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Newbomb Turk 09-20-2014 09:08 AM

Questions - I got'em!
 
1) Have I boofed my A-20 Demon clone? In my desire to have room in the body tube for the chute and plenty of shock cord, I wanted to push my Semroc baffle well into the tube. Now I'm thinking it might be too close to the engine mount. Does it damage the baffle or prevent it from functioning properly if it's too close to the engine mount?
2) Midway through a Maxi-Icarus clone build. Is there a common current rocket with a five inch BT-60 PST, like the Loadstar I or II? Or should I just bite the bullet and pay for 600 PSTs in the Estes payload pack?
3) Finally, does anyone have a good scan of the fin pattern for the Sky Raider?

Thanks all!

tbzep 09-20-2014 09:14 AM

A baffle will burn out a little quicker down close to the motor. If you plan on it being your "go to" bird that flies each and every time you go to the field and you fly often, it will eventually burn it out. If you only fly it a few times a year, you will lose it to a tree or a cato long before you burn it out. :cool:

I used fluorescent light bulb safety tubes for my payload section on the Maxi-Icarus.
The number on my tube is 404329, made by Lithonia.
http://www.homedepot.com/p/Lithonia...4-R24/100173390

Newbomb Turk 09-20-2014 09:16 AM

Thanks, Zep! Fast and quality answer. I will moderate the number of flights to lengthen the life span.

tbzep 09-20-2014 09:23 AM

Quote:
Originally Posted by Newbomb Turk
Thanks, Zep! Fast and quality answer. I will moderate the number of flights to lengthen the life span.


I edited my post to answer your second question a little better.

Rich Holmes 09-20-2014 03:15 PM

Pushing the baffle back also affects the center of gravity in the not so good direction, of course. But probably not catastrophically, and you presumably know enough to check.

Rich Holmes 09-20-2014 03:23 PM

Loadstar II does indeed have a 5" BT-60 clear plastic payload section. The RTF Loadstar does not (payload section isn't clear). Then again, Estes sells the Loadstar II for $21 versus $18 for the clear payload section assortment.

tbzep 09-20-2014 09:16 PM

Quote:
Originally Posted by Rich Holmes
Loadstar II does indeed have a 5" BT-60 clear plastic payload section. The RTF Loadstar does not (payload section isn't clear). Then again, Estes sells the Loadstar II for $21 versus $18 for the clear payload section assortment.

The 4 ft long clear tube that I noted in post #2 is $3.47.


.

jbuscaglia 09-20-2014 09:36 PM

I'll second the fluorescent light tube. I use some to convert a damaged Semroc Goliath into a night flier. The Goliath uses ST-16 tube, which is a couple of thousandths of an inch larger than a BT-60, and it only took a bit of masking tape to make a snug friction fit.

astronwolf 09-21-2014 08:45 AM

Quote:
Originally Posted by Newbomb Turk
3) Finally, does anyone have a good scan of the fin pattern for the Sky Raider?

There are the JimZ archive plans: http://www.spacemodeling.org/jimz/est1290.htm

If you don't like those, I might be able to come up with something better. But IMHO, the patterns on JimZ are good to go.

Newbomb Turk 09-21-2014 05:51 PM

Thanks, all! And Wolf, that scans works perfectly. Now.
I had to uncheck "Fit picture to screen" to get the proper scale, but now I'm very happy.

As to the center of gravity, the baffle is BT-55, and the Demon is fairly nose-heavy anyway so I agree that any problems should not be catastrophic.


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