Four fins and a Bowling Ball?

This is a quick thread to show how I built a simple bowling ball lofter for LDRS.

Fin can.

29mm for that kick butt H268R.

Fin slots in 4" LOC tubing. I scored them with a hobby knife, then cut them through with hobby hand saw.

The bowling ball with the necessary hardware. How did I get a hole drilled all the way through an 8.5" ball? Well I'll give credit to my dad there. He welded a 5/16" bit onto a piece of all thread and we used his drill press. I think we were both kind of impressed with result. He chuckled and said "never thought I'd be drilling a hole through a bowling ball!". But it worked.

The rules require a closed eye.

What do YOU think this resembles?

This is kind of blurry cause no tripod in low light equals well, blurry.

Looks nice..Guess it would qualify for the 'Large Dangerous Rocket'

But the real question is: 16lb or 15lb ball? Straight poly or reactive poly?

Wow! Fascinating and innovative are the first words that come to mind. Is it going to be stable? Also, why didn't you put a 38mm MMT in it?

Loading and prepping. Notice the large 6 grain case. Also the small asian condom holding the ejection charge. That realy is just a finger condom and it did not work.. LOL I had to resort to tape. Oh, thats my nerdy butt on the left.

There goes the igniter.

And....


Money shot!

But the real question is: 16lb or 15lb ball? Straight poly or reactive poly?

Click to expand...

Its an 8lb ball. It is not reactive no. I'm a bowler too.

Wow! Fascinating and innovative are the first words that come to mind. Is it going to be stable? Also, why didn't you put a 38mm MMT in it?

Click to expand...

Thanks, as you might imagine with all that nose weight you actually have to fight against having an overstable design. I picked a 29mm mount because of the parts I had on hand really.
The rules only allow for a small list of given motors so I went with what I had.

Nice job!
That H268 has a huge flame, wow!
I've flown a few I200's, but I may have to try that motor.

Very nice, though honestly I would have gone with the 38mm H999 instead to get the extra punch off the pad.

The 268 is a fun motor though, no question, and it looks like it worked out great

Thanks guys, that H268R motor is nice. I know that most people will use the H999 and so be it. Simple and easy was the word of the day for me. I can fly my rocket dumb.

gonogo said:

And....
Money shot!

Click to expand...

Wow. That is amazing! I can't believe you actually launched a bowling ball. That was definitely one of the most interesting ideas I've ever heard of. Very cool!

Looks like it was a nice launch! Do you have an idea of how high it went?

It was probably 10+lbs at launch, and it was an H motor...

I can't imagine more than 500 feet...

cjl, I think you peeked at my rocksim file, your guess is too good.

Its not just an H motor, in fact any more impulse and it would be an I200, same casing just differant fuel. It is a full H, about 95%.

I am just as impressed as most of you all are. I have been wanting to launch a bowling ball for as long as I have been into high power, and am stoked to have done it. This is however a duration contest and therein lies the challenge.

Nope - I don't have rocksim on this computer, and my sister's been hogging the one that does have it all day...

It is definitely a large H motor (I've flown a couple, and love them), but it is an H nonetheless. I've flown rockets that were 12lbs on an I600, and they didn't go that high, so 10lbs on an H would really be a low flight, hence my 500 foot guess.