Blast for nose cone

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rvanstone

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Folks,
Need a little help or advise. My new project has me drilling a hole in the nose cone (from ther bottom) for the purpose of adding blast . I was thinking of using sand for blast or lead fishing weights ? How would I make this configuration adjustable that is add or remove weight accordingly.

And Ideas ????


Ron
 

sandman

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One meathod is to open the bottom of the cone big enough to reach inside.

Epoxy a length of threaded rod. (Lowe's, Home Depot...local hardware).

Add washers to add weight and secure with one nut.

sandman
 

Elapid

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a small pill container into the base of the nose cone to give you a sealed compartment into which you could add or subtract ballast.
 

BHP

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Try the method described here: https://www.geocities.com/rdh82000/Tips/Enosecone.htm

Or, use the threaded rod idea. I put a fender washer at the fore end of the rod to increase the area of epoxy contact but it probably doesn't really make any difference. The washer does help keep the rod plumb, however.

I've added weight and eye-bolts to many nose cones using similar methods to both of these. Just cut the aft end of the NC off and make sure you rough up the interior area where the epoxy is to bond. You need to give it a good 'tooth' for the epoxy to flow into and hold on. I use a 60 grit drum on my dremel tool to do it.

I've not had a problem with the heavier gauge plastic NCs from PML and LOC but I've heard that the thinner Estes NCs can deform from the heat created from the curing epoxy. To prevent that stick the NC in a water bath ( a peanut butter jar worked well on my V2 NC) to keep it cool.

Good luck!

Perhaps the following is a breach of TRF etiquette, I'm not sure and apologize if it is, but I believe the word your looking for in this thread is 'ballast', not 'blast.'
 

KermieD

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What kind of a difference are you looking at? Couple of ounces...couple of lbs?
 

Johnnie

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On a grander scale, I added a 3/8" all thread w/ nut and washer to my nosecone inserted to within 1 inch from the tip, then I filled the nosecone with rubber silicon till it weighed exactly 5 pounds. The other end of the all-thread has a screw-on closed eye loop for recovery.

The nosecone is 5.5" dia. and sits atop a Blackhawk R&D AGM-78 Standard ARM. The silicon ballast was added for (2) reasons:

1) I did not want to make a 5 pound bullet by adding lead shot or BB's;

2) I needed the extra cone weight as the Standard ARM has strakes, which will bring the CP forward, and an M motor will bring the CG backwards...this would be a bad thing without the added weight to bring the CG forward again.

Plus I have a big ole Superball in the shape of a nosecone now!
 

scm86

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probably not a bad idea to keep it in a water bath, but as long as you have something like lead to absorb the heat, it shouldnt get too hot, i added 3 pounds of epoxy and lead shot to my estes V2 cone, no deformation, just a lethally hard and pointy cone...

on a cone like LOC IV usesm a bolt can be screwed into the hole in the base of the cone, and washers added, subtracted or the whole thing totally removed.

Scott McNeely

Originally posted by BHP
I've not had a problem with the heavier gauge plastic NCs from PML and LOC but I've heard that the thinner Estes NCs can deform from the heat created from the curing epoxy. To prevent that stick the NC in a water bath ( a peanut butter jar worked well on my V2 NC) to keep it cool.
 

BHP

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Johnnierkt - I'm curious - what is the difference between 5 lbs of BBs and 5 lbs. of of rubber in a falling object?

And Scott - 3 lbs. of noseweight? What motor are you planning to put in it? Mine, with 1.65 lbs. of noseweight, seems really heavy.

BH Pete
 

Johnnie

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BHP-

I don't know, I'm kinda uncomfortable at the thought of a 5 pound ball of lead coming down...I guess it is that whole rubber / lead bullet thing....bounce 20 ft. back into air, or impact 3 ft. into Earthly core sample regions.

If I thought I could fit 5 pounds of feathers into that cone I think I would try it :)
 

bobkrech

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You might want to consider canting the fins 1 or 2 degrees to impart spin to the rocket. This moves the CP aft and reduces the weight of ballast required for stable flight.

Bob Krech
 

scm86

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Ive flown it on a CTI 2g smokey, and a 3g standard...

Scott McNeely

Originally posted by BHP
And Scott - 3 lbs. of noseweight? What motor are you planning to put in it? Mine, with 1.65 lbs. of noseweight, seems really heavy.
 

BHP

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Ive flown it on a CTI 2g smokey, and a 3g standard...
Cool! I love those smokey motors. These are, I presume, the 38mm CTI's?

What total weight is your V2? And what altitude did you get out of those motors?

I'm throwing paint on my V2 today. I've decided to name it Bob. Another flier I know keeps telling me it's gonna shred on a baby K motor. I say no way as I "Bob Segered" this build - i.e. it's 'Like a Rock.' I was then thinking of painting it silver as a tribute to the Silver Bullet Band but decided I'm not a good enough painter to make a chrome-like rocket. Naming it Bob will have to do.

For those of you too young to know who Bob Seger and the Silver Bullet Band are: https://bobseger.com/

BHP
 

scm86

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It weighs 5 pounds dry, and it got 2060ft on the I205, cant remember what it got on the first flight...

and apologies to rvanstone for hijacking your thread...

Scott McNeely
 

rvanstone

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Guys,

How funny I grow up int Detriot and my favorite Rocker was BoB Seger.
My projet is Skunkworks 5.5 Phoenix (or now known as PoleCat Rockets) . So the instrcuctions have you placing the U bolt up into the nosecone and drilling a hole for balast . I still no sure what to do . The hole is only 1/2 3/8 in diameter.
I at the stage of priming and sanding so maybe tomm I will post some pics

Ron
 

BHP

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Thanks for the info, Scott. Sounds like a good flyer.

And since I've been intrumental in hijiacking this thread I'll go back to Gerbs original V2/38mm thread and post some pix of my nearly completed V2.

BHPete
 

gerbs4me

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It ok Pete, you can post about your 54mm V2 also

I don't think its gonna shred, if you built it strong it will hold up. Bob Seger rocks! :)
 
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