S200 ANGARA/SA-5 GAMMON Build, Finally!!!

I made one set of booster bands to see how long it will take per Booster. 4 minutes.

Just barely, before waking, I had a vision of me making the booster strut and exhaust nozzle cone assemblies for my SA-5 out of foam, using wooden templates and the hotwire cutting method, then glassing the foam.
I had to get up and get started immediately, because if it is as efficient and easy as it was in my vision, I can stop making these pain in the butt paper transitions and trying to get them all lined up perfectly!
I'll print the profiles on paper, glue the paper to some lite ply, cut each profile in duplicate, then assemble the templates as tracing stencils to guide the wire.
when the foam parts are cut out, I'll sand the sharp edges, then glass them. They can then be sanded to final specs checking with my caliper along the way.
The Rocket Gods have seen fit to shine their graces on me today by golly!!!

Just knocked one out using the quick and dirty hotwire foam cutter that I made the other day, by just holding the paper template on the foam by hand. It came out good enough to prove the concept, and they ought to look great when I do them proper with the guide jig made of wood. I have not even had my coffee yet, but if I had to, I could make this a usable part! It will even reinforce my quick connect piece nicely.:clap:

Don't you love it when "the lightbulb goes off"! Congrats on the breakthrough!

brilliant perFOAMance!

Wow, that came out great.

You should make a video of you fabricating one of those, it's hard for me to picture how you actually do it.

Come to think of it, I'd also like to see a little video demo of your tube cutting jig....

neil_w said:

Wow, that came out great.

You should make a video of you fabricating one of those, it's hard for me to picture how you actually do it.

Come to think of it, I'd also like to see a little video demo of your tube cutting jig....

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I'll do that when I get around to it, but I have a bunch of real life inhibiting my progress for the next couple of days.

The tube cutter is an absolute joy to use! I even found the pieces to make it at the hardware store after I made it from stuff I found in one of my Mom's tool boxes.

I"m going to have to study your pictures. I can get nice, square edges but I ususlly have to do more sanding to get there than I like.

Screaminhelo said:

I"m going to have to study your pictures. I can get nice, square edges but I ususlly have to do more sanding to get there than I like.

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You mean on the foam part? I hit it gently with 120 grit right after cutting it out, as there were wispy/stringy things hanging off it. Shapewise the square edges are the result of using the paper template as a guide.
I used my crappy improvised hotwire, which is handheld, so when I get the proper one fully assembled, the edges should be perfect.

Quick and dirty hotwire:



Proper Hotwire I'm making:

Sorry, I was referring to the tube cutting jig. Maybe I mis-read what the previous post was about.

Screaminhelo said:

Sorry, I was referring to the tube cutting jig. Maybe I mis-read what the previous post was about.

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Sharp razor? How many passes are you using?

cavecentral said:

Sharp razor? How many passes are you using?

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I stick the #11 X-acto in the clamp, set to the right spot to make firm contact with the tube, then simply roll the tube against it while applying slight pressure.
I suppose it requires about three turns to cut fully. On small stuff it is easy to go around a couple of times til' it is cut most of the way around most of the circumference, then remove the tube from the jig and hit the sticky spots by hand, it already being perfectly straight anyhow, so you simply cut through the already scored parts that don't want to give as easily as the rest of the tube.
When I get around to making a video, I'll cut a couple different lengths of tube to show.

Don't worry, I did not stop building it, I just realized how light I could make it with some newly found methods.
The boosters can be made out of glass and foam in a mold, and and structural components that need to be mounted internally can be part of the process.
I will make a Master in positive, then press it into a molding compound, and make a negative.
I've been watching people fabricate all sorts of things by molding composites around foam, and I like what I see!
Now they all really will be identical, but I'll still weigh them and make certain.

Parts like the struts will get molded too, and it is almost a shame now that I have developed ways to fit carbon fiber to any shape.
They will require cutting with a jig, but the whole object will be one piece when it cures.
I will use the lightest weights of glass cloth, but there may be a carbon fiber spar or rib here and there.

Even the fin on the booster will be part of the mold, as it makes the ideal alignment point for the rear view template.

Top, I had to laugh the other day when the Denovians got me with an SA-5