Correcting the Lunar Models 41" Excelsior

[Vidar 710]

As I get closer to start the build, I've finally began looking deeper into the vacuum forming process. In doing so, I discovered that it's highly likely that the heat from the hot styrene will most likely damage if not destroy my masters due to the materials they are made of. I just ordered a large amount of molding and casting material to copy my masters. The molding material can take up to 450deg F. Plastics require up to 375deg F to successfully soften the plastic to form properly. I'll have the option to pull the plastic down into a mold or cast copies of the masters and use them as bucks.

Before all that, I have to start the corrections to the nacelle struts. This will be the last of the corrections, but there is a list of smaller scratch-builds to accomplish. In addition, Bob Morgan is in the works on the 3D print for the main cargo bay details.

Tracy

 

[Inquisitor Peregrinus]

Have you considered negative vac-forming -- plastic sucked down into a concave buck rather than over a convex? Good way to capture sharp surface detailing and not have to calculate for material thickness.

 

[srspicer]

Have you considered negative vac-forming -- plastic sucked down into a concave buck rather than over a convex? Good way to capture sharp surface detailing and not have to calculate for material thickness.

This is a good idea, that way you are only casting a hard copy over you master and then flipping the casting over to create your vac-form mold. Less expensive than rubber and less steps.

 

[Inquisitor Peregrinus]

Enhh... I'd go with UltraCal or similar -- something with little to no volume loss in casting -- and make an interpositive. Take care with the master, mould it in silicone and fiberglass. Make a copy, and then cast a negative buck off that.

Or, if you have access to a machine shop and 3D pantograph, mill the bucks out of aluminum by tracing the topography of the master with a stylus. With the adjustment settings, you could also scale up or down if you felt like it.

 

[ProfKSergeev]

Alternatively, you could make fiberglass castings. There would be zero loss of detail and sharpness and the castings would still be hollow. It is a bit messier than vac-forming, however.

 

[Starbase101]

A concern I'd have with vac-forming a part as large as the LM saucer is the size chamber you'd need and the amount of suction power to pull such a large part. Vac-forming also yields "soft" details - no way of getting crisp lines due to how it inherently works. In my opinion, casting would be more practical and give better results.

 

[Vidar 710]

The only parts I'm wanting to vacuum form are the saucer (top and bottom), the primary hull super structure, the secondary hull, the main body of the nacelles and their forward and aft upper hoods. None of these parts have any skin detail to pull, so I'm not concerned about that. Look back at what I've done to these main parts to simplify them for this purpose. I actually pointed up the edges in anticipation to vacuum forming them.

My options will be to pull down into the molds or make durable castings and use them as bucks. We are talking about very basic shapes here. The skin details will be scribed in or raised plate details will be added during the build.

I have a very large vacuum forming table that will be able to pull half the parts in one sheet.

Tracy

 

[Vidar 710]

Digging around, I found the Collective's vacuum formed Planetary Sensor Dome part at the bottom of my scraps pile. Here it is compared to my completely scratch built version. My master will be molded and cast in resin. However, the dome itself will be cast in clear due to two of the radii's radiate light.

 

[Iskelderon]

Digging around, I found the Collective's vacuum formed Planetary Sensor Dome part at the bottom of my scraps pile. Here it is compared to my completely scratch built version. My master will be molded and cast in resin. However, the dome itself will be cast in clear due to two of the radii's radiate light.

View attachment 1582900

Demonstrates the difference between "good enough for most people" and "full potential".

 

[Vidar 710]

Just a quick update on progress. Pics to come for the 3D modeling of the main cargo bay for the secondary hull.

Tracy

 

[Vidar 710]

With the computer skills of Bob Morgan, the Main Cargo Bay details are well under way.

The forward bulkhead, ceiling, and inner walls of the secondary hull within the Cargo Bay seem to be covered by several patterns of designer screen mesh material. My plan is to pick out the best-looking matches and mount them to a flat surface so I can mold them to cast copies. Thinly cast resin will be much easier to manipulate with heat to get the castings to conform the inner hull walls. The ceiling and forward bullhead are flat and should not cause any fit issues.

Tracy

 

[t2sides]

Wow Tracy!! That’s gonna look amazing!!!!
He’s doing amazing on the 3D parts!
I didn’t realize the Excelsior used those Leopold and Flak parts, that’s really cool!

Can’t wait to see how it all integrates into the model!!!

Keep the updates coming!

 

[publiusr]

I have often thought about a curved drop-ship that would fill the fantail cut-out from that connection all the way to the aft tip of the secondary hull…

 

[Vidar 710]

The main cargo bay greeble is done. I'm still searching for mesh material to re-create the inner walls and ceiling textures of the cargo bay. Additions to the Warp Nacelle greebles featured from the old MPC Darth Vader Tie Fighter kit's hatch are in the works. Further tweaking to the aft torp launchers are also underway.

One more flaw found on the LM's superstructure shape. Even AMT/ERTL got this wrong! The outboard walls abeam the Impulse Crystal and engine exhaust ports were mastered in the pure vertical. The superstructure on the studio model actually gets wider at its base.
As seen here:

The plan is to laminate a 1/8" x 1/8" strip of styrene at the base, then sculpt and plane in Smooth-On Apoxie Dough to create the vertical taper.

Scenes n film at eleven!

Tracy

 

[Vidar 710]

The above-mentioned Warp Nacelle details are finishing up and will be ready to print soon. See Darth's TIE Fighter hatch in this detail?
This assembly tucks in under the forward nacelle cowling.

A shot from the NX studio model

New update from something old...
Turns out the aft torp launcher 3D modeling needed a complete overhaul. Pics of that progress are coming too!

Tracy

 

[Vidar 710]

This should be the very last correction to the primary hull superstructure. The top taper is already fixed. The inboard and outboard tapers won't be a big issue. The plan is to laminate a stripe of styrene at the base of the chines, then trawl in Apoxie Sculpt to create the new tapers on the inboard and outboard surfaces. I'll share pics of the work.

 

[edge10]

This should be the very last correction to the primary hull superstructure. The top taper is already fixed. The inboard and outboard tapers won't be a big issue. The plan is to laminate a stripe of styrene at the base of the chines, then trawl in Apoxie Sculpt to create the new tapers on the inboard and outboard surfaces. I'll share pics of the work.
View attachment 1623993

Were these lines drawn by ancient astronauts?

 

[Vidar 710]

Here's a couple of shots of the new modeling of the aft torp launcher assembly, along with the addition of torp tube inserts for the forward launchers that are just below the dorsal neck.

I recently purchased a Elegoo Saturn 2 8K printer. I was spending a small fortune on Shapeways, so...

Tracy

 

[srspicer]

Would like to get your feed back on the printer, ease of set up, loading files, etc. please. You could message me so as not to de-rail the thread.

 

[Starbase101]

With all the amazing work you're putting into this model and now the CAD models too, is there any chance you might be offering copies of the upgrade parts for other people having this kit?