#21
|
||||
|
||||
Quote:
__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR |
#22
|
||||
|
||||
Quote:
My friend Keith Sanders lives in a small town in rural France, and he was interested in starting in model rocketry last year (at age 71!) but unsure of what he would need. I had a Quest starter set, a few rocket kits, and extra motors sent to him, and (recently) an Estes Manta II launch set (with a 3/16" Maxi-Rod-compatible Porta Pad II, plus a Maxi-Rod for the SpaceX Falcon 9 kit I had sent to him) because they were low-priced and because he can get the 9 volt and AA batteries for their launch controllers locally. In addition: He has since bought more motors, wadding, and accessories from various European vendors, now that he knows what goes with what. (He had no misfires, recovery failures, or lost or damaged rockets during his first flying session [at a nearby neighbor's farm] last summer, which was wonderful!) It was a little neighborhood event, and his French neighbors were impressed. He is planning another flying session for when it gets warmer, and I sent him a couple of boost-glider kits, a SpaceX Falcon 9 kit (and D12-5s from Sierra Fox Hobbies), and an older Manta II launch set containing a "D"-compatible Porta Pad II, plus a Mxi-Rod. For flying the Falcon 9 on E9-6 motors, the Porta Pad II plus a "stretched-leads" Electron Beam launch controller will suffice.
__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR |
#23
|
||||
|
||||
Quote:
Apogee Components offers the Sky Launch Pad and Launch Controller (see: https://www.apogeerockets.com/Launc...m?cPath=12_172& ), which is very similar to the old yellow Estes Porta Pad and the old blue Estes Electron Beam, except that the Sky unit uses an LED instead of a light bulb. The launch pad, curiously, uses a *three-piece* 1/8" (it might be 3 mm) diameter launch rod.
__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR |
#24
|
||||
|
||||
I have an old Estes "Big Foot" pad I occasionally use with a standard launch controller, not the D-cell garbage batteries in the base. It actually is far more stable than the regular Porta-Pad and the "E" Porta-Pad due to its low center of gravity and its FOUR legs.
__________________
When in doubt, WHACK the GAS and DITCH the brake !!! Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't ! Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY. ALL systems are GO for MAYHEM, CHAOS, and HAVOC ! |
#25
|
||||
|
||||
Quote:
I can understand objecting to the greater size and weight of a 4-D battery power supply. But unless the Big Foot launch system had some design flaw (such as lousy battery contacts that made it unreliable, and I've never read or heard any complaints about its reliability), it fulfilled its purpose--firing many rockets, including large ones, on one set of D batteries--very well. With a switch-selectable relay ignition feature incorporated into it (using a separate Electron Beam controller to trigger a relay in the Big Foot's base, allowing its four D batteries to ignite clustered motors [because the pad's ignition leads would be *very* short, having an almost negligible voltage drop]), an updated Big Foot launch system would be even more versatile. Its hand-held controller could be a modified Electron Beam controller (or a new design) with a bypass switch, so that either its own internal AA batteries (or internal 9 volt battery) *or* the pad's D batteries could be used to ignite single motors. (The relay mode could ignite single motors, too, but that would draw current from all of the batteries needlessly--although it ^would^ fire them instantly! :-) )
__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR |
#26
|
||||
|
||||
Quote:
At the risk of speaking out of turn, it's probably because 4 "D" cells would still only generate 6 volts of power... and the fact that dry cells have a lot of internal resistance and aren't great at delivering large amounts of power. Other types of batteries are far superior with much lower internal resistance. Clustering batteries to deliver 12 volts results in faster and more reliable ignition and is easily far superior to 6 volt systems... At least that's the reasons why I argued for a larger assembly of "D" cells and the option to power it externally from an outside battery source... Hopefully GH will chime in with his own observations and views... Later! OL J R
__________________
The X-87B Cruise Basselope-- THE Ultimate Weapon in the arsenal of Homeland Security and only $52 million per round! |
#27
|
||||
|
||||
Quote:
The old Estes Electro-Launch system had provision for connecting a second battery pack (another Electro-Launch pad base containing four D batteries) to the "stock" Electro-Launch system (for a total of eight D cells), for igniting clustered motors. (The old Astron nichrome igniters, which were all they had back then, also made the extra 4-D battery pack desirable, especially for igniting clusters.) Even for igniting single Astron igniters, four D cells were probably the minimum practical power source; the Astron igniters would have quickly exhausted the four AA batteries (or a 9 volt battery) in a self-contained, hand-held launch controller. The Solar Igniter (and the later Quest and Aerotech igniters) was a truly revolutionary innovation in our hobby, which younger model rocketeers may not fully appreciate (I'd put igniter plugs in that category, too). Also: Four D cells will carry the burden of a school or Scout or club launch session that involves dozens of launches, though. A launch controller that uses 4 AA batteries or a 9 volt battery would give out much sooner. For higher voltage (and current), a LiPo battery pack could be installed in the Big Foot launcher base instead of four D batteries.
__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR Last edited by blackshire : 03-27-2016 at 10:55 PM. |
#28
|
||||
|
||||
Anything short of a fully-charged 12V wet-cell I find inadequate for launching.
I want instantaneous high current for oodles of 4+engine clusters. A 7Ah sealed wet-cell weighs very little and has tons of launching power. I find 6V worth of ANY dry-cells to be a BAD joke for a power system for anything but single BP engines. A good well charged 12V wet-cell can use BARE NICHROME in clusters for reliable instant ignition of BP motors.
__________________
When in doubt, WHACK the GAS and DITCH the brake !!! Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't ! Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY. ALL systems are GO for MAYHEM, CHAOS, and HAVOC ! |
#29
|
||||
|
||||
Quote:
I agree... might be "overkill" in some people's minds, but I prefer "overkill" to underkill any day of the week... There's a reason I soldered lamp cord leadouts to the battery contacts in all my Estes controllers years ago... Later! OL J R
__________________
The X-87B Cruise Basselope-- THE Ultimate Weapon in the arsenal of Homeland Security and only $52 million per round! |
#30
|
||||
|
||||
Quote:
Doug .
__________________
YORF member #11 |
Thread Tools | Search this Thread |
Display Modes | |
|
|