Spin-Casting: A Better Way to Make Rocket Motors

Lathe Safety Resources:
^^^ Just as with solid rocket propellant - learning to use a lathe is best done with a mentor in person - find an older machinist familiar with the risk who can help you see your blind spots

For more info:

[BPSspace]

Thanks to Incogni for sponsoring this video! To get an exclusive 60% off an annual Incogni plan, use this link: incogni.com/bpsincogni

[BretHall]

My favorite saying about the dangers of a lathe came from my stepdad, who said that a lathe would rip your arm off and slap you with it twice before you could react.

[RocketVlogs]

I'm in a BPS video. Calling my mom to tell her I made it rn

[Volkeu]

I find myself obliged to point out that the mixture name "Mystery Goo" is an excellent KSP reference. Even if not intended.

[curtiscapdeville]

I work for Northrop Grumman where we make the SLS solid rocket boosters, and my job is exactly this, mixing liner material to line a steel casing with. We do it in over 200 lb mixes at a time. So I am very knowledgeable on this process and the process you have developed for application is very clever. We do something similar with smaller motors called slush lining, which is essentially what you're doing here but we don't spin at high speed until it cure. Another thing to point out, yes you are using this material to chemically bond the propellant to the liner, but with how thick it is, you're creating your insulation at the same time, very smart!

[FailSpace]

You know it’s a good day when John Joseph Bizzlington Jr. II, First of his Name uploads

[USWaterRockets]

This brings back memories! Before 3D printers were a thing, I used to spin cast silicone molds for nosecones with a perfect parabola profile. You just spin in the vertical orientation and you have gravity combined with the spinning "centrifugal" force acting on the liquid silicone creating the nosecone shaped void. I'd then use resin in the mold (with a cap on the open end) and do rotational casting to make the hollow lightweight nosecone casting at a uniform thickness. Rotational casting is just spin casting on 2 axes at the same time. I made a rig out of PVC pipe for this that worked well, but you can also just do it by hand because the resin cures pretty fast. This content is top notch!

[sotrh]

One video idea that I personally would be interested in would be how do you properly dispose of the varieties of waste that come from making rockets. I'd imagine chucking a failed batch of propellant in the dumpster would get you in trouble.

[danielchan]

God bless Borbo the wizard, good to see he's doing better now

[KegRocket]

Joey B so committed to the aesthetic he even polished the sample tubes!

[funnyyylock]

I really appreciate your divulgence into safety. alot of people do not understand how dangerous heavy machinery is. ALWAYS ALWAYS ALWAYS Look out for yourself and your coworkers guys.

[muttenmagroo]

Reliant Robin is a reference to Top Gear that strapped one to a rocket.

[quaker]

I really enjoy how you don't make just one large video focusing mainly on your successes, but you make all these separate smaller videos about your failures as you approach your successes. Really shows how much effort it takes to do this stuff and it feels like we're all on the journey with you.

[Hagop]

Many people do not take safety seriously enough, so thank you for taking the time to stress the importance of it.

[PrebleStreetRecords]

I do a lot of lathe work for gunsmithing, and there are a couple things I use that could be scaled up to help here.
You can get live centers that are truncated cones, intended for doing external turning work on hydraulic pistons and such. I have a set ranging from 2-3” up to 10-14”. Using one of those instead of a steady rest would allow you to apply force from the tailstock to keep any more complex casting plugs or other assemblies from moving in the tube. It could also help hold the extrusion in-round, particularly with something like a six jaw chuck.
Also, I have to work with long reamers for barrel making, so I have a system to introduce coolant and lubricant through the spindle bore and down the length of the barrel. I bet you could take a similar approach to feed the casing material (or propellant) into the casing from “behind” while the lathe is running, reducing mess. You could even make the chuck-end mold plug part of the system, with a bearing surface for the goo tube to rest in, keeping it from snagging on the moving case.
This is an amazing project, you’re doing incredible work, and also communicate what’s going on clearly. Best of luck!

[shere_kan]

Just gotta say that you are among the 2-3 youtubeurs that give me the most excitment when a videos drops out, along with Stuff Made Here, EZ composites, and Primitive technology.

[COSMOSIS]

BEPIS SPACE BACK WITH A BANGER OF AN EPISODE!!!

[TheNerd]

At 4:05, I feel like phrasing it as F=mω²r would make it more clear why increasing the radius increases the centrifugal force.

[TheClumsyFairy]

I wonder how many people are going to try and correct the spelling and pronunciation of 'hygroscopic', and say that it should be 'hydroscopic'.

Lets just say that I very nearly did exactly that, but decided to google it to make sure first, and I'm so glad I didn't make a total fool out of myself. I just got my most favourite feeling, that of being wrong about something I believed for the longest time, and being corrected. It's even better when I do it to myself <grin>.

[arunoe]

dang, you really went crazy with the animations in this one lol. looks good!