Booster Shot: another dubious build thread

[neil_w]

That came out great! I love how your finished pictures just look like slightly glossier versions of your pre-build rendered artwork.

Always a fun exercise.

 

[jqavins]

One challenge for me with clusters is that they often/usually require interesting centering rings, which I cannot make myself. I do have a 24mm/BT70 Deuce motor mount kit in my supply box that I've been debating what to do with for a long time.

Balsa Machining may be able to help here. They have a pretty wide variety of cluster centering rings.

Also, anyone with a laser cutter or 3D printer can make them, and I'm sure that there are people here who'd be glad to. (I would if I had those things.)

 

[neil_w]

Also, anyone with a laser cutter or 3D printer can make them, and I'm sure that there are people here who'd be glad to. (I would if I had those things.)

Yes, I have been so helped before (e.g. @Sandy H. made the weirdo rings for Shear Insanity for me). But it's annoying and slightly uncomfortable not to be able to do it myself, in case I need to iterate.

 

[jqavins]

I understand. After my last post, I've been browsing laser cutters on the web, wondering how cheap I can go and still get something worth having. I'd rather spend $300 on a usable machine than waste $150 on a machine that doesn't do what I need.

 

[neil_w]

I understand. After my last post, I've been browsing laser cutters on the web, wondering how cheap I can go and still get something worth having. I'd rather spend $300 on a usable machine than waste $150 on a machine that doesn't do what I need.

The last Apogee POF had some (I thought) good info on laser cutters. My impression (along with previous discussions on the forum) is that $300 really won't get you where you want to go.

 

[jqavins]

That's what I was afraid of. There are some in that ballpark that look, based on what I can tell, like they would do, but I need some qualified advice.

I'm a couple three years behind on PoF, but I'll put the current issue at the head of the queue.

 

[jqavins]

OK, yeah, the 10 W machines that claim to cut 4 or 5 mm plywood may not be as good as they are made to sound. And I was thinking of taking the 20 W version of one of those, still under $300, and now I have major doubts.

One thing the article reminded me of is that a CNC router may be a good option.

 

[Azamiryou]

anyone with a laser cutter or 3D printer can make them

... or a jeweler's saw for thin stock, coping saw for thick. Scroll saw or saber saw if you prefer a power tool.

 

[les]

Another great design and fantastic implementation!!!
I envy your skills.

 

[neil_w]

Final todos:

• Shock cord and parachute hookup

Done. Well, close enough... I'll have to steal a 12" parachute from another rocket when needed.

• Paint touch-up on launch lug

Done.

• Adjust fit on booster. It's too tight again, which is very annoying.

Done.

Sanded off the paint on the front centering rings (I had meant to mask those off before painting but forgot), and found that a bit of talcum powder is enough to make for a smooth release.


I also applied Future on all the decals.

And that makes it official. Up it goes...

 

[ac2fv]

Love it! Dragon Rocketry needs to upscale this to a 3" or 4"!

 

[mjennings]

Beautiful work, hope you can get some great flight pictures to share. On the subject of laser cutters my local library system now has a glow forge cutter as well as other toys. Might be worth an ask at your library if any in the area has fun toys.

 

[lr64]

Excellent.
I'm wondering if the markings would be accurate if you labeled them as "pint" instead of "mL". ;-)

 

[BABAR]

Excellent.
I'm wondering if the markings would be accurate if you labeled them as "pint" instead of "mL". ;-)

It’s a NEEDLE , not a British Pub Dart!

 

[neil_w]

Excellent.
I'm wondering if the markings would be accurate if you labeled them as "pint" instead of "mL". ;-)

Ha!

Well after doing a bit of math it looks like each graduation is fairly close to 1 deciliter... so I guess I could have used "dL" instead of "mL"... or marked the graduations 100, 200, 300. Next person who builds one can fix it!

 

[mbeels]

It’s a NEEDLE , not a British Pub Dart!

Ha!

Well after doing a bit of math it looks like each graduation is fairly close to 1 deciliter... so I guess I could have used "dL" instead of "mL"... or marked the graduations 100, 200, 300. Next person who builds one can fix it!

Or the next person can take the opportunity to do a "L" upscale!

 

[BABAR]

Or the next person can take the opportunity to do a "L" upscale!

Can’t say that I am diaMETRICally opposed to that.


Although “dL” might be more to scale. We’ll keep that on the down low for now.

 

[jqavins]

Although “dL” might be more to scale. We’ll keep that on the down low for now.

Yes, we really do need a "groan" react emoji. (Maybe there is one but it's on the disabled list?)

Or the next person can take the opportunity to do a "L" upscale!

That would put it at about 3.5×51 or 52 inches. Very doable.

 

[lr64]

Ha!

Well after doing a bit of math it looks like each graduation is fairly close to 1 deciliter... so I guess I could have used "dL" instead of "mL"... or marked the graduations 100, 200, 300. Next person who builds one can fix it!

Wow! I was off by a lot. In my defense, I haven't seen pegboard for a long time, so one in the background doesn't give me much of a sense of scale. My first thought WAS dL, but I thought that might be too small. I suppose πt/π is too precious.

Yes, we really do need a "groan" react emoji. (Maybe there is one but it's on the disabled list?)

There's probably a clever emoticon for that, if anyone can invent or find it.

 

[neil_w]

Wow! I was off by a lot. In my defense, I haven't seen pegboard for a long time, so one in the background doesn't give me much of a sense of scale. My first thought WAS dL, but I thought that might be too small. I suppose πt/π is too precious.

There's probably a clever emoticon for that, if anyone can invent or find it.

It's BT60 and the major ticks are 1.8" apart, so now I did a more accurate calculation and it actually comes out to 3.8 in^3, or .62 dL or 2.1 oz. Make of that what you will.

 

[jqavins]

What I make of it is that I'm glad you made that correction. I made on-screen measurements based on the BT-60 OD and got about 69 ml, meaning one of us was way off. I feel better having resolved without having to call you out.

 

[NTP2]

Also, anyone with a laser cutter or 3D printer can make them, and I'm sure that there are people here who'd be glad to.

Yes, I have been so helped before (e.g. @Sandy H. made the weirdo rings for Shear Insanity for me). But it's annoying and slightly uncomfortable not to be able to do it myself, in case I need to iterate.

why not get a 3D printer? They are pretty affordable.

 

[BABAR]

I like all your builds, but this one really grabs the eye, looks great, and has an intrinsicic fun factor.

Wish you two straight trails, short walks, and hopes you do NOT pull a Simone Biles and stick the landing.

 

[neil_w]

I like all your builds, but this one really grabs the eye, looks great, and has an intrinsicic fun factor.

Wish you two straight trails, short walks, and hopes you do NOT pull a Simone Biles and stick the landing.

Thanks. I am a little less confident than usual about the flight worthiness of this rocket…. Whatever happens it will hopefully be entertaining.

 

[BABAR]

What’s the pad weight without motors?

What are first flight motor choices?

WHEN is first flight planned?

 

[lr64]

Thanks. I am a little less confident than usual about the flight worthiness of this rocket…. Whatever happens it will hopefully be entertaining.

Is the rocket too big for a swing test? Preferably while standing on a sturdy table in the middle of a big field of long grass. Or wait for a really windy day and dangle it on a string.

snip

WHEN is first flight planned?

Oh! I know! Whenever the surgeon general advises.

 

[Raythain]

WHEN is first flight planned?

As soon as the Phase 3 trial results are published.

 

[jqavins]

I am a little less confident than usual about the flight worthiness of this rocket.

Why?

 

[neil_w]

Why?

It all *should* work, but I have vague concerns about stability and the gap staging. I'll fly once as single-stage to confirm sustainer stability, and then a heads-up flight with two stages.

 

[lakeroadster]

It all *should* work, but I have vague concerns about stability and the gap staging. I'll fly once as single-stage to confirm sustainer stability, and then a heads-up flight with two stages.

Easy Peazy Lemon Squeezy. It's called "Booster Shot".. load that booster and let 'er rip Neil. BP motors are great at staging.​