 

[novahobbies]

Why the two-piece fins?

I assume it has something to do with fitting them in the cutting window and saving space on the plywood, but thats just a guess. The Katana Jr also had multi-piece fins, and their X-15 fin setup looks like a jigsaw puzzle!

 

[novahobbies]

I went out to do another project, and checked the Peregrine. Yeah, even in Florida weather, she's still tacky. I'll just leave her the heck alone for a couple days. I'm in no rush. It's supposed to be a windy week anyway. Oh well. Nice time to build!

 

[novahobbies]

Given our wet weather, I think I'm putting a pin in this until at least the weekend. Wish I could move it along faster than that, but this 70% humidity is just a PITA for paint drying. At least I can say I'll have 4 rockets built and painted by the end of January. That's kind of nice. Now I just need to FLY them!

 

[mh9162013]

Why the two-piece fins?

I'm speculating, but I think it relates to the grains in the wood. If they were one piece, the bottom tips of the fins would have the grain going the wrong way making it far more likely they'll break during even a routine landing.

 

[novahobbies]

I'm speculating, but I think it relates to the grains in the wood. If they were one piece, the bottom tips of the fins would have the grain going the wrong way making it far more likely they'll break during even a routine landing.

If these were balsa, I'd 100% agree with you. As thin plywood though, I'm not so sure. You still might be right. And it's as good an answer as any!

 

[4regt4]

If these were balsa, I'd 100% agree with you. As thin plywood though, I'm not so sure. You still might be right. And it's as good an answer as any!

Actually, TVM did either a video or Peak of Flight newsletter (can't remember which.... ) explaining why he's using jigsaw fins. It's both for orientation of grain, and to be able to use narrower sheet stock for both production and packaging purposes.

Hans.

 

[Art Upton]

I went out to do another project, and checked the Peregrine. Yeah, even in Florida weather, she's still tacky. I'll just leave her the heck alone for a couple days. I'm in no rush. It's supposed to be a windy week anyway. Oh well. Nice time to build!

TWO WEEKS, like in the money pit...

 

[novahobbies]

TWO WEEKS, like in the money pit...

I gotta be me......IIIIII GOTTA BE MEEEEEEEE

LOL geez hadn't thought about that movie in forever. Totally goofy film. Can't say it was one of Hanks' best, but even in bad movies, he's fun to watch (ahem, Joe Vs the Volcano...)

 

[novahobbies]

Actually, TVM did either a video or Peak of Flight newsletter (can't remember which.... ) explaining why he's using jigsaw fins. It's both for orientation of grain, and to be able to use narrower sheet stock for both production and packaging purposes.

Hans.

Did not know that, thanks!

I set the launch lug a little lower down than in the instructions. I just didn't like it way up as high as it was on the body tube, but that's really just personal preference. That might make the middle vinyl wrap look a little funny (it has tabs to go around the now-nonexistent LL) but not really overly weird. I looked at the paint today, still giving off the smallest little smell, so we'll wait a couple more days. Oh well, that's what I expected.

 

[novahobbies]

And as of this morning, we are DONE! I wound up painting the red on late Thursday night, then let it sit until this morning to apply the vinyl.
Typical vinyl application, use a small spray bottle of water with a few drops of soap to wet the surface of the model and the backing of the vinyl. Slide into place, adjust as needed, slowly wrap around the tube, keep adjusting, and then carefully squeeze out the excess with a credit card and some paper towels. Easy easy.
Except it wasn't all that.
The metallic reflective appliques were MUCH more of a PITA than the regular vinyl. They weren't cut all the way through, so they had to be very carefully removed. I wound up attacking it by removing the excess and leaving the actual stickers behind. I only tore one meatball in the process, but I used that in the spot by the launch lugs (which I suspect will get damaged anyway).
I am waiting on the 24mm motor retainer that will come today, but I'm calling this done now. It was a super fun build. And now I'm SURE I need a baby Zephyr, to complete the set of three. These are really good sizes for park fliers.

 

[novahobbies]

I glued the motor retainer in place over the weekend. It was funny that the directions mentioned to glue it on with superglue. I suppose for a 24mm mount that it's fine that way, but.....eh. epoxy is just as easy to use as superglue, and it makes me feel a little better about it not popping off. Is it just me? Do people regularly use superglue for retainer rings? I have a half dozen models with 29mm retainer rings, and one with a 38, and I've only ever used epoxy...


I should probably reinforce that aft CR, now that I look at it. I'll do that tonight.

 

[mh9162013]

I glued the motor retainer in place over the weekend. It was funny that the directions mentioned to glue it on with superglue. I suppose for a 24mm mount that it's fine that way, but.....eh. epoxy is just as easy to use as superglue, and it makes me feel a little better about it not popping off. Is it just me? Do people regularly use superglue for retainer rings? I have a half dozen models with 29mm retainer rings, and one with a 38, and I've only ever used epoxy...
View attachment 626940

I should probably reinforce that aft CR, now that I look at it. I'll do that tonight.

I've only used 18mm and 24mm retainer rings, but I always use epoxy (JB Weld) to attach them to the cardboard MMT.

 

[Back_at_it]

I glued the motor retainer in place over the weekend. It was funny that the directions mentioned to glue it on with superglue. I suppose for a 24mm mount that it's fine that way, but.....eh. epoxy is just as easy to use as superglue, and it makes me feel a little better about it not popping off. Is it just me? Do people regularly use superglue for retainer rings? I have a half dozen models with 29mm retainer rings, and one with a 38, and I've only ever used epoxy...
View attachment 626940

I should probably reinforce that aft CR, now that I look at it. I'll do that tonight.

No. I used super glue for one 18mm motor retainer. I thought the same thing, it's only 18mm, it should be fine. Prep was the normal, sand the inside of the retainer, sand the tube, glue inside the retainer, and outside the tube.

Failed second flight. Rocket thankfully tumbled down with only a broken fin.

 

[novahobbies]

I've only used 18mm and 24mm retainer rings, but I always use epoxy (JB Weld) to attach them to the cardboard MMT.

Yeah I've used both JB Weld and regular 5 min. I suppose superglue would be OK for the smaller retainers, they don't get hot long enough to affect the bond, but I don't know. I like to make sure my motor mounts are nice and secure. I've seen too many rockets poop their MM at apogee and turn into beautiful lawn darts. Including one beautiful tragic one of my first Explorer Aquarius as a kid. Turned it into a mini Aquarius for a time before just giving up the ghost.

 

[novahobbies]

No. I used super glue for one 18mm motor retainer. I thought the same thing, it's only 18mm, it should be fine. Prep was the normal, sand the inside of the retainer, sand the tube, glue inside the retainer, and outside the tube.

Failed second flight. Rocket thankfully tumbled down with only a broken fin.

Welp, there's an answer. Superglue has great applications. This ain't one.

 

[Back_at_it]

Welp, there's an answer. Superglue has great applications. This ain't one.

Agree. I only use superglue for tacking stuff together before coming back with a real adhesive. Superglue is way to brittle for use anywhere else except maybe when papering fins.

I even stopped using it for gluing plastic nose cone piece together as is doesn't like the cold and I was popping nose cone bases off.

 

[novahobbies]

Agree. I only use superglue for tacking stuff together before coming back with a real adhesive. Superglue is way to brittle for use anywhere else except maybe when papering fins.

I even stopped using it for gluing plastic nose cone piece together as is doesn't like the cold and I was popping nose cone bases off.

That's pretty much all I use it for. I don't even like using it to secure a knot. Feels too brittle. For fins on LP and MP rockets, I use titebond II for the main glue, but I put a single dot of medium or thick CA on the leading and trailing end of the fin root to tack it while the titebond dries. I've heard some folks say that CA accelerator screws up the titebond curing but I've never run into that personally. Between titebond for the glue joint and epoxy fillets for inner and outer, I don't really worry about fins coming off my MP rockets unless I decide to stick something in there to make them hit Ludicrous Speed.

 

[mh9162013]

I only use CA glue for papering fins and that's only when I seal the edges.

 

[Imaknow]

And superglue has very little shear strength.
LONG ago, my boss thought it was cool to superglue a quarter to the shop floor just to watch people try to pick it up.
I walked by it one day, tapped it with the toe of my shoe on the edge and then picked it up 2" away from where it was glued.
He was pissed.
I kinda already knew about the shear strength, and only had used superglue for holding spar structures on balsa model airplanes to hold the wing ribs as it soaked in and I knew the covering actually carried the structural loads...

 

[Desfossr]

Why the two-piece fins?

I believe it is to change the direction of the wood grain and protect the fin tip from easily breaking off.

 

[bjphoenix]

I believe it is to change the direction of the wood grain and protect the fin tip from easily breaking off.

Papering helps with that a lot too, but maybe not enough for a fin that comes to a narrow point like that.