Fliskits EMK3-24-70 question

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Well-Known Member
TRF Supporter
Feb 19, 2009
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I'm starting to gather parts for my Red Max upscale and I have a question. (Jim...if you're back). The rocket will have interchangeable motor mounts. One I'd like to use is the 3-24mm cluster in a BT70 tube. Fliskits has two options on this mount. I'd rather use the classic engine clips to hold in the motors so I'm interested in his EMK3-24-70 kit. The other style mount doesn't have the clips, and I'm not a fan of masking tape to hold engines in....too much hassle.

The question. In this mount the three 24 mm tubes mount inside a BT69 tube without any centering rings...then this all fits inside the BT70 tube that's the rocket's body. BUT...without any centering rings, the back end of the rocket is open between the 24mm tubes. Wouldn't this vent some of the ejection charge? Or is the ejection charge from 3 24mm's enough to still pop the nose cone? I suspect that it is...just wanted to see if anyone's used this cluster mount in a rocket yet.

yeah what doug said.....this prevents the gasses form escaping
You could also use gussets ala FlisKits' Caution Rocket. Not as easy, but nicer looking.
yep, i'm back... not bad enough that I have to dig through a mountain of email and a mountain of new TRF threads, but now a mountain of snow too! LOL (well, actually, it isn't really bad here in New Hampshire. we only got about 4 inches around my place)

gotta love New England in the spring... :p

What the others said about the tissue filling the voids. It is detailed in the instructions and is a tried and true method of filling the voids. As for engine hooks in the other engine mount kit (EMK3-24-70R), you could order a pack of hooks and make a slight modification to one ring (to clear the hooks) and it would work fine. We didn't include hooks in that kit for 3 reasons:

1) cost (aside from filing voids, if you want hooks you can purchase the 24-70, if you don't want the expense of hooks, you have the 24-70R)

2) Choice (some like hooks, some detest them)

3) Engineering. We had several folks comment that they hate filling voids with tissue and would much prefer a ringed solution. When we got the sample rings in I decided that the outter wall of the rings is *so* thin that adding additional cuts for the engine hooks would just weaken them further. This isn't a problem once assembled but *is* a problem with packaging and shipping.

hope this helps!