Semroc Hydra VII

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Well-Known Member
Jul 1, 2012
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Need a little help please.
Instructions say to attach the inner fins flush with the bottom of the motor tubes. The trailing edge is angled so the engine tubes will extend below the augmenter shroud if the augmenter shroud is attached flush with the trailing edge of the inner fins. Is this correct? I'm looking for help instead of following my usual male tendency to jump right in and then have my kids presented with a lesson in unacceptable terms of endearment.

Thanks in advance,

Correct, the large ring is about 1/4" above the end of the motor tubes. The only thing I did different is not use the 18mm caps on the thrust rings. The idea was to loose the expended motor cases and use only the center motor for ejection. Suppose all motors light except the center? I use 13mm tubes with the 18mm caps glued on top and a 1/4" slice of an 18mm motor case as a centering ring at the bottom in unused motor tubes. Friction fit. I keep 6 of these in my range box. I lose a few once in a while.

And you sound familiar!

Thanks for the input. I like your idea for unused tubes.

Familiar? Could be. Let's see, do you by any chance have a white van and launch somewhere in, uhhh, well darn, there goes my crystal ball. Wait a minute while I put in a new fuse.

OK, I'm back. Everything is clearer now. I see a great green expanse that resembles a sod farm somewhere in Alabama and there's a catalog store there that... no, wait, its the Southeast Alabama Rocketry Society!! SEARS 572! Serious rocket guys they are.

Yep, its me.

sniff, sniff.....smells like a hydra 7 drag race comming. <grinning> Get plenty of C's and work up from 1 C6-3 to 7 C6-7's. Awsome flights. I'll make more igniter extensions. Hope I don't have to work again.

Janruary 8th, ya'll. Samson, Ala.

The young son has Cub Scout Pinewood Derby workshop January 8th. Scouts will come first for him so I'll have to beg off on the drags until February. He crosses over to Boy Scouts in February but I think the launch date is before the banquet. Between TARC students and Boy Scouts we could have a huge herd of 'fetchers'.