Thursday, January 27, 2011

Reviews: Three Nike Smoke-like objects

This post describes: a Quest Nike Smoke modified for 29mm motors; a cloned, stretched Smoke with a functional nose cone; and some Nike Smoke parts merged with a Tiny Tim booster.

Nike Smoke (29mm)

When it comes to flight profiles, I almost always prefer a ‘low and slow’ flight. You see more of the smoke, and hear more of the noise. You see the whole flight, including ejection. Moreover, you maximize the odds of finding your rocket! However, it seems that I always have to have one ‘disposable’ 29mm rocket in my fleet. At the last MDRA launch, someone returned my Negative Camouflage, which I thought I had lost on an F10. To celebrate, I put her up on an E9. Well, the rocket hung on the pad, went horizontal, found a large launch rail, and pretty much disintegrated. I was in need for another disposable, when I found a Quest Nike Smoke at the Performance Hobbies tent. It appeared to be just the right diameter for a 29mm mount, and I thought the plastic cone and fin can looked cool.

For this modification, I retained the cone, fin can, body tube and launch lug. The rest went into the parts bin. I never found the plastic tip for the cone. I don’t know if it was missing, fell into the couch, or whatever. I decided not to worry about it since the cone doesn’t look bad without it, the epoxy and weight that I’ll have to put into the nose will provide plenty of support, and I will probably lose the thing anyway. I glued the two pieces of the cone together using thin plastic cement.

I tested both LOC and Giant Leap 29mm tubing and found the LOC tubing was perfect. The ID of the rear of the fin can is a little bigger than the OD of the tube, but the 29mm tube fit nicely into the fin can’s shoulder. It wouldn’t slide all the way through because there is a small lip at the tip of the shoulder, which I promptly ground off. To provide more support, I cut about a 1" section off some junk tube I had laying around, sectioned it, and found it made a perfect adapter for the aft end. These components were epoxied together.

The kit came with a piece of Kevlar® string and some round elastic. This would be fine for the stock kit, but I decided to use the Kevlar® string and long piece of heavy, bright orange, tubular elastic (approximately 4') from the Negative Camouflage (not much else was left). I looped the Kevlar® around the front of the motor tube, and epoxied the fin can assembly into the body tube. To make room for all this cord and a streamer, I cut the back end off the nose cone. I knotted the elastic and buried it in a mix of epoxy and lead shot at the tip of the cone. I put in enough weight so that the CG would be approximately 14" from the tip of the nose. Plenty to keep it stable on a G80.

That’s about it. I also attached the plastic lug provided with the kit using epoxy.

I didn’t want to put much effort into finishing so I left most of the rocket alone. The whole rocket was already white, so I just painted the fins fluorescent red and yellow, and the nose cone tip black. The kit came with peel-off lettering for the ‘UNITED STATES.’

I decided to use a wimpy F23-7 for the first flight as there was over 10 mph winds. I made a masking tape retainer and filled the lower portion of the body with dog barf wadding. I used a 5' length of 1" fluorescent red plastic tape as a streamer. I wanted to use the wider streamer recovered from the Negative Camouflage, but couldn’t find it at the last minute. The thinner streamer is a little too small for a soft recovery, but it should help make the recovery visible.

The rocket disappeared in a cloud of dark smoke and didn’t re-appear until the end of the day. It was at the edge of the main field, away from where we spotters were looking. My thanks to Richard Hickok for finding it! It was in perfect shape and is ready to go again.

I normally am not a fan of simple kits, but I have to say this kit impressed me. The plastic parts were good quality and the detailing is great. The recovery components are also nice. I really like the Quest’s chutes better than Estes’ chutes (even though I didn’t use this one). Finally, at $8 the price was right. The conversion was easy and it held up fine on the F23 with what was probably a fairly hard landing.

Nike Smoker

This article describes how I went about making a 'functional' Nike Smoke nose cone from Quest components. 'Functional' is probably a poor choice of words, but describes my goal.

The purpose of the Nike Smoke system was to visually test upper atmospheric winds. Its nose cone was filled with various chemicals (titanium tetrachloride in the final operational version), which would produce a visible trail when released. During powered flight, an inlet pipe in the tip of the cone would force the TiCl4 out ports in its base. The resulting trails were visible to 75,000 ft.

When I read about a 'vintage' Enerjet kit with a working nose cone (see attached sketch), the gears began turning.

The basis of this build are the Quest Nike Smoke cone and plastic fin can. This fits their T35 tubing. I used a variety of parts to complete the rocket.

In a previous Quest Smoke conversion I found that, with a little grinding, a 29mm phenolic tube fits pretty well in the plastic fin can. So, I used a small piece of Giant Leap 29mm tubing and then mounted a 24mm tube in that. A Kevlar® leader is tied to the neck of the fin can. An elastic shock cord is tied to that Kevlar® and to the nose section.

As I was thinking about the cone modification, I realized that I probably wanted access to the base of the cone so I added a payload section. I made this from a short piece of the T35 tubing, a piece of phenolic liner for a 38mm EX motor, a hand cut bulkhead, and loop of 1/4" Kevlar®.

For the launch lug, I used a long piece of 6mm tubing on top of a balsa stand-off. The 6mm tube fits a 3/16" rod well enough. The standoff is needed to clear the Nike Smoke cone.

Now, on to the star of this attempt to make a functional Nike Smoke cone. That is, one that will spew tracking powder as it boosts. You can see the guts in the photo. The anticipated airflow is shown with the arrows.

I cut the tip off both halves of the cone and affixed an Estes lug in one half with a dab of hot-glue. This lug feeds air into a First Fire igniter tube. I built-up the lug with some tape so it was snug in the larger tube. The holes in the lower part of this tube should then blow the powder out a vent in the cone itself (which wasn't cut when the photo was taken).

The orange plastic cap fits almost perfectly in the cone's shoulder and is used to help guide the tracking powder out the vent hole. A conical shape would have probably been a better choice, but that's the best thing I found. The single vent was later cut in the the short transition section just above the plastic insert and aligned with the lower hole in the First Fire tube. The ear plug protruding from the end was replaced with a removable dowel plug that extends to the bottom of the lower hole.

Prep of the rocket itself was typical: friction fit a D12-7 motor, add dog barf wadding and attach a 12" nylon 'chute.

I filled one half of the cone with orange tracking powder and taped the two halves together. The intake and vent ports were also taped-over until it was on the pad.

The flight was good and a lot of the powder was ejected. Viewing the video on my computer, you can see a hint of the powder after ignition. I attached a screen snap and you can barely discern a reddish tinge to the otherwise white exhaust. On recovery, there was also all over the side of the rocket body. All-in-all, it was not impressive and was a big mess.

I succeeded in modifying a Quest Nike Smoke cone so that it ejects tracking powder during boost. Unfortunately, there was little visible evidence during the flight and it was messy. So, I plan to wash-up the cone and glue it together. I could load more powder through the plug in its base. However, future flights will probably be without tracking powder. Please comment if you have ever tried this or have heard of others doing so.

Tiny Tim Smoke

This will be a short review of a recycled rocket. The Tiny Tim Smoke is a rebuild of a scavenged Tiny Tim Booster section from an Aerospace Technical Products (ASP) WAC Corporal. What this review does show is how seemingly non-compatible parts can unexpectedly come together to yield an interesting rocket.


Parts List:

* One scavenged Tiny Tim Booster
* One Quest T-35 tube
* LOC 24mm tubing
* One Quest Nike Smoke nose cone kit
* Steel fishing leader
* Elastic cord

I inherited a box of dead rockets from rocket buddy Paul Miller, who was relocating to Aridzone (that place just east of The Peeples Republik of Kalifornia). One of the rockets was a burned out (literally) Tiny Tim booster from a WAC Corporal kit that met its demise at NARAM-47 on a C11-0. The top, including the inter-stage, was fried and there was no motor mount tube. At first, it appeared the body's diameter wouldn't match any tube that I had on hand. I was thinking about adapting it up to a larger tube when I noticed that a Quest T-35 tube (1.340" ID x 1.380" OD) fit over it like a glove!

To get the T-35 to slide all the way to the fins, I had to pare one of the outer trim rings that were part of the WAC's scale detail. I also scuffed up the paint to help it bond to the T-35.

I sanded and trimmed the centering rings so I could get a new 24mm motor tube in. The top of the Tiny Tim Booster had thick ring installed, which provided an attachment point for the recovery leader. I poked a hole below the ring and looped a steel fishing leader through. These leaders are so thin that the T-35 still fit nicely.

The only cone I had for the T-35 was one of Quest's 3-part Nike Smoke cones. I really like this cone style. The cone consists of two halves and a conical cap. Chris Michielssen has a good description of the cone and how to build it. I didn't do as good a job but it still looks cool. I tied the cone to the upper loop on the steel leader with a long piece of elastic.

The body and cone was painted gloss black to match the Tiny Tim and I trimmed the raised rings with silver vinyl tape.

Prep included grabbing and attaching a 12" nylon 'chute, adding the dog barf wadding, and friction fitting a C11-3. The flight was great.

I hope this motivates you to resurrect your dead and retired rockets and rocket parts. This was a lightning fast build and the resulting rocket looks pretty cool, if I do say so myself.