 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
| HomeDiscussion Groups General ModelsRailroadsRocketsRadio Controlled Air ModelsHelicoptersLand ModelsWater ModelsModelGeeks.com Contact UsLink To UsSearch & Site Map |
Model Forum / General / Rockets / August 2006E-Match Question
Is my understanding correct that in order to obtain/possess e-matches (such as Davyfires, Oxrals, M-TEK's, etc.) that you must have a LEUP? If so, what are most of the non-LEUP holders using for ejection charge firing? I'm aware of flash-bulbs but would care not to go that route. Any input would be greatly appreciated. Thanks! Chuck Neff TRA #7915 L3 NAR 74595 L3 Why won't anyone respond? I realize that I'm not a regular poster, but I do frequently visit the group. There can be good info. found here at times (as long as you can read between everything else). Please? > Is my understanding correct that in order to obtain/possess e-matches > (such as Davyfires, Oxrals, M-TEK's, etc.) that you must have a LEUP? If [quoted text clipped - 5 lines] > TRA #7915 L3 > NAR 74595 L3 > Why won't anyone respond? I realize that I'm not a regular poster, but I do > frequently visit the group. There can be good info. found here at times (as [quoted text clipped - 9 lines] >> TRA #7915 L3 >> NAR 74595 L3 Didn't see your post until now, odd ;/ Well, I'm still working on my last box of Daveyfire 28B's so I'm pretty set. That being said I used to use flash bulbs but those are VERY hard to come by now-a-days. Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. $1.99 gets you a whole string of them at Target. That's about the price for one ematch, total bargain. Ted Novak TRA#5512 IEAS#75 > Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. Do you take the glass of Xmas bulbs - or how do you get enough heat? H >> Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. > > Do you take the glass of Xmas bulbs - or how do you get enough heat? > > H The way I've seen it done is to crush the tip of the bulb exposing the insides, hot glue bulb in a crdbrd tube and fill with BP. I'm sure google could come up with some sites. Ted Novak TRA#5512 IEAS#75 > > Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. > > Do you take the glass of Xmas bulbs - or how do you get enough heat? > > H http://www.perfectflite.com/Downloads/Ejection.pdf I used this method once for dual deploy and it worked 50%. I had continuity on the altimeter when the rocket launched, but during flight, the bulb in the drogue section wound up coming loose and didn't fire. The bulb with the main deployed perfectly though. I haven't taken the time to really think of other ways to make this work, but I am sure there are many ways to do so. Plus they are SUPER cheap, so if you figure out a reliable way to use them, then great! I was on vacation recently and stopped by a fireworks showroom. They had refill fuse "e-matches" for an inexpensive fireworks firing console they also sold. After seeing them, I went ahead and bought two boxes (25 e-matches ea.) for $9.95 each thinking I may be able to use them. They're basically a little plastic closepin with a filament inside notched to hold on a fuse attached to 5' leads. I did some bench testing with them on an RRC2 and every one fired. I added some black powder and tested a few more. Again, every one fired. I was very pleased with the results and the cost of about 40 cents each. The other good thing was that I can order more and have them shipped to me with no problems. Anybody else seen these? > http://www.perfectflite.com/Downloads/Ejection.pdf > [quoted text clipped - 6 lines] > work, but I am sure there are many ways to do so. Plus they are SUPER > cheap, so if you figure out a reliable way to use them, then great! Care to share your source? I need a new source as I'm down to only 4 Oraxals (SP?) left in my stock. Each flight of my 1/2 scale Patriot uses 4 matches (2 per altimeter) -Aaron > I was on vacation recently and stopped by a fireworks showroom. They had > refill fuse "e-matches" for an inexpensive fireworks firing console they [quoted text clipped - 19 lines] > > work, but I am sure there are many ways to do so. Plus they are SUPER > > cheap, so if you figure out a reliable way to use them, then great! Try this: http://www.fireworks.com/phantom%5Fmall/category.asp?cat=33 > Care to share your source? I need a new source as I'm down to only 4 > Oraxals (SP?) left in my stock. Each flight of my 1/2 scale Patriot [quoted text clipped - 18 lines] >> >> Anybody else seen these? Interesting.. How do you mount these? Have any pics closer up of what these things look like? These almost seem like the blank chips that you can get from firefox. > Try this: > [quoted text clipped - 16 lines] > >> > >> Anybody else seen these? > Interesting.. How do you mount these? Have any pics closer up of what > these things look like? > > These almost seem like the blank chips that you can get from firefox. What's the secret to using the Firefox chips? I made up some and one burned out my MAD unit. Richard Galejs sent me a power chip to fix it though. When I connected up one of the "ematches" to a plain battery it fired but like I said, it burned out my previously functioning MAD unit. I'm sticking to ematches for now. M-teks work good in all my tests and are still available. Kurt >> Interesting.. How do you mount these? Have any pics closer up of what >> these things look like? [quoted text clipped - 8 lines] > but like > I said, it burned out my previously functioning MAD unit. The IRF 7101 used in the output of this and other units is somewhat fragile. The AltAcc uses it and I have used mine since 1999 without any trouble. The secret I think is that the e-match opens up quickly. If you look at the data sheet for the IRF7101 you will see that it is very limited by heat dissipation. It is so small that any significant current for more than a few tenths of a second will kill it. From what I have seen of the MAD units, they use a capacitive discharge system. This limits the energy and you shouldn't have had any trouble even with a dead short on the output. Unless the series resistor to the capacitor were something like a 0R0. > I'm sticking to ematches for now. M-teks work good in all my tests > and are still available. > > Kurt  SignatureDavid W. Schultz http://home.earthlink.net/~david.schultz/ Q. Where am I? A. You can't get there from here. Hey Chuck, I bought a box and testfired two. Even put cannon fuse in one with no ignition. Did you pry the chip out of that plastic carrier in order to put it in a canister? Does this thing need something of a booster to get to work? Kurt Savegnago > Try this: > [quoted text clipped - 22 lines] >>> >>>Anybody else seen these? Hey Kurt, No, I did not pry the chip out. I separated the two pieces of the clip (removed the small rubber band and lifted the top off). The breakdown of the tests I performed are as follows: Test #1 - (5) E-matches 1. Separated the "bundle" into individual twin lead e-matches. 2. Disassembled the clips by removing the rubber band and lifting the top off. 3. Attached lead ends (stripped) to my RRC2 outputs (I did double the lead end and twist to give it a larger surface area). 4. Turned on my RRC2 and activated the output test. 5. E-match connected to Apogee/Drogue outputs fired after 10 seconds followed by the Main (by firing, I mean I can visibly see the filament burn/flash). Test #2 - (5) E-matches 1. Separated the "bundle" into individual twin lead e-matches. 2. Disassembled the clips by removing the rubber band and lifting the top off. 3. Attached lead ends (stripped) to my RRC2 outputs (I did double the lead end and twist to give it a larger surface area). 4. Placed the e-match end in a WD-40 cap. 4. Poured a small amount of black powder in the cap until about 1/2 the clip body was covered. 5. Turned on my RRC2 and activated the output test. 6. E-match connected to Apogee/Drogue outputs fired after 10 seconds followed by the Main. I also tested (2) with a PML Co-Pilot altimeter (same basic design as the RRC2) with the exact same results. What are you testing them with? I assume you can see the small spring shaped filament in the clip? Did you check for continuity before testing? Chuck > Hey Chuck, > [quoted text clipped - 33 lines] >>>> >>>>Anybody else seen these? Thanks for the specifics Chuck. Always good to have some alternatives on hand. I tested only two using a 12v. battery and I was able to do a continuity check with one of them. I think I'll just open one of them and pour a little 4F on it and repeat the test at a distance. I was expecting a visible flash but didn't notice anything. Kurt > Hey Kurt, > [quoted text clipped - 71 lines] >>>>> >>>>>Anybody else seen these? >Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. >$1.99 gets you a whole string of them at Target. That's about the price [quoted text clipped - 3 lines] >TRA#5512 >IEAS#75 Hey Ted, hope your rockets aren't worth much more than that because I've seen a lot of Xmas bulbs not work. Phil >> Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. >> $1.99 gets you a whole string of them at Target. That's about the price [quoted text clipped - 8 lines] > > Phil Before I even think of using xmas bulbs on flights there WILL be some serious ground testing. If that fails then it's no to xmas bulbs. I haven't worked out all the details yet but small glow plugs could have some promise. Ted Novak TRA#5512 IEAS#75 Ground testing isn't really gonna help with Christmas Bulbs because ground testing isn't representative of flight contitions. The filament on the christmas bulb is pretty weak and not soldered on, so that is one place where the stress of flight can cause a failure. Another is the bulb coming un-seated. Ground testing, while smart if you are trying to figure out how much BP to use, isn't going to be able to account for those things. And the one I used on my 3" Thor failed on an I211. I imagine it would have failed on a J350 or 570 as well. Your best bet is to test the charges in flight as a backup to whatever e-matches you have installed. Really, you just want to make sure that you get them to fire with a high rate of success, so maybe stick 1/2 gram or 1 gram of powder in them or something. > >> Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. > >> $1.99 gets you a whole string of them at Target. That's about the price [quoted text clipped - 18 lines] > TRA#5512 > IEAS#75 I've used Christmas bulbs with great success. The key is to use more than one for each ejection charge. I normally use 2 bulbs per charge for redundancy, but based on the canister size, one could use 3 or 4. It's not much more work to add more if desired. It's much less work and costly than replacing a rocket. I also use ematches, and I always use at least 2 for each charge for the same reason. Kevin > Ground testing isn't really gonna help with Christmas Bulbs because > ground testing isn't representative of flight contitions. The filament [quoted text clipped - 9 lines] > you get them to fire with a high rate of success, so maybe stick 1/2 > gram or 1 gram of powder in them or something. Have you ever actually seen the filament break in flight conditions? I've flown christmas bulb charges with over 200 flights, including a K1275 and M4000, and only had 2 failures, both of which I figured out the cause and neither was due to the filament breaking. On one, I had left too much air in the charge and the BP wasn't touching the filament when the current flowed. Now I always pack a bit of flameproof wadding in the end before taping. On the other, the leads of the bulb had corroded enough to inhibit the current and prevent firing. Now I lightly rough up the leads with sandpaper if the bulbs have been stored for a while. I have had no failures since instituting those changes. Contrary to what others say, I also have had success with up to 5g charges (in a 7.5" rocket with shear pins). The size of the shrink-wrap tubing needs to be increased significantly the more BP you plan to put in. If you use a long thin tube of BP, the BP furthest from the filament will be blasted away without burning. Don't let people tell you that christmas bulbs won't work. Try it, and think carefully about the failure modes, and you should have great success. -- David > Ground testing isn't really gonna help with Christmas Bulbs because > ground testing isn't representative of flight contitions. The filament [quoted text clipped - 33 lines] >> TRA#5512 >> IEAS#75 >Have you ever actually seen the filament break in flight conditions? I've >flown christmas bulb charges with over 200 flights, including a K1275 and [quoted text clipped - 15 lines] > >-- David E matches are not going to have corroded leads. How many ematches can you buy @ $2 vs crashing a $1000 rocket? You be the judge. Oh and if you ever see me at RSO and I find out you have bulbs, you will have a problem. Someone else might let them slide - that's their prerogative. Phil >>> Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. >>> $1.99 gets you a whole string of them at Target. That's about the price [quoted text clipped - 18 lines] >TRA#5512 >IEAS#75 They'll work fine on the ground. Also you won't launch unless your altimiter tells you you have good continuity. Where I think people have problems is with G force on take off, charges also contribute to the stress in the filament, the main charge gets a jolt when the drouge deploys and when the charge for the drouge blows. I'm not saying they always fail but they fail to often for my taste. Phil >>>> Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. >>>> $1.99 gets you a whole string of them at Target. That's about the [quoted text clipped - 29 lines] > > Phil Phil Isn't there a problem with some of the newer bulbs because they have a shunt that keeps all other light burning when one goes out in the string? Thought I read this somewhere when I was thinking of using them. Made me nervous. SignatureWilliam Richardson ENC USNR Ret. TRA 8703 L2 Do not laugh at the difficulties of others as you may soon have difficulties of your own. >>>>> Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. >>>>> $1.99 gets you a whole string of them at Target. That's about the [quoted text clipped - 33 lines] >Thought I read this somewhere when I was thinking of using them. Made me >nervous. Damn - that's enough to make me more nervous. THat shunt would make an open filament appear to the altimiter as though it were good. Come on you guys - $20-$500 for propellant. At least a similar amount for casing. $100-$200 per altimiter. $100 and up for the rocket. Spend $2 on a friggin ematch!! Phil >>>>>>Once my supply of 28B's are gone I'm going to give xmas bulbs a shot. >>>>>>$1.99 gets you a whole string of them at Target. That's about the [quoted text clipped - 43 lines] > > Phil Aaaahhh Phil, You're 125% correct here. Last I heard, Performance Hobbies still sells M-teks and one can go to Quickburst.net and get Cosmos ematches for a $1.00 apiece. I dorked a MAD unit on a ground test with a firefox ematch kit. Don't know what I did wrong but it ain't worth the trouble. Just buy commercial. Kurt >>>>>>> Once my supply of 28B's are gone I'm going to give xmas bulbs a >>>>>>> shot. [quoted text clipped - 56 lines] > > Kurt Of course he's right! I only mentioned alternatives as all I've been hearing is that nowadays a LEUP is required to purchase ematches(but not ignitors). Now I'm starting to wonder if that is true. Ted Novak TRA#5512 IEAS#75 >>>>>>>> Once my supply of 28B's are gone I'm going to give xmas bulbs a >>>>>>>> shot. [quoted text clipped - 66 lines] > TRA#5512 > IEAS#75 Ted, Last I heard those places were selling them and if one is nervous, stockpile some. I was playing with the firefox alternative too but didn't have any luck. These igniters look promising as mentioned by Chuck Neff up in one of the other replies. http://www.fireworks.com/phantom_mall/photo.asp?pid=882 One could just take a little pyrogen and dip them if they desire for a little extra insurance to light off the BP charge. I think a real major issue is finding a low current match one could reliably count on to light a motor off of a staging timer. M-tek is supposed to be coming out with one but I don't know what will be required to purchase those. Kurt THere seems to be a lot of inconsistencey between what dealers will or won't sell you without a LEUP. If one won't sell you ematches, try some other ones or share with a friend. Phil >Ted, > [quoted text clipped - 14 lines] > > Kurt > Well, I'm still working on my last box of Daveyfire 28B's so I'm pretty > set. That being said I used to use flash bulbs but those are VERY hard [quoted text clipped - 3 lines] > $1.99 gets you a whole string of them at Target. That's about the price > for one ematch, total bargain. Flashbulbs are still readily available at http://www.flashbulbs.com. Bill Cress is a very friendly, easy to work with kind of guy. >> Well, I'm still working on my last box of Daveyfire 28B's so I'm >> pretty set. That being said I used to use flash bulbs but those are [quoted text clipped - 6 lines] > Flashbulbs are still readily available at http://www.flashbulbs.com. > Bill Cress is a very friendly, easy to work with kind of guy. Nice seein' ya again Darrell! Actually I just got lucky and found a bunch at a local kick butt surplus store. Axman = mecca for rocket and robot stuff. Even picked up some nice 4" crdbrd tubes. http://ax-man.com/ Ted Novak TRA#5512 IEAS#75 > Nice seein' ya again Darrell! Nice to BE back. ;-) > Actually I just got lucky and found a bunch at a local kick butt surplus > store. Axman = mecca for rocket and robot stuff. Even picked up some > nice 4" crdbrd tubes. Surplus stores are the bomb. Whoops! Did I just say that? Run! It's the ATF! What size flashbulbs do you typically use? It's been years since I've used any, and I don't remember the size designations (last time I used them was in the early seventies along with some Centuri Sure-Shot igniters -- this was my cluster ignition method of preference...) David Erbas-White >> Well, I'm still working on my last box of Daveyfire 28B's so I'm >> pretty set. That being said I used to use flash bulbs but those are [quoted text clipped - 6 lines] > Flashbulbs are still readily available at http://www.flashbulbs.com. > Bill Cress is a very friendly, easy to work with kind of guy. > What size flashbulbs do you typically use? It's been years since I've > used any, and I don't remember the size designations (last time I used > them was in the early seventies along with some Centuri Sure-Shot > igniters -- this was my cluster ignition method of preference...) I preferred Flashcubes (NOT Magicubes, they have their own charging mechanism) but many people, myself included, used the bulbs bearing the AG-1 designation. Both types have stiff wire leads rather than other flashbulbs that have twist-in connectors. There is an very detailed article on them at: http://www.rocketryplanet.com/content/view/204/38/ Darrell > I preferred Flashcubes (NOT Magicubes, they have their own charging > mechanism) but many people, myself included, used the bulbs bearing [quoted text clipped - 6 lines] > > Darrell Excellent, thank you! David Erbas-White >> http://www.rocketryplanet.com/content/view/204/38/ > > Excellent, thank you! Glad to help. If anyone has any similar articles or documentation of hobby rocketry techiques or tips, I would be happy to publish them for the community. Once I run out of Oxrals, I was going to try some of Quickburst's Cosmos matches. Lookee here http://www.quickburst.net/ematch.htm Joe Michel > Why won't anyone respond? I realize that I'm not a regular poster, but I > do frequently visit the group. There can be good info. found here at [quoted text clipped - 9 lines] >> TRA #7915 L3 >> NAR 74595 L3 >"J.A. Michel" wrote > Once I run out of Oxrals, I was going to try some of Quickburst's Cosmos > matches. Lookee here http://www.quickburst.net/ematch.htm > Joe Michel Joe- I've used most all of Quickburst's offerings, from igniters to ematches. Thusfar I've nothing but praise. The quality and the service is first-rate. David even accepts Paypal. Kevin > Is my understanding correct that in order to obtain/possess e-matches (such > as Davyfires, Oxrals, M-TEK's, etc.) that you must have a LEUP? If so, what [quoted text clipped - 5 lines] > TRA #7915 L3 > NAR 74595 L3 > > Is my understanding correct that in order to obtain/possess e-matches (such > > as Davyfires, Oxrals, M-TEK's, etc.) that you must have a LEUP? If so, what [quoted text clipped - 5 lines] > > TRA #7915 L3 > > NAR 74595 L3 Little bit of self promotion here but take a look at Newtons3rdrocketry.com and select products. We have a ejection solution based on 48 gauge Nichrome bridge wire on a PCB substrate. Much like an ematch without the pyrogen. Come in a prepackaged ecan with either a 2 or 5 gram capacity. Very robust and the small ones are ~ $1.00 > Little bit of self promotion here but take a look at > Newtons3rdrocketry.com and select products. We have a ejection solution > based on 48 gauge Nichrome bridge wire on a PCB substrate. Much like an > ematch without the pyrogen. Come in a prepackaged ecan with either a 2 > or 5 gram capacity. Very robust and the small ones are ~ $1.00 Have these been tested using a PerfectFlite MAWD set up for dual deployment? > > Little bit of self promotion here but take a look at > > Newtons3rdrocketry.com and select products. We have a ejection solution [quoted text clipped - 3 lines] > > Have these been tested using a PerfectFlite MAWD set up for dual deployment? Yes they have using a duracell 9V |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.