The MIAHINATOR

[Wrightme43]

Miah is starting on her Aerotech Initator. Sticker Shock is sending custom MIAHINATOR vinyl in black and red.

Her favorite colors are Red, Black, and Blue. I expect to paint it blue, but she may choose something completely different.

It is her 10th Birthday present. She wanted a big rocket. We gave it to her a few days early so it could ready for the launch two days before her birthday.

She is filling the spirals with water thinned timbermate woodfiller. She sanded the nose cone before I got my camera.

 

[Hobie1dog]

she's using an "acid brush"? Well that's what I call them.

 

[Wrightme43]

Yeah, the kids had taken the good little brushes and left them to dry with paint on em.
I keep lots of those acid brushes from harbor frieght for wood glue.

They work great.


It worked well on the timbermate too.

 

[Hobie1dog]

Yeah, the kids had taken the good little brushes and left them to dry with paint on em.
I keep lots of those acid brushes from harbor frieght for wood glue.

They work great.


It worked well on the timbermate too.

WOW, you're quite the woodworker

 

[Wrightme43]

WOW, you're quite the woodworker

Well thank you, Sir.

 

[SolarYellow]

The brushes I have from Hazard Frought that look like that are not actually acid brushes. Whatever the bristles are made from (maybe horse hair?) deteriorates rapidly in a strong acid.

 

[Wrightme43]

Well that makes sense, harbor frieght is not good quality. I just use them for glue, and filler so they are fune for me. I just toss em after use.

 

[Wrightme43]

Alright the Aerotech Initiator rocksim file from Apogee is all sorts of wrong.
The mass of the rocket without a motor is actually the mass of the rocket with a 29/40-120 loaded with a G53-7 exactly correct to the gram.
The center of gravity is completely off, when you add a motor in rocksim.
I was not at all happy with how close it actually was to the center of pressure measured with a string around the loaded rocket.
I added 56 grams of BBs and 14 grams of 30 minute epoxy to the nose cone.

That moved the center of gravity forward and at the same time increased altitude by 200 feet, after adjusting every thing to reality measured on my scale, and measuring center of gravity.

I read somewhere on here that the Initiator needs nose weight. I dont know who said it, but THANK YOU!!

I would of checked it, but I never imagined the file would be that far off.

Here are both files for comparison. PLEASE DO NOT JUST TRUST MY UPDATED FILE!! I added 2.5 ounces of mass in the nose cone!!!!!

 

[Wrightme43]

I did use six10 epxoy inside the fin can, but everywhere else is Starbond Medium Thick rubber toughened Black super glue.

 

[gldknght]

Alright the Aerotech Initiator rocksim file from Apogee is all sorts of wrong.
The mass of the rocket without a motor is actually the mass of the rocket with a 29/40-120 loaded with a G53-7 exactly correct to the gram.
The center of gravity is completely off, when you add a motor in rocksim.
I was not at all happy with how close it actually was to the center of pressure measured with a string around the loaded rocket.
I added 56 grams of BBs and 14 grams of 30 minute epoxy to the nose cone.

That moved the center of gravity forward and at the same time increased altitude by 200 feet, after adjusting every thing to reality measured on my scale, and measuring center of gravity.

I read somewhere on here that the Initiator needs nose weight. I dont know who said it, but THANK YOU!!

I would of checked it, but I never imagined the file would be that far off.

Here are both files for comparison. PLEASE DO NOT JUST TRUST MY UPDATED FILE!! I added 2.5 ounces of mass in the nose cone!!!!!

I used epoxy to attach the fins on my Initiator, and have been flying it for years with no nose weight. At All. I use the 29/40-120 reload case with a variety of loads including the G64, which is a few grams heavier than the G53. No stability issues at all.

 

[Wrightme43]

I used epoxy to attach the fins on my Initiator, and have been flying it for years with no nose weight. At All. I use the 29/40-120 reload case with a variety of loads including the G64, which is a few grams heavier than the G53. No stability issues at all.

Thank you, it is always a strong possibility that I am horribly mistaken, or misunderstanding something.

I just know the initator file from apogee did not match what the digital scale said.

That the unloaded wieght in the file matched the loaded wieght exactly.
When I measured CG with a string it was less than 1 caliber forward of the calculated CP.

I edited it untill the weight matched what I observed.

I am human, and totally and completely apt to screw up at any moment.

According to openrocket, it will fly higher now.

Experience in reality is much more important, I expect it would of been just fine, since these things are everywhere and considered a great rocket.

Maybe someone saved over the rocksim file after editing?

Maybe I completely misunderstand something.

Almost every file I have found has something that isn't quite right on it though.

I was very careful to measure and record all wieghts on the Journey 75, they are accurate.
The nose cone is 15" exposed, not 11" exposed.

When measuring back from the tip for center of pressure it was way forward untill the nose cone length was fixed.

The Wolverine 2.6 had the weight of a standard Wolverine, all the shapes were right, lengths, but mass was off, when fixed, it seemed happier with some nose weight, to me.

I am sure there is nothing wrong with the initator as built, just that the rocksim file from apogee does not match what my scale says.

Thank you for taking the time to tell me your experience. I hope this one flies as well as yours.


Steve

 

[Wrightme43]

MIAHINATOR decals from Stickershock!

Very cool.


Sorry for the lack of build photos. It has been crazy around here.

It will hopefully fly this Saturday in Hopkinsville Ky at MC2.

 

[neil_w]

Awesome.

Good luck with the flight!

 

[Initiator001]

Have a good flight!

 

[kjhambrick]

Awesome, Steve !

Please post a video of the flight !

-- kjh

 

[Wrightme43]

I will if my lovely wife is able to get one.

Miah did all the sanding, filling, and fitting. I did the gluing (epoxy and super glue) and painting.