Diamond Cutter build thread

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That is a nice fin jig! If you want to make a set of bigger ones for 1/4" 3/8" and 1/2" I'm in to purchase all five!

(Actually I'd probably an 1/8" and 3/16" also).
 
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That is a nice fin jig! If you want to make a set of bigger ones for 1/4" 3/8" and 1/2" I'm in to purchase all five!

(Actually I'd probably an 1/8" and 3/16" also).

Additional design work would be needed to go up to those larger sizes (1/2", yikes; I assume those would go with correspondingly gigantic airframes), and I'm not equipped to do it. Also, the 3D prints would start getting expensive up in those larger sizes.

So I'd say the current design could work reasonably well up to 1/8" (and even then changes would be needed to accommodate larger airframes), but above that it's dicey.

I'm happy to provide the CAD file if you want to play with it. :)
 
Additional design work would be needed to go up to those larger sizes (1/2", yikes; I assume those would go with correspondingly gigantic airframes), and I'm not equipped to do it. Also, the 3D prints would start getting expensive up in those larger sizes.

So I'd say the current design could work reasonably well up to 1/8" (and even then changes would be needed to accommodate larger airframes), but above that it's dicey.

I'm happy to provide the CAD file if you want to play with it. :)

Yeah, after I posted I thought the 1/2" would be pretty much out of the question--like a brick. Yes, you can send the CAD file to dixont936 at gmail dot com. Thx!
 
All four fins are filleted. Only remaining work is to attach the parachute and PAINT.

Couldn't resist a quick photo op of current status:
ImageUploadedByRocketry Forum1448331024.150756.jpg
 
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I usually paint then install shock cord and chute(low power) as they get in the way of my painting stick/model holder, however you might be using something different... good luck, hope it turns out well.
Rex
 
I will indeed do the parachute and connection of the shock cord to the front transition at the very end, mainly because I want to keep the pieces all disconnected. The shock cord is already in, bundled up and stuffed into the BT. Doesn't really get in the way of anything, there's plenty of room in there. :)
 
The sharp-eyed reader would have noticed that I almost forgot something:
ImageUploadedByRocketry Forum1448465654.833983.jpg

That is now taken care of. I use a single large lug because, like engine hooks, they just don't bother me. This is a 3/16" lug.

*Now* I'm ready to paint.
 
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I have glued launch lugs to at least three painted models. :-/

Wes
 
Waiting for painting opportunities is maddening. Dunno what I'm going to do over the winter. In the meantime, I have to get everything masked.

Here's a sight I hoped not to see:
ImageUploadedByRocketry Forum1448850132.401290.jpg

I painted the transition and then masked it, hoping to leave it that way until the rocket was finished. Unfortunately, I forgot to sand the primer on the BT before doing this, so the process of sanding the BT frayed the edges of the masking tape on the transition. So I needed to rip it off and redo it, a bit more challenging with the fins in place. Nonetheless I got it done without too much fuss:
ImageUploadedByRocketry Forum1448850162.412508.jpg

Finally, I needed to mask the forward transition. This one was tough, and I realized that not painting the whole thing green (including the fins) was a big mistake (sorry Tim, I should have listened). I did my best with the masking, but I am prepared for results to be less-than great (although I won't find out until the very very end, because that masking is staying on now until the lettering and striping is *finished*.) In fact, I am prepared, in the case of really bad results, to completely rebuild the forward transition/payload assembly, and do it *right*.

Truth be told, I am already feeling a strong urge to build this whole rocket again, correcting all the mistakes I made this time. But I should finish this build first. :)

So here's my masked-up forward transition (still need a quick wrap of blue tape around the shoulder to completely cover it up).
ImageUploadedByRocketry Forum1448850141.884476.jpg

And now I wait for painting opportunities. :mad: This thread is about to get really slow for a while.

By the way, I'm really digging these papered fins. They look and feel nice, and incredibly strong. I had thought about trying to do through-the-wall fins here, which would have been very tricky given the design, but I now can see it was totally unnecessary. I can't imagine anything happening to these fins, short of getting run over by a car.
 
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If you're worried about painting in the cold, don't be... Just keep everything indoors, step outside to spray the paint, then bring everything back in to dry. It'll be fine. Just to be sure, I dangled mine over a heater. Helps it to dry out more evenly anyway, so no worries. I've done this on 4" large rockets which take several minutes to get down a light coat with no problem. Certainly shouldn't be a problem with this...
 
The cold contributes, but I have all manner of issues constraining my ability to paint this month. I'll just have to be patient, but with this paint job requiring several steps, it's going to take me longer than I'd like to slog my way through the whole thing. If only I had started this about a month earlier I'd be in much better shape. Oh well, it'll get done eventually.
 
Got a good little opportunity to paint, so on goes the black night metallic. The transitions are masked off, the nose cone safely in storage, and everything else gets the black.

For the forward transition/canard assembly, I shot it with key lime first. Why? Well, I realized that despite my best efforts, I could not be quite certain of the alignment of the masking tape on the transition and the edge of the green paint. My concern was that the black coat could get under the edge of the tape, and then the silver would be blocked out, which could have yielded a very fine black line at the edge of the mask. At least, it seemed to me like a theoretical possibility. So I thought the shot of green would prevent that. Excitingly, I won't know how well it all worked until I remove the masking tape, which is at least after the silver coat.

About 10 minutes after the key lime I applied the first black coat, and did a relatively bad job with it; I had some horrible runs. The metallic paint is quite thin compared to the 2x Painter's Edge, and it really demands a different technique. On the second coat, I did a reasonably good job correcting the mistakes, and the result, while far from perfect, is at least "good".

ImageUploadedByRocketry Forum1449355913.655132.jpg ImageUploadedByRocketry Forum1449355923.997534.jpg

The black night metallic is an interesting color; it's very metallic, but it gives much more of a very dark gray appearance, rather than black (I suppose it looks black in the pictures, though). Won't really be able to judge the whole thing until it's done; right now it just looks like a whole lotta black.

I am hoping for an opportunity to to the silver fins next weekend. I fully expect the silver paint to give me a lot of grief.
 
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silver paint(for me) usually turns out looking like natural aluminum. also takes me 3-4 light coats to keep it from running (that and the human rotissary bit :)). just sort of mist it on, you definatly don't want to try and hurry the process. it also shows every flaw (worse than gray primer). may random factors work in your favor.
Rex
 
Ayup, good luck with the silver. It's never fun to work with for me.

Nate
 
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didn't want to jinx things by saying it directly :), likewise no comments about your current progress other than the rusto metallics darken as they dry, so let them dry before judging whether to apply another coat.
Rex
 
The (mostly) dry black paint is looking pretty good I'd say. There are a few little imperfections here and there but I'll deal with those later. The fins are a bit messy, but that's just the base coat for the silver so I didn't try to get them too perfect. I'll probably give them a very light fine-grit sanding before putting on the silver, which should be this weekend, when the silver should go on.

I guess it's time for me to order my paint masks from StickerShock23, for the lettering and the stripes, although I'm not sure if I'll get to do all that stuff before the new year.
 
Neil, I was hoping to see this rocket this weekend,,, oh well, there is always next month.
She's coming along GREAT btw.
 
Neil, I was hoping to see this rocket this weekend,,, oh well, there is always next month.
She's coming along GREAT btw.

Thanks. In one more week I could have brought it there, sans lettering and stripes. Ah well.

The very prolonged process of painting (and this rocket has a couple more steps than usual) is frustrating to me.

I will get it to Godlewsky Farms... eventually.
 
Masked up and ready for silver paint.
IMG_3441.jpg IMG_3440.jpg

Doesn't look like much. After the silver paint I will be removing all the tape, and we'll get a good look at the thing. Then I'll re-mask as necessary for the final Key Lime decorations.

Oh, and I ordered my paint mask from StickerShock23. Feels unlikely I'll get to it before heading off on vacation, but maybe....
 
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Three light coats of silver paint when on the fins today. It actually went pretty well, *mostly*...

Here are the main fins:
ImageUploadedByRocketry Forum1450056067.167901.jpg
The reflectivity patterns aren't from the photo, they're actually there in the paint. It seems as if on the final coat, I got some parts "wetter" than others. Unfortunately I didn't discover this until a bit later, so now I'll have to wait a few days and then apply one final coat that will hopefully smooth things out. There's a strong urge in me to just leave it the way it is, but it's just too noticeable and I really won't be happy with it if I don't at least try.

The good news is, other than this one problem (?), the silver looks pretty good.

The canard assembly is another story. The fins came out perfect (I think), but my masking job was apparently not only "not perfect", but instead it was "perfectly awful". I'm not quite sure how it was so bad (I spent a good bit of time doing it as carefully as I could), but I got rather massive bleeding of the black paint under the tape, not only along the fin roots but even around the transition-BT joint, which I thought was the "easy" part. Here is a picture that does not show the worst of it, because I'm too annoyed/embarrassed right now:
ImageUploadedByRocketry Forum1450056056.931264.jpg

The good news is you can see the fins look nice; the bad news is all that paint bleeding. After the silver has had some time to dry, I shall undertake removing (or covering up) all the unwanted black, which should be "fun". I said before that I'm prepared to completely rebuild the payload/canard assembly, and I might just have good reason. I will, however, finish this one up, and probably fly it, before (eventually, maybe) replacing this part.

I think what got me was trying to keep the tape conforming to the various compound curves; I knew it was tough but I truly am surprised it's as bad as it is. I certainly hope I did a better job around the main fins, but I won't know until after I apply my last silver coat.

Who's idea was this ridiculous paint scheme again??? :bang:
 
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do not try to mask off the silver. it will not turn out well. instead, I would try spraying some of your key lime into a plastic cup (you want liquid paint for this) and with a small brush attempt to 'touch up' the transition.
Rex
 
I was gonna try to scrape off as much of the excess as I could with an xacto knife first, and then do what you described. I'm not going near those fins with a spray can again.
 
Is it possible that some careful wet-sanding of the main fins would even out the finish? I might try it with one fin just to see, because there's no guarantee that even if I apply another coat I won't make things worse (or at least not make it better). There'll be Future on it all at the end, so I'm not worried about restoring the gloss.
 
Is it possible that some careful wet-sanding of the main fins would even out the finish? I might try it with one fin just to see, because there's no guarantee that even if I apply another coat I won't make things worse (or at least not make it better). There'll be Future on it all at the end, so I'm not worried about restoring the gloss.

For the best effect that I can think of would be to carefully sand off the affected area, and try again. Before doing that, you might want to reproduce the problem on some scrap, and test to see if it'll work.

In my experience with metallics, sanding will not even out the appearance of runs/pooling. The paint's pigments kind of float in the medium, light coats allow all of them to lay down the same, but a heavy coat (such as a run or sag) allows them to "freeze" while curing into odd angles instead of laying flat. Thus the noticeable difference.

Oh, and despite what you might think. Silver sucks for increasing your reflectivity (I'm thinking bicycles here). Instead of focusing the light back to the source, it reflects it off. Look at a silver bike at night, and you'll see it's not much more visible than a gloss black bike
 
For the best effect that I can think of would be to carefully sand off the affected area, and try again. Before doing that, you might want to reproduce the problem on some scrap, and test to see if it'll work.

Ha ha, no way I'm sanding off all the paint. I'll take a crack at improving it through one means or another, and at some point say "good enough". It's not actually bad right now, but I want to see if I can get it more even.

Oh, and despite what you might think. Silver sucks for increasing your reflectivity (I'm thinking bicycles here). Instead of focusing the light back to the source, it reflects it off. Look at a silver bike at night, and you'll see it's not much more visible than a gloss black bike

Yeah, I wasn't thinking of improving reflectivity here, just like the way it looks.

On the other hand, there's a good reason why I generally paint my kits according to the face card, and don't try to invent my own color schemes. :)
 
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another light coat should take care of the odd look of the fin(s). future is the way to go to clear coat them, everything else just makes silver look blah.
Rex
 
Well this is cool:
ImageUploadedByRocketry Forum1450661316.326079.jpg

My first ever stickershock23 order. Top is paint mask for the name (7/8" text), bottom is some diamonds for the fins (as shown in OR renders previously) in black vinyl.

Sadly, it all must wait until after New Year's, when I will be able to resume.
 
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The fins look great - they look sharp as in big x-acto blades sharp.
 
Applied some more silver to the fins, seems to have evened things out for the most part. The first one I put on too heavy, and watched in horror as it ran before my eyes. By the time it was done, though, it had sufficiently leveled out that I'm probably not gonna touch it.

Here are two of the "good" fin faces. It is hard to photograph silver paint, but this at least shows that the reflectivity is consistent across the fin area.
ImageUploadedByRocketry Forum1451792415.202335.jpg

The fins do not look as good as this from close up, but this paint job was already shaping up to be a "looks good from 10 ft away" sort of thing anyway. New Years resolution for 2016: become less of a spaz at finishing.
 
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