idly thinking of thrust plates

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watermelonman

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I got some advice, from an N5800 veteran, that metal thrust plates are simply not needed for well built fiberglass rockets when using techniques such as injected fillets. I have no reason to doubt this.

However, I like the look, and it seems a convenient way to get the flanged retainer on there without a bunch of precise drilling and backing nuts.

Thoughts from those who have done this, before I start my first serious high power build?
 
Never bothered with inserts or "backing" nuts. Just drill holes in CR and self tap the supplied screws into place.
Install like changing a tire.....drill hole..install screw...go to opposite side, an so on. Don't fully tighten till all are in place...just like lug nuts on tire.

Lost them once and installed flanged AP with plain old sheet rock screws...yup that's the one I flew N-5800 in.

Ultimate Wildman...with 1010 buttons. 12 of us drag racing N-5800's all at once, quite the sight.

Don't overthink this stuff. Ya want to build a rocket.... or assemble it? LOl
 
You don't *need* the fancy aluminum thrust plates. That being said, I use them because I like the look. They add weight to the wrong end of the rocket, so the design needs to take that into consideration. They are a luxury item - not a necessity.

Here is an example, 6" rocket with 75mm motor mount.
IMG_0713_20_zpsne2xqztz.jpg
 
I have one on a Madcow 4" fiberglass Little John I recently finished. Likewise, I just like the looks of it. Yes. It is beyond overkill and required some extra weight in the nose. Although this is for my L1 attempt, I do anticipate flying it on larger motors if I ever get my L2. But it's still not really needed.


IMG_3117.jpg


Dennis
 
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You don't *need* the fancy aluminum thrust plates. That being said, I use them because I like the look. They add weight to the wrong end of the rocket, so the design needs to take that into consideration. They are a luxury item - not a necessity.

Here is an example, 6" rocket with 75mm motor mount.
IMG_0713_20_zpsne2xqztz.jpg

That does look cool...and color coordinated too!
 
Just purchased my first thrust plate from SC precision. Nice product. This is going on Gary T.'s 5" Shape Shifter and I like the idea of the motor pushing on everything at once. My planned installation will distribute the thrust equally to the motor mount and the airframe rather than trying to push the motor mount up through the airframe and will not be as stressful on the CR to airframe glue joints.
I have no reason to think the glue joints wouldn't hold but I like this idea better since I am planning on some major 4" impulse in this rocket. Also, it looks awesome.
 
Here is one on my Shape Shifter 5. Necessary...no. Nice to have...very much. Though no big deal to do yourself, it was nice to have 12 perfectly aligned and nicely tapped holes that match the retainer.

016.jpg

11.jpg
 
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That's a serious chunk of aluminum. I hope that was lightened up after that picture was taken. :y:

It was lightened up before that picture was taken. Like I said, it's a lousy pic. And for some reason, this thing won't let me post another. :mad:

It started out as a solid puck, but has been hollowed out. The thickest piece in that pic is the rear closure of the Rouse-Tech casing inside it. Ask Dave to bring his "new" ARLISS-M booster section to lunch. Came out pretty darn nice, even if I do say so myself. :D

But Dave said so, too, so we're both happy. :smile:

Maybe this will work...

View attachment 267612

Note the lip inside, to catch the mmt tube. That's only about 1/16" thick. The thrust plate portion, where the holes are being tapped, is 1/8" thick. So are the sides. They get drilled and tapped for installation in the a/f tube. ARLISS-M birds are assembled with screws. No epoxy.
 
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What can I say? Lousy pictures, taken with a crummy camera, by an even worse photographer... Me. :facepalm:

Ask Dave about his new Arliss booster. It did come out pretty sweet. He'll get another 50+ flights out of it. :wink:
 
Ah Ha! It looked like a solid 3/4" chunk of aluminum in the first pic.

Probably actually was a 3/4" (or more) thick piece. Doing it in a lathe and without some special fixturing (which would not make sense for a one-off), you need that much to chuck on the material, and leave some hanging out to work on and section off. I think I'm going to mount a helmet cam to my machine and show a fast motion of one being produced just for fun. I do them a little different in order to be efficient in production, but I always think its cool seeing how things are done. Nice job!
 
I like them too, but I don't think they need to be so thick (and that's not a great part of the rocket to add a lot of weight).

I used a 1/16" 6061 thrust plate on my Iris:

sustaineraftend1.png
 
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