What did you do rocket wise today?

madcow rocketry
The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Published yesterdays adventure:
This rocket is rolled out of cardboard from cases of Michelob Ultra. 101mm in diameter, 127cm long, nearly 800 grams. This is an impressive mid power flyer on these Aerotech F67-4 and G79-4 motors. Join the fun!
#ModelRocketry #MichelobUltra #Aerotech
 
o1d_dude said:
Tried the hot water bath for the epoxy bottle.

Was able to de-solidify the resin but not able to return it to its former fully liquid/syrup state. At best it resembled silly putty.

Oh, well. Lesson learned. My replacement epoxy shipment is scheduled to arrive on Tuesday.
Click to expand...

A little strange. The El-Cheapo brand (US Composites) laminating epoxy resin I bought at least 5 years ago is still just fine. It was stored at room temperature, which may make a difference. The slow curative is unchanged, and the resin itself works well with OLD (10-15 years) Fiberglast curative, at the same ratio as the can says.

Best -- Terry
 
prfesser said:
A little strange. The El-Cheapo brand (US Composites) laminating epoxy resin I bought at least 5 years ago is still just fine. It was stored at room temperature, which may make a difference. The slow curative is unchanged, and the resin itself works well with OLD (10-15 years) Fiberglast curative, at the same ratio as the can says.

Best -- Terry
Click to expand...
Love my US Composites 635 and 150 epoxy resins, a gallon typically takes me 2-3 years to use, stored year around in an insulted garage so it sees about a 40-50°F temp swing.
 
jeffjblack said:
Published yesterdays adventure:
This rocket is rolled out of cardboard from cases of Michelob Ultra. 101mm in diameter, 127cm long, nearly 800 grams. This is an impressive mid power flyer on these Aerotech F67-4 and G79-4 motors. Join the fun!
#ModelRocketry #MichelobUltra #Aerotech
Click to expand...

Awesome! Any chance you documented the process? I maaaaay be able to do something similar out of Miller Lite cases. If I start saving them now, I could have a flyer by, say, early March? :eggnog:
 
Charles_McG said:
Flew my first rocket of 2020. Great conditions. Sustainer igniter lost continuity during boost.
View attachment 406817
View attachment 406818
Click to expand...

So, I'm having fun this morning looking at the flight data v. the sim data.

flight.png
Red and blue lines are the acceleration and the velocity, red from sim, blue from the Proton.
Green and purple lines are altitude, purple from sim, upper green from Proton baro, lower green from Proton accelerometer.

The Velocity curves seem to match really well, considering the thrust difference.
And I think the sim Altitude and Proton AltAccel would match nicely, if corrected for the thrust difference.
But that flaky high baro altitude reading is a puzzler. I still think it's because my vented avbay pins are mucking up the airflow.
The baro/accelerometer difference is -sort of- proportional to velocity.
difference.png
Well, actually the square of the velocity is a better fit. And I think that makes sense.
(First 1.5sec of data, quadratic fit)
fit.png
 
mbeels said:
What was the thrust difference between the sim and actual? Do you know why the Proton velocity data has a discontinuity?
Click to expand...

Simmed at 12G boost. Measured was just over 9G.
-Edit-
I figured out that my boosted dart sim had the weight wrong (from switching motors). The New sim is just over 11G boost. And I'm thinking that the weight is still wrong, because I used longer casing and spacers for both booster and sustainer. Which would bring the sim closer still.

I don't pay -too- much attention to the discontinuities. In this case, the timing is at the stage separation event, so I assume the brief G spike put an offset the curve.
 
Last edited:
conman13 said:
Both sides will be directly reinforced first with the spread tow at 0, +/- 45 and 90 degrees. The spread tow I’m using has a binder which makes it very easy to cut exact shapes out of. Once cured and bonded on to the fin canister the t2t will be done in the same fashion. There will be ablative covering the exposed carbon as well as the leading, tip and trailing edge

View attachment 406694
Click to expand...
Are you now using the compression foam for your core and skinning with 2 layers per side of carbon?
 
View attachment 406940
For Sale: Madcow 5.5" Fiberglass Nike-Tomahawk kit.
$550.00 Includes shipping in the CONUS only.
If you live close enough for local pick up contact me for pricing.
Independence, MO 64055
 
Last edited:
Mick Kelly said:
Are you now using the compression foam for your core and skinning with 2 layers per side of carbon?
Click to expand...
No compression foam involved! The cores are G10 fiberglass and they will be reinforced with carbon on each side. The purpose is to prevent de-lamination of the hand laminations during the high velocity flight.
 

Attachments

  • IMG_4452.jpg
    IMG_4452.jpg
    121.8 KB · Views: 49
  • IMG_4453.jpg
    IMG_4453.jpg
    225.9 KB · Views: 48
Finished the paint on my 2 Cobra 1500’s
Original style is in traditional yellow/White
My up sized version is Copper/Red
 

Attachments

  • EAA08C23-4CAC-437A-A296-26E198274540.jpeg
    EAA08C23-4CAC-437A-A296-26E198274540.jpeg
    123.5 KB · Views: 74
  • 3B4EE0C2-BDAA-4384-9CFD-8B932A3A89DC.jpeg
    3B4EE0C2-BDAA-4384-9CFD-8B932A3A89DC.jpeg
    135.7 KB · Views: 75
  • 53C5BDDF-CFF2-447F-B249-471AC94D8965.jpeg
    53C5BDDF-CFF2-447F-B249-471AC94D8965.jpeg
    131.3 KB · Views: 76
I applied Stickershock23 decals to my scratch built Arapahoe E. I then airbrushed on a couple of clear coats, Pledge Revive It Gloss Polish. It's an acrylic and works well with acrylic paints. It's ready to fly on the weekend. :)
 

Attachments

  • Arapahoe1.jpg
    Arapahoe1.jpg
    188.9 KB · Views: 85
  • Arapahoe2.jpg
    Arapahoe2.jpg
    123.3 KB · Views: 85
  • Arapahoe3.jpg
    Arapahoe3.jpg
    188.9 KB · Views: 86
I finally received the Pro38 hardware I ordered in December. 3G and 6G casings, 2 spacers and a delay trimmer. Bring on L1 and L2 certs and many, many flights.
 
Got the red on my iris along with first clear on the nose cone and grey on the upper payload. Learned a lesson I should have done that first and then done the roll pattern. I missed slightly taping it off and there is a small gap. I’ll have to do a touch up by hand IMG_3418.jpg
 
Did my first ever experiment papering basswood with white glue and copy paper (normally I use adhesive label paper). Worked well; not as quick as label paper but still pretty easy. Result is impressively strong.
IMG_9721.jpg
One difference: I can actually see how the paper settled into the grain a bit. Definitely requires a coat of filler-primer on top. The label paper is heavier and stays flat (cardstock would presumably do the same).
 
I'm recuperating from a cold and wondering about why Quest got out of the BP business? Is there a past thread about that?
 

Similar threads

NTP2
What do you do (or did) for a living?
6 7 8
Replies
239
Views
7K
John Kemker
John Kemker
KenECoyote
Is it really a model rocket if you don't launch it?
4 5 6
Replies
158
Views
5K
bjphoenix
B
T
First-time UK Rocketeer looking for help!
Replies
5
Views
253
LD124
L
ljwilley
What do you think of my V2 rocket?
Replies
18
Views
2K
JPalmer621
J
M
Free Almost Free Model Rocket Building Service
Replies
1
Views
970
mh9162013
M

Latest posts

Back
Top