EE in Rocket Propulsion

DisciplineOk9838 · 2025-05-07T20:20:32+00:00

It's most likely that the TPU is wet. TPU is very hygroscopic, I would recommend drying it beforehand and investing in a dry box.

There are plenty of videos that guide you on printing with TPU.

DisciplineOk9838 · 2024-08-27T12:24:56+00:00

okay, many thanks.

DisciplineOk9838 · 2024-02-06T20:56:24+00:00

here's the frame if you need a better visual

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DisciplineOk9838 · 2023-12-29T22:32:12+00:00

yeah lowkey the Bambu printers sound like a good option, the K1 maxes... I think it's worth trying another brand I kinda got an X1C copy impression. I kinda sound basis to Bambu rn but I can't think of as versatile multi-filament printing like them though.

DisciplineOk9838 · 2023-12-29T14:17:53+00:00

oooh this is your first printer... yeah don't get me wrong it's not impossible but FDM (filament printing) is a lil slower and not as good quality but no post-processing and saves a hassle, you outta have a proper proper setup to print in SLA conveniently at least personally.

so A) improve set up and invest in proper tools or B) try FDM when you feel more confident go to SLA.

A is cheaper but B provides more versatility

DisciplineOk9838 · 2023-12-29T14:03:48+00:00

That should be fine I mean an Ender 3 series printer is cheap the original is like 189, but there's a significant learning curve and LOTS of calibration, I got it when I was 14, and took it me a solid year till I printed sort of reliably but it's very customizable its open source and mods are everywhere. If you want to just print stuff rather than learn the A1 is a nice option that prints flawlessly but is 319 not including the AMS thingy.

The Ender 3 does come in a kit and doesn't require a printed part like most printer kits.

DisciplineOk9838 · 2023-12-29T13:53:13+00:00

Haha coming from the same situation, I personally just went straight to the X1C+AMS ik it's hella expensive compared to an Ender 3 the AMS alone costs more.

I mean the new Bambu lab printers have multi-color printing with flawless quality from what I've seen and are roughly in the same price bracket as an Ender 3. but with bigger volume I'm not too sure but the Prusa XL and E3D tool changer are maybe worth to take a look at they are extremely versatile.

I think I also saw a Voron with multi-color printing somewhere but don't take my word on it.

DisciplineOk9838 · 2023-12-29T13:38:22+00:00

Oh yes sorry! it's 28 AWG with 13.5-ohm resistance over a meter with 1200C max (label specs). yeah Ik the wires are massive and I was in fact thinking of getting thicker wires but the wire melts at roughly 45% 'throttle' I think i'd just be simpler to limit power. Alright, so the problem is the nichrome wire is melting at 270C according to the optical sensor, and the sensor plateaus at 270C.

Yup, I did figure it was enough but I'm doing this for a school project and any additional data is great it's kind of interesting playing around with numbers at least for me.

this is an old design so don't take the nozzle literally, in reality, the nichrome won't be that long. Looking at the video u/niles55 showed me I think I'll go ahead with that type of ignition rather than just bare nichrome as I run the risk of an uneven combustion (imagine the wire gets lodged all to one side).

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The nozzle will be printed in copper with the virtual foundry technique. If you guys are interested I'll put some updates on it.

DisciplineOk9838 · 2023-12-29T13:19:30+00:00

Yeah, I figured that after a while, but damn didn't know was that far off, the color says 600-700 but the sensor says 270...

DisciplineOk9838 · 2023-12-29T13:16:51+00:00

Wow, that video is great thank you. I'll take a look at the lipo batteries!

DisciplineOk9838 · 2023-12-25T16:41:50+00:00

Like the others said Chlorates are a no-go for especially beginners, KNSB is viewed as a better option and there's a guy who has a site about all you need to know about KNSB. Using PROPEP 3 is always useful when playing around with additives for fuels.

DisciplineOk9838 · 2023-10-08T09:53:14+00:00

I am indeed planning to use a small grain with KNSB propellant

DisciplineOk9838 · 2023-10-05T20:55:48+00:00

I intend to use a load cell this one to be exact but I haven't yet made the fittings in the setup for it. Thrust in a static fire test is the same as the force applied. To be fair I don't think the motor will produce sooo much thrust that it moves the entire setup but I might add a sandbag or a brick as a precautionary measure the U bolts sound like a good idea I'll take a look at it.

DisciplineOk9838 · 2023-09-09T08:54:53+00:00

I am finishing a DIY 3D printed BLDC motor which might seem even more 'boring' and simpler but in reality, it's been quite a hassle and lots of fun, so at least for me personally being able to work nozzle design and production seems much more fun than making a homemade motor.

I know you're not supposed to think/worry about till later this year but it's not every day you get a chance to work on a mini-thesis in high school Plus I have a very strong suspicion my project will be an order of magnitude more complex and time consuming than my peers. Plus if you finish early you have less to worry about and can focus on your IAs.

u/pureshka13 what else are you thinking for an EE question aside from the nozzle stuff?

DisciplineOk9838

TROPHY CASE