Semroc Micron Build 6

Good morning. I’m off today so I’m going to spend a lot of time trying to finish this little rocket. I really like it, although the end result of my epoxy putty fillets is pretty, well, ugly. See below for more.

I decided to actually look down the forward end of the rocket to see exactly where the thrust ring ended up. As you can clearly see, it’s cockeyed in the tube. And it’s wedged and glued in permanently. I tried pulling it back out from the top using the Kevlar cord but it’s not going anywhere.

Looking closely below, you can see what resembles a little cord running below the surface of the body tube. My theory now is that when I started to insert the thrust ring, a bit of the Kevlar cord which was tied around the ring got trapped between the ring and the body tube wall. I think this point is when I started to feel the resistance as I was inserting the ring. Then the cord continued to work its way up along the thrust ring as I pounded the assembly with a dowel to try & get the ring to move. All this did was mess up the outside of the rocket and create a weird bulge in it, though I’m confident the thrust ring will hold up to any launch. The issue, as previously mentioned, now may be the CG/CP relationship.

For my next trick, I chose to mount the launch lug. Is that an easy task? Simply make a mark 1” from the aft end of the tube, slap some glue on the lug and place it, making sure it’s aligned? With little to no chance of further messing up the finish? Why, no!

 Here’s the glue I chose for gluing the lug on, Titebond Quick & Thick. It is supposed to dry quickly and strong, and supposedly won’t bubble when you fillet the launch lug. Here’s a shot of the lug just after gluing it on.

 Then after about 10 minutes, I realized that the cool checkerboard decal would cover up the lug if I applied it! I quickly removed the lug, deciding to paint the rocket first, then add the decal and then attach the launch lug. So the residual glue from the lug now adds to my rocket’s messed-up finish, and when I finally glue the lug on I’ll have to cut away and scrape paint away from the area on the body to be glued. So the remainder of this project is positively fraught with all kinds of potential to mess things up still more.

This is horribly out of order but I wanted to show some more fin fillet detail. The examples below admittedly look horrible. The right side was where I initially applied the fillets; the left side is after I started to attenuate the size of the little rolls I was making. I think after a few more rockets I could become good at this technique but I plan on sticking to good old wood glue for fin fillets, until I build my AeroTech Mirage, a HP bird that probably deserves epoxy fillets. If memory serves, a finger dipped in isopropyl alcohol is ideal for smoothing and feathering out the fillets so I’ll try to remember that with the Mirage.

So, this little bird is finished, except for my traditional nemesis : painting the thing.

Someday I swear I’ll get a photograph of the Micron that’s straight lol.