1/144 Saturn I Block II SA-5 Build Update 7

It’s been a while, time for an update on the SA-5 build.

There are quite a few details that need to be added to the S-IV and interstage areas.  But before that I needed to add the payload section to the S-IV interstage.  There are a lot of details that go on the S-IV interstage and that would make it harder to get a relatively smooth transition from the S-IV interstage to the payload section (which includes the instrument unit).  I used CA to bond them and then started filling and sanding the areas to get a fairly smooth joint.

Payload section bonded to the S-IV interstage.

I then added the tunnel that runs down the side of the S-IV just to the left of Pos II.  This was made by laminating two strips of .010 x .100 strip stock.  I didn’t have any .020 x .100 stock so this worked out fine.  I also cut and shaped some .005 styrene sheet to make the antennas and an access hatch for the S-IV interstage.

Tunnel and antennas added.

I added two retrorocket fairings to the top of the S-IV interstage.  I thought about making some from styrene rod, but then it hit me to check my spare parts stash.  I had built a Saturn V last year from a mash up of the Monogram and Airfix kits, so I had a spare Airfix S-II.  It had retrorockets on the S-IVB aft interstage.  I pulled it out of the stash and checked it.  The angle was similar to the angle of the S-IV interstage and the size of the molded on retrorockets looked good.  I got my chisel blade out and shaved two of them off.  I then glued them to the S-IV interstage.

I then started adding details to the instrument unit at the base of the payload section.  It has several antennas, an access door, a rounded protrusion, and a panel that appears as though it may be somewhat thicker than an access door.  There are also a couple of antennas at the base of the payload section just above the instrument unit.  The documentation that I could find on the instrument unit is very sparse, but from photos and the few drawings I could find I think I have all the major details added.

I made the semi-spherical detail by sanding down a half pearl from a sheet I bought some time ago from Michaels.  I originally used them as rivets for a steam punk rocket I built a couple of years ago.  The thick panel was made from .010 sheet stock, the access door came from .005 sheet stock.  I made the large antennas at Pos II and Pos IIII with .020 x .040 strip. The medium sized antenna next to the semi-sphere was made from .020 x .030 strip.  The small antennas near a couple of the circular openings were made from .020 x .020 strip.  The last antennas added were the two tiny antennas at Pos I and Pos III on the payload section.  They were made from .015 x .020 strip.

Now it was time to add the fairings for the gaseous hydrogen vent pipes.  For this I started with the conical section of the LH2 fairings from the donor S-II.  I used white glue to temporarily attach them to a popsicle stick after cutting off the excess length.  I then used sanding sticks and a #11 blade to form them to the correct shape.  You can see them attached to the popsicle stick in one of the above pictures.  I used CA to attach them to the proper positions on the S-IV stage.  Then I cut some styrene tube (the same size I used on the S-I stage) to fit between the fairing and the base of the S-I interstage.  The base of the S-I interstage has an angle so I needed to try and match that angle on my tubes.  I then used Tenax to attach the front of the pipes to the fairings and CA to attach the base of the pipe to the S-I interstage.

Gaseous Hydrogen vent pipes added.

Next came adding a small umbilical panel to the left of Pos II at the base of the S-IV.  I used small sections of 3/64 rod to represent two of the pipes.  I then used a 1/64 drill bit to make the 10 small holes between the pipes.  I did not drill to the full diameter of the bit since the holes needed to be quite small.  I then used a 1/16 drill bit make the larger umbilical hole above the 10 small holes.  I again did not drill to the full diameter of the bit since the hole is smaller than 1/16 and also is not very deep.  Once that was done I added the four ullage motors.  I had to go the spare parts stash one more time to find a spare ullage motor since one of the ones that came with the conversion kit was not cast well enough to be used.  The other two came from the S-IB kit that is the base of this model.

Ullage motors and umbilical panel added to the S-IV.

Finally, I could put a coat of primer over the S-IV/payload part and see how it turned out.

The only detail left to add are the four S-I retrorockets.  They extend at an angle past the end of the S-IV section so I cannot add them until after I glue the S-I and S-IV sections together.  After that it will be time to start painting the white base coat.  I will not be using the conversion kit decals and instead will make some of my own.  It appears that the checkerboard pattern that goes around the S-I interstage has 10 squares from one Pos to the next.  The kit decals are off on that point.  There are also some other markings that are not on the decal sheets.  It is getting closer, but there is still quite a bit of work to do.

Thanks for looking.

 

1/144 Saturn I Block II SA-5 Build Update 5

A little more work on the S-I stage.  First I took out my Dremel and thinned the walls of the eight H-1 engines.  The kit engines have nozzle walls that are far too thick.  The picture doesn’t show it well but the walls are much thinner that before.

Engine on the left has been thinned, the right one is original.

Next I glued on the stub fins with CA.  When those were cured I added the large fins at Positions I, II, III and IV.  After those set I added the hydrogen vent extensions to three of the stub fins.

Finally, I glued on the inboard H-1 tubopump exhaust fairings.

Now the S-I stage is now complete and ready for it’s first coat of primer.  That will allow me to see where the final rough spots are and get them corrected before painting.

Here is a summary of what I added/deleted from the kit/upgrade parts.

  • All ribbing was removed from the base of the boat tail replaced with 14 ribs between each of the eight fin locations.
  • Access doors were added between each fin location and umbilical panels were added at two locations.
  • The engine fairings were removed from the base and glued back on after removing excess plastic.
  • Flame curtains were added for the four outboard H-1 engine locations.
  • H-1 nozzle walls were thinned.
  • About 1/8 inch of top of S-I was removed.
  • Kit fuel/LOX tank locators were trimmed before gluing the tanks in place.
  • Kit antennas were removed and antenna panels were added over kit locations and corrected antennas were replaced.
  • Electrical conduits were added to each of the four RP-1 tanks.
  • Gaseous hydrogen vent lines were added at three locations (replacing the update parts).
  • LOX and RP-1 fill and drain lines were added.
  • Vents were drilled at the top of three of the LOX tanks.
  • Vents were drilled at the top of two of the RP-1 tanks.
  • An umbilical door was added at the top of one of the LOX tanks.
  • Hydrogen vents were added to three of the stub fins.

Now it’s time to start on the interstage/S-IV stage.

Thanks for looking.

1/144 Saturn I Block II SA-5 Build Update 4

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.

Some of the details on the upper part of the first stage.

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.

Slit for stub fins added.

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.

Hydrogen vents for stub fins. Just a dry fit here.

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.

That is it for now.  Thanks for looking.

1/144 Saturn I Block II SA-5 Build Update 3

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.

Hydrogen vent pipes taped in place for a fit check.

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.

Antenna mounts and conduits added.

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.

Vent pipes removed from interstage.

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.

Fairings removed and heat shield moved to proper place.

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.

S-IV stacked on interstage.

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.

Fins trimmed to fit. Note the fairings that were cut off on the left.

That is it for now.  Thanks for looking.

1/144 Saturn I Block II SA-5 Build Update 2

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.

Thanks for looking.