Estes Launch Controller Mod

[bigone5500]

I am going to modify an Estes Electron Beam controller to accommodate cluster configurations.

I am going to use 16 ga. speaker wire and a 6 volt alkaline lantern battery (radio shack #23-560).

Before I start work on it I want to verify that the lantern battery will produce enough current to ignite up to 4 18mm motors using estes igniters.

Can anyone verify this?

Thanks.!!

 

[jj94]

I can't be much help since I haven't tested my self, but I would think it would work. It might take a second or two for the ignitors to fire though. I would try it myself and see what happens. That way, you'll be sure it works. Oh, BTW, I'd use a 9.6V NiCad battery pack instead. More juice, smaller size, less weight.

 

[Race58]

IMHO I would not use 6 volts but rather 12 volts if you going to fire clusters. Something like this from Hobbico https://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXL370&P=ML.
You can find cheaper ones on Ebay also. They are small and inexpensive.
You could also just use your car battery and not spend any money.

 

[bigone5500]

You could also just use your car battery and not spend any money.

The only thing about the car battery is I can't take it out of the car. I launch in a field owned by a friend and he has a wood fence up that prohibits entrance.

I feel I'll have to rethink the lantern battery thing...

 

[m85476585]

I use a 9.6V rechargeable pack for my launcher. I haven't flown anything bigger than two motors with it, but it works great.

 

[poke44]

also those electric kids cars that get old and not played with use small 12 volt batteries.... I got the battery out of my nieces barbie jeep but it was deader than a doornail and wouldnt charge, but it was way way old.

 

[Handeman]

Get a motorcycle/lawn mower/garden tractor battery. You can find them for $20 to $30, maybe cheaper if you find a sale. They will put out upwards of 70 amps so will lite 4 estes igniters at a time and do it all day. When they drain down, recharge instead of buying more like you would have to do with lantern batteries. They will also fire most of the MPR and HPR igniters you might want to use.

 

[Spaceman Spiff]

IMHO I would not use 6 volts but rather 12 volts if you going to fire clusters. Something like this from Hobbico https://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXL370&P=ML.
You can find cheaper ones on Ebay also. They are small and inexpensive.
You could also just use your car battery and not spend any money.

I use a 12V gel cell similar to this -- there are lots of brands of 7AH gel cells like this one. They put out plenty of current, and are small and relatively lightweight. You can launch rockets all day and not deplete one of these. Charges easily overnight.

 

[SCE to AUX]

You can get small 12V gelled electrolyte batteries at Home Depot or Lowes. Used for emergency lights and alarm panels. Much nicer than a motorcycle/tractor battery, because it won't spill acid all over the place if tipped over.

I use a 12V 12AH gel-cell in my launch box, and have fired up to 14 Estes igniters at once with it without problems.

 

[bigone5500]

...Used for emergency lights and alarm panels.

Oh you just rang a bell...we have emergency lights all over the plant where I work and I know the guy that changes them out well...hmmm...I think I just heard one of them go bad...rats...

 

[bigone5500]

One more thing...

Can the Estes Controller handle the extra current draw?

 

[SCE to AUX]

The switch contacts themselves should be OK, but the thin wire needs to go.

And if you upgrade to 12V, you need to replace the 6V light bulb with a 12V equivalent.

Personally, I would keep the stock Estes unit in the bottom of the range box as a backup, and just build a 12V controller from scratch. There isn't a whole heck of a lot involved in a simple launch controller, and that way you get exactly what YOU want, not a hacked up Estes unit.

 

[JoeLaunchman]

I've found that a 6V lantern battery is reliable only for clusters of 2, and then only when it's fresh. I agree with the suggestion of a 12V atv/lawn tractor/motorcycle battery for reliable clustering. Try to find a rechargeable one and get a trickle charger to replenish the juice before launches. Pep Boys has a good selection of these type batteries for under $50 and chargers. I also suggest you upgrade to a 12V bulb.

 

[bigone5500]

Glad you guys mentioned the bulb. I hadn't even thought of that part...duh...

I'll be using 16 ga wire (radio shack #278-1105). I have built a 12v controller before but I didnt' like lugging it around...too much wire.

I'm gonna take the lantern battery back to RS...maybe they will have a 12v 7.2 Ah battery in stock...

 

[NUBlackshirts]

Here's what I did...

I rewired my Estes controller using lamp cord. I also used a male Tamiya-type connector. Now I can use the rechargeable 9.6V Nikko battery packs with it. I have easily fired 3x18mm clusters with no problems. I think it could fire a 4x18mm cluster too.

 

[KDRaven]

Hey Bigone5500 how about this idea. why not build up a relay operated remote unit that will place the battery out at the pad and you can use the stock estes launcher to activate the relay unit and then you will not have to convert your controller to 16ga wire and the relay unit will have shorter wires for more current to the pad from the battery. Also you can place a jumper wire in where the batteries are and hook one end of the estes controller to the 12v battery and the other to the relay and you dont have to have batts in the controller but will have to change the bulb out.
Here is a simple ckt.
View attachment simple remote relay controler.JPG
I hope this idea helps you out some.

For the relay use a SPDT that way the cont check goes through the relay so it can be tested before hooking the igniter up to see if the relay is not stuck in the launch position. and also use a 30amp rated relay.

 

[luke strawalker]

I love my old Pola-Pulse and Electron Beam controllers... I rewired them with lamp cord soldered to the battery contacts inside the case, extending out to 12 v car battery clips, but now I have one of those portable car boost-starting boxes with a cigarette lighter clip on top and I think I'll remove the clips and solder on a cigarette lighter plug instead, for an easier time. One of them I may just solder some big ring terminals to so I can use the big booster clamps for more current for clusters though...

I also got SO sick and tired of the dinky bulbs losing contact... half the time I used to fiddle with cleaning the clips and all that just to find out I had a bad bulb or the thing lost contact inside the controller... I soldered an LED to a resistor and then soldered that in place of the bulb, and it works like a champ. Only thing is, if you're using clamps onto a lawnmower or car battery, you have to observe the polarity or the LED won't light, unless you use a 2-way LED that glows green one direction and red in reverse polarity, or make 2 LED's with resistors soldered to either both the longer or both the shorter legs (leg length shows the polarity on LED's) and then solder one in and solder the second one in 'backwards'. There is plenty of room in the standard bulb socket for 2 LED's. If you using a cigarette lighter plug or a Dean's connector or something like that, just figure out the polarity and make sure the LED lights before you solder it together. Works like a champ!

Good luck! OL JR

 

[bigone5500]

Hey Bigone5500 how about this idea. why not build up a relay operated remote unit that will place the battery out at the pad and you can use the stock estes launcher to activate the relay unit and then you will not have to convert your controller to 16ga wire and the relay unit will have shorter wires for more current to the pad from the battery. Also you can place a jumper wire in where the batteries are and hook one end of the estes controller to the 12v battery and the other to the relay and you dont have to have batts in the controller but will have to change the bulb out.
Here is a simple ckt.
View attachment 50176
I hope this idea helps you out some.

For the relay use a SPDT that way the cont check goes through the relay so it can be tested before hooking the igniter up to see if the relay is not stuck in the launch position. and also use a 30amp rated relay.

I like this one. I have the stuff to make this work. I am wondering though...

How much resistance should there be in order to do a cont. check without setting off the igniter?

 

[Solomoriah]

30' of 16 AWG stranded copper wire should have a resistance around 0.12 ohms. Estes Electron Beam controllers normally have 15' of 18 AWG wire, which would have about 0.10 ohms of resistance. So 16 AWG wire ought to be okay for this purpose.

I also recommend the 12V gel batteries used for emergency lights... they are sealed and can handle a heavy current draw. I'm told that a standard 1 amp or lower AC adapter (wall wart) with the end cut off and fitted with battery clips can be used as a charger for this sort of battery; I have such an adapter but have not yet converted it. (Mine came fully charged out of a UPS system, discarded because it is too small for the new computer, and I haven't had launching weather yet to run it down.)

I'm planning to build a non-relay four-position launch controller, just as soon as I find a source for the diodes it requires...

https://rocketry.newcenturycomputers.net/launchcontroller.html

 

[SCE to AUX]

How much resistance should there be in order to do a cont. check without setting off the igniter?

Enough to limit the current to well below the "no-fire" current of the igniter being used. IIRC, the stock Estes lightbulb limits the current to ~150 mA @ 6V. This amount of current is more than enough to fire a flashbulb type igniter and some types of homemade e-matches, however.

Using an LED/resistor or piezo electronic beeper for a continuity indicator gets your test current down into the ~10 mA range, safe for any type of igniter in use.

 

[m85476585]

If you use one of these, it will limit the current to 15mA:
https://www.radioshack.com/product/index.jsp?parentPage=search&summary=summary&cp=&productId=2062568

If you add a buzzer like this:
https://www.radioshack.com/product/...r=1&origkw=buzzer&kw=buzzer&parentPage=search
in addition to the LED (in parallel), the total current will be 30mA.

 

[Solomoriah]

Um... I don't think so. The part you link to is just an LED. You must have a resistor in series with the LED to limit the current... the LED itself won't (well, after it burns out, current will be reduced to 0, but I don't think that's exactly the point).

You CAN get "flashlight" or "dash" type bulbs that contain both the LED and resistor. I haven't found them locally, but a friend who works in an industrial facility buys them by the box to replace ordinary bulbs in the equipment he services.

But the Radio Shack part shown isn't such a device, so far as I can tell. It's just an LED.

 

[KDRaven]

I have not figured out the current that the cont check of the controllers that I have built but I have had no igniter light while doing a cont check. In the 8 pad controller, I use a 1K 0hm resistor in series with the LED and also have a Peizo buzzer/diode combo in parallel with the LED/resistors.
In the remote relay controller I use a peiso buzzer/LED/1Kohm resistor in the cont check. The LEDs are a hi-intensity type for being able to see them in full daylight with no shadding.
I have used gelcell 12v batterys and also 900cca auto battery for the 8 controller and a lawn mower batt. for the relay unit.

 

[shreadvector]

If the lantern battery came from Radio Shack, you can return it and take the cash and buy 2 Alkaline Lantern batteries from Wal-Mart and wire them in parallel. Then you will have 6 volts, not need to change the lamp (aka "bulb"), and get double the current to the igniters.

FYI: lantern batteries (depending on the brand - and you can tell by weight) have either 4 D cells inside or 4 F cells which are like longer D cells and produce even more current at the same voltage.

https://data.energizer.com/PDFs/529.pdf

contains "Cells: Four 3-361 in series" and those are:

https://data.energizer.com/PDFs/3-361.pdf

Cool stuff on the web.....

 

[Micromeister]

Glad you guys mentioned the bulb. I hadn't even thought of that part...duh...

I'll be using 16 ga wire (radio shack #278-1105). I have built a 12v controller before but I didnt' like lugging it around...too much wire.

I'm gonna take the lantern battery back to RS...maybe they will have a 12v 7.2 Ah battery in stock...

Generally RS won't have the gel-cells in stock, but you can go to just about any hobby shop that sell to the RC community and pick up a Hobbico 12v 7Ah battery for somewhere between 17.00 to 20 bucks. they are perfect for personal launch systems and small cluster launching. Making an inexpensive charger is almost a no-brainer as well
16ga 2 conductor stranded copper "Lamp Cord" is also perfect of your use. Try to get White outer jacket as it's far easier to see on the ground the brown, making it less of a trip hazard works just great on the 50foot control circuit for my HD relay/solar launcher, packs well also.

 

[Race58]

Like I said earlier.


Something like this from Hobbico https://www3.towerhobbies.com/cgi-bin...&I=LXL370&P=ML.
You can find cheaper ones on Ebay also. They are small and inexpensive.


The Ebay listing for $6.50 + 12.95 shipping is right here: https://cgi.ebay.com/12V-7AH-12-Vol...ryZ40975QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Generally RS won't have the gel-cells in stock, but you can go to just about any hobby shop that sell to the RC community and pick up a Hobbico 12v 7Ah battery for somewhere between 17.00 to 20 bucks. they are perfect for personal launch systems and small cluster launching. Making an inexpensive charger is almost a no-brainer as well
16ga 2 conductor stranded copper "Lamp Cord" is also perfect of your use. Try to get White outer jacket as it's far easier to see on the ground the brown, making it less of a trip hazard works just great on the 50foot control circuit for my HD relay/solar launcher, packs well also.

 

[Solomoriah]

16ga 2 conductor stranded copper "Lamp Cord" is also perfect of your use. Try to get White outer jacket as it's far easier to see on the ground the brown, making it less of a trip hazard works just great on the 50foot control circuit for my HD relay/solar launcher, packs well also.

I need five 16ga or larger wires for my 4 way controller. I'll probably be zip tying three lamp cords together...

 

[m85476585]

Um... I don't think so. The part you link to is just an LED. You must have a resistor in series with the LED to limit the current... the LED itself won't (well, after it burns out, current will be reduced to 0, but I don't think that's exactly the point).

You CAN get "flashlight" or "dash" type bulbs that contain both the LED and resistor. I haven't found them locally, but a friend who works in an industrial facility buys them by the box to replace ordinary bulbs in the equipment he services.

But the Radio Shack part shown isn't such a device, so far as I can tell. It's just an LED.

It's a 12V LED, which basically means it is a regular LED with a built-in resistor (although it doesn't say it has a resistor, I assume it does because if will work off up to 16V, and a 4V increase over the typical voltage would kill any LED without a resistor).

 

[KDRaven]

Solomoriah, I just finished a build of a 2 pad relay controler and I have it posted under this thread https://www.rocketryforum.com/showthread.php?t=44015 and it can be added to for two more pads and the 2 pad design uses a 4pr cat5 wire for connection and to add more pads just add more relay ckts and another cat5 cable or a larger pr count cable. and for the drawing of the mods that I had made to your 4 pad launcher here it is
View attachment finalfourwaycontroller a.PNG
and as far as the 5 16 ga wires you can use 3 wire ext cords and get two pads per cord by using the white for one pad, black for second pad and green as return pad or or 2 ext cords and w=1 b=2 g=3 of one w=4 b=+ and g=- on the second cord and they come in 16ga also just some thoughts.

I also had made up a 8 pad launcher and it ultlises the ext cord idea for the conectivity of the pads and part of it is under the thread that I mentioned. the last 4 pads are shown because they are the ones that I modified for the new 2 pad relay unit. But the rest of the ckt is shown.

 

[Solomoriah]

Well, I'm sticking with my controller plan. I just placed an order for the switches, diodes, LEDs, and resistors, as well as a really sweet 20mm Big Red Button... all I have to handmake is the safety key socket (I've made three already, so no big deal).