Step 3:

Now, solder 2 wires to both contacts. Be sure the wires are long enough to reach the bottom part of the battery where you will solder them to the 1/4th inch female jack.

Drill a hole in the bottom of the battery to fit the 1/4th inch jack.

Insert the 1/4th inch jack then solder the two wires to each lead. Make note of the polarity (+ / - ).

I used hot glue to fasten it in.

Put the contacts back into the tip of the battery and re-assemble your battery.
<p>This doesn't quite work. I had the same idea. The problem is that a laptop AC adapter can't supply the full current at the pace/amount the device motor wants. You can run the device motor, but the power and torque are feeble. I used a cordless drill and I could stop a drill chuck easily by hand.<br><br>Back before the batteries died, if they were charged up - they were able to supply all the juice the drill wanted. Torque was high, speed was quick. Full pull on the variable speed trigger was almost like firing a gun - Boom! Hole drilled! The torque was high enough that I could scarcely stop the drill chuck by grabbing it.<br><br>My old drill is an 18v. Inside the battery pack were 15 x 1.2v NiCad 2.2 Ah cells. <br><br>I found an old laptop and it's AC adapter. The adapter was rated for 18.5v and 3.5A. It seemed adequately rated for this battery pack hack. Not so. The drill motor actually draws more current at higher speeds/loads. The series of NiCads in the battery pack could supply that current quickly. The AC adapter cannot. At least, not the AC adapter I have. <br><br>I put a multimeter set for 10A current range on the hacked AC adapter circuit. I pulled the trigger on the drill and the current topped out slightly over the AC adapter's limit ~ 3.69A.<br><br>I quickly realized I could have blown out the fuse on the meter if I was testing with a higher power AC adapter or a good battery pack.<br><br>The bottom line is that good NiCads easily supply upwards of 20A at high speed or under load. A laptop AC adapter doesn't even come close to supplying that.<br><br>Take a look at <a href="https://www.youtube.com/watch?v=9Zt3P9bvn8M" rel="nofollow">this video where the guy is demonstrating current reading</a> using a 20A rated multimeter and a cordless drill. <br><br>My guess is that, in addition to not being able to supply the current the drill motor wants, the AC adapter is not designed to supply current quickly, or conversely, it is designed to prevent quick current draw.</p>
<p>Very nice. I had a printer power supply that wasnt steady. It sent power at about one second intervals. I like the connector. Super convenient to not always be tangling up wires. If you were using that circular saw powered by a battery and it lasted 15 minutes that is amazing. My dad has a set of porter cable power tools-drills, sawzaw, circular saw. The drill and the sawzaw you can use for a long time off battery. the circular saw is basically unusable.Not even juice. I dont know if it's even meant for wood. It might be for intended to use for scrapbooking or something.</p>
I think this is a great and simple solution to a common problem. For some reason though, i am always afraid of using audio connectors for power-related projects, mainly for the reason that someone might use it for audio and end up frying their equipment. My fear is completely unfounded but for some reason its still there. Aside from that, do you find that the 1/4" jack stays put?
I'd be reluctant to use a TS (tip-sleeve) connector for another reason: one contact slides past the other when it's connected or disconnected, possibly resulting in sparks or a short circuit.
I have one of those jacks in use as a lamp swivel power jack(12V, 1/3A led homebrew light bulb).<br/>holds just fine. &quot;minimal specs&quot; for commercial version of the jack is 1lbs. of extraction force. can be as high as 7lbs.<br/><br/>just fyi, specced at .05 ohm resistance after weathering and ambient humidity.<br/><br/>here's the important part.<br/>Contact rating is 1 A, 25 V DC<br/><br/>So, &quot;the salvaged epson printer power supply rated 24v, 2A&quot; is 100% OVER spec. now, if that was a <em><strong>12 Volt</strong></em> 1A power supply/drill you'd be &quot;safe&quot;.<br/><br/>Staying below that spec should also allow relatively safe &quot;mistakes&quot; since the audio equipment should be either fused, or just plain designed to handle that current without risk of frying you.<br/>
Well,thinking some amps are near 1kW per channel...
You can always take a label maker to the jack and mark it as "POWER IN"
I like the plug idea, it makes for a clean disconnect. I was considering something like this before I figured out how to repair my battery charger (in my case, the batteries weren't the problem). <br><br>My main concern with the direct connection was the balance - have you considered filling the empty battery case with inert weight to make the tool still feel balanced?
I would like to try this but I'm curious. 18V at 2 amps seems like it would be underpowered; don't ~5&quot; circular saws usually draw 6-7 amps on 120V ac?<br />
so does the Epson printer cable output DC power? My 16V-32V (three hole) cable is not either cutting off (at 16v) or pulsing/ticking when I turn on my Powermate saw. Not sure what I missed. So essentially, you just connected negative to - and positive to +, no ac to dc converter right?<br />
You should probably use another AC to DC adapter. 32 volts is too much for the saw.<br /> Not all Epson power supplies are the same.&nbsp; <br /> <br /> Find an adapter with just ONE voltage listed on the bottom sticker (18v or 19v or 20v or 21v or 22v or 23v or 24v and at least 2A)&nbsp; <br /> <br /> post a pic if you get one and you're unsure<br /> <br />
it will not fry iether saw or power supply if im running the saw for 15minutes? i want to try dis but i'm worried running 24v dc to 18v motor of my saw&nbsp; will be damage.<br />
mine still works...<br />
if doing this mod to a drill, i would recommend mounting the plug in the side of the former battery.<br />
this is a great idea<sub>, good work</sub><br/>
If the audio jack is much of a problem, keep it away from small kids and be sure to mention that it's a power jack before you lend it out. Basic precautions ;) I just happened to have one around and i think it looks quite nice compared to other connectors.

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