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rockhead

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....How do you know how high up the launch rod to set the stop for the lug on the rocket? I've done a Estes Gnome and using 1/4A3-3T engine. Is there a chart by engine size or what? TIA
 

jflis

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rockhead,

I just want to be sure I understand your question...

Are you asking how high up the rod you want your rocket suspended (as opposed to just sitting on the blast deflector)?

jim
 

rockhead

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Originally posted by jflis
rockhead,

I just want to be sure I understand your question...

Are you asking how high up the rod you want your rocket suspended (as opposed to just sitting on the blast deflector)?

jim
Yup, that's it.
 

Steward

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Something my Dad always use to say...

"You'll never know the answer if you don't ask the question"...

Nothing dumb about that...in fact just the opposite...

Good luck and have fun....


P.S. 5 or 6 inches....
 

eugenefl

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Heck, sometimes a spent engine casing makes a good blast deflector. For a rocket that small, all you need to be concerned about is the clips not touching the metal blast deflector. Don't have a spent casing? A piece of masking tape wrapped around the rod about an inch off of the deflector will work as well.
 

spacecowboy

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Try Clothespins.
They burn up after about 25-30 launches, but they are totally groovy in terms of moving launch height up or down on the launch rod, or rotating the roc after it is set to go, so you can attach the battery leads to the igniter, oh forgot, or a better angle for the photo opp. The clothespin also takes the tension off the battery leads, especially from pulling the igniters out.

One caution though, on a windy day, it make shake loose and the engine hook can snag the pin, and you end up with a nice scare and ejection 15ft away. This only happened to me once, I like my skin the way it is, and it actually didn't even hurt the roc.
 

Vance in AK

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Maybe I'm missing something & messing up, but I let everything from Mosquitos & Gnomes to Big Berthas set right on the Estes blast deflector & have never had a problem. Of course I guess the Estes deflector has the 2" tall plastic center in it.

Vance in AK.
 
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I agree with steward thou his red messages make it hard to read.
the only dumb question is the one you don't ask:D We're all friends here, actually the reason I like this forum better than any other on the web is we try to make a conscious effort to keep our answers helpful and friendly.

My usual rule of thumb is the length of a motor casing. 1" to
3" for MMX thur D12 motors. Cloths pins are great stops or slide a spent motor casing over the rod down to the blast deflector, allowing the bottom of the model body tube to rest on the casing or cloths pin.
 
A

Austin

Micro makes a good point...our club slides old used motor casings over our 1/8" - 1/4" rods for spacers. They are free and work well. For those tailcone rockets, you can use a "D" casing, which reaches deeper and for the bigger rockets, empty 29mm Single Use casings work great. Also, if more space is needed, the casings can be stacked, thus doubling your distance from the deflector.

We have also used the clothes pin, although it has a tendancy to slide down on heavier models.

Carl
 

dtomko

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The spent motor casing has worked well for me. Some rockets don't need anything, but you can scorch the bottoms of fins with the Estes deflectors.
By the way, I really preferred the Centuri angled deflectors over Estes round ones. Does anyone make deflectors like those (hint to Semroc!)? Of course I could just use a split open coffee can.
Drew Tomko
 

powderburner

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Originally posted by Vance in AK
I let everything from Mosquitos & Gnomes to Big Berthas set right on the Estes blast deflector & have never had a problem.

I do the same thing, especially if the rocket has swept-back fins (it can just stand with its fins perched on top of the blast plate). Just so the igniter leads don't lay on the metal blast plate and short circuit.
 
A

Austin

Tomko,

You can make your own angled deflector pretty cheap. I go to the hobby shop and they have K&S metal sheets that are 6" x 9" or so...You can bend them and they make great deflectors. Mine has lasted many years, and flights, without corrosion.


Here are a couple pics:

<a href="https://www.rocketryforum.com/amraam/paddeflector.jpg">Pad Deflector</a>

<a href="https://www.rocketryforum.com/amraam/launchpad.jpg">Launch Pad with Deflector</a>

Hope this helps,

Carl
 

dtomko

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Thanks, Carl. That looks great!
Drew Tomko
 

astronboy

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In the old days, I used to just set the rocket on the deflector plate, but that resulted in a few scorched fins, and ruined paintjobs. :eek:

These days I usually use a clothespin, but I also carry a small assmble of scrap wood blocks in my range box. All are between 1 and 2" in any dimension, and they come in handy sometimes. ;)

Carl, Is that KS steel stock you use for your plate?
:confused:
 

jflis

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Originally posted by dtomko
The spent motor casing has worked well for me. Some rockets don't need anything, but you can scorch the bottoms of fins with the Estes deflectors.
By the way, I really preferred the Centuri angled deflectors over Estes round ones. Does anyone make deflectors like those (hint to Semroc!)? Of course I could just use a split open coffee can.
Drew Tomko
**hey**! "hint to Semroc" indeed! :) (just joshin')

Seriously though, FlisKits is hoping to come out with a pad by mid-late spring (if we're lucky... *S*) and an angled blast deflector is one of the key ingredients that we're hoping to offer.

For me (to address the question), a spent motor casing is my choice. It's free and you *always* have one (well, at the very least, after your first launch)...
 

dtomko

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Ooops!!! No slight intended, Jim. I didn't know FlisKits was going to come out with a launch pad. Cool, I can't wait to see it.
Drew Tomko
 

jflis

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oh, i was just pullin' yer chain *S*

we haven't talked much about our support equipment plans as they are still very general but we're working on it.

And i'm sure SemRoc will come out with a fine launch pad. They seem to be off to a very good start!
 
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