I have CAD and a 3D printer

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dr wogz

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I'm doing a scratch build with a non standard tube dia. And I thought: "What am I gonna do for a nose cone?" CRs are easy, but nose cones can be tricky.

And low & behold, I have CAD, I've been doing CAD designs since we stopped using pencils! :D and I have a 3D printer at my disposal!

So, what can I whip up in about 10 minutes?!

dia. is roughly 1.5" by 3.75" long with a typically wall of about 0.030" (dims aren't set yet, need to verify & tweak) but it's a start. (And there's about a 1/2hr left in the day..) I'll be adding a #8 eye bolt in the protrudy hole thingy..

Yes?

No?

PLA, red or silver..

pgsnc1-a.jpg


pgsnc1-b.jpg


pgsnc1-c.jpg
 

jnobels

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Printed vertically or in two halves?

If vertical, you probably want to print that in two pieces. It could very weak at the transition from the sleeve to the cone. I did an av bay with a step transition like that in pla which just pulled apart. That pretty rounded detail on the bottom will also be mostly lost due to the supports that have to be printed. You also can’t add removable interior support.. it’s gradual enough you probably don’t need it for the tip though. It might be ok if you print it horizontally in two halves (depending on the size of your printer of course)

I like doing my cones in 2 to 4 parts - all vertical. Tip, cone, sleeve and either a sleeve base, or I mount the shock cord to the tip.

ABS all the way too. It’s not that scary. I started with PLA but it gets too soft with any kind of heat and abs can be finished and welded with acetone (or strengthened with an acetone abs slurry). Abs also sands much much easier. For decorative parts, PLA is less of a hassle for sure.






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dr wogz

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Thanks all,

Yeah, PLA, in one shot.. I've beefed up the transition part, so it should be OK. I've made it long enough that the over hangs are minimal. It's the work printer. And no, no ABS yet (Fumes & all). I've run a few rolls thru it, so I have a pretty good idea of what I'm expecting.. (Fusion3 360 printer if you have to ask..)

Facets, because I can! :D
 

dr wogz

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Here's the rest of the build.

It's the motor tube form my L2 cert motor. Something like that, you need to keep & honor in some way! Custom red 3D printed NC, TTW fins, and all the usual "Estes type" bits & methods.. Nothing too fancy. No finish, I like it 'raw'.. I put it in OR, to get the fin shape & get a template. that's about it...

Flew on a D12-3.. forget the weight, and didn't' bother to put my Alt in it..

It went up, it came down, ready for another day!
 

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jnobels

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Ha Cool!

The ABS fumes are overrated. I run my printer in the shop (sometimes for days on end) and don’t notice any smell at all. I wouldn’t run it in a small apartment tho. Might depend a bit on the filament brand and temps.

I launched bunch of mid power birds I built over the winter on Sunday all with everything but the fins and tubes printed (nose, rings, rail guides, couplers, lugs, etc) and they all returned to sender in perfect shape.
 

vic20owner

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Agree the ABS fumes are nothing.. I run my printer right next to my desk and it runs all day.

I sand and fill my ABS nosecones with drywall mud, and then prime and paint. They come out nice and glossy. You can also boil acetone and dip the nosecone in the fumes (not the liquid) in the pot to smooth them out, but be careful not to get the shoulder into the fumes or it will get rounded off.
 

lakeroadster

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You can also boil acetone and dip the nosecone in the fumes (not the liquid) in the pot to smooth them out, but be careful not to get the shoulder into the fumes or it will get rounded off.
Extreme care should be taken if anyone is contemplating boiling acetone...

"The most hazardous property of acetone is its extreme flammability. At temperatures greater than acetone's flash point of −20 °C (−4 °F), air mixtures of between 2.5% and 12.8% acetone, by volume, may explode or cause a flash fire. Vapors can flow along surfaces to distant ignition sources and flash back."

https://en.wikipedia.org/wiki/Acetone
 

cwbullet

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Care to share the file? I will have a printer at the end of August or early September.
 

vcp

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Agree the ABS fumes are nothing.. I run my printer right next to my desk and it runs all day.
I'm sure the odor bothers some people, but I rarely notice it. If I stick my head in the printer enclosure I can get a snootfull of it, and when I had a printer is a small office, if I left and returned I could notice it in the air. Never seemed especially bad to me, and I think my sense of smell is reasonably intact.
 

cwbullet

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Don't Breath in deeply. I am surely huffing the gas is deleterious to your health.
 

vcp

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It's good to be careful, but perspective is good too. Compared to common ABS/PLA, you literally encounter more hazardous airborne pollutants in your home by frying a steak**.

SLA resins are nasty though.

Probably the main reason that I don't usually notice my printers is that both the Replicator (upgraded) and DaVinci are fully enclosed. The new upgrade in process on the Replicator will give it new enclosure panels, so the old will go to enclose the CTC when I get it running.

** Though this is a false equivalency in several respects: You don't fry a steak in a bedroom or office where printers are sometimes located, or for hours, as prints commonly run. You do usually fry a steak under an exhaust hood, but usually not in an enclosure. But overall in my home, cooking odors are much more noticeable than the printer.
 
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OverTheTop

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I have tried painting on acetone and also using vapors. It's ok.

I usually use a coat of Loctite 401 CA (apply by hand), sand, CA, sand, CA, final sand. Lots of ventilation please! Nice and glossy. Paint sticks well enough for me. Have not had any troubles, but haven't painted much either.
 

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I had a cone printed to see the quality. If came in 4 sections. I glued it together with plastic weld 2 part epoxy.
 

OverTheTop

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For gluing ABS (cracked NC parts) I just use acetone. If a filler is needed I dissolve ABS fillament in acetone after the basic gluing is done. I suspect it is stronger with the application of acetone after being cracked.
 

cwbullet

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I used either Blender and Fusion 360.
 

djkingsley

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I attended the East Coast RepRap Festival (ERRF) a couple weeks ago and met the group responsible for 3D Gloop they have product for gluing printed parts and surface finishing for several common material types. I was impressed by the product demonstration and decided to back their kickstarter campaign. I also picked up several different types of build surfaces and so far I am a fan of the GeckoTek product. I have used it with several types of PLA, PETG, and ABS with no warping and the parts pop right off after the plate cools. I was also very impressed with Slice Engineering's high temperature Mosquito hot end.
 

vcp

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Uhm, anyone know how to upload an SLT or G-Code file? (Do I need to .zip them? .rar?)
You're right, it doesn't allow .stl files. We should get the forum masters to fix that.

You could put it here and point to it:

There was this, started some time ago:
Rocket CAD Repository -- I'd just about forgotten about it myself.

The forum doesn't allow .scad files either, and probably many other CAD formats. But .scad files are just text, they could be renamed as .txt, then changed back after downloading. Come to think of it, ASCII .stl's are just text too, I believe. Could probably do the same, rename as .txt, and rename back to .stl after download. (Note, there is a binary .stl format - you'd need to select ascii when outputting the file.)

There, I've attached an .stl renamed as .txt. ... and downloaded it. Renamed and opened fine. That's clumsy, but works.

Oh, but heck, it does allow .zip files, good to zip .stl's anyway as they can be large and will compress a lot. (a bit dangerous tho, I wonder if the forum sw scans them?)
 

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cwbullet

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That works. I will ask about stl files.
 

vcp

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Uhm, anyone know how to upload an SLT or G-Code file? (Do I need to .zip them? .rar?)
Oh, and as as for .gcode files, they are just text too, so the same would apply. However exchanging gcode files is not very practical. It would only work if you had identical printers and identical recipes (speeds, temps, placement, filament, etc). Also some printers use .3w or .x3g files (specialized vendor or firmware specific versions of gcode - there may be others). It would be better to exchange components at the .stl level and note any necessary special slicer settings. [e.g. right now I'm printing single-layer transitions that must be printed in spiral mode - the .stl will look like a solid and spiral mode must be selected in the slicer to make sense of it.][... and of course slicers are different too - some will name spiral as 'vase' mode, and I don't know that every slicer will do either.]

Of course you can also exchange CAD files, but that only works if you are using the same CAD package or programs that have mutual import/export abilities (never guaranteed). You have to do it at the CAD level if you expect the recipient to be able to alter the model. But .stl is the point of convergence that is nearly universal for exchange (and to some extent .stl's can be modified by the recipient as well). At the .stl level there are also .obj and .3mf filetypes, but they aren't nearly as common. 3mf may be a contender as a new standard (.stl is really limited).

Someday there may be a magical time when all printers speak the same universal model language - but I'm not holding my breath. (Hey, it sort of happened with 2D text/graphics and .pdf files, so it may happen in my lifetime.)
 
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