Estes Skylab #001973, Build, Part 19, Almost Ready For White Paint

And now, back to our regularly scheduled program . . . 

Here's the seam side of the low wrap before the lower launch lug was glued on.

The wrap seam fill was medium CA glue.

Squeeze a drop of CA on scrap cardboard.

Dip a toothpick in the glue and drag the drop of glue down the joint seam.

Fold a piece of 400 grit (not a sharp crease) and sand the glue in the joint.

Run a dull knife blade over the filled seam - If you can still feel a seam gap, do another fill and sand pass.

 

On the details wrap, you can see the joint where the corrugation space is a little wider. 

The joint seam is filled, smooth and not that noticeable.

The upper wrap joint fill.

On this build I tried to fill the joints at the tunnel ends. 

I used the toothpick/dip CA glue transfer method but I found the dried CA hard to sand. I was concerned I might sanded through the thin plastic. Dried CA is much harder than the vacu-form wrap.

I didn't sand through it. Results were just OK, I wouldn't recommend filling the tunnel joints the way I did. Some of the White/black color separations fall right on the joints anyway.

Estes Skylab #001973, Build, Part 9, Adapter & Third Stage Wrap

Double check the Third Stage Wrap to be sure you know the top and bottom. I marked mine TOP on the inside wall in pencil.

Tape the wraps down before spraying and adhesive on the back.

Notice the wrap is a little taller than the top of the body tube.

The instructions show the Third Stage Wrap being glued  down before the Body Wrap (adapter) Reduction.

GOTCHA: I'd recommend sticking down the Reduction (adapter) wrap first, then apply the Third Stage Wrap.

I had what I thought was a near perfect fit of the Reduction (adapter) wrap by itself before the Third Stage Wrap was in place. 

I followed the instructions placing the Third Stage Wrap first. That spaced out the fit of the Reduction adapter fit making a gap at the butt joint.

I had to cut a small slice around the low end of the Third Stage Wrap as it was laying over the top edge of the cardstock shroud. This should allow the vacu-form reduction gap to close up a bit. 

This picture shows a dry fit. The gap is shown  before the thin slice was cut from the bottom of the third stage wrap. 

After removing a bit off the Third Stage Wrap, the gap is still there, but no where near as wide.

Estes Skylab #001973, Build, Part 6, The Vacu-Form Wraps

There are no shortcuts to fitting the wraps.

Wrap around the tube and mark the overlap. Trim a little oversize.

Then sand and check the fit. 

Repeat until both ends match up with (hopefully) an equal spacing between the ribs and very little seam to fill.

Notice on the right side - pencil marks to reference the 1/16" wide edge border cut.

Before spraying the backs with adhesive - 

Double check to be sure you are spraying the back side.

I use a small roll of tape to hold the wrap down on scrap cardboard for adhesive spraying.

Spray directly over the back, not from the sides. You want the adhesive just on the back. It would be difficult to remove adhesive from between the corrugation ribs.

I used the 3M Super #77 permanent spray.

You will be lining up the left edge of the wraps down the vertical pencil line.

GOTCHA: The Upper 2nd Stage Wrap end does not start on the pencil line!

Check the single conduit position on the Second Stage Wrap and line up the conduit top in the upper wrap to find the correct start position.

Be sure to double check the alignment of the conduits. Sight from the rear. 

If they are not in line, the conduits will end up looking crooked on the finished model.

A few points didn't want to stay down on the body tube.

Some CA glue was slipped in on a knife blade.

A smooth pointed dowel held down the raised areas as the glue set up.

Semroc Point, KV-58 Build, Part 6, NC Canopy Wrap

 

Here's the Cockpit canopy sticker supplied with the kit.

On my original Semroc Point build, the canopy didn't line up well.

Instead of laying down the side edge first -

Viewed from the rear, set the center line of the sticker down the length of the nose cone.

The sides of the sticker were then rolled over.

Notice how things lined up on the back.

It's not perfect, but better than my earlier build.

I did some light scraping of the black line to remove it.

With the line gone, the angle of the overlap isn't noticeable.

Estes Saturn 1B, #7251 Build, Part 12, Upper Wrap GOTCHA!

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 sit  perfectly vertical in the upper wrap recess. If the edge is started on the pencil line, the upper wrap tunnel recess ends up almost 1/16" to the left of the lower wrap. (See right inset picture)

Extend lines up from the lower wrap tunnel recess and adhere the upper wrap positioning over the new pencil lines.

My two kits were pre-production. This upper wrap alignment might be fixed when the kit is released. Double check before adhering the upper wrap.

Here you can see the butt joint of the wrap edges, where they end up a little to the right of the original pencil line. (Enlarge the picture)

After spraying with 3M 77 and rolling around the tube, tape down the ends securing the joint. 

As with most wraps, the ends can lift over time. 

A drop of medium CA was squeezed out onto scrap cardboard.

Did the tip of a toothpick in the glue and run it down the joint and hold closed until dry. Medium CA can help fill the crack at the ends. 

Pick up any excess CA glue with a Q-tip before it sets up.

You can fold a piece of 400 grit and sand down the corrugation recess seam. If needed, go back and do another pass of CA seam fill. The medium CA should sand easily - don't sand through the thin vacu-form wrap.

Build time:

Fit and Adhere Upper Wrap: 45 minutes

Total build time so far: 8 hours

Estes Saturn 1B, #7251 Build, Part 11, Fitting The Larger Middle Wrap

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 to cut all the way through. Score the line about halfway in then flex and crack the plastic down the cut line.

Like the lower wrap, the overlap should be cut wider than needed then trimmed and sanded little by little to fit.

Wrap and mark the overlap with pencil. Don't trim to the pencil line on the first cut, go little by little and do the fine fitting with a sanding block.

Here's a good fit, you can see the joint seam at the top.

Don't spray yet - see the next picture.

Check the edges all the way around and see if there is any plastic flashing folded over, left after sanding. This can be removed with some light passes of 400 grit.

Build time:

Fit Middle Wrap: 40 minutes

Total build time so far: 7 hours, 15 minutes

Estes Saturn 1B, #7251 Build, Part 8, Adhering Low Wrap

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, directed down the seam edge. 

Immediately (before the CA glue can set up) a burnisher was pressed down the seam to seat the edges.

The butt joint seam is sanded with 400 grit wrapped around a soft cotton Q-tip. This gives you cushioned sanding.

A fin will be glued over and cover most of the seam. Pay attention to the low end of the seam which you can see on the finished model.

With the wrap lined up with the top of the body tube, there might be a little overhand on the back.

This was trimmed off with a sharp knife, then sanded flush with a sanding block. 

Build time:

Adhere Low Wrap: 20 minutes

Total build time so far: 6 hours, 5 minutes

Estes Saturn 1B, #7251 Build, Part 7, Fitting Low Wrap

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 the cut. Use a straightedge and a new, sharp knife blade. 

The ends are trimmed to 3/16" from the start of the corrugations. I left mine long before marking the butt joint with pencil.

The first cuts are long, a slight overlap still exists. 

I'd rather sand the edges to size with a sanding block until the ends meet up.

The wrap is flipped over and taped down to a piece of scrap cardboard for a spray of "77" adhesive. In the picture, under the wrap - Roll tape into a small loop, sticky side out.

I prefer the 3M 77 spray. It allows for lifts and repositioning before a more permanent bond sets in. Chances are very good you will need to lift the wrap and try a second time to get it to match up at the joint ends.

EDIT: Before using any adhesive (Spray adhesive or Super Glues (CA glue) on a vacu-form wrap, check to be sure it is compatible. Save some of the border scraps and test first!  

Build time:

Fit Low Wrap: 20 minutes

Total build time so far: 5 hours, 45 minutes

Centuri Vector V #KB-2 Build, Part 8, Coolant Vane Base

In the original kit, Centuri had you cut the vane coolant pattern off the thin 20 lb. paper instruction sheet. I wanted a little more visual relief so it was redrawn to fit the BT-20 and printed on 110 lb. card stock.

I pre-curled the pattern. Even though it is flattened out for the adhesive spray, the pre-curl will help the fit of the wrap.



From the Centuri instructions:
This shows the possibilities with the four different root edge choices and different placements of the coolant vane pieces.

Plan ahead for your favorite look.

The vane pattern pieces were taped print side down on scrap cardboard.

You could use a thin coat of glue, but might end up with some wrinkling.
I used the Scotch Super 77, the same stuff used on the Saturn V vacu-form wraps. The back side was lightly sprayed.





I'm building two different Vector Vs, one with the coolant vane position at the top, the second almost at the bottom of the 6" BT-20 tube.






As usual with the Super 77 adhesive, the ends can lift.
A small bit of glue was sneaked in on a knife blade.
The ends are burnished down with the back end of a Sharpie barrel.

Quest Future Launch Vehicle #3013 Build, Part 5, Fin Skins

Here you can see the difference in the kit fin laminate on the left -
and my thicker fin laminate on the right.








For a leading edge that won't peel back, cut the top edge long, not down the gray print line. This top extension will roll over the leading edge for smoother coverage.

Here's how the laminate sits, glued on with a glue stick.

On the right is the top rolled over and onto the other side. The right side laminate print glues over this side.

All three fins -

I did mess up, nothing major. One fin should have a triangle on both sides, the second has circles and the third fin a square. I got them mixed up.
Look close, you can barely see the rolled over top edge under the skin.

Estes Saturn V #1969 Build, Part 13, Cutting Out The Vacu-Form Wraps

The vacu-form wraps are cut out with a 1/16" border. That border gives you a small flat edge surface for the spray glue adhesion.

I tend to cut the seam sides (right and left sides) wider than 1/16".
The wrap is rolled around the tube and the over lap marked with pencil.



The overlap is cut off, the same width on both sides.
TIP: Notice my ruler is turned over so the metal side is closer to the wrap. I don't want to take any chances raising the cutting guide, the blade angle could change.
TIP: Tape the wrap to your work area so it won't shift when cutting.

Wrap the wrap, trim a bit and check again until the butted up edges are close and have a very slight overlap.

When you get close to a near fit, sand the overlap to the perfect fit.




Here is some of the left-over trimmed edges.

Save these, you might need them to fill a gap if the ends were cut too short.

Each square wrap takes about 5 minutes to rough cut out, the inter stage wrap took twenty minutes.

Here's an example of the inter stage wrap to show the 1/16" glue border.

The Body Wrap Reduction and Third Stage Wrap will be covered later on.
Assembly time so far:
 5:35 minutes previous
 0:55 minutes this post
 6:30 total

Dr. Zooch Saturn V Build Step 7 Apollo Spacecraft Wraps

I've already primed, sanded and painted the LES dowel.
For no real reason, I decided to glue on the Boost Protective Cover wrap first.

Much like the adapter wrap in Step 4, the fit was a little off. The instructions tell you there will be a little sanding needed for the low end to match up.

While holding the wrap in place, a pencil line was drawn around the low end.
With 220 grit on a block, the balsa and some of the painted area was sanded down.

To square up the rough edge, I used the end of a motor mount tube.

The tube was slit for a tighter fit.
It was held tight around the body tube and the edge turned against the white paint lip.

This pressed back the balsa and paint giving a sharp straight edge for the wrap to butt up against.

Even with the extra prep, the wrap was still a little tall.
I may make a disk out of card stock so the service module has something to glue onto.

You could just trim and sand the wrap flat with the top, but I don't want it short or lose any of the wrap detail.

Dr. Zooch Saturn V Build Step 4 Adapter Wrap

The instructions have you form and glue the adapter together and glue S-IVB tube before test fitting the wrap.

The S-II / S-IVB adapter wrap was cut out and a test fit was done before gluing anything together.

The wide end of the wrap didn't meet up, the small end fit seemed to be fine.

A block with 220 grit was used to take the wide end down a bit.
You can see the balsa starting to show through the white paint on the wide end.

Earlier, the adapter didn't get the grain filled or hit with primer. But, the white paint may have swelled the balsa some.
Not a big deal, the block kept the side angle straight.

After gluing on the wrap, the fit is okay, still a hair wide at the bottom end.

Note the S-IVB tube isn't glued on yet. It was slid on to test the fit of the wrap.

And, the other side of the wrap.

The fit should be good, but any problem areas will be covered up by wraps D and E shown in step 5.
Earlier I masked off the tubes where all the remaining wraps would be glued on.
The masked areas are slightly narrower than the wraps. When the wraps are applied they'll cover up the open areas.