What did you do rocket wise today?

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This first foam/fiberglass/Bondo nosecone was a huge learning experience. It's not pretty, but it's shaped well enough and solid. It'll go on the upscale (5.25" diameter) Big Daddy and I'll take what I learned and make another for the Doorknob. But, I had to put it on the Doorknob to see what it looks like😄

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Looks good.
How "out-of-round" is it? I can't imagine not using a lathe to make a nose cone.
 
dry fit my Madcow Cricket, definitely going to need to modify the nose cone. Out of the box the motor tube is almost touching the bottom of the nose cone. going to cut off the bottom of the nose cone and recess a bulk plate. that should give me the space I need.
 
Opened 10 Goblin kits, pulled out the MMT parts and started building 10 MMT assemblies in parallel. Not too bad really. Hardest part will be to attach the fins on all 10. I'll have to do that one after another since I only have 1 set of fin guides.
 
Opened 10 Goblin kits, pulled out the MMT parts and started building 10 MMT assemblies in parallel. Not too bad really. Hardest part will be to attach the fins on all 10. I'll have to do that one after another since I only have 1 set of fin guides.
you gonna do 'em all yellow n black? was thinkin' it would be cool, if i had a bunch of the same simple kit, to paint each one with another rocs scheme, ie one like a max, one like a bertha, one little joe 1, one yankee, whatever.
 
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you gonna do 'em all yellow n black? was thinkin' it would be cool, if i had a bunch of the same simple kit, to paint each one with another rocs sheme, ie one like a max, one like a bertha, one little joe 1, one yankee, whatever.
I'm going to prime them all with flat white. Christmas they'll be given to nephews, nieces, grand-nephews and grand-nieces along with markers. They'll decorate them and then after dinner, we'll go out to the back-40 and launch them on D12s. I'll end it with launching my MDRM on a 29mm G.
 
I sanded the spackling compound , and this time took your advice and used a hard foam sanding block which solved my problems. The airframe is smoother than a newborn babies butt. 👍
If you have any areas of significant build up that may need protection, such as fillets, apply thin CA to the spackle and it will harden significantly. Add CA after sanding, of course.

Jim
 
called my friend in Ky that I went to school with to see if he could make the 3 small decals I need for my Delta II restoration but I struck out. :mad:
 
Maybe. About 11.34 ¢/oz with post-1982 pennies, 9.12 ¢/oz with pre-1982 pennies. (With 1982 pennies, you have to weigh them individually.)

That's pretty cheap, but you can usually pick rocks up off the ground for free.
 
A ball on a stick? Some people use fondant tools.
Do you object to me calling a "ball on a stick" a tool? :p

Yes sir, fondant tools are an option.... :) But I think the fondant tools are a compromise, at best.

I commented in my build thread on some of the reasons I want to make a purpose built tool. I tried working with them back when I was building high end speaker cabinets, etc. (My then wife was a culinary arts competitor and had every baking tool known to man.) Short handles, big diameter handles, less visibility, less reach, no lubricant needed for Delrin balls, clean up easier...

Not to mention, I have a theory that I am testing out.... I believe that we use wayyyyyyyyyy too much epoxy on average to complete a build. I am trying to build a skills and tool kit to calculate and apply the "right" fillet in every circumstance, based on purpose, position, visibility, supporting bonds, et al.

Most of the "extra" adhesive is either tooled off and wasted, or worse, it is allowed to cure ON the air frame in a location of way in which it is not contributing much more than weight. Using too large a fillet, or the wrong epoxy or filler, or using the wrong consistency, et al, ad nauseum. ;) So much to go wrong. So most folks over-use adhesives to cover for inferior engineering and poor construction technique....

And in the case of external fin fillets.... too much emphasis on aesthetics as a priority over aerodynamic and structural concerns. Aesthetics, IMO, should reveal themselves from elegant engineering and skillful production/construction.

I AM an over-builder.... I admit it. But I am also a weight weenie.... I don't want weight in the air frame that does not have a purpose.

So I am studying.... and I will be testing my tools and assumptions as I build. What works, I will keep. What doesn't I will change/improve/eliminate. :)
 
Saw this video on YouTube last night, and am trying to figure out what kind of applications I can use it with in regards to rocketry/rocket building....



Redneck 3D printing. ;)

Seriously, apart from the obvious safety concerns (fumes, how not to use a knife) that's interesting stuff.
 
Saw this video on YouTube last night, and am trying to figure out what kind of applications I can use it with in regards to rocketry/rocket building....



I've made fillets by laying down a "bead" of baking soda then dripping thin CA onto it. It has to be thin CA, and it's really important to keep the tip of the bottle out of the soda.
 
Pictures please?
Hmmmm.... that might be a trick.... Let me look... <rummaging through 30+ years of pictures...>

<much later>

Nope... I do not have any of the imagery from my audio days... Apologize, but getting away from my last ex-wife cost me a lot more than money. Seems my audio/home theater stuff was part of that cost.
 
Tried to figure out dipping the Quickburst Conductive dip. But something about my dip is not right. Has to be consistency. No wait... is it the wire?? I have no clue. And what few starters I have made, once dried, range from a good 3.x ohms to a not so good 9.x ohms. Tho using a 12v gel cell both snap off in about 2 to 3 seconds.
 
bummer, did you build subwoofers?
Yes sir... I had a business partner a LONG time ago, who worked for Vandersteen Audio building/designing crossovers for their super high end stuff.
I benefitted from his experience, et al. I spent years designing and building my theater. My last sub was a passive 15" down-firing behemoth of 425 lbs if rigged for full volume. When the theater was closed up (sealed really), you could ACTUALLY blow the windows out of the front of the house if you turned the volume up too high during the peak of the U-571 depth charge attack. After the second time, I had to institute a "No full seal on the theater, UNLESS I am present and in charge of the controls." :)
 
My last sub was a passive 15" down-firing behemoth of 425 lbs if rigged for full volume. When the theater was closed up (sealed really), you could ACTUALLY blow the windows out of the front of the house if you turned the volume up too high during the peak of the U-571 depth charge attack. After the second time, I had to institute a "No full seal on the theater, UNLESS I am present and in charge of the controls." :)
Check out the current King of all subwoofer drivers when you get a chance:
https://stereointegrity.com/product/hs-24/
 
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