Anyone else building the Apogee X-15 rocket?

[KILTED COWBOY]

Got it over the Christmas holiday and just started building it last few weeks.
Not too difficult of a build but I am wondering how well it is going to hold up to launches and landings.
Balsa fin material is pretty flimsy and the front and rear fins go into a slot in fairings that is molded thin plastic that you cut out from a sheet and superglue onto the body tube.
The fins are then super glued through slots on the fairings to the body tube that is hidden by the fairings. You cant tell if you have a good bond or not.
It is going to be a nice looking rocket, just not sure it will stand up to flight and landings. I have never used so much super glue to attach high stress components to a rocket before.

 

[KILTED COWBOY]

A few links form Apogee website on build so you can see what i am talking about.

https://www.apogeerockets.com/Advanced_Construction_videos/Rocketry_Video_317
https://www.apogeerockets.com/Advanced_Construction_videos/Rocketry_Video_319
https://www.apogeerockets.com/Advanced_Construction_videos/Rocketry_Video_320

 

[Ez2cDave]

Here is a pic of Tim Van Milligan with a completed Apogee X-15 . . . A "motivator", I hope !

Dave F.

 

[Apogee Components]

I'll say that using the exact steps listed in the instructions, ours flew and survived several flights with no damage. The prototypes had some occasionally different stories, mostly to deal with a loss of stability, and we addressed those before the kit release.

None of our flights failed due to adhesive choices though, so hopefully that gives you some more faith.

That all said, if you wanted to attach the fin using wood glue at the root, I see no harm in that.

 

[KILTED COWBOY]

I'll say that using the exact steps listed in the instructions, ours flew and survived several flights with no damage. The prototypes had some occasionally different stories, mostly to deal with a loss of stability, and we addressed those before the kit release.

None of our flights failed due to adhesive choices though, so hopefully that gives you some more faith.

That all said, if you wanted to attach the fin using wood glue at the root, I see no harm in that.

I wish you would release the assembly videos in some kind of order. It is hard to follow them when they are coming out so sporadically and in no kind of order. The videos do help in conjunction with the printed instructions. i am glad your tests show adhesive used is working just fine. I am taking my time with this build and hope to have a nice flying model. Thanks for the response.

 

[Apogee Components]

I feel you on that, and I made the case to just release all of these, but we chose to go another way for now (we just have a whole lot of plates spinning right now, and releasing this way allows us to focus on getting the RockSim update out & the 3D visualizer released). That said, after we release video #6 later this month, they will all be coming out in order from then on out (and perhaps in bulk). My sincere apologies for any inconvenience there.

No problem. If you come across any other questions or concerns, feel free to reach out!

 

[markschnell]

after we release video #6 later this month, they will all be coming out in order from then on out (and perhaps in bulk). My sincere apologies for any inconvenience there.

Please release them in bulk. If they're already made I don't how it would take any more time to release them all at once or one at a time. The way you guys have done these makes no sense at all.

 

[markschnell]

@KILTED COWBOY We've got a few different threads here where we've been discussing this kit and the builds.

 

[Apogee Components]

We tried to start with the hardest parts of the build, which is why we have jumped around. Again, I'm sorry for the inconvenience.

 

[Astronaut Cheeseball]

We tried to start with the hardest parts of the build, which is why we have jumped around. Again, I'm sorry for the inconvenience.

The X-15 kit was an absolute pleasure to build were excited Apogee took the time to produce it. Following the instructions to the tee will insure the best results. We love this kit so much we purchased another one!

 

[MikeT]

This ones on my short list.

Mike

 

[Antares JS]

It's in my build pile right now and I picked up an F26 motor for it from our FLRV. Most likely will be built and flown in summer. I was also skeptical of using CA alone to bond the wings, but in my experience, Apogee has pretty high standards, so I'll probably end up trusting them.

 

[jddj]

Balsa fin material is pretty flimsy

I'm building mine now, and I applied and sanded one layer of CWF, then fiberglassed the balsa parts with 1 layer of 3/4oz fabric, West System epoxy as the resin, vacuum-bagging each fin (with a food -grade vacuum sealer and Teflon-coated release and polyester absorbent from Aircraft Spruce).

The fins look great, feel as strong as plywood (if not stronger), but light as balsa. Maybe just a little teense heavier, but not much.

When you apply fiberglass, you need to be aware that forces that would originally have caused fin flex will now be transferred strongly to the root, so you need to be sure root attachment is really good. For most rockets I glass, I switch to TTW attachment, if it's not that setup already.

I know this is an old thread, but I keep finding it in search results, so I am leaving this here for the next guy to find.

 

[OverTheTop]

I might have to get one of these, even with the stiff international postage. Looks great.

 

[Astronaut Cheeseball]

Built one when Apogee first released the kit. Flew successful on an Aerotech F67-W to 1306ft. I reinforced the vacuum form rails in the rear everything else was built to Apogee specs. I have another one waiting in the build pile which I'm thinking of making a modified X-15 Delta Wing.

 

[KenECoyote]

The balsa wings were also a small concern of mine...so no reported issues of breakage?

 

[jddj]

I did a fiberglass wrap of the last 1/2 inch of the motor mount tube, to give a surface that would withstand repeated tape removal.

I vacuum bagged with an old DMS motor casing as a mandrel (sparing you the details of the process), but it only came out so-so. It'll function, and it's light, minimal, but it's not pretty.

There's a mylar-wrap process I've heard recommended for fiberglassing, and I'll try that next time I have this kind of wrap to do.

Pictured is the tail end of the MMT, glassed, and inside permeated with CA, sanded and tidied up.

 

[Astronaut Cheeseball]

The balsa wings were also a small concern of mine...so no reported issues of breakage?

No problems with the balsa fins and that's landing on a dry lakebed. I added an anti-zipper protection on the Kevlar shock cord.

 

[jddj]

Enclosed: my OpenRocket file (for current OpenRocket beta 22.02.beta.04 and later) of my X-15 as built.

A few things:

1. Not yet flight tested against this set of sims. Will try to remember to follow up after flying.
2. My build is heavy: 180g heavier than the RockSim model. Weigh yours as you go and adjust. A few weight items to note: my fiberglassed balsa fin set (change OR material setting), my Eggtimer Apogee and Easy Mount (remove from model if not using), a little too much nose weight (did mine with epoxy and BBs, crossed wires to anchor), lot of filler to blend in the chines, more paint than ideal (weigh yours and adjust the masses).
3. Model correctly predicts C/G with a motor (pictured balanced on a finger (blurry shot, sorry); motor simulated for weight and length).
4. RockSim predicts C/P at 45.5 cm, OpenRocket predicts C/P at 49.3 - OpenRocket predicts a better margin of stability, but the .ork file's rocket design is different from the .rkt file's. Hard to imagine which is correct - though horse-sense wise, OR looks closer to me.
5. Bottom image is from the OpenRocket photo studio. Placing all the decals in there is an exercise left for you.
6. Finished mine with satin clearcoat. Yes, I know it's supposed to be flat, but given the likelihood it'll land in mud occasionally, nope.
7. Why yes, that is a vintage Digi-Comp I visible beneath the lower tail fin. One owner.

I tried to weigh things component-by-component, but there are a few fudges in there. I started with the RockSim version and made a number of mods, fixes and adjustments.

Don't just use this blind. If nothing else, the weights differ from yours. It's intended as an easier OpenRocket starting point for the X-15 than I had to start.