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Robert Koenn


Astrobee1500-recruit booster-ST20 scale
RJKoenn53 That is great and I will probably be building up an Astrobee in the future. Do you plan on a fin unit. Here is a pic of my NARAM winning scale model built from scratch about 12 years ago.
Astrobee1500-nose cone for ST-20 tube
RJKoenn53 Are there any plans for printing a fin unit for this as well? I know it would be a bit costly but it would go great with the nose section. I've built two large scale scratch built Astrobees and also Always BT-60 size kit.
Arcas Fin Unit for BT-60 and 18mm motors
RJKoenn53 Is there a 3D printed Arcas scale nose cone available for the BT-60 tube as well?
Pershing 1 BT80-2nd Stage Fin Unit for 24mm motors
RJKoenn53 Is there a nose cone available for use with your fin units?
RJKoenn53 commented on V-2 Fin Unit BT55 for 18mm motors by kcespedes
February 22, 2016
V-2 Fin Unit BT55 for 18mm motors
RJKoenn53 Another great product from Kevin. I have built four model rockets from his parts and they are excellent. Here is a picture of the V2 using this fin unit and his nose cone.
Redstone Booster Fin Unit ST-20 for 18mm motors
RJKoenn53 @ccorway Mine has flown and there was no stability issues. You need to extend the engine mount tube down to the bottom of the fin unit. You will also need to cut off the main body tube a piece equal to the length of the fin unit. One thing I would recommend though from my first flight with it at NSL in SC. It flew fine but the booster chute did not open too good so it hit rather hard on the ground that was almost like concrete. The impact broke all the little, discrete struts and it now wobbles on the body. I would recommend putting a tight coupler tube inside the fin unit between the two sections so that if it hits hard it has something to prevent damage. I am going to have to remove the aft section at that joint, put some small plastic rods in to replace the broken ones, and put in a coupler tube.
RJKoenn53 I presume the OD is to match the 2.05" tube the kit is based on? This is going to make me purchase one of those kits and build it even though I've rather given up flying model rockets due to foot neuropathy.
Hold Down Struts Airfix 1:144- 4 Pack
RJKoenn53 I just got these a couple of weeks ago for my Airfix Saturn 1B build. I had asked Michael about making these hold down struts and he did in about 24 hours. I took them out today and fit checked them to the bottom of the 1B fins and they are GREAT. I don't think I am even going to cut the base off as it is so thin it is barely noticeable on the fin and provides a much better mount than the strut surfaces by themselves. Thanks so much Michael, I bought some other parts for the build and this will greatly enhance it.
Honest John M31 Fin unit BT50 for 18mm motors
RJKoenn53 I used this fin unit and spin rockets from Mr. Espedes with the Estes Mini Honest John kit and it makes a great rocket. I still have to simulate the missing launch mounts and such but this is far superior to the kit fins built from scratch.
Little Joe ll (QTV) Fin Unit BT-70 for 18mm motors
RJKoenn53 I just completed a Little Joe 2 based on this piece and the capsule and LES from Aerobotix as well. It makes for a great model and I can say that with authority as I built a couple of the Estes kits back in the '70s.
Little Joe Capsule Langley Prototype BT 70
RJKoenn53 I had always wanted to build a Little Joe 1 flying rocket and Kevin's capsule and fin unit made it possible. They are great parts and make building the LJ1 fairly simple as you can see in the pictures of my finished model. I flew it for the first time at NSL 2015 and it flew perfectly straight and stable with a B6-4.
Honest John (M-50) Fin Unit BT55 - 24mm motors
RJKoenn53 Kevin, I believe this should be the "Little" John and not the Honest John.
RJKoenn53 Do you have an Honest John nose cone available to go with this fin unit?
Little Joe ll Nose Cone (QTV) BT-70 Pt1
RJKoenn53 @kcespedesThanks, I went through all the pages kind of carefully but missed it. I'll be picking up the LJ2 parts in the near future sometime. So far I have bought parts from you for 5 rockets. I was going to give up rocketry due to mobility issues but you got me to at least build some smaller BP scale models again. Thanks, I'll be keeping an eye out for future products. How about the nose and adapter for a Thor Agena B?
RJKoenn53 Is there going to be a part 2 with the LES rocket?
RJKoenn53 commented on Thor Agena B-Nozzle by kcespedes
April 10, 2015
Thor Agena B-Nozzle
RJKoenn53 Is this for a BT-55 tube as would be used to build a copy of the '60s Thor-Agena B kit?
Little Joe Fin Unit BT70 for 18mm motors
RJKoenn53 Combining this with your Mercury boilerplate capsule and escape tower can a BT-70 based Little Joe 1 be constructed then? If so I am buying the set as that vehicle has always been very cool. Any considerations to BT-70 size Little Joe 2 parts?
   Fin Unit T35 Nike Apache for 18mm motors
RJKoenn53 What diameter body tube does this mate with?


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