A little help from my friends?

I want to know how to build - from scratch - a battery charger. Simple. No feed back circuits. From 110v AC to 12V DC 6 amps.

Yes, a stepdown transformer and a rectifier, but I need more specifics than that.

It is hard to ask the right questions when I know so little as well.
 
Carol is there a very specific reason why? I mean if you were embarking on building electronic ciruits for a hobby as i did before i went into the field then it would be like all of us and woodworking you dont really care about the economics you do it for the pleasure and fun.

But battery charges are so cheap today that i doubt you gonna do it for less and then you need to think about the extras and the type of technology of battery you wish to charge.

These devices have come a long way from being just a transformer with a rectifier as we have learnt over time how to look after a battery and the different battery technologies.

What do you wish to use it for. Battery type, ampere hour rating etc.

There are many issues involved. I dont want to rattle on here and cover them all it would depend on the battery technology and use.

My recommendation though would be to urge you to buy before you build unless this is a very specific requirement that you aint seen a charger off the shelf for.
 
The point is not to charge a battery. It will be used to fire a wood burner pen.

So no smart technology which is where battery chargers are today.

For continued wood burning, especially when branding, an ordinary wood burning pen is far too wimpy. This circuit is further tempered with a dimmer switch to control the "temperature" of the pen.

The Silicon Woodturners club has an article in their newsletter archives where a member did use a manual charger to make one of these.

The problem is manual chargers are very hard to find. NAPA does make one but it is $90.

I did find a circuit on-line but I don't know how to evaluate it.
 
The point is not to charge a battery. It will be used to fire a wood burner pen.

So no smart technology which is where battery chargers are today.

For continued wood burning, especially when branding, an ordinary wood burning pen is far too wimpy. This circuit is further tempered with a dimmer switch to control the "temperature" of the pen.

The Silicon Woodturners club has an article in their newsletter archives where a member did use a manual charger to make one of these.

The problem is manual chargers are very hard to find. NAPA does make one but it is $90.

I did find a circuit on-line but I don't know how to evaluate it.


Carol that circuit should work fine...however I'd probably start with a battery charger even one from harbor freight, or a used one from Ebay unless you already have a transformer..

Garry
Garry
 
Carol

A little more research shows that the diodes and capacitor are unneeded. All that is need is a high current low voltage source. It a resistive heating unit that could care less if its feed AC or DC. In actual use probably less than three volts at 2-6 amps. The battery powered soldering irons I used at work ran off of 3 volts....

Back in the 60's we made soldering guns in shop class buy stripping the secondary off a transformer and placing a one turn secondary made out of a strap. Then feeding a normal soldering gun tip. Or making our own tip out of about 5 inches of #12 wire..

So to go simple hoop your dimmer up to the input of a 6 volt (not critical) 4 amp or so transformer and the secondary to your burning pen/element..

For other ides look at "Foam Cutters" as they are basically the same thing. And there is a little more info floating around the net for these things..
Garry
Here is a "sketch of a circuit that would work...safety is up to you..!

http://members.fortunecity.co.uk/slmohr/IMAGES/Foam_Cutter_PS.gif
 

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Carol,a pistol grip solder gun is a small transformer similar to a battery charger IF YOU need a smaller wood-burner
 
Carol, here is a link to an article that Allen Neighbors wrote and emailed to me some time ago on making one from a charger. I've had everything to make it for over a year...thanks for reminding me!! Hope you can get yours going soon!

>>>>LINK<<<<
 
Carol

You may have found this
http://www.woodburning.com/aboutwoodburners.asp

A quote from that page..
"Today, most (if not all) of the newer generation woodburning systems use an electronic circuit to more evenly regulate power output. The circuitry is similar in operation to a lamp dimmer, except that a transformer (primary side) takes the place of the light bulb. The control circuit varies the level of AC voltage to the transformer. The secondary of the transformer is connected to the output jack of the burner, which is where the burning pen is plugged in. The burner transformer is unique in that most units only generate around 2 volts AC to the burning pen. But even though the voltage is low, the current to the pen can be as high as 20 or more Amperes! This high current is needed to heat the resistance alloy (most use Nickel-Chromium wire) of the burning tip."
 
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