Biohazard build thread

[neil_w]

I've been working on sanding off the primer, focusing on the lower body and middle fins so I can that piece of assembly done. I'm having second thoughts about having pre-installed the fins; sanding around them has been a pain. I think next time I'll revert back to my previous method of just priming all the pieces separately before assembly. Pre-assembling might work better on larger rockets where there's more room to work around the fins, but at this size I don't think it was a win.

Oh, and in my zeal to get it done quickly, I think I over-sanded the fins a bit, resulting in the paper getting slightly roughened. Who can guess what I'm going to do about it?

Memes are fun!

 

[KenECoyote]

:rofl:

 

[neil_w]

I went over the roughened areas with some 800 grit (usually stop at 400 with the primer). I think it helped! A little. Maybe?

Anyway, I mounted the first middle fin. Here it is, clamped into my jig:

And here it is, all finished:

Neato, starting to look like something.

I still need to sand the ring, the pods, and the whole top half of the rocket. I'll be doing the pods next, so I can paint the insides and the glue them on.

And maybe, just maybe, I'll remember to glue on the launch lugs.

 

[neil_w]

More progress:


Also, because I was curious, I sanded down the nose cone. Feels pretty good I think. If I do a careful job with the paint I think it'll be very good. I still don't think I've achieved perfect symmetrical smoothness though.

 

[Cabernut]

Turning out really well! I'm sure once painted it will be spectacular!

 

[neil_w]

Turning out really well! I'm sure once painted it will be spectacular!

Thanks. Now I got the easy parts done, gotta start on the ring and the pods. I really want to test-fit the ring into there, because seriously who knows how well it's gonna fit. Couldn't do it last night because the fins were still drying.

I find it interesting to try to assign an Estes-equivalent skill level to scratch builds. I think this one probably ranks a three, which seems to be where I'm most in my comfort zone. (I also think this one has the makings of a good kit, although that's a separate matter).

 

[Cabernut]

If it were an Estes kit, I would say level 3 as well. I wonder what hurdles need to be leaped in order to turn it into an actual kit and say, sell a few on Ebay or something. You never know.

 

[rocketaholic]

that is a very cool design

 

[neil_w]

If it were an Estes kit, I would say level 3 as well. I wonder what hurdles need to be leaped in order to turn it into an actual kit and say, sell a few on Ebay or something. You never know.

I don't know but I have concrete plans in place to not figure it out. I have a dream to one day foist one of my designs on a real kit manufacturer and let them do all the hard work productizing it (and then they can reap the tens of dollars in profit such an effort would bring in).

 

[neil_w]

Test-fitted the ring, and as hoped it was just a bit tight. So I gently sanded the undersides of the middle fins...

...until it fit right. (Actually I think I may sand it just a bit more later). It turns out it is *very* difficult to tell if the three fins are asymmetrical, and if so which one needs to be sanded more.

Here it is, friction fit (wont be glued in until painting is well under way):

Also I sanded the ring itself (inside and out), and chuckled at the incredible spiral seam on the interior, which I still won't touch because no one will ever see it.

I also figured this was a good time to do a dry fit of the whole rocket (minus the pods):

Looking good I think. Top half of the rocket still needs sanding of course.

 

[Cabernut]

Looking sharp!

 

[Gary Byrum]

I get the biggest kick out of turning one of my drawings into a 3D model. I'm sure we all get that feeling on scratch designs. It's also interesting how fugly a design gets right before the paint goes on. Reminds me of my Aunt Helen. She wore that green overnight facial mud/cream to bed and prolly had sliced pickles on her eyes. Looked like something out of a B grade horror flick, until that came off and the make up went on.

 

[neil_w]

I get the biggest kick out of turning one of my drawings into a 3D model. I'm sure we all get that feeling on scratch designs.

1000 times yes. I find it a bit weird though after having already stared at a nearly photorealistic OR rendering for a while. I guess it's not too much different than having a face card on a kit for reference, but there's still an extra kick on a scratch design, no doubt about it. And there's still nothing quite like having the actual thing sitting in front of you, at least until they come out with OR for Oculus Rift.

It's also interesting how fugly a design gets right before the paint goes on.

I have had this thought many times, particularly when I look at some of the HPR build threads. In LPR I think the filler/primer is the biggest culprit, but it serves as a nice incentive to finish the paint job. A completely bare (unprimed) LPR rocket actually looks OK by comparison, though I would not be inclined to leave any rocket that way, other than my minimally-painted Cyclone, or a boost glider or something like that.

 

[Gary Byrum]

A completely bare (unprimed) LPR rocket actually looks OK by comparison, though I would not be inclined to leave any rocket that way, other than my minimally-painted Cyclone, or a boost glider or something like that.

I built a Holverson boost glider from some plans I found on YORF, and one of the pics shows the whole thing nekkid. The other one is where I painted the boost section but for the glider, the idea was to add color without adding any significant weight, so I used a marker and colored it. It was like using food color or something on bare wood. It didn't look all that grand but it worked well enough, and gave it something besides nothing at all.

 

[neil_w]

I built a Holverson boost glider from some plans I found on YORF, and one of the pics shows the whole thing nekkid. The other one is where I painted the boost section but for the glider, the idea was to add color without adding any significant weight, so I used a marker and colored it. It was like using food color or something on bare wood. It didn't look all that grand but it worked well enough, and gave it something besides nothing at all.

I experimented a bit with Sharpie but eventually decided to use a bit of Testor's enamel, brushed right onto the bare whatever, for the Cyclone. Came out a bit more opaque and waterproof than the Sharpie. I was happy with the result: just enough decor so it doesn't look bare, but not enough to add any significant weight.


One little lesson I learned on this one: if you're gonna leave the rocket bare (wholly or partially), be careful about extraneous pencil marks during the build, particular ones that end up underneath clear glue.

I'll be even happier when I get a chance to fly the darned thing.

 

[Amsterdam]

One little lesson I learned on this one: if you're gonna leave the rocket bare (wholly or partially), be careful about extraneous pencil marks during the build, particular ones that end up underneath clear glue.

I'll be even happier when I get a chance to fly the darned thing.

that looks nice! I know what you mean haha if your gonna leave it unfinished you have to bear that in mind from the start

biohazard is turning out fantastic!

 

[neil_w]

I remembered you, ya little buggers! I didn't exactly put you in the exact location I originally intended, though...


The forward lug is located (accidentally) around the CG location *without* motor. Whoops. No biggie though, I don't think having it too far forward really matters.

 

[neil_w]

I hand-painted the insides of the pods with Testor's Gloss Red. Using a 1/4" brush, it was pretty quick work. I will likely do the interior of the ring using the same way, rather than trying to spray it. It doesn't matter if the color doesn't *exactly* match the red I'll be using on the outside.

For now I did two fairly quick and sloppy coats; at the very end I can touch it up one last time if desired. In the meantime, at my next opportunity, I can now glue the pods to the rocket. Here's one of them:


Although this was quite easy, if the pods were much longer it would have gotten very difficult to reach the middle. I'll keep that in mind in the future when design more tube-y rockets.

 

[neil_w]

I glued on two of the three pods. I think the angled cuts on the pods will work out fine:


The method of pre-gluing the very thin balsa strips to the pods proved to be a mixed bag. No matter how hard I tried, I couldn't get the two surfaces (end of fin, balsa strip) to be perfectly straight, and therefore the two pieces of wood did not make perfect contact all the way across. Hopefully the glue + fillets will still hold adequately. However, they did work pretty well to help me align and position the pods correctly; I think they're about as straight as they could reasonably be. (Note you can't see the imperfect joint in the pod at the bottom of the picture because the joint is covered by a fillet).

As an alternative, I thought about a fin jig-like thingie to hold the pod perpendicular to the fin (something cut out of cardstock or foamboard, or I could even 3D print). Maybe next time I'll try that.

Crazy as it is, once I get the third pod on I'm ready to paint, and then the waiting game begins (first waiting for opportunity to paint, and then for the paint to cure before next color). It's looking like I can actually get this done before the end of summer.

 

[KenECoyote]

Looks great to me!

Also reminds me somewhat of a Klingon weapon (maybe mixed with a space ship). :cyclops:

 

[dhbarr]

Bat'leth fins, filing that away for future use

 

[Cabernut]

That red... The pod looks like it already has a biohazardous blood sample!

 

[dixontj93060]

Well I hate repairs so don't know if I'd ever embark on a design like this... For sure I'd use a big chute and fly low.

 

[neil_w]

Also reminds me somewhat of a Klingon weapon (maybe mixed with a space ship). :cyclops:

It does, kinda. I think it'll lose most of that quality when it's painted, because the preponderance of white in the paint scheme is very un-Klingon.

That red... The pod looks like it already has a biohazardous blood sample!

Ha ha, I thought that too. That Testor's red is really bright; I think the Rusto Apple Red I'll be using on the outside is a bit darker.

Well I hate repairs so don't know if I'd ever embark on a design like this... For sure I'd use a big chute and fly low.

Geez Tim that would be no fun at all. The fins should be fine, but I am not so confident about the pods. I am pondering ways to strengthen them, if not right now than when it comes time for my first repair. 3D-printed reinforcements are jangling around in my head, but we'll see. In the meantime, nice fat fillets with Titebond NRND and cross my appendages.

At the very least, this rocket will look nice for one shining moment on the launch pad before its maiden.*

Oh hey, since the last pod is now on we can do some naughty pics of the complete rocket in its underwear (the ring is still dry-fit):



Me likey. I cut off the tab on the engine hook so now the rocket will stand up properly on the pods (my first rocket since BARing that can make such a claim) but the glue wasn't really all the way set yet so no pics of it standing up. I shall have to remember to sand off the edge of the hook, lest Biohazard take a *real* blood sample at some point.

A bit more filleting on the pods and then it's ready for pigment. I am incredibly pleased to have gotten this far before the end of June, just doing a little each night. This would not be a very long build if done "all at once", but for me this was quicker than expected.



*No, I would not be happy if grievous harm should come to it, despite my flippant commentary

 

[Gary Byrum]

Sho nuff iza a purdy deezine. Bout time ta dress dat bish up and make us drool.

 

[neil_w]

Neato:


That is all.

 

[neil_w]

What's more fun than masking, I ask you? Nothing! Or perhaps, everything!

Fortunately, this round is not so critical so it went quickly. Just needed to cover the ring/fin glue joints, and the painted insides of the pods (which, in retrospect, I probably could have done after assembly.) Dowels were stuck in the launch lugs, the engine hook was wrapped and she is ready for the white base coat. I hope to get that done this weekend, but no guarantees.


This would probably be a good time to get my order into Stickershock23...

 

[Gary Byrum]

What's more fun than masking, I ask you? Nothing! Or perhaps, everything!

Fortunately, this round is not so critical so it went quickly. Just needed to cover the ring/fin glue joints, and the painted insides of the pods (which, in retrospect, I probably could have done after assembly.) Dowels were stuck in the launch lugs, the engine hook was wrapped and she is ready for the white base coat. I hope to get that done this weekend, but no guarantees.
View attachment 295691

This would probably be a good time to get my order into Stickershock23...

Here's a tip if you ever mask tube innards again. Cut a piece of copy paper slightly longer than the tube to go around inside and overlap itself a little. Smack on 1 (one) piece of tape in the center of the overlap, and check for gaps. The tape doesn't even have to go end to end if you get a good snug fit.

 

[neil_w]

Here's a tip if you ever mask tube innards again. Cut a piece of copy paper slightly longer than the tube to go around inside and overlap itself a little. Smack on 1 (one) piece of tape in the center of the overlap, and check for gaps. The tape doesn't even have to go end to end if you get a good snug fit.

Good idea, I will give that a try if there is a next time. Thanks!

 

[neil_w]

Here's a tip if you ever mask tube innards again. Cut a piece of copy paper slightly longer than the tube to go around inside and overlap itself a little. Smack on 1 (one) piece of tape in the center of the overlap, and check for gaps. The tape doesn't even have to go end to end if you get a good snug fit.

Actually I should clarify exactly what I did there, because it is a result off having learned from past experience. I have found that trying to accurately fit a single piece of tape to the interior circumference of a tube is Very Difficult, becoming propertionally more difficult as the diameter of the tube gets smaller. After having suffered through this multiple times when masking the ends of body tubes, I finally learned my lesson and masked the pods here using many small pieces. Specifically, I did not use any piece that extended beyond approximately 180 degrees around the inside of the tube, usually a bit less. Pieces of this size were very easy to insert and press down, and it really didn't take long to get a good, solid, mask that completely covered the interior of the tubes.

If I understand your suggestion correctly, the friction fit of the paper inside the tube is serving the masking function. Would I presume that you at least apply tape at the ends of the tube, to create a good seal? That sounds like a good combination to me: use the rolled paper to fill most of the length of the tube, and then just use a thing strip of tape at the ends to seal it off.

One final note: I used plain old blue tape here because none of it was intended to create sharp mask lines. Later on I'll break out the Tamiya tape.