I ordered from Buffalo the day this post came out and have had it since Friday I think. I was surprised it came so fast.
GOEX Closing
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Kind of off topic but- do you leave the red "cover" on or remove it? Now I know why one of my bulkheads seemed to have powder burns on it. Not residue, it looked like ignited spilled powder.
Red cover? So you are referring to motor ejection? I don't understand the question. If you remove the cover, then all of the powder falls out all over the place.
Sorry about that. The ematches I use have a red plastic "cover" (poor term, it's open ended) over them (I think most do but I only use one brand). I have always removed it but always only means recently, like my first dual deploy launch was last weekendRed cover? So you are referring to motor ejection? I don't understand the question. If you remove the cover, then all of the powder falls out all over the place.
NateB
Well-Known Member
The red shroud on an ematch protects the head of the match from accidental ignition from friction as well as directs the flame in the same direction. I know it is common practice to slide the shroud out if the way, but it is best to leave it in place.
heada
Well-Known Member
e-match head shroud.
Like 99% of people, I toss them when I'm using the ematch. Never thought about keeping them for someone else but I will now.
Interesting. I never would have considered that because A) I would have assumed that it would melt and stick all over my bulkhead, and B) I don't have room in my charge well for the extra bulk.
Got a picture of a loaded well with the caps on? I'm curious. Thanks.
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For the size rockets I fly I don't need huge charges and I install the ematch through a hole in the bottom of a centrifuge vial. For everything to fit and work properly, the red plastic protective shroud has to be removed from the ematch.
NateB
Well-Known Member
The shroud will singe, but won't melt all over the place.
Most charge wells won't fit the shrouded match. I don't have pictures, but I typically cut off the end of a nitrile glove and pour the measured powder into the fingertip and then tape the little ball to the shroud. I either leave it loose or place the small ball with the shrouded match into the charge well with a piece of tape over the top to hold it in place.
I leave the shroud on. I push the shroud into the BP, add dog barf and tape.
I remove the shroud. Because the match head is in direct contact with the BP I feel there’s no benefit to having it. Given a fixed volume in the centrifuge vials I use, I would rather have the little bit extra volume of BP.
beeblebrox
8 C6-0, 12 D11-9, 20 D20-0, 20 E5-0, 3 Cinerocs
For my older charge wells I removed the shroud thing, bent the wires over the edge of the charge well, put in the powder, then taped it shut.
My latest charge well , integrated into a small sled with an Eggtimer Apogee, I wanted to make sure that gases did not go rearward into the circuit area. The cap thing was the solution! I trim it a bit shorter first (Need to make the hole where it fits deeper next time) , then I put a small bead of "DumDum" (That sticky stuff we used as kids to stick stuff to the wall) around the wires. Push it down into the charge well, this seals it at the wire end perfectly. 3D printed cap snaps into charge well, no tape! No blow by in 5 flights.
My latest charge well , integrated into a small sled with an Eggtimer Apogee, I wanted to make sure that gases did not go rearward into the circuit area. The cap thing was the solution! I trim it a bit shorter first (Need to make the hole where it fits deeper next time) , then I put a small bead of "DumDum" (That sticky stuff we used as kids to stick stuff to the wall) around the wires. Push it down into the charge well, this seals it at the wire end perfectly. 3D printed cap snaps into charge well, no tape! No blow by in 5 flights.
DAllen
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Out of curiosity....for DD purposes what is the difference between 3F and 4F?
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None.
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For those of you still looking, I found a supplier that will sell and ship 1 lb of Swiss 4FG.
https://www.addictedtoblackpowder.com/
https://www.addictedtoblackpowder.com/
3F grains are slightly larger, so they need to be compressed more.
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Seems that more folks report 'scorching' or 'nomex burn through' with 3F than 4F. Likely because the larger grain size burns longer, or at least long enough to come into contact with the recovery bundle while still burning.
I think this is key. At BALLS this year I wanted to fly three fairly high performance MD rockets, a 54mm, 75mm, and a 98mm. I had all of them 'mostly' prepped, or so I thought. Each one was set up completely differently for recovery, as they were built at varying times in my 'career'. Partly because of that, it took a lot longer than it should have because there was very little consistency between the prep. In the end I only flew 2 of the rockets because I was just not happy with how the third was set up. I've decided to mostly start over with a lot of my better rockets and set them all up basically the same way.
Consistency is the friend of reliability.
Tony
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I believe that both Pyrodex and 777 have been "optimized" to use the fuels and oxidizers present in each formula efficiently. I think if you tip the scales lean or rich in regards to fuels or oxidizers you will see a reduction in performance.
I think that they were optimized for tightly-contained use, in a firearm. If they were optimized to burn most efficiently under low compression, they would be more suitable for Rocketry usage. From what I remember, the Oxidizer / Fuel ratio controls the rate of combustion, right ?
Dave F.
Let us know if that arrives. The website is sketchy.
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Will do! Talked to the guy and didn't even think of that until just now.
Got the tracking number same day as payment, so we should see in just a few days
DAllen
Well-Known Member
I messaged them and going to pay via PayPal G&S. Not real comfortable giving a cc# over the phone...We'll see what happens.
Kelly
Usually remembers to get the pointy end up
What did shipping/hazmat total to?
What all did they have and how much did you have to order?
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Shipping was $60 to California. I also paid via PayPal, but they are an authorized dealer for Schuetzen which is how I found them. I was looking for 4FG specifically so didn’t ask about much else. Ordered just a pound.
SharkWhisperer
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Jeez O Peets! That's 3x the product cost in hazmat shipping alone. Having a ball mill, that pound equivalent would have cost me about $2 in chems and my homemade willow or ERC charcoal. Perhaps an hour of hands-on time weighing, milling, mixing, granulating, screen-sizing. Decades of ejection charges. Or a slow evening lifting shells in fireworking... It's both cathartic and rewarding. And inexpensive.
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