Many RSOs (including me) request that the ignitor be out of the motor before it is checked. With small motors, I would probably let it slide if the flier told me they were having problems.
Phil
Where I live, we have some geckos that come out at night during the summer. I noticed that they will crawl toward the laser spot. I guess they think it is a bug.
It might seem like a silly rule for igniters like Estes igniters and AeroTech Copperhead and FirstFire igniters, but when you consider all of the ignition options that exist then it becomes less of a silly rule.
Without a source of electricity, high current igniters like AeroTech Copperhead and FirstFire igniters will not accidently fire. Igniters built around an ematch, however, can accidently ignite under the right, but rare, circumstances when electricity is not connected to the igniter leads.
The situation becomes more complex with head-end igniters.
I want to see something more substantial (and substantiated) than "I heard". Where is the data?
ModRoc RMS motor instructions say to install the Copperhead igniter before installing the nozzle. Even the 29mm G64's.
I know. It doesn't change anything for me. Thanks for mentioning it.
Phil
I thought the newer HPR reloads have these regular nichrome igniters.... thats only on HPR motors?
I've seen it, too. I still never install the ignitor until I take it to the pad.
I stopped using Copperheads in favor of Firestar ignitors. I never had one fail on me, and the smallest ones fit easily into an Aerotech C-slot. I have used them successfully in 18mm reloadable motors.
Bill Sullivan
Phil Ste> I know. It doesn't change anything for me. Thanks for mentioning it. >
Yes, the HPR motors have a real igniter in them. The mid-power SU motors and reloads have copperheads.
Joe Michel
The G79W & G77R comes with Firstfire ignitors too...
Those use the 'standard' 29mm casings, not the 'hobby' 29mm casing. The 'hobby' ones use copperheads, but the ones that use different length casings come with the FirstFire igniters.
David Erbas-White
Andy Eng wrote:
True -- But the G motor isn't HPR either, eh? It's all a blur anyway...
BTW - You asked if anybody's done velcro strength testing. My office buddy did so a few months ago during the post Columbia standdown. Velcro's everywhere to hold down everything like notepads, pencils, calculators, sunglasses, etc. Just wanted to make sure the stuff didn't let go during ascent. The gist was that the sep-force varied alot depending on if you were peeling apart or pulling in tension. Pure shear was pretty stout too. The separation impulse F/dt was probably the next factor. Fresh & old doesn't matter so much as how often you pull it apart. We've got some gripless velcro attachments inside station that had simply wore out.
For recovery systems, I'd guess no more than about 1/4-1/2 inch of overlap & 1/2" wide is a reasonable starting point. I use the stuff by the rolls to hold down my guitar pedals and keep mic cables neat in the studio and at shows. May give it a try with rockets someday.
Fun stuff...
Best, Andy
So you're enforcing a rule that is not required by law or safety code because _you_ think it is a good idea?
Do you work for the ATF?
I still want to see the data substantiating the claims that ignitors go off spontaneously. I have several boxes of various e-matches and ignitors, have had for years, and have yet to have one "go off" sitting in my range box.
Phil is not the only one that uses and enforces the no igniter installed rule at the RSO table, for composite motors.
BTW, why would you ask the ATF question? Was it a joke -- didn't see a smiley face??
Fred
Thomas Koszuta wrote:
This is what was said:
"Igniters built around an ematch, however, can accidently ignite under the right, but rare, circumstances when electricity is not connected to the igniter leads."
I'm sorry that you do not understand "rare circumstances"? If you want to know what the rare circumstances are, do a Google search or talk to a blaster. If you don't like the word "rare", how about "unlikely to be encountered by the rocketry hobbiest or pyrotechnician"?
By the way, ematches are regulated by the ATF. They should not be stored in your range box.
That_is_right. If you don't like it, wait untill someone else is RSO.
No I don't.
If you don't like it, you can be RSO. If a motor goes off in your face, I'll be the guy laughing.
Phil
I haven't seen it either. That doesn't mean it hasn't or couldn't happen. If I spend several hours of my day volunteering, I expect - no demand a little consideration. If someone else wants to do it so I don't have to, they are VERY welcome.
So I'm wondering if "Mister Are DO You Work For The ATF" spends at least a few volunteering at every launch.
Phil
Phil,
How about monotube hybrids, which must be assembled with the igniter in place? Since it's not an assembled engine until the N2O is added, will you inspect them with the igniter in place?
Kevin OCassen
As I mentioned in my original post, I can be flexible. You mention a valid reason. - But don't tell the guys that accuse me of working for ATF. I'm way less likely to be flexible with one of them - unless they give me what I consider a valid reason to be. And that is a capital / bold / emphasized I - like it or not. I don't look to bust balls - just to minimize the possibility of bad things happening.
SO; how many people put an ignitor in before the rocket is vertical?
How many people put clips on their ignitor before the rocket is verticle?
How many people short the clips together berfore they clip onto the ignitor?
Did you know that a relay can be stuck in a way that will put power to the ignitor as soon as you touch it with the clips. This can be cause by a mechanical malfunction or from the contacts getting welded together.
Phil Phil
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