BBaby Bertha

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Screaminhelo

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O.K. the name is a bit of a misnomer, I lost the original NC and replaced it with a PNC-60 from an old Patriot kit (I like the look, a bit like a Falcon missile).

Anyway, this started out to be a Baby Bertha with a boattail (fashioned from a BNC-60Y).

I am not a terribly clean builder and there is some extra weight in this thing, dry weight is 105g and pad weight ranges from 140-150g depending on motor configuration. Max pad weight for the Estes C6-0 is published at 113g, so I whipped up an OR design to help in playing with weight reduction. According to OR, speed off of a 6ft rod is marginal for all but Quest booster motors, so I have started sanding down the finish to re-paint since the finish on this thing is pretty thick. My guess is that the refinish will only reduce weight by a couple of grams. I have a couple of ideas for further weight reduction but I figure you guys will have ideas that I haven't considered.

Here it is before sanding

BBabyB_Clean.jpg
 
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Tinker

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Edit: I think my reply was in error. Is this a two stage? I thought you may have been looking at the booster engine to save weight, but once I actually looked at the picture, it would appear my composite motor idea was folly. To answer your question, would an adhesive 'clump' be lighter than the back of the nosecone? If so then may carve the back out back of the NC and adhere the shock cord to the wall of the NC? Drill a few holes in the rear centering rings?

Tinker
 

Rex R

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I managed to knock 12g off my bbertha by swapping out the 'heavy' nylon chute for a diy trashbag chute.
Rex
 

Screaminhelo

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I do have extra shoulder that can go away, I should be able to trim it down to about 1/2 inch. I hadn't thought of the trash bag chute. Both of these will save much more weight than refinishing alone and I think that this one is going to need all of the help it can get.
 

Rex R

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two things to consider, the cheap trashbags (and some store bags) are thinner, also can be decorated with marking pens.
Rex
 

Screaminhelo

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I like it. I think you did a great job and the paint is outstanding!!
Thanks but much of the shine is from chasing self induced paint problems, thus extra weight. The re-spray will probably not shine so much but it should look good on the pad.
 
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