Glow Sticks

[Steve Hargreaves - Moderator]

Still a big fan of 2V SLA cells for glow plug duties....

This is what currently lurks in the bottom of my toolbox....though I think the 5Ah version is a better bet....

[Former Member]

[This posting has been removed]

[Peter Christy]

Merco 61: Its not just about voltage, but also the internal resistance of the cell - ie: the maximum current a cell can provide. This needs to be significantly more than the plug draws.

Trust me - a single C or D NiMh cell will light either 1.5v or 2V more than adequately. The plug should glow cherry red, not bright orange!

Running on a single C or D NiMh will guarantee that the plug will never be over driven, and they will last a very long time when used this way!

--

Pete

[extra slim]

I use one of these with a 3s lipo.. variable, lipo, swapped crocs for connectors, relatively cheap.. really no complaints

 

**LINK**

Edited By extra slim on 29/11/2018 14:10:24

[robert chamberlain]

as I understand it, power panels are powered by a 12 V battery which drop it down to something that can be used to light a glow plug. If I were to make up a cable that was connected to my 12V sealed battery and run it to my glow plug,-----what size/type resister would I wire into one lead of said cable to drop the voltage????

[Don Fry]

Power panels put 12 volts onto the plug, but in very short switched bursts. I.e. A high speed on off switch.

If you do try a resister, Ohms law goes, volts = resistance * amps, so as plugs need between 2 and three amps to get them cherry red, you will need between 4 and 6 ohms.

That, watts = volts *amps, suggests your resististance needs to handle 36 watts.

A bit of restistance wire from a room heater would do, but it's all a bit Heath Robinson, and burnt fingers.

[Nigel R]

"If I were to make up a cable that was connected to my 12V sealed battery and run it to my glow plug"

Really, don't bother, you'd want a physically massive resistor to cope which would end up rushing you as much as a better solution.

This is already a well solved problem, sub C in a glow stick.

Or use the fastttrax drive linked by extra slim.

Or a power panel £15 here or a mini version £7 here.

[Peter Christy]

My personal opinion, but I do NOT like power panels in any shape or form! I'm a great believer in keeping things as simple as possible, and by far the simplest solution is a single C or D cell. Putting an ammeter in series will provide useful information.

Power panels make it far too easy to crank up the current to clear a flooded plug. The problem then is that as the fuel boils off, there is a real danger of over-driving the plug - however briefly - which will shorten its life!

The plugs in some of my engines have been in there for years, still giving good service. I only ever use a single C or D cell to drive them.

--

Pete

[Denis Watkins]

Posted by Nigel R on 27/11/2018 16:44:44:

I am not a control line flyer. But I do remember reading the article that was published along with the DIY glow driver schematic in question. I did think about doing one for a project at home. But I'd need a PCB etched and I don't have facility for it.

Apologies for this delay Nigel, but I have some input.

PCB etching is within our scope Barring one obstacle, the Ferric Chloride.

This etches away the copper, and is nasty nasty stuff to have around, and really you should not even flush it down the drain, as it eats through most things.

VeroBoard, is copper clad, predrilled, prototyping Board, and will serve your purpose.

It is fairly simple to reschedule your schematic diagram to your board as

A Schematic Diagram has a top, bottom and middle

And so does VeroBoard, so just place your components tidyley within the tracks

[SR 71]

Im in the process of building 4 onboard glow drivers fo my 134"TN Lancaster, but having a little trouble with it, i can only get 2v batteries in the 1600 size and with the wiring involved im wondering if they are big enough to o the job

I have one on each engine

[Nigel R]

Thanks Denis, many moons ago I have used ferric chloride, but not something I wanted to get involved in again. The PCB in question, I did make a start translating to stripboard but it started getting complex and large. I might dig the project out again one day and sort a vero layout.

[Martin Harris - Moderator]

Posted by Denis Watkins on 04/12/2018 11:53:30:

PCB etching is within our scope Barring one obstacle, the Ferric Chloride.

This etches away the copper, and is nasty nasty stuff to have around, and really you should not even flush it down the drain, as it eats through most things.

It might not be the end of the world:

When dissolved in water, iron(III) chloride undergoes hydrolysis and gives off heat in an exothermic reaction. The resulting brown, acidic, and corrosive solution is used as a flocculant in sewage treatment and drinking water production,

Somewhere in my loft is a bottle of Ferric Chloride bought in the late 70s/early 80s and last used the best part of 20 years ago - one day I'll probably have to decide how to dispose of it!

[Tim Flyer]

This thread inspired me to build a twin NIMH D Cell glow box . The left hand pair of terminals are linked to the ammeter to check plugs etc in use. The right terminals are for charging but can be used along with left hand ones for twin cylinder engines. I like glow sticks but they are not very good on some of my models where s lighter and more nimble glow lead is easier and safer to remove from a running engine. Here are pics.

Edited By Tim Flyer on 12/12/2018 22:47:08

[Tim Flyer]

The total cost of ammeter and batteries etc was about £10.00 in all

[Peter Christy]

Nice work, but just be wary of wiring NiMhs in parallel. Unlike LiPos, they are not self regulating, and any mismatch in the cells can make the "good" one pull the "bad" one down.

Should be OK when new, but keep an eye on them as they get older.

--

Pete

[Ron Gray]

Nice, neat and tidy work Tim.

[Tim Flyer]

Cheers Peter I will check that . With 3000mah each they should have enough power even for twins ( I haven’t got one yet) . If I need to cycle the batteries the lid comes off easily with the four Allen bolts. The batteries are held in with springs and not soldered together so are easily removed /replaced . The contacts are also easily removed/replaced. The central section pulls out too so any maintenance should be easy. It was inspired by a Dualit Toaster 😉. I’m going to paint it with epoxy next so oil smothering won’t affect it . It’s all made with scrap wood and as said cost me a tenner all in 😊

[Tim Flyer]

Cheers Ron . I spent a few nights on it.... it still looks a bit “retro old school DIY” and the wood is just cheap scrap but to be honest it was a bit of fun tinkering 😊

[Graeme Poke]

As suggested by Steve Hargreaves back in November, I have bought a Cyclon 2v 5ah SLA battery. I have a smart charger. At what rate should I charge it please? Also I am concerned it will put out more that 2v fully charged resulting in blown glow plugs. Should I restrict it somehow? My knowledge of electrics is abysmal . Any help much appreciated.

Cheers Graeme

[Denis Watkins]

Lead acid and gel and nimhs cells don't like being overheated Graeme

So we charge at 1/10 Capacity usually

But in a rush to get out, occasionally 1C

In your case 1C is 5000ma, so charge at 1/10th that at 500ma for 10 hours for a flat discharged cell

Edited By Denis Watkins on 11/05/2019 08:14:31

[Former Member]

[This posting has been removed]

[Steve Hargreaves - Moderator]

SLAs usually charge using the Constant Current/Constant Voltage regime.....this means they will charge at a set current until a specific voltage is reached & then that voltage will be held & the current reduced until the battery is fully charged. For a single SLA cell the max voltage is about 2.3 volts.

Your smart charger should take care of all this for you though Graeme....tell the charger its a single cell (might be 1S on your menu) set the current to....well Denis' 500mA is as good as anything but you can go higher if you like....anything up to 1A will be fine.

Press start & the current & voltage should start to tick upwards until either the current hits 500mA or the voltage rises to 2.3V......the battery will start to charge. When it's fully charged the charger will switch off....

As Doc says a fully charged cell can be as high as 2.2V straight from the charger but this will soon drop back....make sure you charge the cell a few days before you go flying & it will be fine.... If you are concerned that the voltage is too high a long glow lead (1-1.5m) will drop the voltage sufficiently but personally I don't bother. If you DO go for a long lead make sure it can't tangle with the prop when in use.....that can really spoil your day...

[Graeme Poke]

Thank you Dennis. The shop advised me at 1 amp. I will back off that as you advise.

Gee Doc. So much stuff out there of which I wasn't aware. I am embarrassed to start it up again.

Well thats me sorted Steve. I have 3 smart chargers. 2 Swallows and 1 SkyrcD100. I'm assuming I use the PB setting.

The Swallows details are, C= (say) 0.5a, 2v pack. No mention of cells.

The SKYRC has (say) 0.5a. 2v (1p) No mention of cells.

So in both cases I presume those settings will be ok, with maybe a variance of the ma up to 1000ma.

I have charged the battery on both types of chargers. The SKY finished at 2.4v, the swallow at 2.34.

I have a 1.5m cable and the plug is certainly much brighter than my glow sticks. So all good so far.

I guess I needn't charge every time I fly. just check the brightness of the glow occasionally.

Thank you all for your much needed help. Graeme

[Geoff S]

I used to use 3x 2.5AH Cyclon cells in series fitted in a drinking bottle to supply the lights on my bike for my cycle commute before I retired. I used to recharge them at work with a standard bench power supply at a constant voltage of 7.5v (I used to 'acquire' a power supply for each winter - the benefits of working in an electronics lab . I think a constant current is also OK so you could use a LiPo setting.

Full Cyclon data, including the charge regime is available here.

Geoff

[Paul Marsh]

I don't use lead glow clips as they can get caught in the plug and not ideal for quick starts at a show or fly in. Carry around 6 at a fly in, but rotate them, however use the Lipo one which last a long time.