"E" motor-compatible pads?

[blackshire]

Hello All,

I see that Estes' Porta Pad II is recommended for rockets up to "D" power (using a 3/16" diameter Maxi-Rod, of course), while they recommend their E-Launch pad (which can incorporate a 3/16" or 1/4" launch rod) and E-Launch controller for rockets using "E" and more powerful motors (up to the model rocket limit for "low G" impulse, I think). This raises a question:

The SpaceX Falcon 9 kit uses Estes D12-5 and E9-6 black powder motors. Could the Falcon 9 model, when powered by an E9-6 motor, be safely launched from the Porta Pad II (using a 3/16" Maxi-Rod), particularly if the Porta Pad II was weighted (or if its legs were tied to stakes in the ground)? Also:

The reason why I ask is because I had a SpaceX Falcon 9 kit and an older Manta II launch set (which came with a Porta Pad II) sent to a friend of mine, along with a 3/16" Maxi-Rod and some D12-5 motors for use with the Falcon 9 model (plus some 18 mm motors for the Manta II rocket). The E-Launch pad and E-Launch controller are rather expensive, but I think the Porta Pad II and the Electron Beam launch controller (whose 15' ignition leads are, I think, long enough to be safe with E9-6 motors) would work just fine for this and similar E9-6 applications. Many thanks in advance to anyone who can help!

[chalinaty]

According to the NAR Safety Code, motors larger than D require a 30' safe distance. That would mean that using the Electron Beam would violate this policy.

[blackshire]

According to the NAR Safety Code, motors larger than D require a 30' safe distance. That would mean that using the Electron Beam would violate this policy.Thank you--while I knew that a "30' ignition leads rule" kicked in at some impulse level, I didn't know where the dividing line was. He's in France, so the NAR's rules may not apply (but the equivalent space modeling governing body there could very well have a similar rule, although even fuse ignition is rather common in European model rocketry...). But:

I can easily make up a set of 15' extension leads to go with his Electron Beam launch controller. (Both the Electron Beam controller and the E-Launch controller use four "AA" batteries, so the additional 15' of leads shouldn't cause any single-motor ignition problems, especially if I make the extension leads out of larger-gauge wire.) I don't think the Porta Pad II will be a problem with an E9-6 powered Falcon 9 model, as I've launched the large and heavy double D12-3 powered Cox Saturn V from a Maxi-Rod equipped Porta Pad several times, and the pad was steady.

[ghrocketman]

I have launched models up to 16oz off a standard Estes Porta-Pad using the following engines over a D12.
E9, E12, E16, E18, E28, E30, F15, F24, F32, F39, F52 and even an old FSI F100.
I however would NOT reccommend launching anything over an E18 without staking the legs down and using a STIFF one-piece stainless 3/16" rod. Even then you get some serious rod-whip.
I use my Estes Porta Pad E's mostly now instead for even 1/8" rods with the right adapters.
I have launched MUCH higher impulse motors than full 80 n-sec F's off the Estes "E" porta pad.
I won't show the max I have flown off of it but suffice it to say it did NOT comply with current NAR high-power rules and was well over 160 n-sec total impulse and over 200 newtons average thrust but that was MANY years ago.
I also have a Saw-horse based home-brew 5-station "multi pad".
Using the E-pad for all G's except Warp-9 propellant should suffice.
I liked the old Estes original pro-series pad although it was way overpriced, just as the Aerotech Mantis is also. The Aerotech pad is actually kinda weak in certain areas.

[blackshire]

I have launched models up to 16oz off a standard Estes Porta-Pad using the following engines over a D12.
E9, E12, E16, E18, E28, E30, F15, F24, F32, F39, F52 and even an old FSI F100.
I however would NOT reccommend launching anything over an E18 without staking the legs down and using a STIFF one-piece stainless 3/16" rod. Even then you get some serious rod-whip.
I use my Estes Porta Pad E's mostly now instead for even 1/8" rods with the right adapters.
I have launched MUCH higher impulse motors than full 80 n-sec F's off the Estes "E" porta pad.
I won't show the max I have flown off of it but suffice it to say it did NOT comply with current NAR high-power rules and was well over 160 n-sec total impulse and over 200 newtons average thrust but that was MANY years ago.
I also have a Saw-horse based home-brew 5-station "multi pad".
Using the E-pad for all G's except Warp-9 propellant should suffice.
I liked the old Estes original pro-series pad although it was way overpriced, just as the Aerotech Mantis is also. The Aerotech pad is actually kinda weak in certain areas.Thank you! I appreciate your posting this information, as I suspected that the launch pad recommendations were written with an "err on the side of caution" ('better safe than sorry') mindset, which I can't blame any model rocket manufacturer or hobbyist rocketry governing body for operating by. Due to the size of his flying field, at a nearby neighbor's small farm, E9-powered flights (or similarly-high flights with high-performance 18 mm models) are probably the limit at which he could still recover the rockets on the field (it's surrounded by woods), plus--due to common local cloud and wind conditions--E9 flights will be just occasional events for him. But the E9-6 in the Falcon 9 model does provide satisfyingly long-burning, high flights, particularly when the rocket carries a keychain video/still camera with sound to record the flights (see: www.youtube.com/watch?v=nY8Pe_w0mEs ), and even D12-5 powered flights with such a camera on a Falcon 9 are pretty impressive (see: www.youtube.com/watch?v=dgvIkyWRBEc ). Also:

Even though the NAR Safety Code says to use a launch controller with 30' ignition leads with "E" and higher impulse motors, I don't think a CATO with a low-end "E" motor such as the E9-6 would be dangerous if one was using a launch controller with 15' ignition leads. I launched my 1990s-vintage Estes Cox Saturn V (which used two D12-3 motors, the aggregate equivalent of an "E" motor) using my old Astron II 12 volt launch controller, which had 15' ignition leads (and I don't recall--although admittedly it's been a while--any mention of using longer ignition leads in the model's instructions). I wouldn't use 15' ignition leads with any motor more powerful than an E9, though. As well:

Point well-taken regarding using one-piece launch rods, and on staking the pad's legs for use with E18 and higher-impulse motors. (Long ago, Estes offered a third extension piece for their two-piece 1/8" launch rod [they may have recommended it for their 1/70th scale Saturn IB and/or 1/100th scale Saturn V kits], which gave the rod a total length of 53"--but that always seemed like it would have excessive whip!) I switched to even a 1/8" one-piece rod after rod-whip with a two-piece rod resulted in a few "corkscrew" and overly-weathercocked flights on breezy days; the one-piece rod cured the problem. (Had I flown anything heavier/more powerful than the Cox Saturn V, I would have gotten a one-piece 3/16" launch rod.) If he expresses interest in flying heavier rockets using higher-impulse "E" motors or anything more powerful, I'll recommend that he get a one-piece 3/16" rod at a hardware store the next time he visits the UK, which he does regularly (his local hardware stores in France might have only hard-metric size [5 mm, 6 mm, etc,] music wire rods). And:

I agree with you about the Mantis launch pad. I've seen one, and while it does work, it has a higher center of gravity than it needs to have, which makes longer support legs necessary, which in turn makes the whole pad bulkier and heavier than it could be. I never had one of Estes' Big Foot launch pads, but its four legs and very low center of gravity probably made it very stable even with long, heavy rockets on it. I believe it used "D" batteries that were housed in the pad base. An updated version could optionally also use those batteries as part of a relay launch system (used with another, self-contained hand-held launch controller powered by its own four "AA" batteries or a 9 volt battery), for igniting clustered motors *without* having to use a car battery.

[luke strawwalker]

Thank you--while I knew that a "30' ignition leads rule" kicked in at some impulse level, I didn't know where the dividing line was. He's in France, so the NAR's rules may not apply (but the equivalent space modeling governing body there could very well have a similar rule, although even fuse ignition is rather common in European model rocketry...). But:

I can easily make up a set of 15' extension leads to go with his Electron Beam launch controller. (Both the Electron Beam controller and the E-Launch controller use four "AA" batteries, so the additional 15' of leads shouldn't cause any single-motor ignition problems, especially if I make the extension leads out of larger-gauge wire.) I don't think the Porta Pad II will be a problem with an E9-6 powered Falcon 9 model, as I've launched the large and heavy double D12-3 powered Cox Saturn V from a Maxi-Rod equipped Porta Pad several times, and the pad was steady.

Yes, it can be done... as you said, weight down the legs or pin them to the ground with spikes or long coat hangers or something bent into a "U" shape and pushed deeply into the ground, preferably at an angle, to pin the legs down (I prefer weight myself if I were doing that). Better yet build your own pad using wood and a tin can cut in half and turned inside out for a blast deflector, like my "Pad 34-Z ("Z" for "Zooch") which looks MUCH better and more realistic (ups the "cool" factor, plus the additional weight of a 2x12 base two feet long provides enormous stability for anything powered by "model rocket engines" (it would need to be bigger for HPR, but that's beside the point-- I'm not interested in HPR).

IMHO their "recommendations" are aimed mostly at selling additional expensive pad and launch control gear. The "E" controller is a rather shabby controller IMHO-- it still uses the dinky bell wire (just more of it for longer leads) and the crummy "AA" batteries to provide power... I rebuilt all my Estes controllers (which are all at least 30 years old... an old "Electron Beam" back when you had to assemble them yourself, from my first starter set, and a "Pola-Pulse" that used the old flat Polaroid batteries (which were just as lousy as AA's IMHO, and much more difficult to find and more expensive to boot). I soldered in lamp cord from the dollar store and a pair of battery charger clamps to connect it to a car battery (raise the hood) or better yet a car battery jumper pack (much more portable). Unlimited launch power for anything you want to fly then. I also replaced the stupid dinky bell wire with lamp cord from the dollar store and soldered on some copper microclips I bought at Radio Shack years ago. This reduces the resistance considerably. I have since installed regular 110 volt "replacement plugs" on the lead-out from the controller about a foot down the wire-- this makes the controller more compact to store in the range box, and allows a regular 25 foot extension cord to be used for the launch leads. The microclips are still on lamp cord about 5 feet long, equipped with a plug to plug into the extension cord. I also dumped the stupid flashlight bulbs they originally came with for continuity, and replaced them with LED's equipped with current limiting resistors, one that burns whenever the battery is hooked up with a good connection, and the other lights when the key is inserted. I also made my own keys using solid Romex house wire... cut a piece about 2-3 inches long, strip the insulation off it, straighten it out, and curl one end around into a "loop" using a pair of pliers, and solder the loop closed... instant launch key and it gets MUCH better contact with less resistance than steel launch keys the controllers come with, which are prone to corrosion as well.

Of course this is all probably a lot more trouble than you want to go to... If you don't want to modify the controllers but still get the extra distance "required" for E motor setbacks, simply get a roll of lamp cord from the local "Dollar Store" (which can be had for about a buck or two) and solder on a pair of micro-clips to connect to the ignitor. Simply clip the existing controller microclips onto the extension wires (strip them back about a half-inch and twist the wires... make sure the clips don't touch of course and cause a short circuit...) Then simply use the existing AA powered launch controller as normal... It'll be every bit as good as the expensive "E" controller... To ensure that the leads don't touch and short out, a piece of large "heat shrink tubing" can simply be slid over one clip once the extension is hooked up to provide a barrier between the two... or a piece of tape applied over one clip to isolate it from the other...

Later and good luck! OL J R :)

[luke strawwalker]

I have launched models up to 16oz off a standard Estes Porta-Pad using the following engines over a D12.
E9, E12, E16, E18, E28, E30, F15, F24, F32, F39, F52 and even an old FSI F100.
I however would NOT reccommend launching anything over an E18 without staking the legs down and using a STIFF one-piece stainless 3/16" rod. Even then you get some serious rod-whip.
I use my Estes Porta Pad E's mostly now instead for even 1/8" rods with the right adapters.
I have launched MUCH higher impulse motors than full 80 n-sec F's off the Estes "E" porta pad.
I won't show the max I have flown off of it but suffice it to say it did NOT comply with current NAR high-power rules and was well over 160 n-sec total impulse and over 200 newtons average thrust but that was MANY years ago.
I also have a Saw-horse based home-brew 5-station "multi pad".
Using the E-pad for all G's except Warp-9 propellant should suffice.
I liked the old Estes original pro-series pad although it was way overpriced, just as the Aerotech Mantis is also. The Aerotech pad is actually kinda weak in certain areas.

The Mantis can be a DISASTER...

At a launch out here a few years ago, one of the club members used his Mantis pad to launch a large model rocket with a G motor... the rocket chuffed a few times and kicked the pad around, then finally ignited and came up to pressure-- just as the "lean over" feature of the Mantis turned loose and the rod tipped over toward horizontal... the rocket took off at about a 45 degree angle and blew the pad completely over... we all "puckered up" and held our breath as this rocket roared completely over the farm and over the neighboring place, apparently headed directly towards impacting a mobile home next door. Thankfully it went "long" and impacted in the drainage ditch behind their place...

If you're going to use a Mantis for big motors, I highly recommend you inspect the "lean over" feature and make sure that everything is tight and can stand up to the force of launch...

Later! OL J R :)

[blackshire]

Yes, it can be done... as you said, weight down the legs or pin them to the ground with spikes or long coat hangers or something bent into a "U" shape and pushed deeply into the ground, preferably at an angle, to pin the legs down (I prefer weight myself if I were doing that)...[SNIPPED only for brevity]...Of course this is all probably a lot more trouble than you want to go to... If you don't want to modify the controllers but still get the extra distance "required" for E motor setbacks, simply get a roll of lamp cord from the local "Dollar Store" (which can be had for about a buck or two) and solder on a pair of micro-clips to connect to the ignitor.As a mentor of your cinematographic namesake famously said, "Your insight serves you well." :-) Tiring more quickly these days, I go for the SIB ("Simplest Is Best") solutions to such problems. A 15' length of dual-conductor lamp cord (equipped with micro-clips on the launch pad end, and solder-"tinned" bare leads on the other) will work nicely. Using a large, two-screw terminal connector block (which I have) might be even better than using tinned leads, because the Electron Beam controller's micro-clips could be connected to the terminal block's "flange-insulated" flat pigtail leads without accidentally shorting anything.

[ghrocketman]

I don't know if you are old enough to remember how loud a real M-80/ Silver Salute/Cherry Bomb is or how loud the 'bootleg' ones prior to 9/11 were (now very hard to find due to the ridiculous explosive regs now, but that's a whole other ridiculous subject) or how loud a Peacock Cracker Bomb is (legal if you have the proper pyrotechnic permits still), but a max cato of an E9 can be as loud and you can feel a concussive shock wave even from 30 feet away.
An 'old school' FSI F100 max cato can be almost but not quite as loud/forceful as a "Quarter Stick" or "Block Buster" which is fairly serious.
Do I bother with 30' leads with E9's ?
Nah, and don't with anything under a G64 either.
I fly on private land, usually alone or with one other person and a dog....lol.

[blackshire]

I don't know if you are old enough to remember how loud a real M-80/ Silver Salute/Cherry Bomb is or how loud the 'bootleg' ones prior to 9/11 were (now very hard to find due to the ridiculous explosive regs now, but that's a whole other ridiculous subject) or how loud a Peacock Cracker Bomb is (legal if you have the proper pyrotechnic permits still), but a max cato of an E9 can be as loud and you can feel a concussive shock wave even from 30 feet away.
An 'old school' FSI F100 max cato can be almost but not quite as loud/forceful as a "Quarter Stick" or "Block Buster" which is fairly serious.
Do I bother with 30' leads with E9's ?
Nah, and don't with anything under a G64 either.
I fly on private land, usually alone or with one other person and a dog....lol.We made a few craters in our front yard in Miami with those (and there are still chips of granite shrapnel from a cherry bomb embedded in the walls in the garage there...). I'll make up a set of 15' extension leads for use with an Electron Beam for igniting E9-6s (I might take a slight risk with myself, but not with someone else).

[ghrocketman]

The only time I have had full-cato E9's were intentional ones that I turned into large firecrackers by smacking them several times on the side with an "engineer's hammer" to fracture/dislodge the propellant from the casing. Makes for a decent 4th of July 'salute' when nothing more decent can be found. Not quite as good as 'flash powder' real M80/Silver Salute/Block buster, but can still be heard several miles away. Naturally ignited by a cannon-fuse hot-glue sealed into the nozzle or a hole in the side.

[blackshire]

The only time I have had full-cato E9's were intentional ones that I turned into large firecrackers by smacking them several times on the side with an "engineer's hammer" to fracture/dislodge the propellant from the casing. Makes for a decent 4th of July 'salute' when nothing more decent can be found. Not quite as good as 'flash powder' real M80/Silver Salute/Block buster, but can still be heard several miles away. Naturally ignited by a cannon-fuse hot-glue sealed into the nozzle or a hole in the side.It did seem a bit odd to me that such a relatively low-impulse, end-burning motor as the E9-6 would go off like that without some help. :-) Actually, that would be a spectacular way to dispose of motors that one didn't want to risk flying in a valuable model (if they had been thermal-cycled, or were known to have been dropped on hard surfaces). Also:

A mixture of oxygen and acetylene in a black trash bag, ignited with a long (several feet) green cannon fuse taped to it, is even more explosive. A biker (motorcyclist) I met once when I was flying model rockets at Tamiami Park described having done this, using a 6' fuse. It was the cause of a mysterious incident late one night in Miami (with no discernable motive) which shattered windows facing the blast site (an intersection in a residential neighborhood) for blocks all around, but left no fragments. He said that the bag started to wrinkle in reaction to the mixture soon after he vented it from his oxy/acetylene torch, and that the noise of the blast was painful (he ducked behind his house after lighting the fuse and running). Needless to say, I've never been inclined to try this myself.

[ghrocketman]

That Oxy-Acetylene mix in the trash bag sounds like a real BLAST !

[blackshire]

That Oxy-Acetylene mix in the trash bag sounds like a real BLAST !Indeed--my father and I set off a few plastic sandwich bags filled with hydrogen/air mixtures (we used the lye & water with aluminum foil "hydrogen formula" in a bottle), and even those small quantities of hydrogen and air produced surprisingly powerful bangs!

[luke strawwalker]

As a mentor of your cinematographic namesake famously said, "Your insight serves you well." :-) Tiring more quickly these days, I go for the SIB ("Simplest Is Best") solutions to such problems. A 15' length of dual-conductor lamp cord (equipped with micro-clips on the launch pad end, and solder-"tinned" bare leads on the other) will work nicely. Using a large, two-screw terminal connector block (which I have) might be even better than using tinned leads, because the Electron Beam controller's micro-clips could be connected to the terminal block's "flange-insulated" flat pigtail leads without accidentally shorting anything.

There ya go...

I could see buying the "E" controller *IF* Estes would have actually made it a BETTER flipping controller, instead of a gimmicky (blue with slightly longer leads) version of the dinky standard starter set (yellow) controller they sell as "standard equipment" in starter sets and such... Make it powered by "D" batteries (or better yet a rechargeable RC battery pack) and with a port to plug in a simple lead-out to plug in a pigtail with car battery clips so it could be used with an outside power source, and some decent sized speaker wire or lamp cord 30 foot lead-out wires to the ignitor clips. Dumping the dinky flashlight bulb and switching to LED indicators would be another good step. Make it more like the old "Solar controller" of years past rather than the dinky AA powered things...

Same thing with the "E" Pad, which is just an upscale of their standard plastic wonder pad... IMHO they should have upscaled something like the old "Bigfoot" pad, put 8 "D" cells in the base for weight (with a port for external battery supply if desired), put a relay in it, and had a plug-in 30 foot lead controller designed to operate it from the requisite "large model rocket" setback distance... That would have been something that would actually be worth the money and more suitable to the job, capable of launching ANYTHING in the "large model rocket" class up to low-end HPR, and with a relay capable of firing clusters as well...

I mean, they had to make new tooling to make an enlarged E-Pad anyway, so WHY NOT make it something that is actually better suited to the size and weight and power of the rockets it's supposedly designed for, rather than a glorified upscale of the dinky standard 3 leg plastic pad from the starter kits, with a jakked up price??

Later! OL J R :)

[luke strawwalker]

Last fourth of July the nephews were taking plastic pop bottles and squirting some Lysol toilet bowl cleaner into them (strong hydrochloric acid-- I've used it to eat rust off nuts and bolts before) and then dropping in a wadded up piece of aluminum foil and screwing the lid on quickly and tossing it out onto the county road in front of their house... the chemical reaction liberates gas that rapidly overpressurizes the bottle and causes it to explode surprisingly loudly....

I like the looks of the "cremora bomb" myself... take a coffee can punch a little hole in the side and put some viscofuse in it and then dump in a thin layer of smokeless powder. Cover with a paper towel and then dump a bottle of powdered coffee creamer in on top of it and spread it around evenly. Set the can in a hole in the ground and backfill around it with dirt. Light the fuse and run... The gunpowder acts as a "lifting charge" when it goes off and blows the flammable coffee creamer into the air as fine dust particles and aerosolizes it, and acts as an ignitor to create a dust explosion/fireball...

Later! OL J R :)

[Initiator001]

If one is interested in a pre-made launch controller, the Estes PSII Launch Controller has 30' of cable and can be powered by six 'C' batteries or a LiPo battery pack.
It even has extra micro-clips for use with clustered motors.

[LeeR]

I can easily make up a set of 15' extension leads to go with his Electron Beam launch controller. (Both the Electron Beam controller and the E-Launch controller use four "AA" batteries, so the additional 15' of leads shouldn't cause any single-motor ignition problems, especially if I make the extension leads out of larger-gauge

You should be fine. I think the Estes controllers us 22 ga. wire. Here is the ohms/meter for several gauges of copper wire:

18 ga., .021
22ga., .053
26 ga., .134

I'd just add 18 ga. lamp cord since it's cheap. If my math is right, each side of your 15 foot extension adds about .1 ohm.

I modified an Electron Beam years ago and replaced the standard wire with 18 ga. lamp cord, terminated in a small box with banana jacks. I built up a bunch of 5 foot leads with banana plugs on one end, and micro clips on the other. I did this when I was doing school launches, and wanted easy to replace cords if they got really diirty. Easy to replace, and I could clean them later. I'd just use extension cords now, since they are cheap, and clip off the receptacle and add clips. Similarly, I'd put a receptacle in the box, rather than using banana jacks. But I did not want a modified extension cord with clips being used by students. Somebody would have plugged one into an AC outlet, I have no doubt. :)

I also added 18ga. lamp cord to connect to a 12V gel cell, rather than use the built-in AA batteries. And that meant replacing the lamp, so I epoxied on a small, round piezo buzzer over the lamp socket. Basically I kept the interlock and launch button!

I've since modified other Electron Beams, but mostly by just replacing the incandescent lamp with an LED.

[luke strawwalker]

You should be fine. I think the Estes controllers us 22 ga. wire. Here is the ohms/meter for several gauges of copper wire:

18 ga., .021
22ga., .053
26 ga., .134

I'd just add 18 ga. lamp cord since it's cheap. If my math is right, each side of your 15 foot extension adds about .1 ohm.

I modified an Electron Beam years ago and replaced the standard wire with 18 ga. lamp cord, terminated in a small box with banana jacks. I built up a bunch of 5 foot leads with banana plugs on one end, and micro clips on the other. I did this when I was doing school launches, and wanted easy to replace cords if they got really diirty. Easy to replace, and I could clean them later. I'd just use extension cords now, since they are cheap, and clip off the receptacle and add clips. Similarly, I'd put a receptacle in the box, rather than using banana jacks. But I did not want a modified extension cord with clips being used by students. Somebody would have plugged one into an AC outlet, I have no doubt. :)

I also added 18ga. lamp cord to connect to a 12V gel cell, rather than use the built-in AA batteries. And that meant replacing the lamp, so I epoxied on a small, round piezo buzzer over the lamp socket. Basically I kept the interlock and launch button!

I've since modified other Electron Beams, but mostly by just replacing the incandescent lamp with an LED.

One could always "reverse" the connections using 110 v extension cords and plugs... What I mean is, putting the MALE connector on the leadout from the launch controller, so the FEMALE end of the extension cord plugs into it, which leaves the MALE extension cord plug at the launch pad, into which a FEMALE plug end plugs into it with a pair of microclips attached to the wires coming out of it... No way to plug a female connector with a piece of wire and microclips on it into a 110 V outlet...

Other than the obvious question, where do you plug into 110 out on the launch field??

Later! OL J R :)

[LeeR]

Other than the obvious question, where do you plug into 110 out on the launch field??

Later! OL J R :)

We built rockets in the classrooms, and then launched on playground over several days. Everything was stored in the rooms between daily launches. Highly unlikely, although I could see a younger me putting an igniter between clips and plugging into the wall. :)

[blackshire]

We built rockets in the classrooms, and then launched on playground over several days. Everything was stored in the rooms between daily launches. Highly unlikely, although I could see a younger me putting an igniter between clips and plugging into the wall. :)Thank you for posting the wire gauge and length vs. resistance figures. I did that a couple of times when I worked at the Miami Space Transit Planetarium, when another console operator and I launched rockets between shows. We launched the rockets from the patio of our rooftop observatory, and I used a regular 120 volt extension cord, plugged into a wall outlet in one of the observatory bays when each countdown reached zero. The solar igniters lit with *no* perceivable ignition delay, of course! :-)

[blackshire]

If one is interested in a pre-made launch controller, the Estes PSII Launch Controller has 30' of cable and can be powered by six 'C' batteries or a LiPo battery pack.
It even has extra micro-clips for use with clustered motors.I've seen that one in AC Supply's www.acsupplyco.com catalog (their prices are very good), and it's a good one. I didn't go with it for reasons of cost, necessity (how often its capabilities would be needed), and utility (its size, its requirement for more batteries [6 "C" batteries] or for a LiPo battery pack that would have to be mail-ordered). Also:

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.

[blackshire]

There ya go...

I could see buying the "E" controller *IF* Estes would have actually made it a BETTER flipping controller, instead of a gimmicky (blue with slightly longer leads) version of the dinky standard starter set (yellow) controller they sell as "standard equipment" in starter sets and such... Make it powered by "D" batteries (or better yet a rechargeable RC battery pack) and with a port to plug in a simple lead-out to plug in a pigtail with car battery clips so it could be used with an outside power source, and some decent sized speaker wire or lamp cord 30 foot lead-out wires to the ignitor clips. Dumping the dinky flashlight bulb and switching to LED indicators would be another good step. Make it more like the old "Solar controller" of years past rather than the dinky AA powered things...

Same thing with the "E" Pad, which is just an upscale of their standard plastic wonder pad... IMHO they should have upscaled something like the old "Bigfoot" pad, put 8 "D" cells in the base for weight (with a port for external battery supply if desired), put a relay in it, and had a plug-in 30 foot lead controller designed to operate it from the requisite "large model rocket" setback distance... That would have been something that would actually be worth the money and more suitable to the job, capable of launching ANYTHING in the "large model rocket" class up to low-end HPR, and with a relay capable of firing clusters as well...

I mean, they had to make new tooling to make an enlarged E-Pad anyway, so WHY NOT make it something that is actually better suited to the size and weight and power of the rockets it's supposedly designed for, rather than a glorified upscale of the dinky standard 3 leg plastic pad from the starter kits, with a jakked up price??

Later! OL J R :)If Estes still has the molds for their Big Foot launch pad and launch controller (which had 4 "D" batteries in the pad's base, see: http://www.ninfinger.org/rockets/catalogs/estes79/79est56.html ), an updated version could have the relay ignition feature (for firing clustered motors, including for parallel-staged rockets) incorporated into it. Also, speaking of LED-illuminated launch controllers:

Apogee Components offers the Sky Launch Pad and Launch Controller (see: https://www.apogeerockets.com/Launch_Pads/Sky_Complete_Launch_System?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.

[ghrocketman]

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.

[blackshire]

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.I'm curious as to why you refer to its 4-D battery installation as garbage, as it should work just as well as the Solar and Electron Beam launch controllers' 4 AA batteries; in fact, four D cells should fire more igniters than four AA cells (and the Big Foot system was intended for such heavy-duty use) because of the D batteries' higher mAh capacity. (The Estes Electro-Launch pad with controller [see: http://www.ninfinger.org/rockets/nostalgia/69est086.html ] also used four D batteries, housed in the pad base.) Now:

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! :-) )

[luke strawwalker]

I'm curious as to why you refer to its 4-D battery installation as garbage, as it should work just as well as the Solar and Electron Beam launch controllers' 4 AA batteries; in fact, four D cells should fire more igniters than four AA cells (and the Big Foot system was intended for such heavy-duty use) because of the D batteries' higher mAh capacity. (The Estes Electro-Launch pad with controller [see: http://www.ninfinger.org/rockets/nostalgia/69est086.html ] also used four D batteries, housed in the pad base.) Now:

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! :-) )

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 :)

[blackshire]

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 :)I appreciate your courtesy, but observing one's turn is really only important in in-person situations (or ones occurring over remote audio links) that take place in real time. (I suppose it could be important in real time conversations in an online chat room, but I can't read or type postings rapidly enough to interrupt--or be interrupted by--another poster. :-) )

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.

[ghrocketman]

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.

[luke strawwalker]

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.

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 :)

[Doug Sams]

I agree... might be "overkill" in some people's minds, but I prefer "overkill" to underkill any day of the week... If one likes fiddlin' with clusters as I do, then a good 12V system is a must.

Doug

.

[Doug Sams]

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. I don't recall that option (not saying it didn't exist, tho) but there was a 4-to-8 cell upgrade kit which we acquired thereby converting our Electro-Launch to 12V. But all that meant was that, when we got ready to fly, we had a launcher with 8 dead batteries instead of 4 :(

A bit more seriously, 8 weak D cells could still fire nichrome and Astron (?) igniters, but 4 weak D cells wouldn't do squat.

So not long after the 4-8 upgrade, we bought the hookup kit to use the car battery instead. I can still vividly recall my dad pulling his 88 Olds down the driveway in our backyard so we could set up the pad just in front of it. RIP, Dad !

BTW, I'm still using that car hookup kit, but using it with a 12V gel cell.

Doug

.

[ghrocketman]

My main launch duties are still handled by two 40 year old Astron Launch controllers.
I use the same battery in my flight-box for my R/C planes that powers my RC power-panel, R/C fuel pump, and R/C Sullivan Hi-Tork starter.

[blackshire]

I don't recall that option (not saying it didn't exist, tho) but there was a 4-to-8 cell upgrade kit which we acquired thereby converting our Electro-Launch to 12V. But all that meant was that, when we got ready to fly, we had a launcher with 8 dead batteries instead of 4 :(

A bit more seriously, 8 weak D cells could still fire nichrome and Astron (?) igniters, but 4 weak D cells wouldn't do squat.

So not long after the 4-8 upgrade, we bought the hookup kit to use the car battery instead. I can still vividly recall my dad pulling his 88 Olds down the driveway in our backyard so we could set up the pad just in front of it. RIP, Dad !

BTW, I'm still using that car hookup kit, but using it with a 12V gel cell.

Doug

.Many memories of my father also involve him hooking up the 12 volt Estes FS-5 launch system http://www.ninfinger.org/rockets/nostalgia/69est086.html to the battery, in his 1965 Chevrolet Suburban. But I'm glad that the new low-current igniters freed us from dependence on big wet cell batteries; it's nice to be able to walk or bicycle to a flying site! Also:

I never had an Electro-Launch (we used Estes' wooden Tilt-A-Pad when I was growing up), but you're right that it could be converted to 12 volt operation by adding four additional D batteries (I hadn't read all of the hard-to-read [on my screen] text here: http://www.ninfinger.org/rockets/nostalgia/69est086.html ). Here's the additional battery pack (an extra Electro-Launch base, sans launch rod and blast deflector: http://www.ninfinger.org/rockets/nostalgia/69est090.html ). I imagine it might have been used--along with an Electro-Launch pad--by schools and clubs who liked to fly a lot of clustered models, or (by itself, with a Tilt-A-Pad) by people who didn't need or want to drive to a flying site; it provided a portable if rather heavy "mobile launch" option.

[Doug Sams]

http://www.ninfinger.org/rockets/nostalgia/69est086.html I can't begin to count the number of times I've thumbed thru those catalog pages and spotted that on the upper left. Yet despite those many looks, I don't think I ever realized that was being sold as a supplemental or separate battery pack - I think, out the corner of my eye, I always saw it as being a replacement base for an Electro-Launch system.

Thanks for posting that :)

Doug

.

[blackshire]

I can't begin to count the number of times I've thumbed thru those catalog pages and spotted that on the upper left. Yet despite those many looks, I don't think I ever realized that was being sold as a supplemental or separate battery pack - I think, out the corner of my eye, I always saw it as being a replacement base for an Electro-Launch system.

Thanks for posting that :)

Doug

.You're welcome. Never having had either an Electro-Launch pad or the battery pack, for many years I made the *opposite* error--I'd thought that the battery pack was some different item (maybe a battery holder case made for some other purpose) that Estes had bought and included in their catalogs, like the other electrical parts that they used to sell.

[luke strawwalker]

If one likes fiddlin' with clusters as I do, then a good 12V system is a must.

Doug

.

Like! OL J R :)