Revisiting the Estes Maxi Brute V-2...

[James Duffy]

Time to turn our attention to the WAC sustainer at the pointy end of the rocket. Let's start by taking a look at the example built for the first Bumper WAC model documented at the start of this thread three years ago.

The WAC is a pretty simple prototype, and so was the model we built back then. The airframe tube is plain-old BT-20, and the nose cone was a plastic Estes cone sourced from a spare parts box (an Estes PNC-20A, perhaps?). The cone was lacking in a couple of ways. First, it was too short, and to mimic the scale cone length I extended the gray color onto to body tube below to fool the eye. Second, the ogive WAC cone used on both B-7 and B-8 terminated in a short point, not the blunt tip found on the Estes cone.

The spin motor was a particularly half-assed representation, spurred on by limited time and laziness. Rather that fashioning the complex tetrahedral shape of the prototype, I just cut out a diamond shape and stuck in in place. That won't do for the new model.

I reached out to my good friend Mike Nowak, who operates (along with his son Nick) a small firm called Galactic Manufacturing. Mike has developed some pretty extensive 3d modeling skills over the past few years for his magnificent Saturn V models, and Nick has become a virtuoso laser cutter artist. I whipped up a simple drawing of the parts needed, and sent that to Mike along with some photos of the WAC details. We went through a few virtual iterations of the parts until we had exactly the right vibe. Mike then printed the parts on his spiffy new printer, which uses some sort of unspeakable voodoo to produce parts without the nasty stratified lines that make so many printed parts unacceptable for scale models. Here are the results:

Finally, a hand-laid fiberglass airframe tube will be used instead of a paper tube. This was created early last year and is documented in post #143.



The fins on the original were lasercut from 1/16"-thick basswood and are attached to the airframe via TTW tabs which integrate with a 13mm motor mount. Unfortunately, the maker space where I had access to a laser cutter imploded in a nasty bankruptcy a couple of years ago. In a rare case of technological regression on this model, the new fins will be cut by hand, in the manner of a cave-dwelling savage.

More later,
James

 

[Leo]

"...., the new fins will be cut by hand, in the manner of a cave-dwelling savage. " which should be an absolute synch for you

 

[BEC]

Some cave dwelling savages are more savage than others?

 

[James Duffy]

Our next step in assembling the WAC sustainer is to sand the primer surface on the fiberglass tube, then respray the tube with Tamiya white primer. The irony of removing primer to add more primer is not lost on me.

Hacking the fins out of basswood with a rusty prison shiv #11 blade was the next task, after which the edges were stacked and sanded.


A 13mm motor mount was built, complete with kevlar shock cord, then mounted into the airframe tube.

An Estes tube marking guide was then used to mark the locations of the four fin locations. This is a simple little tool, but it has proven remarkably versatile over the years.

The slots for the TTW fin tabs were next cut into the airframe tube.

With the fin slots cut the fins are dry-fitted to check the slot widths.


More later,
James

 

[James Duffy]

Let's take a closer look tab a WAC being prepped in advance of the B-7 launch in July, 1950. In particular, note that the rocket is not a single, unbroken tube. Instead, it is a series of stacked tube segments with subtle seams between each portion.

Unfortunately, I've never found a decent reference showing the dimensions or number of of each of these segments. Marcin Bielicki, a Polish modeler friend, shared his workshop drawing of the Bumper with me recently, and that document allowed me to generate a pretty accurate guess.

Since the segment demarcations are so subtle, we're going to simulate them with pre-shading. Each location will be masked off, and medium grey paint will be airbrushed lightly along the tape at that location. Once we apply the final white color the grey lines will peek out from the lighter final color. (we hope, at least.)

Here's one of the segment locations masked off and painted...

...and here's how the airframe tube looks with all nine demarcations ghosted in place. Note that I've only masked one side of each line. The forward side of each line has a hard edge, while the trailing edge is fuzzy. The airbrush compressor pressure was set very low for this job, and the paint flow was set almost as light as it could be adjusted.

Note that we did this before attaching the fins, as the tube is easier to mask that way. While the tube paint cures we did a couple of cycles of diluted white Elmer's wood filler on the fins followed by sanding.

The fins were then attached one at a time with epoxy, using a simple laser cut fin alignment guide.


After the fins get a coat of Tamiya white primer we'll be ready to paint the WAC airframe.

More later,
James

 

[James Duffy]

Here's a quick photo-centric update. The dry transfers arrived yesterday, and were applied to the model today. Rather the recap the entire application process I will simply refer those interested to post #81 in this thread.

Here are the custom dry transfer sheets as they arrived from All-Out Graphics.

The transfers are applied, then the carrier sheet was carefully peeled away.

Here's what the aft section looks like with the transfers in place. This process is expensive, but the transfers are much better looking than cut vinyl or water slide decals, and are easy to apply. Additionally, the optical photographic process used for dry transfers is capable of producing much finer detail than any other marking method, although that fine detail was admittedly not needed for this project.

The additional B-7 transfers are for a future project. I also whipped up the trailing antennas using the process described way back in post #106, followed by an application of grain filler and a coat of primer. The antennas will be painted tomorrow, and I hope to get some more work done on the sustainer.

More later,
James

 

[James Duffy]

Work on the sustainer continued today, as the fuel line conduit and spin motors were primed and added to the model. The fuel line was attached using 3M #465 dual-sided tape, and the spin motors were mounted using small dots of epoxy.

With the fiddly bits in place the final color coat was airbrushed onto the sustainer with Tamiya X2 acrylic white. Thinned paint was used, and was built up in multiple thin layers until the point that the underlying gray was just barely visible. I'm really pleased with the results that this preshading process yielded, and the underlying lines really do look like subtle tank section demarcations.

There is a catch, though. The white on the sustainer contrasts pretty abruptly with the matt white lacquer on the V-2, especially in low light. In brighter conditions such as sunlight the contrast isn't nearly as noticeable.


Ultimately I may need to find some way to lighten the tone on the sustainer, but I'll defer any decision until the weathering is in place on the V-2.

More later,
James

EDIT: I should also mention that the nose cone was airbrushed with Tamiya XF-66 Light Grey acrylic, which isn't really light at all, and is more of a medium shade.

 

[James Duffy]

At this point we've effectively completed a clean, factory-fresh interpretation of a Bumper WAC. The problem with that is that there was never any such beast! The V-2 rockets that were flown in the US after WWII had all been produced deep underground, in a subterranean factory staffed with slave labor. At the close of hostilities the Nordhausen factory site was to be occupied by Soviet forces, so any available parts were franticly gathered by US and British troops in an effort to snag as much hardware before the site was turned over to their fellow ally. The V-2 parts were then loaded onto railcars, shipped to the port in Antwerp, and loaded onto ships for the long journey to the US, where they docked at New Orleans. From there the V-2s were again loaded onto trains for a journey across Texas to Fort Bliss. There, the components sat until they were needed for research flights, after which they would be assembled into completed rockets and flown in New Mexico. The B-8 and B-7 rounds added another cross-country journey from White Sands to Cape Canaveral before flying, at least five years after the production of their original parts. It is safe to say that the rockets had a few door dings and hangar rash before they took to the skies.

So, our next task is to take our clean model and add some grime. We'll be doing this in a variety of ways, starting with a dirty on wash on the joint connecting the fin section to the fuel tank section. Rather than document the process with photos, I'll just share this video of a dirty wash being applied to the midsection joint of a 1/24 scale V-2.


The wash is a simple mix of a tiny bit of black oil paint with a splash of Turpenoid thinner. The wash is applied with a fine brush, allowed to dry a bit, then most of the mix is removed with a Q-tip moistened with more thinner. Here's the result on our Bumper model.

We next move on to the nose cone of the V-2, where our goal is not only to add filth, but to accentuate all of the panel line detail we added a couple of months ago. The same process as above is used, except burnt umber oil paint is used in the wash. (The oil paint tube calls this color terre ombre brûlée, which I believe translates to "dirt man dessert," or something like that.)

The first step is very, very, important: you want to apply the wash to a smooth, glossy surface. This is so that the grime in the wash adheres to details as much as possible, and minimally to the smooth surfaces. Krylon 1305 UV-resistant acrylic gloss was used for this critical step. This is a specific Krylon product designed for fine art purposes, not hardware store-grade stuff, and can be found at Michael's and online. (Thanks to Jim Filler for suggesting this product years ago!)

After the gloss coat has been applied and allowed to cure for a few days, the wash is applied so that most of it wicks into the detail and crevices on the model. There is no need to be especially neat and fussy at this point, as most of the wash will eventually be removed. The priority at this point is to get the wash down into the rivets and panel lines.

Here's the wash after being applied to the rivet field below the antenna panel and access doors. While not shown in this picture, the rivet lines below were eventually slimed, as well.

Next, the majority of the wash is removed with Q-tips moistened with Turpenoid. I went through a bunch of Q-tips during this process (almost 50, perhaps?). After a Q-tip is loaded up with wash it should be discarded and the process continued with a new one.

Here's the final result of the weathering process on the nose cone. After the oil wash dries for a week or so, we'll spray this with a satin overcoat to knock down the shine. The process will continue down the airframe as soon as more gloss coat arrives.

In addition to the general grime being applied to the airframe, we are also doing some voodoo to the exhaust vanes we worked up earlier. Instead of a wash, we're going to use a process called drybrushing, where a tiny bit of contrasting paint is applied to a brush, then scrubbed onto a part in order to bring out detail. Here's a video quick tutorial of the technique being used on some of those tiny Warcraft miniatures:


On the exhaust vanes I started with some silver highlights, then knocked down the shine with some rusty brown.


More later,
James

 

[Mugs914]

Looking great James!

The weathering is one of my favorite parts of a build.

 

[James Duffy]

Additional Krylon gloss coat arrived a few days ago, and work started on weathering for the lower portion of the V-2 booster. Weather was great for this sort of thing, 70 degrees F with low humidity, so naturally everything went horribly wrong. As soon as I started spraying I knew something was up, as the Krylon 1305 gloss did *not* smell anything like the stuff I've used before. The gloss failed to, well, gloss, and worse than that it imparted a cloudy haze to the black areas on the fins. I suspect that the material has been reformulated since the last time i purchased some.

It isn't really apparent from this photo, but this fin looks terrible, with a fogged appearance.


So, I decided to repaint the black areas on the fins. Attempting to find a silver lining in this mess, we're going to try some preshading. After re-masking the first fin, fuzzy thin lines of Tamiya X-1 black acrylic were airbrushed onto the panel lines, then each panel was individually filled in with NATO black.

Yeah, we wrecked a bunch of dry transfers in this mess. I think that there are enough spares left to fix things, though.

The process was repeated on the two black sections on other fins. The preshading is clearly visible in these two photos, and you can see the black just barely peeking out from behind the lighter NATO black. I could not be more pleased with how this turned out, despite the unnecessary drama.


Morals of this story:
1) never trust a Krylon product, even if you have had good service from what appears to be the exact same product in the past.
2) always test a new can/bottle/whatever of any product on scrap material first.
3) Tamiya products have never failed me.

Next step will be to fix the simulated tape lines that have been obliterated during the repaint. After that, I'll let the fresh paint cure for a couple of days and then we'll get back to weathering. This project is finally in the home stretch.

More later,
James

 

[James Duffy]

A gloss coat has been reapplied to the lower airframe, successfully, using Tamiya TS-13 clear. After that cured for a couple of days the details were spoobed up with a burnt umber oil wash. As before, the majority of the oil wash was removed with Q-tips moistened with Turpenoid. As each Q-tip was darkened with the removed wash it was discarded. A rough estimate puts the Q-tip death toll at about 200.


Here's a interesting view of the contrast between the weathered fuel tank section next to the still-pristine tail cone and fins.

Here are a couple more views of weathered sections of the rocket. I'm especially pleased with how the weathering breaks up the monolithic tones of the smooth white fin surface.

With the weathering in place the exhaust vanes and trailing antennas are installed.


Our next tasks will be to paint and add the turbine exhaust and LOX vents, and add some detail to the pull-out port shrouds. After the oil weathering settles down for a few days we can spray the model with a matte finish.

More later,
James

 

[TangoJuliet]

Very cool! I'm still contemplating getting started on mine. I'm trying to finish up a couple smaller Estes kits first though.

 

[Mugs914]

TJ! Good to see you back around here!

 

[PXR5]

Lookin' good!
Thanks for posting your build

 

[James Duffy]

The finish line is in sight, and we simply need to add some little fiddly bits. Let's take a look at the pneumatic connectors at the tail end of the V-2. Here's one side, as seen on the horizontally displayed example at RAF Hendon and the vertical display at the Science Museum, London.

There are five connectors emerging from the bottom of the shroud protected by a plate on the RAF Hendon version. The Science Museum example lacks the plate, but we can see that the middle connector is longer than the others. We're going to exercise some artistic freedom here and model the pneumatic leads a bit longer than what we see here while combining features from each. Some scraps of angle styrene and rod stock are used for this step. The rods are mounted as overlong bits to aid in assembly and alignment, then cut down to size.

The opposite side of the rocket has a single larger pneumatic connector. This is modeled with a bit of styrene scrap. The turbine and LOX vents are modeled with 3/32" styrene tube.

After everything is sprayed with silver lacquer the detail bits are added to the model.

And with that assembly is complete! Our next task will be to spray the entire model with a matte finish, then get a few good beauty shots of the whole assembly.

More later,
James

 

[James Duffy]

I thought I was finished with the model, but once I had it out in the sunlight a pretty egregious flaw was uncovered. I invested a great deal of effort in the preshading on the WAC sustainer to simulate the circumferential tube section join lines, but once that element was out in the harsh light it was clear that it was simply too dark, and would require some lightening. A couple of light coats of Tamiya Matt White lacquer were sprayed on, taking care not to obliterate the preshading effect. The results came out nicely, so here are a couple of glamour photos of the completed Bumper WAC.

Now that the project is complete, I'm already thinking ahead to how I can improve the next one, which will probably be the B-7 round. In particular, I'd like to build the next version as a mid-separation model to avoid the nasty nose cone/airframe seam. This would require a significant reworking of the internal staging hoo-hah, but I've already worked out in my head how it might all work together. I've also learned a great deal about weathering on this project, and think I can make significant improvements on future projects.

No idea when (or even if) this will fly. I may try to find a home for it in a museum and fly the next one.

Thanks for reading,
James

 

[John Brohm]

It's a great result, James, and any museum would do well to have it.

 

[TangoJuliet]

As much as I'd love to see a video of it taking to the skies, I understand your concern. Maybe you can get one more photo though of you holding the model. Some modelers may not be familiar with this kit and it's size, or lack of size compared to many mid-power models, and a photo of you holding it would put it all in perspective.

 

[Leo]

This has got to be one of the best documented and build quality threads on the entire forum. Excellent work! I thoroughly enjoyed it!

In my opinion the only option for flying it is if you are going to enter this in a scale competition event, otherwise keep it as display to be proud of or donate to a dedicated museum (which I actually did with my Estes V2 Round #54 some time in the late 80's).

 

[James Duffy]

Well, the conundrum of what to do with the Bumper WAC model has been solved! It was packed up and shipped off to a museum earlier today. I won't say where, as it sounds like there is a gallery reconfiguration underway that may take a year or two.

An update will be posted when it goes on display.

Many thanks to all that have followed this thread over the past three-plus years!

James

 

[Doug Rocket]

James,
Wow, impressed. Attended the virtual NARCON and saw your MARS rover build as well. I just got a hold of an ESTES V-2 Maxi and would like any pointers you may have on building one with as much detail as possible. I am going to use your rivet/hatche templates and rivet techniques you discussed. This thread is mostly of your Bumper WAC but I assume most of the nocecone and sustainer details are the same for the V-2 build. I am in Huntsville AL so going out to the museums here to check out the static V-2 displays. Thanks.

 

[Blast it Tom!]

I am soooo jealous! James Duffy has done it again! I just found this thread after completing an Estes 1/25th (24mm) V2 for my brother in-law. I'd love to have built something like this as a V2! But yes, I'd like to see a bumper fly as well. Beautiful job!

 

[Doug Rocket]

James,
Any chance you could post some detail pictures of your other completed V-2's you have built to use as reference. thanks.

 

[James Duffy]

Following consultations with my rocket buddies at NARAM this past weekend, it was suggested that I knock out another Bumper WAC for the upcoming World Championships, to be held in Romania in early October. That puts me on the clock for a quick build. Fortunately, I have plenty of jigs, molds, dry transfers, and patterns on hand, and won't need to reinvent the wheel this time. I also have a nose cone with 2500+ rivets already marked and drilled.


Fins are also underway. Note to self: buy more clamps so I can glue all of the fins at once.

This particular model will be the B-7 round, which was the second Bumper to fly from Cape Canaveral. The dry transfers are already on hand, and it has a few more intriguing details than the B-8 round. Can I complete this in two months? Stay tuned...

James

 

[TheAviator]

James, James, he's the man! If he can't do it, no one can!

 

[James Duffy]

We're about to attach fins, which is a good time to highlight a change from the previous two versions of this model. The drilled rivet details have already been applied. Also, the hatch details have been made from painfully thin .005" styrene stock this time and attached prior to fin attachment. The thinking here is that doing this now will reduce the amount of handling after fin attachment, and ideally prevent any cracking of the delicate putty that will be applied to hide the fin/tailcone seam. The thinner stock for the hatches also looks a touch more scale-like.



This build is going very quickly, largely due to the fact that the jigs, templates, patterns, and such are readily at hand, and there really aren't any problems to be solved. Next step will be to lay up glass tubes for the engine mount and WAC airframe.

More later,
James

 

[NOLA_BAR]

Following consultations with my rocket buddies at NARAM this past weekend, it was suggested that I knock out another Bumper WAC for the upcoming World Championships, to be held in Romania in early October. That puts me on the clock for a quick build. Fortunately, I have plenty of jigs, molds, dry transfers, and patterns on hand, and won't need to reinvent the wheel this time. I also have a nose cone with 2500+ rivets already marked and drilled.
View attachment 475053
View attachment 475054
Fins are also underway. Note to self: buy more clamps so I can glue all of the fins at once.
View attachment 475055
This particular model will be the B-7 round, which was the second Bumper to fly from Cape Canaveral. The dry transfers are already on hand, and it has a few more intriguing details than the B-8 round. Can I complete this in two months? Stay tuned...

James

I need to get some clamps, what size/brand are those?

 

[James Duffy]

I need to get some clamps, what size/brand are those?

Just cheap little 1" spring clamps from Home Depot. They're great for gluing the linings into acoustic guitar bodies, too. You can also get them in bulk from Amazon.

https://www.amazon.com/Wideskall®-M...=1627950824&sprefix=1"+spring+,aps,199&sr=8-1
James

 

[Cape Byron]

Seriously, I learn more from @James Duffy 's videos than I never did at skool.

 

[Blast it Tom!]

ONe looks at what he does with the details on that tail section and despairs of ever doing anything that fine... My goodness!