Hangar 11 4" X-15 Build

[KenECoyote]

Hello!

I've loved the X-15 since I first set young eyes on it many years ago. When I started launching more and more rockets in the past year or two, I was very disappointed that there was a scarcity of X-15 kits. How can such an incredible "rocket", not have a rocket modeled after it readily available? There were some OOP Quest and Estes (and once in a blue moon - Shrox) kits on Ebay, but the prices were just too nuts for me, so I started looking at larger options.

My search led me to find 6" and 4" X-15s. I'd love the 6"; however that is quite a beast and I'm happy with the 4" bird (for now).

The 4" is available from Bobby at Hangar 11 hobbies (https://hangar11.com/x-15-4-dia-new.html) and it was very fortunate for me that he was about 30 minutes drive away from me! Bobby is busy with some other things nowadays (Star Wars business is really booming!); however he took the time to discuss the kit and sell one to me. I left the hobby shop with a box of parts and high hopes.; however I wanted to take my time with this one since it has non-conventional construction and it's relatively pricey given that it has so many parts, a unique nose cone and full body wraps.

Pic from the Hangar 11 website of the 4" X-15 they sell:

Fast forward a few months and many rocket flights later and I'm ready for this bad bird! :grin: When I first researched this kit, I was surprised how little information was available on it...I think someone started a build thread, but it just died and now I can't find the link.

BTW - I'll try to update every once in a while with the goal of finishing for the next club launch in about 2 weeks. Hopefully my OCD will allow me to power through this to the deadline and launch if before year end (note that the last club launch in Nov may very well be cancelled due to nasty East Coast November weather). Apologies in advance if there are any hang-ups...life happens, so try to enjoy the journey.

 

[KenECoyote]

The unique feature of Hangar 11 kits is the use of interlocking pieces to hold the wings & fins in place. The root of the fins/wings fit into holes in the slots of the CRs (Centering Rings) and the assembly is then bolted together inside the bt (body tube).

Here's a pic of the forward wing set assembled outside of the bt:

 

[KenECoyote]

I had also discussed options for DD (dual deploy) or DeD (Delayed Deploy) with Bobby and he noted that I could use a Defy Gravity tether. I figured that cable cutters would also be a possible option since the Defy Gravit tether wasn't in production any longer. As I continued building, I'm thinking now that HED (Head End Deploy) similar to the Punisher would be a very good option here due to all the room in the nose, so I may go that route. More on that later...

 

[DizWolf]

From what I've seen on most X15's they need a brick in the nose to fly....may not be room for HED.

I've also searched these out a bunch, very little info out there. A few started builds, but then they peter out.

I'm considering building a 4" out of parts I've got kicking around. Nose and shrouds are going to be... interesting.

I've considered dual 38's to copy the early engines. but.... lighting them off would add a level of pucker....

 

[KenECoyote]

Bobby provided detailed instructions on the building; however in full honesty, I found them hard to follow. It's more likely me since I'm more visual and found myself re-reading the instructions several times to understand what was being said. Then again, this is a very different construction method from pretty much all other standard rocket kits.

Bobby used construction borrowed from his "glueless" rocket kits. Those allow you to pretty much assemble the rocket (CRs, fins, etc.) by bolting the assembly together and you could very well assemble one of those kits on the field, fly it and then when you're done, disassemble it and take it home. I like the concept and do plan on buying one of the those kits in the future. However since the X-15 kit uses a full shroud which is glued on, this kit pretty much isn't one you can disassemble. Still, I like the construction and found it to be very strong and boy, it sure must have taken a lot of engineering!

 

[KenECoyote]

From what I've seen on most X15's they need a brick in the nose to fly....may not be room for HED.

I've also searched these out a bunch, very little info out there. A few started builds, but then they peter out.

I'm considering building a 4" out of parts I've got kicking around. Nose and shrouds are going to be... interesting.

I've heard the same and expect maybe 2-3# to be added to the nose...we'll see. :wink:

 

[KenECoyote]

First step is to inventory all the parts! Highly recommended since there are a LOT of small parts. Each of the three main assemblies (wing, tail fins, tail cone) uses CRs, bolts, nuts, washers and such.

Also it is recommended that you test fit everything. One of the CRs I got was cut off-center and so it wasn't quite working out (Bobby noted to me that my kit has laser cut wood; however future kits will use regular die-cut (?) wood CRs...which I would think would eliminate this type of off-register error

Bobby got me another CR lickety split, so customer support was very good! I guess it's helpful to be able to visit him. :wink:

 

[KenECoyote]

Before I begin the build description, I should note that I"m at the point where I've gotten one of the body wraps/shrouds cut and mostly fitted on (many are daunted by this part), so I'm fairly well into the build. Still, I've had a small hitch, so I'm using the break to start this thread.

 

[cbrarick]

I've got that one in a box, with the 6 inch, and the fiberglass 6 as well...
gotta get them built

 

[KenECoyote]

I've got that one in a box, with the 6 inch, and the fiberglass 6 as well...
gotta get them built

If you need help cleaning out your house to gain some space, let me know! :wink:

I was considering the 6" from Smokin Rockets; however I was split...the FG costs only a bit more than the phenolic, so I would want it; however the FG is really a pig/brick from what I've read and it ends up pushing the price into the "quite pricey" group.

 

[Cl(VII)]

Most kits do not really excite me. This is a definite exception as the subject matter is one of the all time most awesome things ever constructed by man.

 

[KenECoyote]

Step 1 is "Inspect the kit for completeness and any transportation damage." Always a good first step!

Step 2 is to square off the round edge in the bt slots. This kit uses a PML phenolic bt and Bobby has PML cut the slots for him; however the cutter used is a round bit and the wings/fins have square shoulders, so you need to "square off" the oval holes. Of note is that mine (and I've read at least someone else's had the wing slot too small/short. Bobby replied to widen the slot as needed evenly on both sides. I think the fin and wing holes were cut to the same length even though the wing root is longer, so I measured how much longer the wing root is (10mm?) and widened the wing slot by half that on each side.

Pic of wing slot being widened & squared off - I used an Xacto knife for vertical cuts and Xacto saw for the horizontal lenghtening:

You should test fit the fins and wings by inserting the longer tabs all the way in first and the rest should drop in.

 

[KenECoyote]

Most kits do not really excite me. This is a definite exception as the subject matter is one of the all time most awesome things ever constructed by man.

Thanks! I also feel the same way!

No need for PMs...the link for the kit was in Post #1: (https://hangar11.com/x-15-4-dia-new.html) and price is in the upper right corner (assume the higher price).

 

[KenECoyote]

Step 2 later notes "OPTIONAL: Air foil the leading edge of the fin sets at this time if desired".

Normally I don't air foil since my club field has a relatively low waiver and tricky conditions where rockets can land in a tree or even river, so I've preferred to forgo the air-foiling and go with the strong-but-chunky fins. However this rocket is different and I felt it would be a shame to not air foil the wings when the rest of the rocket looked so good and streamlined. I have a full sized router buried somewhere in my garage/basement/house; however I wasn't in the mood to climb over stuff and dig for it, so I tried out the Dremel router table with a 618 bit (45 degree cut). I found it just about perfect for what I was looking for and it mounted in minutes, is compact so I didn't need to clear any more room on my bench and I also had an old Dremel Model 1 lying around I had no use for, so I got it off Amazon for $30 (note you need to supply your own Dremel tool) and it made really quick work of the 1/4" plywood wings/fins! I just used a sanding sponge to finish them off:

 

[KenECoyote]

Step 3 is to fit all the CRs (2 forward CRs for the wings & 3 back CRs for the fins...the last being doubled in the back and extending out about 1/8" so you can glue the tail cone to it).

So sand, sand, sand. Wasn't too bad, but not one of my favorite things. Additionally, I inserted the motor tube into the aft CRs to ensure everything was in alignment. I did have to sand a bit of the middle hole in the CRs. The front CR center holes are 38mm, so I used a 38mm RMS motor to check that fit.

 

[Cl(VII)]

Thanks! I also feel the same way!

No need for PMs...the link for the kit was in Post #1: (https://hangar11.com/x-15-4-dia-new.html) and price is in the upper right corner (assume the higher price).

Sorry, I had a moment there. I must have been overcome by the shear awesomeness of this kit.

 

[KenECoyote]

Sorry, I had a moment there. I must have been overcome by the shear awesomeness of this kit.

I don't blame you...I often have to remind myself to put my tongue back in my mouth while working on this. LOL

 

[Kruegon]

I've been considering an upscale clone of this in the 2.6" range with a 29mm MMT. I may forego that idea now since this kit is available. I need to be flying more 38mm anyway.

Does anyone have a list of the recommended motors for this kit?

 

[KenECoyote]

Step 4 Tail cone prep

Here is where I hit another snag. I had the tail cone lying around for months and kept it together with the other parts; however when I was finally ready to start the build, I couldn't find it! I started tearing through the house and anywhere it could be to no avail. I then emailed Bobby and he said he could sell me another tail cone and if/when I find mine, I could just bring it back for a refund. Great guy!

However just a day or two later, I decided to check around the floor on the other side of my bench and lo and behold, there it was hiding in the dark behind one of the bench legs! I'd guess it was put on that corner of the bench and then fell when I wasn't aware. Additionally, it being black camouflaged it very well back there!

Okay, tail cone in hand, I followed the directions to sand the interior and then add T-nuts to the Tail cone CR...let the hammering commence!

The instructions didn't mention it, but I later added epoxy over the edges of the T-nuts since in my experience, they can be pushed out without too much force and once pushed out, it is hard to fix back in place.

Next you place the tail cone CR into the Tail cone and drill pilot holes, then larger. This is for the rear motor retainer which is included with the kit.

I decided to test fit the motor tube into the tail cone and good thing I did since it wasn't going in. This was because the lip in the mt hole of the tail cone was warped slightly inwards and maybe it wasn't trimmed close enough. I used a Dremel with a cut-off while to trim some of the ring off, then I used a small round sanding drum bit to sand until the motor tube fit well. Note that the motor retainer is at the top above the cut piece.

After that, you epoxy in the tail cone CR - make sure you don't get epoxy on the T-nut threads/bolts.

Here is a pic of the tail cone CR in place with the holes drilled and I'm using the motor retainer bolts to hold the CR in place while epoxying it in.

Here is another pic showing how I added more epoxy on the edges as well as over the T-nuts:

 

[KenECoyote]

Step 4 continues (maybe it should be step 5?) with instructions to fit each fin in the BT slots to ensure they move well without binding/getting stuck. I had already done this while squaring off the bt slots, so this wasn't necessary for me, but always good to do a second check.

At this point, I noticed that the tail cone looked like it was cut off-square. A good build practice is to make sure everything is square...especially any type of cut, so I looked into this more and even did a prelim test fit against the last CR which extends out of the bt and is used to glue the tail cone to.

Here you can see that the tail cone base is slightly off. I used the motor tube and a motor casing to line things up to check:

 

[KenECoyote]

So at this point I was split...should I take the time to square off the base of the tail cone or just use it as it is and use filler afterwards. If I square it off, it would mean cutting some of it down and the way it is made to fit over the last CR, cutting it down would mean that the gap would then extend all around. In the end, I decided I'd rather cut it square and sand the edges of the last CR to fit into the slightly shorter tail cone.

How to square it off was a bit of a challenge since 4" was too much for my band saw and the shape of the tail cone (plus it having a smooth slippery surface) didn't lend itself to using a miter saw. In the end, I used the supplied bolts, measured out where the shortest side is, set a nut on each bolt the same distance, and then screwed through the last CR (which I beveled by this point) into the tail cone so I could see where to cut.

After that, I used an Xacto hand saw (love that tool!) to cut off what was needed.

Viola! :grin:

 

[CrazyOB]

As usual lovely work Ken. Does the tail cone get 'permanently' bolted on or is it able to be removed later? If the latter, I would mark it 'Top' on the inside.

Yes, those Xacto saws are great! I keep a pair of them handy, as I am always looking for one.

 

[KenECoyote]

As usual lovely work Ken. Does the tail cone get 'permanently' bolted on or is it able to be removed later? If the latter, I would mark it 'Top' on the inside. Yes, those Xacto saws are great! I keep a pair of them handy, as I am always looking for one.

Thanks CrazyOB! The tail cone and aft CRs are glued together well as onto the motor tube (note that while this kit utilizes some of the glueless construction, it is NOT entirely glueless and later the wraps are glued over the fins, body and wings). I had beveled the rear most CR so the cut down tail cone can sit flush, so no worries about flipping it. Still, a great suggestion and I have already marked some items earlier (I put "Top" and "Bottom" on the body tube and similar on the wraps to avoid confusion since this rocket isn't symmetrical top to bottom.

 

[Brent]

The hardest part of the build is slotting the body wraps for the tail and wings. Take your time and measure very carefully.

 

[dixontj93060]

The hardest part of the build is slotting the body wraps for the tail and wings. Take your time and measure very carefully.

+1. In the end though the shrouds on my 6" diameter fit almost perfectly.

 

[KenECoyote]

The hardest part of the build is slotting the body wraps for the tail and wings. Take your time and measure very carefully.

I would agree with that since it doesn't seem that you can't accurately measure and mark it since the wraps extend out from the bt and the rear fins are at angles. Additionally, the side edges of the wrap gradually transition to a rounded surface. Still, I've measured carefully and tried several things and got one side on and I think it looks pretty darn good so far!

Juicy preview: :grin:

Half-naked soft rocket p*rn! :wink:

 

[KenECoyote]

Here's a close-up pic of the last CR extending out from the rear bt (Bobby would call this "proud"). Note that I've beveled the edge to fit the tailcone...if you're building this kit, you many not need to do this step since I did it after squaring my tail cone (which effectively shortened it a bit).

BTW - this is a test set up...note that I don't have lock & flat washers on under the bolts.

 

[Brent]

I would agree with that since it doesn't seem that you can't accurately measure and mark it since the wraps extend out from the bt and the rear fins are at angles. Additionally, the side edges of the wrap gradually transition to a rounded surface. Still, I've measured carefully and tried several things and got one side on and I think it looks pretty darn good so far!

Juicy preview: :grin:

Half-naked soft rocket p*rn! :wink:

When I built mine the wrap went the full length of the tube. They must have changed that.

 

[pyrobob]

This kit looks SOOOO COOL! Must resist....

 

[KenECoyote]

When I built mine the wrap went the full length of the tube. They must have changed that.

Hey Brent, did you build the 6" or 4"? If it is the 4", then it is likely that some changes occurred and maybe the tube wasn't cut down any longer. I did confirm with Bobby that I need to cut the bt down after gluing on the wraps. Note that this is a small/slow production run kit, so small changes may happen along the way. Bobby already noted that the newer batch of CRs will no longer be laser cut.