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Sport Rocketry / Rocketry Products / Estes / Kits / Saturn 1B / 7251 (2020)

     Rocketry Product: Estes - Saturn 1B {Kit} (7251) [2020-]

    Estes Saturn 1B, #7251 Build, Part 1, Parts (2020-11-27)
    The 1/100 scale Saturn 1B has arrived - A perfect shelf companion to the 1/100 Saturn V. Here's the front and back of the kit box. Notice the white Redstone tanks at the bottom, this is the Skylab ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 2, More Parts (2020-11-28)
    For me, this part is the highlight of the kit. I've built a few Saturn 1Bs over the years, the scalloped shroud has always been a difficult construction step. In the old Estes 1/70 scale version, it ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 3, Tube Seam Fill (2020-11-29)
    I'd recommend filling the tube seams before assembly. It is difficult to fill the seams after they are glued in place. The eight booster tubes end up too close together to reach the seams. With the ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 4, Engine Mount (2020-12-01)
    There will be some posted steps that might seem out of order from the instruction sheet sequence.  I tend to prep some parts before they come up in the assembly steps.     Here's all ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 5, Engine Mount Finish & Fin Prep (2020-12-02)
    TIP: If you place the centering rings as shown in the instructions, you might add a drop of glue over the top of the engine hook bend slit. This is an "old school" thing, seen on instructions in the ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 6, Fuel Body Tubes Primer/Filler (2020-12-03)
    I did dry fit the fuel tubes in scalloped tank shroud. This is one of the best new parts in the kit! A very good fit. The eight fuel tubes needed a shot of Duplicolor Filler/Primer after the CWF was ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 7, Fitting Low Wrap (2020-12-04)
    The instructions say to trim off the bottom of the lower, narrower wrap to 1/32" below the corrugations. The top picture is the before - I've marked the 1/32" cut with pencil lines. Below is after ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 8, Adhering Low Wrap (2020-12-05)
    The 3M 77 adhesive will hold the wrap down, but the joint seams can lift. I squeezed a drop of medium CA glue onto some scrap cardboard. A toothpick was dipped into the CA glue and transferred, ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 9, Tower Assembly (2020-12-06)
    I'm not building in the order of the instructions. I'll be bouncing around a bit -      One side of the tower has alignment pins, The other side has alignment holes the pins fit in. ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 10, Tower Nozzles & Clay Weight (2020-12-07)
    The escape tower nozzles were slipped together. Liquid glue was brushed over the top of the "X" joint. Two clay weight "pats" are included in the kit. Together they weighed just over 1/2 oz. The ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 11, Fitting The Larger Middle Wrap (2020-12-08)
    TIP: Tape down the wrap before doing any straight edge trimming. You don't want it to slip under the straightedge and end up with a bad cut. When cutting the thin vacu-form wraps, it's not necessary ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 12, Upper Wrap GOTCHA! (2020-12-09)
    GOTCHA: After the middle wrap is in place - Don't immediately adhere the upper wrap using the single pencil line drawn down the body tube. On my two builds, I found the longer tunnel would not ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 13, RCS Nozzles - Little GOTCHA! (2020-12-10)
    Jumping around and jumping ahead -  Don't cut the wire anchor slot yet - more on that later. This post is just for the RCS nozzles. Drilling by spinning a knife blade tip will make the holes ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 14, Display Engines (2020-12-11)
    Before gluing the nozzle spacer tube onto the low plate -  These can be hard to center accurately. Center it visually, then trace around with a pencil. Check to see if the circle tracing is ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 15, Wire Anchor Slot, Part A (2020-12-12)
    This is one of the trickier parts of the build, bending and inserting the wire anchor. The upper section parachute will clip to this anchor for recovery. You are supplied with a length of brass ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 16, Wire Anchor Slot, Part B (2020-12-13)
    Okay - Here's a weird one -  Instead of leaving an open slot after the wire is glued in, I cut a thin vertical hinge in the body tube. Think of the slot as having two sides. One side of the ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 17, Fill Anchor Slot & Prep RCS Nozzles (2020-12-14)
    The wire anchor slot needed a shot of filler/primer and smooth sanding. This tube had already been filled with CWF and shot with filler/primer. This was the final fill. I did mask around the anchor ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 18, Tunnel Mask & Capsule Tower Paint (2020-12-15)
    The Antennas have raised vertical yellow bars. I wasn't sure about masking these, they would be a bear to hand paint. I figured I'd try to Scotch tape mask them Scotch tape is set on a plexiglass, ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 20, Gluing On All The Booster Tubes (2020-12-17)
    Jumping around again: The centering ring with the small hole in it is glued even with the bottom of the core body tube. That small hole designates it goes on the bottom.  TIP: Don't make you ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 21, Starting The Black Color Mask (2020-12-18)
    The main upper body was spray painted gloss white. Three coats of paint, lightly sanding between coats 1 and 2.     Masking over corrugations isn't easy. I wish I could take credit for this ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 22, Outlining The Mid Section (2020-12-19)
    The Ultra Fine Point Sharpie end nibs appear to dry out quickly. Keep a piece of paper handy to get the ink flowing again. The picture shows many scribbles from restarting the ink flow when ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 23, Spraying The Mid Section Tube (2020-12-20)
    On the left is the mid section mask after the gloss black is sprayed. The tape was set down the middle of the wide Sharpie ink outlines. I used a combination of brown masking tape and grocery bags ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 24, Outline Lower Body (2020-12-22)
    The four painting pictures can be confusing.  TIP:  It's not mentioned in the instructions - starting from the left side, every picture (going to the right) is a quarter turn of the model. ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 25, Painting Lower Body & Gluing RCS Nozzles (2020-12-23)
    The black areas on the lower body has been outlined.  Notice the interior surfaces have been masked. If paint got on the inside of the scalloped shroud, it might drag and mark the white tubes ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 26, Masking & Painting The Fins (2020-12-24)
    I used the height of the black/white body separation line to draw a mask line on the fin sides. I stacked some CD cases to get close to the correct height. A piece of cardboard between the cases got ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 27, Painting The Fins, Outside Edge Color Separations (2020-12-25)
    TIP: When the tape on the leading edge tape was lifted, the paint line was rough. A Mister Clean Magic Sponge was wetted and wrung out. Wipe a Q-tip on the damp sponge, picking up some of the ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 28, Engine Hook Notch (2020-12-26)
    A notch is needed in the low centering ring to allow engine hook movement. The notch location is set between two of the booster tubes. Slide the engine mount in place and mark the width of the hook ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 29, Scalloped Fairing & Centering Rings (2020-12-27)
    I applied a small fillet and removed the excess with a Q-tip. You don't want the glue to get in the way of the centering ring position. You can use a little more glue on the bottom ring. The ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 30, Command Module Mask & Shroud Line Harness (2020-12-28)
    It isn't pictured here, but I did do quite a bit of touchup to the white and black mask areas. I'll add 20 minutes time below for the touchups.     The umbilical is painted silver. I used ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 31, Gluing On The Fins (2020-12-29)
    Most builders would glue on the fins in order of the instructions, mask and paint afterwards. I thought this would be too difficult especially in the tight fin root areas. This is why I painted the ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 33, More Decals (2020-12-31)
    I understand these are "camera focus" markers.  They are tiny! You don't want to be fishing these off the bottom of your decal soaking dish.  TIPS:  Your soak water shouldn't be deep. ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 34, Antenna Gluing (2021-01-01)
    I still have a paper wrap around the body for protection while handling. The antennas are set to the side of the glue area and a pencil line is drawn. Do the same on the right side - draw a line ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 35, Upper Shock Cord Sling, Glue Sections Together (2021-01-02)
    GOTCHA : You are supplied with a long piece of shroud line to tie up the upper body recovery harness. Try to break the string with a tug - I found mine too weak to be trusted with a strong ejection ... [Read More]

    Estes Saturn 1B, #7251 Build, Part 36, Shock Cord & Launch Lugs (2021-01-03)
    A standard tri-fold mount is to the shock cord and  the 18" chute on the lower body. TIP : With a pencil, mark the shock cord 2" from the top of the tri-fold mount. Use the pencil mark as a ... [Read More]

    Estes Saturn 1B, #7251 Build, Finished (2021-01-04)
    This one was a good build adventure. There have many improvements over the original 1/100 scale Centuri kit format. It took a little over 28 hours to assemble and paint. Most builders would glue on ... [Read More]

    Estes Saturn 1B Paint Patterns (2021-01-08)
    Here's some detailed four sided views of the Saturn 1B. This is for the SA-205 version, with the alternating black and white tanks. Still a good reference, courtesy of Apogee: CLICK HERE Note ... [Read More]