The Apogee Saturn V is a 1/70th scale model of the magnificent NASA Saturn V moon rocket. A companion kit to the Apogee Saturn 1B, this is a large rocket standing over 62 inches tall and 5.6 inches in diameter. The large size and high level of detailing make this an impressive rocket. I've built two Apogee Saturn V’s - one a ‘flyer’, the other a display model which is destined for the "Man in Space" exhibit at the Seattle Museum of Flight. This review reflects the combined experiences from building both Apogee Saturn V models.
The Saturn V kit can be ordered directly from the Apogee web site (or if you prefer, by phone, fax, or snail mail). All parts were present and accounted for when my kits arrived, however, on the first kit the shipper apparently got the box wet and some of the parts suffered water damage. Apogee owner Tim Van Milligan was very helpful in obtaining replacements for the water damaged parts.
This is a complex kit and the parts list reflects that. In addition to the huge main body tube (35.4" long x 5.6" diameter), there are three other body tubes, four coupler tubes, 8 sheets of vacu-form parts, two die cut balsa sheets, 3 balsa half-round dowels, several sheets of printed or embossed wraps, a plastic Apollo capsule kit, a bag of cast resin fins and detail parts, another bag of five injection molded plastic F1 engine display nozzles, two nylon parachutes, 2 Kevlar® shock cords, clay nose weight, a decal sheet, some miscellaneous parts, and a CD-ROM of instructions.
As noted, the instructions are contained on a CD-ROM, in PDF format. You'll need Adobe Acrobat Reader (to open the instructions file) and QuickTime (to view the video instructions). If you don't already have Acrobat and/or QuickTime, download instructions are included on the CD.
The video instructions are very good and informative but have some faults. First, they are somewhat time consuming--there are four hours of the video instructions and they can be occasionally tedious. This was definitely the case while building the second Saturn. Since I'd already built one, I basically knew how the kit went together--I just needed a quick reminder of the details and sitting through the entire videos got old fast. Further, it can be difficult to find a specific step in the instructions (e.g. to double check something) so an index would be helpful. It would also be nice if in the step where you add the nose ballast, it told you where the flight prepped CG should be, as it is you need to go to the (included) RockSim simulation to find the CG and CP data (this may have contributed to the CG problem I experienced). I found that at least on my computers, the video instructions ran somewhat better if I downloaded the entire folder onto the computer (rather than running it directly from the CD). I also ended up just putting my old laptop next to the workbench so that the instructions were available in 'real time'. On the plus side, this rocket is a complex, difficult, time consuming build, and the nicely detailed video instructions greatly improve the odds that you'll get it right. Also, although I'm an experienced model builder, I did learn some useful new tricks and techniques from the video instructions.
Another unusual aspect of the kit is that you need to 'make' the tube couplers. Although all the tubes are pre-cut to the correct length, the coupler tubes are the same diameter as the tubes they are intended to fit inside. It is necessary to cut and re-glue the tube couplers to get them to the proper slip-fit diameter. There are nicely detailed video instructions of this process, and it worked out quite nicely. Although having to make couplers may seem strange in a kit that retails for $225, most of the tubes used in this kit were custom manufactured to get the correct scale diameter. Being able to reduce the number of custom diameters needed helped Apogee keep the relatively low volume Saturn kits affordable.
The rocket is built as three major sections: the main 1st stage/2nd stage 'booster' section, the S-IVB 3rd stage (which includes the 2nd-3rd stage transition section), and the LEM Transition/Service Module with the Apollo Capsule. Most of the construction is fairly basic and straight forward, with the notable exception of those notorious vacu-form wraps. Due to the problems many people experience trying to use the thin CA technique for attaching the wraps, Apogee created instructions for using double sided tape to attach the wraps (some early instruction CDs lack these instructions, if necessary you can find them at http://www.apogeerockets.com/education/newsletter71.asp). I figured I'm an experienced model builder and I could make the CA work. Wrong, at least on my first try. Where the wrap was simple and straight (such as the first stage Inter-tank wrap or the third stage wraps), the thin CA technique worked reasonably well. However, where the wrap had multiple protrusions along the edges (the first stage thrust structure wrap and interstage wrap), it was an entirely different story. The protrusions simply don't want to adhere to the body tube. If you get a bit too much CA on the protrusion and then try to use your finger to hold it to the body tube, you'll glue your finger to the wrap (I found it quite interesting how much better CA seemed to adhere to my finger than to the body tube). On my first Saturn, I managed to do an OK job on the thrust structure wrap, but I seriously botched the interstage wrap to the point there was no way I was going to get it right. I was so disgusted that the nearly completed Saturn V sat on the corner of my workbench for 3 months before I finally decided to rip off the interstage wrap, order a replacement wrap from Apogee, and try again. The replacement wrap went on much better and all was well with world until I started painting. In the course of priming and sanding, I accidentally crushed one of the interstage wrap ullage motors. As this is rather easy to do, the instructions include a step on how to repair this type of damage using epoxy clay. The repair technique worked well until I sprayed the next coat of primer. Apparently I did not seal well around the repair and when the primer seeped underneath, it caused a large section of the wrap to melt. (Expletive deleted!) So I ordered another interstage wrap. This time I filled the ullage motor and external H2 line details with epoxy clay before attaching the wrap. At least with my previous practice this wrap went on relatively easily, allowing me to finally finish the model.
Apogee uses very thin plastic for the vacu-form wraps. This was done to help preserve a high level of detail on the wraps, but I think they may have overdone it. It is characteristic of vacu-forms that the plastic gets thinner when formed, especially around large details, and the resultant wraps can be extremely fragile (I literally had one wrap crack when I picked it up). Filling the large details with epoxy clay was a big help -- I recommend this step (it doesn't add much weight) - but there is a large amount of handling involved in building and painting this model, and even after filling the large wrap details with epoxy clay I still had problems with the interstage wrap splitting and tearing around the large details. Personally, I'd trade a little loss in surface detail for the increased durability and strength of a thicker plastic wrap.
Here are a few tips if you choose to use the thin CA method: instead of your finger, use a small steel ruler (or something similar) to hold down the wrap protrusions while applying the CA--the steel is far less apt to end up glued to the wrap (and if it does, it’s much easier and less painful to remove). When applying the CA, if a wrap protrusion doesn't adhere, don't keep applying more CA (it’s likely you already have too much). Use a piece of masking tape to tape the wrap protrusion down, and leave it alone to allow the CA to cure. Carefully remove the masking tape after 15 minutes or so -- usually the protrusion will be glued down. If not then try the CA again. Tim Van Milligan recently informed me that there is a new type of CA glue available that is specifically formulated for use on plastics and won't melt the wraps. I haven't been able to find the stuff yet, but if you can it is probably worth a try.
Painting and finishing of the Saturn V is also challenging. The video instructions have all the right steps and procedures for getting a good paint job, along with a multitude of detailed drawings and pictures showing the paint scheme and decal placement. But the bottom line is that this is a large rocket with a complex paint scheme, and getting it right takes lots of time, patience, skill, and perhaps a little luck. As I noted earlier, finishing tasks such as filling the body tube seams, priming, sanding, and masking off the roll patterns take a lot of handling of the rocket, and it is agonizingly easy to damage the wraps during all of this handling. The only defense is to use extraordinary care and maybe a soft towel or blanket to set the rocket on while working on it. On the plus side, the fins are removable (they are a simple friction fit into the fin-fairing) which simplifies the painting of the fins and fin-fairings. The kit includes decals for all the various Apollo/Saturn V flights. The water slide decals are very nice, and were easy to apply without tearing. A few finishing tips: Fine steel wool works better than sandpaper when finishing the corrugated wraps, and be sure to apply several coats of primer to the cast resin parts (e.g. the fins) to seal the resin and provide a proper paint surface before the color coat. Oh, and don't use Rustoleum primer on the wraps. Rustoleum is a fine primer, but the stuff hates plastic--I've actually had it melt a plastic nose cone. Those thin plastic wraps wouldn't stand a chance.
Construction Rating: 4 out of 5
While the kit does not include a list of recommended motors, such a list would be real short--Tim Van Milligan recommends the AeroTech G80-4T. However, as of this writing, G80-4T motors are in very short supply so I tried some alternatives using RockSim (if you don't already have RockSim, the instructions CD includes a demo version which is good enough for evaluating various engine options for the Saturn V). Realistically, the only other "standard" rocket motor that was suitable was a G64-4W RMS, and even that required an extended launch rod. This rocket is heavy, almost into high power territory. Apogee quotes 39 ounces (w/o engine), my flyer came in at 42 ounces, almost exactly 3 lbs flight prepped. I should note that the lower booster section of the display Saturn V came out nearly 3 ounces lighter than the flyer, so perhaps I got a little carried away with the epoxy clay and glue fillets on the flyer. At any rate, there are only a few acceptable mid-power engines for the Saturn V. Someone who has a high power certification might want to consider modifying the engine mount to accept 38mm motors.
It took the better part of a year for me to build up the nerve to actually fly my Saturn V (and to find a G80-4T engine). Although I provisioned my Saturn V for 29/240 motors, I don't yet have my Level 1 Certification (it’s on the "to do" list), so the maiden flight used the one G80-4T engine that I was able to find. RockSim said 470 feet and ejection 0.2 seconds after apogee, but the results didn't exactly live up to that. Initial liftoff was fine, but up and away the stability was marginal, and the Saturn V did a large, lazy corkscrew to an estimated 300 feet. Ejection occurred well past apogee and at a fairly high speed, at which time the upper and lower sections collided. The escape tower punched a hole in one of the booster fin-fairings before breaking off, while the two parachutes became entangled with the rocket body and only partially opened. Fortunately the partially deployed chutes provided enough drag to slow the tangled mess and overall damage was minor. Aside from the hole in one fin-fairing and broken escape tower, one fin was broken off, and all the OMS units were lost from the service module. Concerned over the apparent marginal stability, I did a quick CG check after I'd completed repairs. Lo and behold, the CG was a full two inches aft of where it should have been. With the long delay between when I finished the Saturn V and its maiden flight, I don't remember enough about adding the nose ballast to figure out how I fouled it up, but at least adding some more nose ballast to get the right CG was an easy fix.
For the second flight I was unable to find any G80-4T motors, so I decided go with a G64-4W RMS. RockSim predicted 475 feet and ejection 0.4 seconds after apogee, however of greater concern was that RockSim did not predict stable flight until 84 inches after liftoff. Fortunately, six foot long launch rods were available, so I thought I'd give it a try. The result was magnificent. Apparently the extra nose ballast did the trick, since the flight was near arrow straight, with the Saturn making a bit of a tail slide at apogee before the ejection fired. Once again, there was contact between the sections as the parachutes deployed, but this time contact was slight and the chutes deployed beautifully. I actually think the G64-4W RMS is a better match for this Saturn V--it simply looked and sounded more impressive than it did on the G80-4T (as long as you have a long launch rod available).
Recovery is by two large nylon parachutes, with the ejection break at the 2nd stage/3rd stage transition. The lower main section uses a massive 60" octagon parachute, attached by a short Kevlar® shock cord. The upper portion makes use of 36" hexagon parachute, attached by a Kevlar® harness that holds the Apollo and 3rd stage horizontal (to help protect the relatively fragile escape tower from damage on touchdown). The parachutes are generously sized for the weight of the rocket -- note that on the maiden flight landing damage was minimal even though the parachutes never fully deployed.
Flight Rating: 5 out of 5
Overall, this is an absolutely spectacular model of the Apollo Saturn V moon rocket, but it is not for everyone. I've built a lot of rockets (including over a dozen of the various iterations of the Estes 1/100 scale Saturn V), and this is far and away the most difficult rocket kit I've ever built. A fellow Northwest rocketeer joked that he spent 1000 hours building his Apogee Saturn V, and while that number is certainly excessive, I'm sure I spent well over 100 hours building each of my Apogee Saturn Vs. But if you are prepared for a challenging build, this Saturn V has a jaw-dropping presence that is difficult to describe or explain. It looks magnificent and massive just standing there, and it simply dwarfs the Estes 1/100th scale Saturn V model, which isn't exactly a small rocket! While it is difficult to put so much time and effort at risk by flying this Saturn V, the result can be extremely rewarding, and even seductive. I expect my flyer to make regular appearances at our (recently re-opened) high power launch site.
Overall Rating: 5 out of 5