Here is a quick update of the SA-5 progress. I glued on the antennas, the umbilical door, and the hydrogen vent pipes. The umbilical door is cut from .005 sheet stock while the antennas are cut from some strip stock I had that looked close. The hydrogen vent pipes look a bit different that the last update. I added the short straight section after the bend at the top of the pipes. I at first thought I could leave it off, but the more I looked at it the more I knew that the short sections needed to be added.
The bottom of the vent pipes needed to have a slit cut into them so they could fit over the stub fins. Also note that I have glued the fairings back on the base of the vehicle.
Here are a couple of pics of the stub fins dry fitted to the hydrogen vent pipes. Note in the pic on the left that I have also drilled the vent holes in the tops of the fuel and LOX tanks. The pics also show the LOX and fuel fill and drain ports.
I also fashioned some hydrogen vents for the stub fins that will be glued on later.
I have also filled the areas on the inboard nozzles where Airfix had molded in for the turbopump exhausts. The inboards on the Block II vehicles exhausted their turbopumps out the sides of the boat tail in aerodynamic ports which are not yet installed. The outboards will require some modifications to look more like the real thing. The inboards need some extra details as well, they were not simple curved bells.
Back to work on the SA-5 model a bit. Work continues on the S-I first stage. I got the puttying and trimming on the tanks done and they should be pretty smooth. I scratch built the gaseous hydrogen vent pipes that go down the first stage at three points. There was plastic rod included in the conversion kit but they did not include the bend at the top that was required to make the pipes meet their counterparts from the S-IV second stage. I had some Evergreen plastic tubes that were a close match to the diameter supplied in the conversion kit. I cut them to length and then cut a small section from the top at around a 30 degree angle. Then I rotated it and glued it back on the tubing. Then I needed to trim the back side of the angled section since the Airfix kit does not provide enough room. I then taped them to the side of the S-I to see how they looked. I think they will be fine.
Before I glue the hydrogen vent pipes in place I needed to add more details to the S-I. I cut some narrow rectangles of 0.005 inch sheet stock to represent the antenna mount points and glued them in place at each quadrant position. I also added the electrical conduits that run down the side of each RP-1 tank from the antenna mount to near the bottom of the tank at the boat tail. I still need to add the antennas, the LOX and RP-1 fill and drain ports at two places, and also the LOX and RP-1 vent holes at the top of the tanks.
In concert with the S-I hydrogen vent pipes I also removed the vent pipes from the interstage. They are mounted too close to the sides of the interstage and would end up not lining up well with the pipes on the S-I. I debated with myself about doing this since it will require more scratch building, but I just couldn’t let that one go.
Speaking of not letting things go, I also removed the fairings from the base of the S-I stage. They were just too clunky with the blocky attachment points. So I removed them and will glue them back on after trimming all the excess plastic off. This also allows me to move the heat shield down to the bottom of the S-I instead of being slightly recessed.
After removing the hydrogen vent pipes from the interstage I stacked the S-IV on it to see how they fit. I knew that the S-IV was out of round but I didn’t know it was quite so far off. I’ll have to do a good amount of work to get them to fit like they should.
Finally, I cleaned up all the fins and then adjusted them to fit on the base of the vehicle. Each one was different in some minor way and the Airfix base was not quite as symmetrical as it looks. Some of them also needed some putty to fill some irregularities. They are now properly aligned and I labeled each one so I would know where each one fits. They will go on after all the other details are complete.
This is just a quick update before I jump back to the Millennium Falcon. I was preparing to attach the fuel tank portion of the first stage to the thrust structure. As I’ve seen before when I did the SA-205 Apollo 7 Saturn IB model, the tanks don’t exactly line up well with the thrust structure. There is quite a step out nearly all the way around the stage that requires a considerable amount of clean up to get a proper looking stage. While I was messing around with it trying to get the best possible alignment, I noticed that if I rotated the tank portion a bit in one direction most of the tanks lined up much better. The only problem was that it wouldn’t stay that way and it also tended to try and pop the tank section open at the seam.
I decided to try and remove part of the alignment guides that are on the thrust structure, hoping that would allow me to slightly rotate the tanks into a better position. That seemed to work pretty good. The tanks are now attached and are just awaiting some sanding, carving and filling to make them look good. But since the tanks line up better it will be a much simpler job that it would otherwise have been. There is still one of the tanks that will require a lot of work, but it is just one tank and not almost all of them which would be the case otherwise.
I only highlight one of the guides in the pictures above but there are four of them around the thrust structure and they were all trimmed the same way.
That is it for now. I’ll set this aside for a while I tackle the decals on the Millennium Falcon.
Time for a progress report on the SA-5 build. I started on the aft structure of the first stage. I needed to drill a hole for a brass rod that would attach the model to the display base. I marked an X on the top of the part and put the heat shield on the bottom of the base. I then went to my drill press and drilled a hole through the top down through the heat shield on the bottom. I then inserted a length of brass tube through the top and down into the hole in the heat shield. I only pushed it through until it was flush with the outside of the heat shield. Then I applied epoxy to the portion of the tube sticking out of the top. When that had cured I removed the heat shield and then applied epoxy to the tube from the bottom side. Then I put the heat shield back on. Once that had cured I had a rod that was positively attached to the aft structure and would not move while I added weight. With the head shield removed, I put some BB’s in and then poured in epoxy to secure them. With that I was ready to start adding details to the aft section.
I then glued the halves of the tank section together and then removed the molded in antennas. Next I added some details to the heat shield. I scribed lines into the heat shield to match the pattern of SA-5. I filled four holes for the inboard engines that will not be used. The inboards did not have the turbo pump exhausts around the engine bells like the outboards did. I also added four small bits of styrene rod to represent the water quench disconnects. I then added the flame shields for the outboards by bending some insulated copper wire bent to the correct shape.
I then went back to the aft structure. I filled the ribbing that was molded in. It is in the wrong place and does not cover enough of the base. I sanded that smooth and applied a light coat of primer to make sure I had them filled properly. I created a pattern to allow me to get the stringers spaced properly. There are fourteen stringers between each fin, with a blank area surrounding each fin. With the pattern secured to the part, I started gluing the .020 x .020 styrene strips in line with my pattern. I had to cut out a bit around where the inboard turbo pump exhaust goes. After adding all the stringers, I sanded a slight taper into the leading edge of them. With that complete I created 8 access doors from .005 styrene sheet and sanded rounded corners into each one. I then made two umbilical doors out of the same .005 sheet styrene. I then marked all round the aft structure for the placement the doors. I glued them on with my Tenax cement.
That’s it for now. Much more work on the first stage to go.
Well I don’t usually overlap builds, but I knew I was going to have to wait a bit before I could get back to the Millennium Falcon. I started my next project which is another kit from Martin’s Models from the UK. This one is a conversion set that modifies an Airfix 1/144 Saturn IB into a Saturn I Block II SA-5. It was the first Saturn I flight to have a live S-IV second stage. I love that rocket. It has those great classic lines.
Again the resin parts are quite rough and some are out of round, but it will be a great starting point and should build into a nice model.
I started by removing the pour plugs from the parts and doing any necessary trimming to the resin parts. Next I started removing the fins from the thrust structure of the kit part. This time I would not be removing the fairings from the base part since SA-5 had these. When I used the Airfix kit to make the SA-205 Apollo 7 Saturn IB a few years ago, I had to remove them. For SA-5 I did have to remove part of the top of the parts that made up the first stage fuel tanks since SA-5 had only a very small flat section. In the picture you can see how much had to be removed. The part on the right has the extra plastic cut off while the part on the left has not been modified yet. You can also see how much the plastic had yellowed over the years. I bought this kit when Airfix re-released it in the 1990’s.
You’ll notice that I had to fill a couple of divots that I made when I was removing the fins. I got a bit zealous with the Dremel and created an oopsi moment.
Next, I moved on to some of the resin parts. The tapered interstage needed to be sanded a bit on both ends to get a flat and square surface. Unfortunately the interstage is not quite round. I’ll have to do more work here to get a more rounded part. The nosecone was not pointed enough for the version that was on SA-5. I started tapering it a bit more. I’m almost there. I’m not sure how much more I can sand it though. I keep hitting air bubbles that prevent a sharper point. I’ll continue to try and refine it.
Sorry for the out of focus on the interstage pic above.