Thursday, February 21, 2019

Mistake in Estes #1969 Saturn V Inter Stage Wrap? Part 1

On the NAR Facebook page, Jay M. Chladek may have found an error -
If the wraps are aligned (as molded) and shown in the instructions, the vertical half round wood tunnels may not line up between the Inter Tank and Inter Stage vacu-form wrap locations!

"ALERT: There is an error with the S-1C to S-II wrap as designed by Estes. The details on the S-1C part of the main wrap are clocked over by one position. The four sectors on the Saturn V are labeled Positions I, II III and IV. The S-II and Inter Stage part of the wrap from left to right starting at the seam are Positions II, III, IV and I. Unfortunately the details on the S-IC part of the wrap from left to right are Positions I, II, III, and IV. To fix that, I had to cut the S-II part of the wrap off the model after I had applied it! But I got it fixed and it didn't require much repair (thank goodness)."



"This is a scan from the instruction sheet showing the wrap as it appears in the kit. The problem isn't evident until you apply the wrap. If the modification is not made, it is amplified when the lower S-IC wraps are added as they help to align the two tunnel rails. If you don't reposition the wrap, you now have a tunnel rail going down the gantry swing arm side of the rocket and the umbilical port on the middle S-IC wrap is now sitting in a completely wrong sector."


"Here is the fix. It is easy to do, especially if you haven't glued the wrap on yet. Cut the wrap at the S-IC to Interstage seam, or at the seam below it (which I did to keep from damaging the ullage motor fairings). Then reposition the S-IC part of the wrap. If you do it right, the swing arm umbilical at the top of the S-1C should be perfectly centered directly under the access door on the interstage area. If done properly, everything below should align correctly on the shifted wrap seam while everything above should still align properly on the original wrap seam positions from the S-II on up (with the minor exception of the SII to S-IVB transition which should have the molded in access door also aligning with the swing arms/umbilical attachments as well). 

I contacted Estes about the problem and suggested they make an addendum to the instruction sheet. Whether they will or not remains to be seen. But the fix works and the rocket will be more accurate when done."

I haven't built the new #1969 Saturn V kit so I can't verify the alignment. It sounds like Mr. Chladek found the error and made the correction after noticing the tunnel pencil lines didn't line up! 



The #1969 Saturn V kit instructions are now posted on the Estes website: CLICK HERE
Go to pages 7 and 9 (right side of PDF) to see the tunnels and how they should vertically line up with the molded wrap tunnel locations.

On the left - It looks like they corrected the names on the scale kits page.

2 comments:

  1. Can you please expand on the sc-1 to sc-2 wrap error. I'm not familiar with sc-1 or sc-2 as well as the swing arm umbiblical, ullage motor fairings, SII to SIV transition. None of these terms are mentioned in the Estes instructions. I can see your change to the inter stage wrap but not sure I understand why except that is the way the Saturn V was actually assembled. Please expand jus try for detail construction purposes and much thanks for any details

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    Replies
    1. Hi Bryan,
      This applies if you are building the #1969 Saturn V kit.
      Please understand, I am not a "scale guy". Here's my best explanation.
      With the wrap (as supplied in the kit) glued down the pencil line on the body tube, the four ullage motors will be turned a little to the right.
      This puts the black vertical bands a little to the side of the four ullage motors. The edge of the vertical bands should be right against the side of the ullage motors.
      If you build it as shown in the instructions, most people wouldn't notice the difference. The black roll patterns are a little off.
      I don't know how they ended up this way. The next Saturn V kit (with Skylab section) will have the wrap corrections made.

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