My L2 Project

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OverTheTop

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There is a minimum distance behind the nosecone for a static vent. Not sure what it is without looking it up. I'll leave that to you. The nosecone creates a wake vacuum immediately behind it.
from Verns page "They should also be well away from the nosecone joint or any other transitions in the body diameter since these can cause turbulence and either increased or decreased pressure regions.
It depends on the electronics as to how it handles the turbulence too. Personally I run a TeleMega in the NC and the vents are about 0.3 calibers below the NC curve. No problems with that setup for me.
 

bobbyg23

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I have 1 of my altimeters in my nose cone so the vent hols are on the curve and it works just fine.
 

thzero

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There is a minimum distance behind the nosecone for a static vent. Not sure what it is without looking it up. I'll leave that to you. The nosecone creates a wake vacuum immediately behind it.
Norm

Yes, fully aware. This is head in dual deployment; the nose cone has a good 4" where its pretty much straight up and down with very little if any curve in it. Basically where the smudge mark line that can be seen in the picture; that was basically from being inverted in a body tube.

Do need to do some more smoothly and joint work.
 

thzero

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I'll have to remember to take a photo or two tomorrow, but I've had good luck with the fins and vacuum bagging with just a standard food saver. First couple of attempts have had excess epoxy, however I've found that bleeder cloth as well as release cloth seem to work wonders and I have little if any extra epoxy getting on the backside of the fins.

I also plan on putting a layer of fiberglass over the leading and trailing edges. I was trying to figure out how to get the fiberglass to fold and lay down without a struggle, same with release cloth. Then it dawned on me... heat! Why not just use an older iron and not on too high of heat setting (using polyester setting) iron a crease into the fiberglass cloth and release cloth. Sure enough, it works... got a nice crease, so now the cloths can just drape over the leading/trailing edge and get vacuum bagged!
 

thzero

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Ok, so the fins are done! There is minor amount of cosmetic work to finalize, but overall the mechanical parts are done. Amazingly, I think that makes the rocket mechanically feature complete!!

PXL_20220224_144959463.jpg

PXL_20220224_145008984.jpg

PXL_20220224_145021596.jpg

Now just need some better weather so can do some ejection charge testing!
 

thzero

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Not much right now. Got some primer on the tube and nose cone. Then some more filler. Waiting for weather to get a tad nicer to go sand again and re-primer.
Need to do some filler on the fins a bit and then same.
 
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