.049 glow plug ?

Cox glow heads are rated for 1.5 volts. Use a high capacity 1.5v battery or battery box.

Back when I first started running engines, I used ones of these.



It lasted a long time, a real long time. Besides being expired for several years before I started using it, I used it for about 2 years until it wouldn't light a head bright enough. After that, I kicked it around my basement until it fell off the counter and the top blew off it a few years ago. I still have the battery sitting out in the garage, its empty now. I have thought about gutting it and installing some D cells in it to use for show. I currently use a Cox battery box with 2 D cells. I did experiment around with different batteries over the last few years. You can go out and buy a cheap 6 volt lantern battery, break the top off, remove all the "F" cells and rewire them in parallel. There you have a 1.5v "hobby battery".

I did try using rechargeable D batteries but they are 1.2V the glow plugs look like they lit very dimly?

so I set them up to 1.2V + 1.2V total 2.4V 2 D sized rechargeable and it glowed nice and bright.

looks like if I set them up to 1.2V it makes the plugs glow so dim it would be very hard to get the cars started.

Maybe I can put a reversed diode or two in line with the batteries and drop the voltage down.

reptile:

May be yes. Why not just use two 1 1/2 volt D cells in paralell (NOT series)?

Make things easy for yourself.

SD

SuperDave wrote:reptile:

May be yes.  Why not just use two 1 1/2 volt D cells in paralell (NOT series)?

Make things easy for yourself.

SD

Figured I can use my rechargables so I don't have to buy D batteries all the time.


I added a diode and brought down the voltage now it looks ok.

reptile:

I can get 2-3 flying  seasons out of a pair of Dura-Cel  D cells.  I buy them by the sleeve at COSTCO for my flashlights too.

I have several Mag-Lite 3 D cell flashlights that I call my "attitude adjustment tools".

     

SD

SuperDave wrote:reptile:

I can get 2-3 flying  seasons out of a pair of Dura-Cel  D cells.  I buy them by the sleeve at COSTCO for my flashlights too.

I have several Mag-Lite 3 D cell flashlights that I call my "attitude adjustment tools".

         

SD

Yes but at least I know if I am going to run some stuff I can charge batteries up before hand and they will be in tip top performance ready to GLOW! 

SuperDave wrote:reptile:
I can get 2-3 flying  seasons out of a pair of Dura-Cel  D cells.  I buy them by the sleeve at COSTCO for my flashlights too...

SD

How long the battery lasts depends on how fast you can start your engines.

...I see your start quickly. :-)

George

Yes George they do. Then I don't start them that often. Also I use Dura-Cel "Copper-Tops" with tend to recover better from loads placed upon them than the "el cheapo's".

SD

SuperDave wrote:Yes George they do.  Then I don't start them that often.  Also I use Dura-Cel "Copper-Tops" with tend to recover better from loads placed upon them than the "el cheapo's".

SD

Yes but rechargeable battery's can flow much higher amp rates through them and they last much longer.

reptile wrote:Maybe I can put a reversed diode or two in line with the batteries and drop the voltage down.

What's a diode going to do for you in a DC circuit?  I think you meant a resistor  

reptile wrote:I added a diode and brought down the voltage now it looks ok.

Unless you added a zenner diode. I still think you meant a resistor.

I think that a normal Diode does a drop voltage for 0.6 (0.7) Volt, so it's a simple way to reduce the voltage for the glow plug.

(I found some additionnal informations here : http://electronicsclub.info/diodes.htm

dinsdale wrote:

reptile wrote:Maybe I can put a reversed diode or two in line with the batteries and drop the voltage down.

What's a diode going to do for you in a DC circuit?  I think you meant a resistor  

Adding a diode (although forward biased rather than reversed) to a low voltage DC circuit is a fairly common means of dropping voltage by a fixed amount.  The drop is fairly stable and will vary little with current changes (variation is more of a factor of temperature).  Diode selection is important in order to ensure that it can carry the current demands of the load.  Although most data sheets list peak non-repetitive surge currents (many times quite high and occurring infrequently), these are of short duration because diodes are often employed in sinusoidal circuits and may cycle hundreds of thousands of times a second.  For heating plugs, the current load is constant so the diode must be up to the task.

Yep using diodes I also ran multiple ones side by side so they can take the power of when the glow plug shorts across the leads I used it the other day it works like a charm and what I really like about it is the diodes get warm when using it so if you feel the diodes and they are cold that means your glow plug went bad so this is also a plus in using rechargables with diodes.

Hmmmm. Outstanding. I've learned something new today. Many thanx for the explanation.

I made a battery tray with (2) D-size batteries that I can switch from 1.5V to 3V for those stubborn engines I normally use it as a 3V on everything though, I've only burned out 2 glow heads this past year.

Usually it's more current that keeps the plugs glowing red not more voltage. I have seen on most flight boxes you can adjust the current only. I could be wrong, just curious.

Ron

Cribbs74 wrote:Usually it's more current that keeps the plugs glowing red not more voltage. I have seen on most flight boxes you can adjust the current only. I could be wrong, just curious.
Ron

For my battery, I wired four single D cell holders in parallel. I use just two for the 1/2A, but I can use four if I'm going to use it for a larger glow like a .40 engine. I made bullet connectors on the battery holder so I can swap between a 1/2A glow plug clip and a clip for the standard glow plug.

The Versatile Mark

I made this battery box a while ago, works perfect:

https://www.coxengineforum.com/t4864-home-made-battery-box?highlight=battery

Lieven