Protovamp - A Galaxy Class Predator

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Gary Byrum

Overstable By Design
Of course, the parts aren't going to pour out of the bag, and like with most scratch built rockets, the progress unfolds before you. I do have a gray-scale 2D drawing though. Protovamp has a BT 60 airframe, a BT 80 fin can and 3 BT 70 tube fins. The tube fin in the center is cut the same on both ends. We'll call this one 'the rudder' and the other 2 are quite a different approach to cut tube fins. I call em scoops/wings, even though all 3 tubes are 120* apart. Above the fin can area I have 6 (hard to see them all....use your "magination") Photon Flux Cannons. These are BT 20's with bamboo spires. I knew them skewers would come in handy.

Motor mount is 24mm and sports 3 pair of BT 5 thrusters. The nose will be hand turned similar to the one Carl made for the Tau Zero and this bird will stand at 3' 3". There sho nuff gonna be a lot of tube cuts on this rascal. I figured it was about time I built a tube finned rocket anyway. It's been since.....since...since..uh..er, since I was a kid I suppose.

Where's my "like" button?

qquake2k

Captain Low-N-Slow
That is going to be awesome!

Gary Byrum

Overstable By Design
That is going to be awesome!
Ought to be fun to build. I'll start with the cannons so I can install them like units. I'll have the usual photos of course.

Gary Byrum

Overstable By Design
I sorta got started yesterday with the cannons. 6 &#8211; BT 20&#8217;s cut 4&#8221; in length with curves cut and 6 spires. The spires are mounted on standoffs which have been heavily saturated in thin CA and will mount just inside the tubes. I suppose it might be wise to paint the insides before I mount the cannons. Basic black should suffice for any and all of the cut tubes.

The block for the nose was cut and laminated with ½&#8221; planks to dry overnight. Any time I make a nose cone for BT 70, I save wood and time on the lathe by laminating 2 x 2&#8217;s. I hate wasting balsa. Unfortunately, I won&#8217;t be using this particular block in this build because my dumb @ needs to turn one for a BT 60. Since I can do that with just a 2 x 2, I&#8217;ll save this nice lam job for another project. Already getting off to a rough start, eh?

qquake2k

Captain Low-N-Slow
Plasma or laser cannons?

Gary Byrum

Overstable By Design
Plasma or laser cannons?
I may have to change the name of these cannons. I did give thought about how they work. Basically, the cannons fire what appears to be a plasma looking oval shaped ball that can penetrate shields and the outer hull plating of a starship. Once inside, the "bubble" emits it's energy and starts demolecularizing the the internal structure. Then a tremendous spike in internal pressure begins to break the ship apart thus killing the crew and totaling the space craft, leaving the high tech equipment unscathed and other useful tech behind to be scavenged. This is not an explosion or else the technical goodies would be toast.

BABAR

Builds Rockets for NASA
TRF Supporter
I may have to change the name of these cannons. I did give thought about how they work. Basically, the cannons fire what appears to be a plasma looking oval shaped ball that can penetrate shields and the outer hull plating of a starship. Once inside, the "bubble" emits it's energy and starts demolecularizing the the internal structure. Then a tremendous spike in internal pressure begins to break the ship apart thus killing the crew and totaling the space craft, leaving the high tech equipment unscathed and other useful tech behind to be scavenged. This is not an explosion or else the technical goodies would be toast.
Plasers?

qquake2k

Captain Low-N-Slow
Sounds like new technology from the Pentaurus Cluster. Should give the Alliance the edge over the Dusahn.

TRF Supporter

neil_w

Marginally Stable
TRF Supporter
Woohoo, a good new scratch build to follow! Looks cool.

op:

Gary Byrum

Overstable By Design
Woohoo, a good new scratch build to follow! Looks cool.

op:
Now I have 3 unfinished projects. I did get my mojo back though. Just gotta drag that lander down and get jiggy wid it. I don't know why I'm putting it off. It's just a little paint, a little vinyl and a whole bunch of MASKING!

Gary Byrum

Overstable By Design
I realized my first idea was a bit overkill and would be a PIA. At first, I didn't think a single standoff would be sufficient, but when I considered the CA bath along with solid fillets, I made an executive decision. So I didn't really disagree. I just had a different idea. So....thank you again. Mr. Chi Man!

Gary Byrum

Overstable By Design
I thought about setting those cannon spires this evening but blew it off since I wasn&#8217;t in the mood to get all glued up. So I went at some tube cuts. I especially wanted to get the harder ones done first so &#8220;Off With Their Ends&#8221;. As you see only 2 templates, one is for the rudder. The wing template has double duty. I just flip it over and use the other side to mark the 2nd tube.

BAM! Look how fast that went! The rudder (in back) has the uniform look, while the wings look warped. The custom cuts did that. Hard to see in the pic, but both are identical and mirrored.

Here&#8217;s another shot showing a little better what they look like. After the last pic, I CA&#8217;d the edges so I could come downstairs. Tomorrow I&#8217;ll CA the rest of the interiors and all will get a nice smooth sanding.
Oh&#8230;.I cut the new block for the nose cone and the cardboard end caps are drying overnight.

BuiltFromTrash

Well-Known Member
Really cool! How did you attain the template shape?

Gary Byrum

Overstable By Design
Really cool! How did you attain the template shape?
Way back when, Apogee posted this cool tool method to make those. I incorporated it in Autocad and it works very well there. Usual template cuts are not so hard to do, but the custom cut on the wings was a B&^\$%! I toyed with it for hours before I finally got a handle on it. I don't remember where that posting is, but I did save the PDF file they posted.

View attachment Angle Tube Cuts.pdf

neil_w

Marginally Stable
TRF Supporter
It seems like the three tube cuts are extremely similar although obviously not quite the same. I'll be interested to see how the asymmetry of the wings looks on the actual model; it's hard to tell from the 2D render.

Gary Byrum

Overstable By Design
It seems like the three tube cuts are extremely similar although obviously not quite the same. I'll be interested to see how the asymmetry of the wings looks on the actual model; it's hard to tell from the 2D render.
Will the 2D drawing I first posted not help with that?

neil_w

Marginally Stable
TRF Supporter
Will the 2D drawing I first posted not help with that?
No, but that's OK, I'll get it when it starts coming together.

Gary Byrum

Overstable By Design
No, but that's OK, I'll get it when it starts coming together.
Dood! I know you have an imagination. I've seen your rockets!!!! Look at the 1st pic and imagine the fins pushed back to the 120* point and put a slight angle to them. It IS what you might imagine it to look like. Why don't you take that little 3D spoiler proggy you have....uh....er...Open Rocket? And do a rendering. Maybe that'll help.

neil_w

Marginally Stable
TRF Supporter
Dood! I know you have an imagination. I've seen your rockets!!!! Look at the 1st pic and imagine the fins pushed back to the 120* point and put a slight angle to them. It IS what you might imagine it to look like. Why don't you take that little 3D spoiler proggy you have....uh....er...Open Rocket? And do a rendering. Maybe that'll help.
Ha, if OR could do BT cuts like that...

Anyway, I see what it looks like, just don't get the feel of the differently cut tubes yet. All in good time.

Gary Byrum

Overstable By Design
Ha, if OR could do BT cuts like that...

Anyway, I see what it looks like, just don't get the feel of the differently cut tubes yet. All in good time.
Chalk up another win win for old school!!!
The only thing that has me slightly bothered, is hoping I made deep enough cuts on those wings. I want a dramatic appearance and I'll be a little disappointed if it isn't enough. Sure, me and Mr Dremel could modify if necessary, but I hope I don't have to do that.

Gary Byrum

Overstable By Design
Since I was going to install a baffle, I broke out the OLFA and my measuring card. I made this just for cutting baffles and CR&#8217;s when needed. Used a 1/16&#8221; hard poster board and poked holes with my cheesy hole punch.

I decided to finish cutting all of the remaining tubes this evening and treated the edges with CA. Earlier today, I mopped the inside of the tube fins with CA and let dry for several hours. These things are always a really tough job getting them smooth, but now the deed is done. Slicker than a baby&#8217;s butt.

Last thing to get done this evening was to install the spires inside the cannons. It could have been a real trick until I searched for some scrap balsa to use as a prop to hold them in place while the glue dries. That&#8217;s what&#8217;s left of said prop material behind the cannons. That worked like a champ. Periodically, I&#8217;d check the spires to make sure they weren&#8217;t tilted or leaning so, those were looking fine. Had to shut down early because that friggin chair was killing my back.

Gary Byrum

Overstable By Design
Thursday night, all I did was some busy work. Nothing picture worthy. I need 3 internal ribs to support the BT 80 on the BT 60 so I laminated some balsa with a thin piece of basswood to dry overnight. I assembled the motor mount, put fillets on the spire anchors and glued the baffle to the coupler. Everything was left to dry.

Today, I glued the motor mount flush to the end of the 6&#8221; BT 60 and mounted the coupler & baffle in the other tube. It seems almost pointless to have a baffle that far down the tube, but I really didn&#8217;t want to cut the 18&#8221; tube in the center. I guess it&#8217;s better to have a baffle than not.

I proceeded to cut the ribs from my homemade piece of balsa plywood making each one ½&#8221; wide. Usually, these kinds of installments are a little larger than they&#8217;re supposed to be because I draw with a zero line in Autocad which causes them to be oversized. I don&#8217;t allow for tube thickness and it&#8217;s a safety measure that keeps me from cutting them too small. I can sand them to fit which works well for me.
The BT 60 was marked in 3 places at 120* and I cut the glassine away from where my glue joints will be. Applied glue and set to dry. The same was done for the BT 80 where the tube fins will go. I tapered the ends of the ribs, installed them and set aside to dry.

Gary Byrum

Overstable By Design
Tonight, I got a late start and installed the motor mount assembly inside the BT 80. When I realized I hadn&#8217;t put fillets on the ribs, I made an effort to apply them while it was in there. WRONG! That&#8217;s 12 fillets I&#8217;m trying to knock out in a tiny area. Made a flipping mess. THEN&#8230;.I accidentally knocked over my water bottle. The lid came off and it ran all over the place. I was fortunate enough to get my parts and pieces out of the way with very minimal wetness, but I had a river to clean up. It took most of my available time, but now it&#8217;s cleaner than it was. I yanked the motor assembly out of the BT 80 and started a major scrap & clean. That part will survive. The BT 80 on the other hand&#8230;&#8230;So I prepped another one with like I did the first one and closed up shop. PHOOIE!

Gary Byrum

Overstable By Design
SO&#8230;..The clean up on the motor mount went well and I got those fillets on. Now that I&#8217;m pretty much done with multi tasking, the build will be one stage at a time. While the MM dries, I wrapped the tube fins with copy paper and stuffed the BT 80 with enough Christmas tissue and toilet paper to inhibit any black paint from going in too far. Rusto 2X works well without primer on tube interiors and over CA treatment. I did this on my Gyro Dragon and it still unchipped or falling off. All four tubes got the black paint treatment.

These are still pretty tacky, but I wanted to get the paper off before it stuck to the tubes. I knew there would be some wicking and a little paint bleed to the surface, but that worries me not. I got some real special plans for the tube exteriors.

neil_w

Marginally Stable
TRF Supporter
Looking nice... is that flat or gloss?

Gary Byrum

Overstable By Design
Gloss. I only use flat when I'm doing a white base coat.

Gary Byrum

Overstable By Design
I knew there would have to be a few things that got painted before assembly and some were tube interiors. Here&#8217;s a of pic of the cannons and thrusters that got their black pre-paint. I also opted to get a little black on the motor mount before I installed it that might be visible. Personally, I don&#8217;t see finishing the interiors with as much attention as I would exterior pieces as they will likely get less attention and not matter as much. If I were building a museum caliber model, that would be different. But it&#8217;s for flying and I can get away with it on that level. The tube fins on the other hand got the CA treatment and the black pops out like a fine finish. This is hard to see with the new LED bulbs I installed in the shop. None of my pics look the same anymore.
The nose cone got a good sanding and another coat of filler. I wasn&#8217;t as good with this one as some of my previous turnings. The shoulder is a little loose and will require some paper layering. I&#8217;m going to cover the glue joints in the BT 80 with Tamiya tape before I paint it. And since I&#8217;ll be papering the tube fins & cannons with prints, I&#8217;ll prep those glue joints after the fact. Can&#8217;t say I&#8217;ve ever done so much pre-painting on a rocket before.