My Maple Seed disaster

The Thrifty Rocketeer continues... (in the Spring of the virus)


So, many of us Rocketeers rejoiced at the requirement to Stay at Home and out-last the ravages of the Covid-19 virus.    We could start in on our build pile, and very few objections would be filed.


So each of us chose the most appealing build.  I chose the "Maple Seed" by Semroc, marketed by eRockets.biz

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I must admit, the package was smaller than I had expected.  And I assumed the design for maple seed fins that are shed at apogee was simpler than I expected.

I was wrong.


First, there are a fair number of stamped parts that get sandwiched together to make up those fins. Second, the fins need to be tuned, or balanced.  Third, a great deal of design has gone into this.  It's not surprising that it's been judged a Skill Level Three kit.


And I thought I might knock it out in a night.  Wrong again.

And by rushing, I made a critical error.  Not once, but three times, as I tried to get ahead on the timeline.

 I should say that it's my own fault. Upon re-reading the instructions, there are at least 3 indications that  might have warned me that I was flipped from where I should be. I think there should be another in bold red at the critical step: "DO NOT GLUE THE SECOND TURBOLATOR ON THE OTHER SIDE!"


But there's something else that I noticed. The parts list indicates two washers for the nosecone weight, trapped between the eye-bolt and the balsa nosecone. I found only one, heavy, thick washer.  I assumed that someone went with a heavier washer and just eliminated the second.  (I found after checking with eRockets, that this was NOT the case. I appear to be missing one.  They asked if I had an extra one laying around the house... as It's not worth the postage to ship one.)


I also have found the designer/developer on line, and was able to ask several questions of him. There's no question that he's intimately acquainted with the kit, having taken the initial design and modified it significantly to completion.  I don't know  how many copies of the kit were initially produced, but I think interest is picking up as we get toward Spring.  You should pick one up!


Anyway, the designer answered several of my questions and was generous with his time. Yes, there are two types of glue called for. At only one point is the superglue (CA) specifically called for.  Apparently, it makes no difference which glue (yellow or CA) you use in the rest of the assembly.  The only issue becomes unneeded weight.  I would suggest wood glue on balsa.


Second, he confirmed that I was missing a washer and has offered to send it to me, along with a few replacement parts.   In my screw-up, I glued a thin turbolator onto the wrong side of the fin with CA.   I was able to pry it off with the gentle use of a wood chisel, but in the process, the thin shaft curled into a wood shaving. It is totally unusable. However, the CA either didn't penetrate as much as I had expected, or didn't coat completely, allowing me some purchase to 'flake-off' much of the piece.   (Now, I should also comment that the resulting scar on the wrong side is quite a blemish, and so I was planning on a thin layer of spray paint to hide it.  The designer waived me off, saying paint was unnecessary and would add weight. He didn't recommend it.)


He also suggested that the original "first flight" C11-3 motor, was the only one he recommended.  Someone else has added D12-3 to the list, which he doesn't recommend.  I will take him at his word, looking for a package of C11-3 motors once this Stay-At-Home order is lifted.


And finally, as I attempted to balance the rocket as a whole, I was supposed to insert a D12-3 into the motor mount.  Unfortunately, all I have is a D12-5, which I think will give me similar results. The launch lug, which is being positioned, is long...and I think will allow a lot of error.


To recover from my error, I am cutting a 3-part replacement piece from scrap balsa, and will use  wood glue to both glue it together and in place. I can trim it to fit over the first turbulator.  And I believe with the additional clay used to tune the fin, it should work.  However, I am going with a thin layer of spray paint, both to hide my scars, and also for my own design sense. ( More on that later.)


It is entirely possible that I will remake 3 seed fins from scratch in the near future, and so, I am not terribly worried if my paint job will ruin this set.   Remember, the designer anticipated that a fin could be lost as the seeds twirl to the ground.  As a result, they have packaged up a replacement fin kit that runs about $11.99 each.  That's a little hefty, in my opinion, but I haven't ever developed, assembled and marketed a kit from scratch...and so I'm not going to comment. In my case, having to replace 3 fins due to my own error would run me MORE than the original kit cost.  But I suspect they never anticipated that anyone would be as dumb as I was.


I also need to add that I have had two offers to help me recover, both in terms of selling me a drastically reduced-price original kit... (Thank you friends!) ... but also a rocketeer has offered to cut from his balsa sheet the replacement parts that I need. (*thanks to my second friend as well)  Never let it be said that rocketeers are not generous and also very willing to help each other out.


Now that I have confessed my sins up front, let me assure you that I intend on starting a build-thread with photos next installment.  Due to problems with my operating system and incompatibility of photos, this may be a challenge, but I am working toward beginning shortly.


Until then, keep your glue capped and save your balsa scraps!  I NEEDED MINE TODAY!

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