Just going through all the parts for this build before beginning! Quality components all around and the 3D printing on the nose cone is nothing short of AMAZING. Massive 5 ply Birch 1/4” Plywood through the wall fins, a triplet of 3 ply Birch 1/8” Plywood centering rings, massive thick walled LOC Precision 7.5” Body Tube, Thick walled 38mm MMT, heavy duty swivel, 38mm Motor Retainer, Eyebolt and Launch Button hardware, massive Kevlar shock cord, Nomex Chute Protector, a big blue pre-rigged nylon Parachute and nose weight all came in this awesome kit. The Minion goggles came from Amazon! Looks like a pretty straight forward heavy duty build! Follow along as I bring Minion Bob to life! All hail to KING BOB!
(PART 1 of pics)Today we got the official start on this kit! I did a dry fit of all the parts this time inside the tube. Everything was a great fit with no need to sand anything! Next I sanded the MMT glassine layer off and sanded the glue surface on the retainer. Then, using JB Weld high heat epoxy the retainer and bottom centering ring were glued on. This was set aside to cure. Next I drew a line up the BT for the rail button installation Galway between two fin slots. The hole locations were marked then I drilled pilot holes followed by a 3/16” bit. The holes were sanded on both sides of the tube and the Xacto knife was used to further clean up the hole. Next I mixed up some FixIt Epoxy Clay and installed both rail buttons. This was also set aside to cure. Finally I washed and sanded the inside tip of the NC in preparation for the nose weight. I wiped the glue area with alcohol first. My NC weighed just over 10 ounces to start. Using the included lead weights (all, but 2) along with the eyebolt anchor I added several batches of BSI 30 minute epoxy to bring the overall weight up to just a hair over 17 ounces total. This was too set aside to cure.
My KING BOB MINION rocket build today part deaux! I sanded down the huge nose cone with 60/120/220 grit sandpapers and then shot it with filler automotive primer. It’s been set aside to dry. Then I began prepping the four fins for their fiberglass treatment. I sanded all the hard corners off with special sanding blocks loaded with 60/120/220 grit sandpapers then went over both sides of each with 220 grit. They are now ready for fiberglass, but I don’t have that in me today.
Oh and I got some eyeballs ordered that should work great inside the goggles as well as a pair of cool little black shoes plus my wife is picking me up a kid’s Minions pillow figure that I think I can use to provide the arms and gloved hands!
Got a second wind after a few hours so I got side 1 of all the fins fiberglassed with medium weight cloth and West Systems 105 resin and 206 slow hardener applied neat.
Well this popped up in a private message from the owner of Front Range Rocket Recovery asking if I’d be interested in this custom parachute design for my Minion King Bob rocket. Of course I couldn’t refuse as he did such a wonderful job on my Warrior Prostate Cancer Awareness rocket (36” chute”) last year. The new one is a 48” nylon parachute!
My Minion King Bob rocket build log: this morning I trimmed off the excess fiberglass from last night’s glassing session then prepared to do the other side. I applied today’s fiberglass using the same method and everything is now set aside to cure. Next I filled all the spirals in the body tube with the Upol spot glazing putty and set that aside to dry. Finally, I prepped the nose cone by wiping it down with a paper towel and alcohol. Then I did another round of filler primer. Once that has dried I’ll wet sand. That’s all I can do for now until various parts dry.
My Minion King Bob build log: got the tube sanded down with 220/400 grit sandpaper. I also trimmed the excess fiberglass while the epoxy was still green. Finally I wet sanded the nose cone and shot another light to medium coat and set aside to dry.
My Minion King Bob rocket build log: the fins were sanded down post fiberglass/epoxy resin application and all slots where they meet were slightly filed to accept the additional thickness of the fiberglass layer. I then marked both sides of each fin to denote the tube line as no filler is needed beyond this point to the root. I then applied the Upol automotive spot glazing putty to one side. When that’s dry I’ll glaze the other side of each. Keep in mind most of this glazing will be sanded away and is meant to fill any of the fiberglass weave that wasn’t filled good enough by the epoxy resin. I decided it was easier to basically get the fins to a pre-primer ready state before gluing them in permanently. More to come later today I’m sure.
Decided to fix a heartburn issue and get the file out again. Most nosecone shoulder to outer diameter transitions are made at 90 degrees so the nosecone will sit flush on top of the tube with very little noticeable seam visible. This nose cone had a concave transition which prevented a flush fit so with the file I removed enough material to get as close to 90 degrees as possible. It fits much better now and when it’s all painted it will be within acceptable parameters. This nosecone shoulder is also quite loose in the tube and will require at least a couple rounds of masking tape to secure for flight.
Today’s update shot from Steve at Front Range Rocket Recovery on my custom 48” Minions King Bob Parachute! I love this as it represents what a Minion looks like looking down from overhead!
My KING BOB’S MINION rocket build: today the fins were sanded down from yesterday’s glazing fill. Next I did a dry fit of the four with the motor mount in place just to make sure everything looks as it should. The fins were removed and a bead of glue was placed around the inside bottom of the tube being careful not to get any glue in the fin slots as they (fins) need to be removed after this glue has tack set. The motor mount was then seated into place with the fins temporarily installed for alignment. I seated the motor mount plate to be flush with the bottom notch of the fins and set it all aside to tack up. I used Tight Bond III instead of II because it has a working time of ten minutes instead of five. This extra time was needed to get everything positioned properly. I’ll pull the fins shortly and set this aside to dry overnight.
My KING BOB MINION rocket build log: this morning I tack glued in all fins with CA Gel then got to mixing up several batches of West Systems 105 epoxy resin, 206 hardener and 406 colloidal filler for all the internal fillets. Once that was done I did a glue fillet on the very bottom of the rocket with Tight Bond II. Setting this aside for awhile to cure up and then I’ll install the fore centering ring to the engine mount and tube.
My custom 48” Rip Stop Nylon Parachute from Front Range Rocket Recovery is done and being shipped today! Thank you Steve for an awesome addition to my KING BOB MINION rocket project!
My KING BOB MINION rocket build log: things arrived in the mail today! Bob’s royal cape and crown arrived along with materials for his 3D eyeballs! I removed some hair clips from the bottom of the crown. Since the bottom was flat I glued a small piece of cardboard ring to the bottom of the crown so that it will fit Bob’s head. Lorrena picked me up some furry material to glue to the cardboard ring on the crown. Then it was on to figuring out the eyeballs. Through examining, pulling and tugging on the goggles I found I could disassemble them into component parts, making the eyeball installation really easy from the front side. I made a plate from thin plastic that will eventually be glued to the inside of each goggle. Glued to those plates are the eyeballs (1.75” replacement hard plastic kid’s balls from Amazon). I basically just used half of each and they will be painted correctly of course in the near future. I’ll also be painting the goggles so those parts were sanded down in preparation for primer. Finally it was back to the tube and I permanently glued in the second motor mount centering ring with more West Systems. More internal fillets were done on that and I used wood glue to fillet this ring to the cardboard motor tube.
My KING BOB MINION rocket build log: for the appropriate glue location inside the tube for the final centering ring I placed a small ruler that sat level on the MMT to get a horizontal line. I then subtracted the thickness of the ruler and made appropriate marks around the inside denoting the top of the MMT. I then made lower marks one-half inch down from this. In between the prior two marks is the glue location. Next I tied the Kevlar shock cord around the MMT initially with a slip knot followed by two square knots and glued in place. The shock cord was then run through the top centering ring. Glue was applied to the marked areas in the tube and around the top half inch of the MMT. I then ran all the loose shock cord down the MMT to get it out of the way while seating the centering ring. It took a little nudging to get it seated, but I got it close by hand. I used a large diameter piece of doweling and a hammer to gently tap around the centering ring to get it to its final position about a 1/2” down the MMT. A glue fillet was then applied on both centering joints and set aside to dry.
My KING BOB MINION rocket build: while the rocket dries I moved onto embellishing the Royal Crown with a furry bottom and adding multi-colored multi-faceted jewels and a base plate with a suction cup. I’m really happy with how it turned out! I had to drill holes in the backside of the eye plates to allow air to flow in as the glue on the inside hadn’t dried from yesterday. That did the trick so I did some further fitting of them into the goggles. Those are all ready to primer now when the weather improves. With the glue on the rocket set up more than enough I’ve got it marked out with pencil for the 1/2” fin fillets and taped off. I’ll do the fillets after dinner and update.
My KING BOB MINION rocket build log: using West Systems 105 epoxy resin, 206 slow hardener and 406 colloidal filler all mixed to a peanut butter texture the fin fillets were applied. I let the fillets set up for about 45-60 minutes and then using a large socket bathed in alcohol I pre-formed the fillets. Then with a mixing stick I removed the excess epoxy from all the adjacent tape and then carefully removed all the tape in the reverse order of how it was placed. I’ve set the rocket aside for the fillet epoxy to cure overnight. Tomorrow I’ll sand the fillets and touch up with automotive glazing putty if necessary and prepare the area for primer.
My KING BOB MINION rocket build log: tonight I got the epoxy fillets sanded down and applied the next round of automotive glazing putty for round two on the fillets.
My KING BOB MINION rocket build log: today I sanded down the fin fillets from the glazing putty applied yesterday then put another top coat on, let dry and final sanded. The fillets are now complete. The weather was ok for primering a few things like Bob’s eyeballs and the goggle parts. I let those dry and then made a centerline on the front of the rocket body in order to correctly position the main goggle part. I mixed up some BSI 30 minute epoxy and glued the goggles permanently to the body tube. I also did some glazing putty fill work on the very bottom of the rocket because even the bottoms of rockets need love too! OH AND MAIL CALL FROM FRONT RANGE ROCKET RECOVERY! The parachute is just beautiful!
