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Karl

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Im looking for different types of nose weight to add on my Bigger Daddy. I've added bb's , epoxy ect .
And could someone please tell me , because Im lacking quickmatch at the moment. I want to fly my Bigger Daddy on 4 x D12-5's. And my launch controller is capable of launching 2 pads, so if I twist 2 Ignitors together then the other 2 together , and connect the crocodile clips the the posotive & negatives using one pad cable, then the same with the other cable . Will 12v 7.2mAh have enough 'umph' to fire al 4? As my controller can fire 2 pads simultaneously.
Karl
 

mkmilion

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Have you tried using modeling clay? I got approximately 1 lb. from the dollar store. I works fine. I haven't used it for sometime as big as a Big Daddy, but it should serve it well.
 

Karl

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Cool thanks for that I'll try it tomorow If I can find any. Will Millput work?
Karl
 

lalligood

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I'm a big fan of lead fishing sinkers held in place with polyurethane glue (like Gorilla Glue). Poly glue expands (although not nearly as much as 2-part foam & doesn't require any mixing) & sticks to darn near anything! It just needs a warm, humid place to cure for a few hours...
 

hokkyokusei

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Originally posted by Karl
And my launch controller is capable of launching 2 pads, so if I twist 2 Ignitors together then the other 2 together , and connect the crocodile clips the the posotive & negatives using one pad cable, then the same with the other cable . Will 12v 7.2mAh have enough 'umph' to fire al 4? As my controller can fire 2 pads simultaneously.
Karl
Yes. Done this several times. If you have two pairs of clips, you can save some twisting by wiring the four igniters in to a bridge. The bridge forms a square, connect positive and negative clipe to opposite corners. For added reliabilty, examine your igniters carefully. Pick ones that look "good", by which I mean well-formed and with a fat blob of pyrogen.
 

swimmer

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Karl,

I like modeling clay and have always used it until I had to put 1.5oz. in my A-Slam balsa nosecone. I drilled three 1/2" x 2.5" deep holes and weighed the modeling clay to the 1.5oz. I found there was not enough capacity in the drilled holes to install that much clay. So, I used lead fishing weights. It took nine weights of various sizes to weigh exactly 1.5 oz. Three in each hole backed with 15minute epoxy and voila, my A-Slam is stable. Clay is useful a lot of the time but too much bulk for the weight sometimes. I will still use clay in plastic nosecones.

Just my .02 worth.

Swimmer
 

Micromeister

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Karl:
Most of us have used modeling clay at one time or another covered with epoxy, CA or some other type glue. If you use this system be aware over time, flights and landings. the noseweight can sometimes release making the model go unstable.
I've switched to Lead Shot in epoxy. #9 is the smallest dia. available which packs the most weight the furthest forward. this REDUCES the amount of noseweight needed a little also. It's another McMaster-Carr purchase;) but well worth it.

On your 4 D12 cluster you really should be using a relay ignition system and Hi amp/hr battery. heres some common motor wiring hook ups i've used for a long time
Hope this helps
 

powderburner

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I do not disagree one bit with Micromister's comments, just want to point out one additional procurement option.

For a handy supply of #9 lead shot, you do not have to order from McMaster-Carr (and I have nothing against them). Just go to your local sporting goods retailer and find a box of 12gauge shotgun shells loaded with suitably-sized shot. If you can't find #9, then use #8----there is little difference. Open the shotgun shell by cutting around the front, and dump out the shot. There you go.

Dispose of the remainder of the shell in a responsible way. You can pull the shot wad out and dump the propellant into the trash. It is NOT black powder, it is nitrocellulose, and it has very very few applications to model rocketry. Before you throw away the empty shell, don't forget to safe the primer by placing a couple drops of oil (3-in-1 is very thin and works well) inside the bottom of the shell to seep through the flash hole and deactivate the primer compounds.
 

cls

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after my Saturn V crashed and spilled 24 pounds of lead shot - that was a royal pain to clean up - I thought there has to be a better way. you can't just leave the lead there, it really is poisonous.

a 25# sack of #9 lead shot was $20, or $0.80 a pound. that beats $2/pound for lead fishing weights. you can generally get small pieces of lead for free at the tire store, but collecting more than a few ounces will mean many trips all over town, probably not worth it.

Washers at the hardware store are generally about $1.50/pound. steel buckshot is generally about $1/pound. don't know about BBs but they are probably cheap too.
 

powderburner

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"steel" buckshot is regular lead shot with a steel plated cover; this will be an effective ballast material

BBs are brass, and brass is not too dense; this is not as good as a ballast material

as far as $ per pound, do you want to hear what it costs us to use depleted uranium at work? (I gotcha beat all over the place)
 

ravenx99

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Originally posted by powderburner
BBs are brass, and brass is not too dense; this is not as good as a ballast material
I'm sitting here looking at the carton of Copperhead BB's on my desk, and it says they're made of steel.

Lead has a density of about 11.4, steel runs around 7.5 to 8, brass about 8.6. So I suppose we'd be better off if the BB's were brass. But lead will be about one-third heavier than steel, so if space is at a premium, lead is the way to go. But BB's are easier to get ahold of than lead shot. (Because I just steal them from my wife's sewing box.)

(She uses BB's to fill plush bear butts with, so they'll sit up properly.)
 

Karl

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Cool that reminds me! I have some .22 BB's lying around , the copper colour ones. There in a small red round tub with a snake on the logo? They are purty heavy tbh!
 

Hospital_Rocket

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Couple of ideas

Has anyone ever considered:

Sand? Mix with epoxy.

Portland cement?

Concrete?

Plaster?

And for the weird one...

Water. You could mount a bottle in the NC and fill it as necessary. Want to keep it in place? Freeze it. Use your NCs to keep your lunch cold.:)

Just musing.

A
 

powderburner

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Originally posted by ravenx99
I'm sitting here looking at the carton of Copperhead BB's on my desk, and it says they're made of steel.
Boy, you can sure tell it's been a looong time since I went out and bought a tube of BBs. They probably are steel now, as that is easier and cheaper to make BBs from. Much harder on your barrel, though.
 

Micromeister

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It's been awhile since I bought Shotgun shells also but I think #9 was mostly in 410 gage "Bird Shot". Powder I'm not much into having folks cutting up shells but I guess they would be a little easier to get. Ya might also want to ask the shop owner if he sells or has access to reloading supplies. He might have some #8 or #9 shot there.
#9 lead shot is .080" in diameter, #8 is .090" while a 10th of an inch may not seem like much, You'll be amazed at the difference in volumn the same amount of each fill. Maybe not so important for LPR standard size models but very important for Micors:D McMaster-Carr Cat #9030K21 a 5 lb package apporx. 45,600pcs @ $15.49 my last order.. with a bunch of other tiny brass tubing and stuff cost an additional 4.60 UPS. Shipping really isnt' that bad.

Hospital_Rocketry:
Epoxy/Sand mixes are fine for larger jobs, but will require nearly 9.5 times the volumn for the same mass assuming we're using the same epoxy to hold both in place. It's a great easy access material if you have the room;)

Just for fun here are the specific gravity and mass per cubic foot for some of the materials we've been discussing
Epoxy 78.3lbs/cuft Specific Gravity 1.26
Quartz Sand 75.0lbs/cuft " " 1.20
Brass (cast) 534.0lbs/cuft " " 8.56
Bronze(cast) 509.0lbs/cuft " " 8.16
Steel (cast) 490.0lbs/cuft " " 7.85
Lead (cast) 708.0lbs/cuft " " 11.35
Drat! no listing for Feathers to compare which will hurt worst, being hit by a pound of lead or a pound of feathers:D LOL
 

Elapid

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are much cheaper to make from lead due to the lower heat requirements for melting the softer metal.

i believe the reason they use steel shot now is because of the toxic nature of lead in the environment.

i am pretty sure you don't have to take apart shotgun shells to get lead shot, just buy it in bulk from a guns & ammo shop.

it's cheaper than the equivalent weight of quarters.

:D
 

powderburner

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Yeah, I know you can buy a bag of shot, I've done it myself.

But if you only need a little bit (like a few ounces), a $3 box of 12 gauge shells is a lot cheaper than a $15-20 bag of shot.

Micromister, #9 shot is indeed available in the bigger shells, but you may have to do some digging around to find it. And yes, #9 definitely packs into less volume, but if you just can't find #9 then just about everybody sells shells loaded with #8. As far as opening shells to harvest the components, I just don't see much danger there if you use ANY common sense in handling things. But then, after re-loading a few zillion of these shells, you get kind of accustomed to working with primers, powder, and presses. (How's THAT for alliteration?)
 
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