Semroc My Boid

[JAL3]

I've had my Boid sitting around for a long while but had no real plans on building any time soon. After all, its pretty basic and had nothing to really pique my interest. I changed my mind, though, during a recent build of another rocket. There I tried using label paper to "seal" the balsa fins. While posting about it on TRF, I got some advice on how to do a better job of it and wanted to give the technique a try. The Boid seemed like the perfect victim for my learning experience.

 

[JAL3]

There are apparently several variants to the My Boid. My kit came with three balsa fins but the instructions indicate that there are also versions with 4 fins. The first step of the instructions is to determine which you have and then select the correct fin marking guide. I lined up the body tube one the 3 fin guide and then marked the aft end. An angle was used to extend the lines.

 

[JAL3]

The next step was to insert the engine hook in the precut slit. As I was doing this, the Kevlar harness had a loop put into one end and slipped around the hook.

 

[JAL3]

Instead of centering rings, this kit has more of a centering tube. It was slid over the engine hook and glued into place.

 

[JAL3]

The nosecone was one of the smoothest and nices pieces of balsa I have ever received. Instead of using regular filler, I decided to seal it with a layer of thin CA. It was drizzled on and allowed to soak into the wood then set aside to dry.

 

[JAL3]

As mentioned before, my Boid came with three balsa fins. They were in good shape and quickly removed from their parent material. I then sanded the leading edges round and tapered the trailing and outer edges.

 

[JAL3]

Next came the real purpose for this exercise. Previously, when I had used label paper to seal a fin, I would press the unsanded fin flat on the paper and then trim away the excess. I would then turn the fin over and do the same thing on the other side. Then I might, or might not, try to sand the desired profile into the fin.

This time, I took the sanded fin and laid it flat on the label paper. The fin was then "rolled" about its leading edge and pressed into the paper on the opposite side. This allowed the paper to follow the contour of the leading edge and provided for a much cleaner appearance. The label paper was then pressed flat against itself at all the other edges and a razor blade was used to trim away the excess.

It was not a perfect job but I think it will get better with practice and when I find my X-acto knife.

 

[TheAviator]

I was looking at the pictures of the motor mount, and was wondering if there was a motor block included. If there isn't, I would recommend putting one in. I've had rockets that, after a couple of flights, had the motor hook tear through the motor mount tube. I've only had this happen twice, and the motor has not completely flown through, but the rear end of the motor tube was singed and unusable. I've since beefed up the attachment of my hooks, but when weight is not an issue, I still add an engine block for added security.

Just think, most of the force of the engine is being transferred through that tiny little tab on the end of the motor hook, and by association, the glue joints holding the hook on. The steel doesn't always bond well, which causes this problem.

 

[JAL3]

I was looking at the pictures of the motor mount, and was wondering if there was a motor block included. If there isn't, I would recommend putting one in. I've had rockets that, after a couple of flights, had the motor hook tear through the motor mount tube. I've only had this happen twice, and the motor has not completely flown through, but the rear end of the motor tube was singed and unusable. I've since beefed up the attachment of my hooks, but when weight is not an issue, I still add an engine block for added security.

Just think, most of the force of the engine is being transferred through that tiny little tab on the end of the motor hook, and by association, the glue joints holding the hook on. The steel doesn't always bond well, which causes this problem.

While writing this up, I wracked my brain trying to remember if one had been installed. I have no specific memory of putting it in but that was a while back. Next time I'm at the shop I'm going to have to look and see if one is mentioned in the instructions and, if so, see if I have any extra pieces floating around.

I agree that that lack, if there is a lack, is a serious problem with longevity. I discovered that fairly early on with an Apogee Diamondback.

 

[JAL3]

The mounting of the motor mount into the airframe BT should have been a simple matter and it was. I managed to mess it up anyway. I was supposed to leave about 1/4" of the mount protruding from the end and I made the appropriate mark on the mount. I then swabbed some white glue inside the BT and inserted the mount. It was a tight fit and I really had to put some effort into the pushing. All of the sudden it moved...too far...and would not move again. My motor mount is usable but pushed in just a bit too far.

 

[JAL3]

As the motor mount glue continued to dry, I mounted the eyescrew in the nosecone and added a bit of white glue to the threads to make it hold better.

 

[JAL3]

In order to promote a stonger joint between the fins and the BT, I used a needle to poke a series of holes along the mounting line. I pricked a similar series of holes in the root edges of the fins. The fins were then glued in place using a double glue joint of white glue.

 

[JAL3]

As the glue on the fins set up, I also applied the launch lug flush with the aft end using white glue.

White glue fillets were applied to all the fin roots over the course of 2 days.

 

[JAL3]

All that was left of assembly was to tie the elastic to the Kevlar and then to the nose cone. It was an easy build.

 

[JAL3]

Finishing of My Boid began with a decision about what I wanted it to look like. I decided to try and keep things in the "bird" family and was wondering how to reconcile that with my lack of artistry. I looked over towards my paint shelves and saw blue and orange, two colors I seldom use. Then and there I decided that my My Boid was going to be called the Roadrunner, the mascot of my engineering school. (UTSA Roadrunners) The school colors are blue and orange and it seemed a simple enough idea.

I gave the rocket a gentle sanding, brushed it off and then sprayed on two coats of white primer. The primer was given 2 days to dry.

 

[JAL3]

When the 2 days were up, I gave the rocket a light sanding and then applied 2 coats of orange.

 

[JAL3]

The orange was given an opportunity to dry and then the fins and nose cone were masked so that the BT could be painted blue.

 

[JAL3]

It was then set up in the booth and given 2 coats of blue.

 

[Buzzard]

Great build threat, John. I got a "My Boid" kit when they first came out. Apparently each kit is a grab-bag of parts. Mine was a ST-8 tube with an elliptical nose cone and the FSI Competitor elliptical fins. It went together well and I went with an all-over red paint scheme. Flew it at a DARS launch on an A8-5 and it really scooted. In fact, most of the observers thought that it was flying on a B motor.
I purchased two more kits and they are buried in the build pile.

Chas

 

[JAL3]

Great build threat, John. I got a "My Boid" kit when they first came out. Apparently each kit is a grab-bag of parts. Mine was a ST-8 tube with an elliptical nose cone and the FSI Competitor elliptical fins. It went together well and I went with an all-over red paint scheme. Flew it at a DARS launch on an A8-5 and it really scooted. In fact, most of the observers thought that it was flying on a B motor.
I purchased two more kits and they are buried in the build pile.

Chas

Thanks for the kind words.

This really was one that I had no real attachment to. I just pulled it out to experiment with the paper on the fins. Having it turn out as well as it has is nice and has resulted on it growing on me a little bit. I've even going to get off my lazy backside and see if I can come up with some decals for it.

I didn't realize the grab bag nature of the kit. That explains a lot.

 

[Buckaroo]

We had a build session today with a group of about 15 4-H kids and used Boids from a bulk box. Excellent quality parts! The core of each rocket is the same, but the nose cone and fins are all different. There was one that had Cherokee-D fins/nose cone that was awesome, and I think the kids like the fact that their rocket is different than anyone else's in the room. Most of them are coming out to the Music City Missile Club launch this Sat so we'll see how well they hold up.

You can buy these by the 100 for $470 which is a steal given the quality of the kit.

The only real drawback that I can see with this kit is that it comes with a standard Semroc 12" chute which is way more that this thing needs. A "C" motor and a little wind and it's gone. Good thing you can get em bulk

By the way John thanks for the nice build thread. :clap:

 

[JAL3]

We had a build session today with a group of about 15 4-H kids and used Boids from a bulk box. Excellent quality parts! The core of each rocket is the same, but the nose cone and fins are all different. There was one that had Cherokee-D fins/nose cone that was awesome, and I think the kids like the fact that their rocket is different than anyone else's in the room. Most of them are coming out to the Music City Missile Club launch this Sat so we'll see how well they hold up.

You can buy these by the 100 for $470 which is a steal given the quality of the kit.

The only real drawback that I can see with this kit is that it comes with a standard Semroc 12" chute which is way more that this thing needs. A "C" motor and a little wind and it's gone. Good thing you can get em bulk

By the way John thanks for the nice build thread. :clap:

I didn't know all this background on this bird, I mean boid. Thanks for the info and the kind words.

FWIW, mine did not come with a chute. It had a streamer instead.:neener:

 

[JAL3]

When the tape came off, it was looking good. The bleeds were insignificant and the colors worked together better than they ever did for UTSA. I decided to go ahead and try to make some decals.

 

[Buckaroo]

FWIW, mine did not come with a chute. It had a streamer instead.:neener:

Streamer makes more sense... I don't know the vintage of the bulk box we were using the other day,maybe they all come with streamer now, but then again you said you've had yours for a while so who knows? It's been raining hard all day/evening in Manchester, TN so I don't know if we'll see any Boids launched tomorrow.

The paint job looks nice John, I wouldn't have picked blue & orange to go together, but it seems to work. Good luck when it comes time to fly. I finally had to quit building min diameter (or near mid diameter) rockets, my eyes just couldn't keep track of them anymore, and I HATE losing rockets.

 

[JAL3]

Streamer makes more sense... I don't know the vintage of the bulk box we were using the other day,maybe they all come with streamer now, but then again you said you've had yours for a while so who knows? It's been raining hard all day/evening in Manchester, TN so I don't know if we'll see any Boids launched tomorrow.

The paint job looks nice John, I wouldn't have picked blue & orange to go together, but it seems to work. Good luck when it comes time to fly. I finally had to quit building min diameter (or near mid diameter) rockets, my eyes just couldn't keep track of them anymore, and I HATE losing rockets.

I would not have picked the combination either. I just happened to see these cans first when I was looking AND the "boid" connection to the UTSA Roadrunners hit me. That was my first engineering school and their colors are blue and orange.

I hate losing rockets too. For a while when I became a BAR, I was replacing almost everything with streamers.

 

[JAL3]

I located an image of the UTSA Roadrunner on the internet and downloaded it. Its different from what I remember.

 

[JAL3]

I opened the file in Photoshop and resized it to where I thought it would fit on the fins. I printed it out on a laser printer and found I was a bit too pessimistic on the size. From there, it was a simple matter of applying one decal to each side of each of the three fins. I also spaced three smaler ones around the nosecone.

 

[JAL3]

Its not fancy but I think the addition of a little decal dresses it up a bit. The rocket is ready for its maiden flight.

 

[JAL3]

My Boid was the first launch of the day when it went for its maiden flight. I loaded some dog barf and a 1/2A6-2 motor, mostly because I happened to have one sitting in front of me when I got through setting up the range. It took off nice and straight and, as expected, did not go very high. It probably could have coasted another second before ejection but all in all was a good maiden flight.

A video of the flight can be seen here: https://www.flickr.com/photos/23694991@N03/3517002072/

 

[JAL3]

The second flight was nothign less than spectacular. I loaded an A6-4. I announced the flight and the rocket took off and kept going. I had announced it as an A6-4 but was accused by some of having loaded a B and by others a C. It went way up there. On retrieving it, I made sure the rocket was visible the whole time and made a production of removing the motor in front of witnesses. It was indeed an A6-4. It was also an impressive flight.

A short video of the flight can be seen here: https://www.flickr.com/photos/23694991@N03/3517003644/

Its not very long because I cut it off when I lost sight of the rocket.