OTW 1/100 Vanguard build thread - a step by step pictorial

[novagator]

Yeah, what George said. http://www.subcommittee.com/forum/icon_biggrin.gif

Yeah, what George said.

[eckloss]

Sorry, I just realized you

Sorry, I just realized you asked for an update!

I spoke with David at the Regatta. Work on the Vanguard will continue again soon. Once it does, and I have more video and photos, I will be sure to post them.

Erich

[georget]

Well, I'll have pictures of

Well, I'll have pictures of my FINISHED Vanguard in a week or two! Keep you all posted.
George

[eckloss]

David is back to work

David is back to work on the Vanguard.

I'll be posting more photos and updates as work continues.

Below, a few pics of the pumpjet in progress.

e.

[eckloss]

...more work. Comments are from

...more work. Comments are from David.

Well, I'm finally back in the saddle on the turnkey VANGUARD project again. It was put off a few months prior to and after the SubRegatta. But, things are back on track now and I'm about ready to complete all the master work and cast up the new parts.

I want to make it clear that this kit from OTW is the exception to the line of excellent kits they put out; the VANGUARD masters became available from an outside source and did not fully capture the 'as built' configuration of the SSBN submarine now operated by the Royal Navy. In an attempt to make it a more faithful representation of the prototype I'm building new appendages -- the below discussion of work on the new pump-jet an example -- as well as working up the hull; all in support of producing for the client the best detailed and running r/c submarine of this subject out there today.

Hopefully, by the end of the week I will be done with the new rotor master, completing the masters (three parts) of the PJ. This will represent the most challenging and difficult aspect of the project.

Stay tuned, sports-fans.

David,



Here we're looking at the nearly filed out fillets between stator blades and stern-cone. The fixed stator blades translate linear water flow into a helical (radial) motion which intersects the rotor (screw type propulsor) in such a way as to reduce the incidence of flow to the blades of the screw while at the same time increasing the relative velocity of the flow to the rotor (as compared to the normal linear flow). I'm guessing here, but I think that the efficiency of the propulsor (the stator-shroud-rotor assembly) here, categorized as a 'pre-swirl' type, derives a performance benefit by preloading the incoming flow with a helical motion that is not entirely redirected by the rotor; the net thrusting flow of fluid (assuming perfect propulsor design) is linear -- little energy is lost to helical motion of the water mass.

The big deal to us is that the net torque of the PJ is at or near zero. The liability of these things are their huge silhouette i.e., they act to over stabilize the boat in pitch and yaw, making the submarine less sensitive to stern plane and rudder commands (the submarines center of pressure is farther aft when equipped with a PJ than if it were outfitted with a conventional enshrouded screw type propulsor -- the farther aft the c.p. from the c.g. the more stable and harder to turn).



After mounting the twelve stator blades onto the tail-cone (using a rotary table as part of an alignment/assembly jig) with CA adhesive I slathered on Evercoat Glazing Putty (a misnomer -- the stuff is actually a two-part polyester resin filler) with a stiff brush and then ground that down to achieve the tight radius' between blade and tail-cone. Here you see how I turned common round files into curved files. The curved files needed to negotiate the convex and concave faces of the blades were they intersected with the tail-cone. Each round file was brought to a red heat with the torch then bent with the round-jaw pliers to the desired radius. Nothing to it!



Most raw metal surfaces afford a very poor adhesive bond to primer and/or paint. In the case of white metal and other non-Ferris alloys it is best to achieve the rough surface by 'pickling'; the process of chemically attacking the metal with an acid or base liquid to oxidize or corrode the metal surface -- producing microscopic pits that give mechanical 'tooth' to the primer. This chemical texturing of the metals surface works to produce a tight bond between metal and primer. I use Ferric Chloride acid, the same stuff used for cutting electronic circuit boards. You did the work in the acid, brush the surface to insure complete, uniform attack of the metal, rinse in water, dry and you're ready to prime.



The unit was primed using Lucite brand (DuPont) 131S Automotive Acrylic Lacquer primer. Here applied with a Paache H Model spray-gun. The primer has a great deal of flexibility]http://www.minitek.com/vanguard/b-014.jpg[/img]

Test fitting the tail-cone to the shroud. Looking good. ####! ... I'm good! I'll cast these items individually, making life easy as I make tools and castings.

...more to come.... -Erich

[eckloss]

more work...comments are from David.

http://www.minitek.com/vanguard/b-020.jpg

Just

more work...comments are from David.



Just about done with the 1/100 VANGUARD rotor for the pump-jet propulsor. The below photos show the work.

Months ago I cast up the blades and set up the blade assembly jig. Today I finally got back to it and stuck all eighteen blades (holy ####!) to the hub. Now, a days worth of filling and fillet making to get the rotor ready for tool making.

And with the completion of the rotor I finish the three subassemblies of the propulsor. From there I make a new sail master (just can't face the rebuild I'm doing on the original kit part anymore - I've so thoroughly screwed that piece up!). Then masters for the masts and antennas. And then the making of the rubber tools needed to produce all the resin and metal parts needed to get the VANGUARD model completed.



A blade was taken, the hub cut to accept about 1/16" of the blade root (when CA'ed this gives a very strong union) and the blade tack glued and checked against this gauge to assure that it had the correct pitch and rake -- several times I had to remove the blade, reposition the hole in the hub and try again, till I got it right. In foreground you see the other blades, atop a graphic representation of the eventual propeller, this document prepared over two months ago. To the left sit the finished duct and stator-tail-cone subassemblies.



The hull with its attached 'setup' blade was mounted on the rotary-table and a Milliput (thanks, Dave!) 'crutch' formed that captured the exact geometry of the blades forward facing surface. This crutch, attached to a removable blade-assembly-jig, would later insure correct, exact placement of each blade about the hub, each a uniform twenty-degrees separated from its neighbors.

On the rotary-table I marked off each blade location onto the face of the hub. Removing the hub from the jig I used a high speed drill bit to route out the holes needed to accept the base of each blade. Not that the white metal blades were pre-primed before assembly, but their roots have been tapered to ease assembly onto the hub.

[eckloss]

More work... comments are from

More work... comments are from David.



Off-jig I ground out depressions within the hub to fit the root of each blade. Here, remounted onto the jigs four-jaw chuck, attached in turn to the rotary-table, is the hub which has received the first blade. The 'crutch' of the alignment arm holds the blade in position as I apply thin formula CA adhesive to set the blade in place on the hub. Typically I use Evercoat two-part filler to form the crutch, but this first-time use of Milliput in this application has convinced me of the materials superiority in this application.



The blades being added, the brown material is phenolic micro-balloons - I use them here as a grout, a pliable material to fill the gaps between hub openings and surfaces of the inserted blade. The high pH of the micro-balloons permits a quick set to the applied CA when the time comes to glue things in place. Note that I've ground down the sides of the crutch as to prevent its interference with adjacent blades.



The crutch piece has to be removed after a blade has been glued in place to permit rotation to the next position. The two machine screws that hold the alignment fixture to its table assure proper registration. You can see here clearly the brown grout used to fill the voids between hub hole and blade surfaces. See the triangular indexing mark on the hub -- that was the first blade to be permanently bonded in place -- point 'zero.'



I tilted the assembly jib to get gravity to work for me as I packed in the grout and later applied the runny thin formula CA adhesive.

[eckloss]

More work... comments are from

More work... comments are from David.

(The attention to detail on this project just blows me away!)



Once the rotor had been given two coats of filler, it all was worked down with a modified jeweler's rattail file and a modified Flexi-File sanding stick. The objective was to create a very slight fillet between rotor blades and the hub. This was the most time consuming and exacting step in the entire rotor master fabrication.



Close-up of the rattail file at work. As a point of scale here]http://www.minitek.com/vanguard/b-042.jpg[/img]

Back on the lathe, I cut off the dunce-cap portion of the hub. This was done so I could later cast the dunce-cap from resin and cast the rotor out of metal -- when metal casting the object is to minimize the amount of metal introduced into the cavity, done here by separating the dunce-cap. This was the scariest part of the rotor fabrication ... one wrong move of the tool-holder and those blades would be toast!



My primer gray pump-jet propulsor subassembly masters next to the kit provided cast aluminum pump-jet parts.



The assembled dunce-cap-rotor-tail-cone unit next to its shroud. Bite the relatively high-aspect ratio blades of the rotor - I worked very hard to design this rotor in such a way as to get the total developed blade area under seventy-five percent of the disc, less the hub.

[eckloss]

Comments from David...

http://www.minitek.com/vanguard/b-050.jpg

I spot glued

[color=#000000]Comments from David...



I spot glued the tail-cone/stator unit to the end of the hull with thick CA adhesive. Note that there is significant 'overhang' of the rudders trailing edges over the break between hull and tail-cone.



The rotor and dunce-cap plugged in ... starting to look like something. In the foreground are the masters for the horizontal stabilizer and stern plane -- man, is that thing big! Like some American SSBN's the full flying upper rudder sits atop a vertical stabilizer. The break between stabilizer and rudder is at the surfaced waterline. Any of you geniuses out there know why this is done?



With this shot you get some appreciation of all the fillet work the pump-jet stators and rotors demanded. My hands are still sore! Just a friction fit of the duct to the stators here. Good fit.



The assembled pump-jet propulsor. Word to line-handlers]

[sam reichart]

beautiful work David....just beautiful... thanks

beautiful work David....just beautiful... thanks for sharing some of the knowledge and technique..

Sam

[eckloss]

I tell you what...this started

I tell you what...this started as a request for some nice looking masts on the sail and has progressed to a full-blown turn-key. Thank God it did...even though David called Brit boats in general "ugly", to me this thing is a real beauty. I could never have done it justice, not like this. It's just amazing what he is doing.

I'll be posting the work on the new sail soon. I have a few pics lined up.

e.

[collins class]

That pumpjet work is awesome.

That pumpjet work is awesome. Did you run a static test of the unit to see how much water she pushes through? I would be interested to hear how it functions in reverse as well.

Dave Welch's custom blade unit for his Trumpeter conversion moves some serious water and with the smaller blades and the angled stators this thing should move out.

Great craftsmanship and patience. Thanks for sharing these techniques.

Byron

[eckloss]

...just a tease...more to come

...just a tease...more to come very soon....

e.

[eckloss]

http://www.minitek.com/vanguard/c-003.jpg

The sail master was made



The sail master was made from two blocks of forty-pound Renshape model making foam -- this stuff is so dense it will take primer without looking at all like foam; it has the density and cutability (is that a word?) of seasoned Basswood. The reason for the vertical laminate is twofold]http://www.minitek.com/vanguard/c-004.jpg[/img]


Just some of the documentation used to work out the shape of the sail master. The working drawing is right-center. The kit supplied sail, now that I've completed ruined it, is discarded, and seen to the left of the drawing. Sorry, Bob! I'll never do it again! ...



The hollow of the sail was done with the aid of a drill press and then round and oval files. First, with big bits I drilled holes, then connected them with the files. Note that on the piece I have indicated the position where tapped holes will be placed to secure the sail (pieces) onto the sail. Running machine screws up from under the deck and into these holes will hold the sail in place. I prefer my r/c submarine models equipped with as many removable parts as possible and the sail is no exception.



Before splitting the sail master (remember I only tack-glued the two halves together) I drilled two small holes through the trailing edge and two at the leading edge, where there was still plenty of 'meat' where the two halves meet. Later, into one half-sail would go pins that would be perfect fit into holes into the other half-sail -- assuring alignment and a good mechanical lock between halves when assembled, and easy disassembly for other operations.



The finished sides of the sail master, now ready for the top part which will have the cutouts for the many masts and scopes that adorn this r/c submarine model.

[eckloss]

Comments and photos by David

[color=#000000]Comments and photos by David Merriman...

Just about done with the Renshape top portion of the sail. I've opened up the many penetrations there for the various masts and watch-stander positions.

I've hollowed this piece out so that when you see an opening it will present and edge that is scalelike in thickness. I assume that the VANGUARD's metal in this area would be about 1/4" to 1/2" thick, so I ground the inside of the sail top piece to a nominal thickness of 1/32" -- still, at 1/100 that still is a very un-scale 3" or so, but still looks good at this small size. Any thinner and it would break in my meat-hook hands.

See what happens when a detail freak gets a turnkey job!!! ....It never ends!

Tonight I'll coat the inside and out of the piece with CA to harden it up a bit so I won't damage it through handling. Now I have to work out a foundation to hold the base of the scopes and masts -- that will be the structural element that takes the load as the masts are banged around by overhead traffic.

Next up]http://www.minitek.com/vanguard/c-010.jpg[/img]

After I cut the Renshape blank to plan I scribed the shape of the many penetrations that adorn the top of the sail -- these would guide me as I routed those holes out on the drill press. Note here that I've all but completed the scribing, but pencil marks remain at the locations for the snorkel induction and exhaust. I first mark down with pencil as a check, then, when happy with shape and location I then commit to an engraved line. No freehand work here, what I do is to scribe within the perimeter of pre-shaped stencils, some of which (both handmade and commercial) are seen above.



Using descending sizes of drill bits, I used them as router bits as I opened up the holes in the upper sail piece. Almost done with the port side of the sail top piece -- this work went with a surprising amount of precession]http://www.minitek.com/vanguard/c-012.jpg[/img]

After contouring the top of the upper sail piece with sanding drum and sanding block I started gouging out the interior to narrow the edge of the holes -- that has been done forward, note that the after holes still show the original thickness of the blank. Such work garners a good 'wow' reaction from the observer -- most people, when looking at a submarine model, look first at the sail and that's where the builder makes his first impression on his audience. Bad sail, bad impression; good sail, good impression. Very simple. Work harder on the models sail than any other component.



The initial grinding work to narrow the edges of the many holes. Drink only decafe when doing this type of work! Note the pencil lines bordering the bottom of the upper sail piece -- this defines were the unit mates with the sail proper.



The hollowed out sail piece ready for a coat of CA to strengthen this very thin (read]