Introduction: How to Make a Cordless Tool Corded

Picture of How to Make a Cordless Tool Corded
First, your burning question: why would anyone want to do this?!
Well, for me there were a couple of reasons:
1. Dead batteries suck! And, when you're running a circular saw, saw-zall, or pretty much anything else constantly, dead batteries happen very frequently.
2. Batteries are not cheap, and they don't charge fast. Even with 5 batteries and 3 chargers, a good-sized project + my questionable competence at most things one can do with power tools often leads to waiting for dead batteries to recharge.
3. More power:) You've overclocked your computer, so why not overclock your power tools?
4. I *think* this'll be a bit more energy-efficient than recharging and discharging batteries... certainly more earth-friendly if you take into account impact of metal used in extra batteries you won't have to buy...

As usual, this is not the safest or most professional of projects. Please don't hurt yourself any more than you'd like to:-)

Here's a video:

Step 1: Gather Your Supplies

Picture of Gather Your Supplies

You'll need:
-cordless tool(s) to make work corded, complete with charger. I used these.
-an old ac power cord that you don't mind ruining
-an extension cord to run between charger and tool
-foam or something else that's nonconductive, flexible, and easy to work with. i used a dried-out piece of the nastiness that is known as great stuff.
-your favorite roll of duct tape
-aluminum foil or other conductive, flexible material

And, it'd make life easier to have:
-something to make the corded adaptor easy to remove from the tool. I used these, and they worked well.
-wire strippers
-pocket knife, leatherman, or other way of cutting and turning screws
-a pack of spare batteries, like these.

I'm sure you can do this with other tools; I happened to have a set of the cheap-but-usable Ryobi stuff, so that's what I went with.

Step 2: Modify (or Build) the Battery Connector

Picture of Modify (or Build) the Battery Connector

If your tool set has a carrying accessory that snaps into the battery connector like mine did, this step's easy: just cut a hole through the carrying accessory that's slightly bigger than the cord you want to run through here. If this doesn't exist for your tool, create one out of your favorite nonconductive substance or (carefully) take apart a battery and just use the shell.

I got annoyed by the nylon carrying loop thing, so I cut that off too.

Step 3: Attach the Cord

Picture of Attach the Cord

Next, you'll need to run the end of your AC cord through the hole you just cut in the accessory connector:
1. Push, pull and otherwise force the wire through, with the AC prongs facing the bottom (you'll connect these to the extension cord when you want to run power to the tool). Needlenose pliers were helpful for me on this step.
2. Attach thin strips of duct tape around the cord, right by where the cord enters the accessory connector.
3. Strip the ends of the extension cord's wire.

Step 4: Carve the Connecting Thingie

Picture of Carve the Connecting Thingie

The tool's leads to connect to the battery are not at the base of the battery connector: they're on the sides, near the top. So, you need something to get your wires up into the tool and touching the tool's battery leads.

I used a dried chunk of Great Stuff, the spray foam that is a pain to remove from pretty much any surface:
1. carve foam chunk such that, when it rests on the accessory connector, it's approximately the same size as the battery pack's lead
2. carve an 'arch' through which the 2 wires can lead to the terminals
3. if the carved foam is too tall, drim down to approximately same height as battery pack
4. run one wire to each side of the arch
5. attach aluminum foil to each wire and wrap the whole thing in duct tape. be sure you leave foil exposed, so that the tools leads can contact the foil on both sides. if (when) the connector won't slide onto your tool, trim off all the extra duct tape you used:)

Step 5: Modify (or Build) the Charger

Picture of Modify (or Build) the Charger

You'll need something for the other end of the DC-carrying extension cord to attach to, and this something will be an AC outlet connected to the charger.

Easy way to do this: run some aluminum foil or a wire to the point of connection between battery leads and charger. On most modern chargers, you'll need to put a discharged battery in the charger before you can provide any current to the tool. I tried this, and my corded adaptor would stop working whenever the battery became fully charged.

The way I did this: connect to the battery charging terminals, but from inside the charger. This lets me use the charger to recharge a battery while also powering a tool via the corded adaptor, and I don't have anything interfering with the charger connection to the battery. I meaured >10 amps output when a battery was not inserted using this method, so be careful: hooking a tool up to this might turn it / the charger / you into a charred chunk

Yes, both of the aforementioned methods probably increase the likelihood of battery or tool explosions or other nastiness occurring.

Smartest way to do this: measure the current and voltage provided by your battery and create an ac-dc adaptor that'll output this.

Step 6: Rock And/or Roll, Without Recharging!

Picture of Rock And/or Roll, Without Recharging!

Check the voltage/amperage output with your multimeter to make sure it's within a range of the intended input to the tool for you to feel safe (note: for me this required keeping a batter recharging while using the corded adaptor. if the battery finishes recharging while i have this connected, that *might* be a problem...), connect an extension cord between dc-carrying ac outlet attached to charger, and plug the other end into your corded cordless adaptor. turn your newly-corded tool on, and rock and roll! if it doesn't work, i'd bet you w/ 10 to 1 odds that your aluminum foil attached to the carved connector thingie isn't making contact with the leads on the tool. Duct tape and foil away until you've got it right, and happy tooling:)


abadfart (author)2016-01-18

Just a thought for people that upgraded to li-po batteries, you could pull the tranformer out of the charger and put it in one of the old ni-cad batteries and use that

taylorlightfoot (author)2015-04-28

There are cordless power tools that charge quickly enough for one to not need 5 batteries. My Makita tools recharge in 30 minutes and I get by just fine using two batteries.

TomD8 (author)2015-01-03

how did dewalt get a 24 V 350 watt supply in that 24 v battery case? was their a brick on floor to run the dummy battery case ive a rigid max HC nimh battery its like 5x3x2.3 can i get a supply in it?

shakeq79 (author)2013-11-26

Maybe you'll need a voltmeter to figure out what each of the different leads are. I wouldn't use a larger voltage battery, you might get away with 12V without burning it out instantly, but you'll definitely shorten the life. Have you thought about re-celling the battery? Hollow out the battery more

legotech7 (author)2012-07-01

Here's my comment. Don't do this! Ever!!!!!!!!!!

seansarvela (author)2011-06-01

I watched the first five minutes of your video...figured I had the overall point . Made my own yea..don't plug this directly into the wall....after the smoke had cleared , I watched the rest of your video.

omgitzstegman (author)2010-07-08

Seriously, next time cannibalize an old battery or even get a ghetto cheap generic replacement to cannibalize.

I know it doesn't take long for those batteries to go bad in the first place. On another note, seriously, tin foil, great stuff and duct tape? Dude, you're going to wind up with the ultimate multi-tool: all-in-one flame thrower, arc welder, power saw.

Overall though, very awesome you rigged that up. I just hope you own a fire extinguisher ^_^

ottist35 (author)2010-02-25

 Talk about living on the edge...well at least he is trying stuff a lot of us have been wondering if it is possible. Thanks for the instructable man!

SSmithers (author)2009-08-30

I think he's cute, and if wants to do something dangerous shirtless without tatoos and paunch, I'll certainly watch. However, I hestitate to speculate on the pants situation....

scob89 (author)2009-06-16

First, Get a shirt. Second, just you wait til someone comes along to use your tool and they plug it into a real wall outlet. that will make your day. And you should really cover up those electrical connections and use a proper outlet box. I also agree with 12V and say, replace the batteries with higher capacity ones. Also, need better pictures, I think my ole camera would outdo that cellphone camera.

klee27x (author)2009-04-12

1) Use a thicker cable, btw. Those cords are meant to carry prolly no more than 4 amps. At 120AC, 4 amps is a lot. At 12V or w/e ur running, 4A is nothing. Oh, and throw away the tinfoil crap and start over. 2) Stick a battery in the charger while using your saw. Sure, we all say your saw running just peachy for 3/4 of a second under no load. But have you tried to actually cut anything, yet? I have a feeling your saw will stall and the motor and/or charger will go up in smoke. Peak current output of a NiMh battery is higher than what even a large power supply can provide. So make sure you keep a charged battery in the charger while you're doing this. The battery will be there to prevent a problem when the peak load exceeds the charger's output.

12V (author)klee27x2009-05-20

if you change the cells in the battery to 3800mah ni-mh sub-c cells it will last up to 4 times longer! battery voltage no.cells neded 7.2 6 9.6 8 12 10 14.4 12 18 15 24 20 30 25 why not change the old 1200s for 3000+? the table shows how many cells to buy to replace the 1200s

grodenbarg (author)2009-03-29

That looks dangerous, and you can fry your charger by overloading it with the saw. BTW: I converted my cordless drill in a more safer manner by gutting a dead battery pack, and wiring a car plug to it's terminals (lot more versatile for power supplies for any use).

billygetsthegoat (author)2009-03-28

this seems like a good idea and dewalt did have a 24volt version of this (minus the duct tape ,fire/death trap and just plain stupidity)but OH MY GOD WHAT THE HELL ARE YOU PLAYING AT YOU FOOL? duct tape? alu foil? is this a kids program making a space suit? you're not going to open that charger while it's still conected are you? OH YES YOUR ARE! why didn't you just use the top of one of the batteries?

tw34kfr34k (author)2009-03-14

keep in mind you probably arent insured if you mess with the power supply of tools @ work

jerry rigger (author)2009-03-02

wow that looks so safe!

Derin (author)2008-09-19

dude,get a shirt

cooblades (author)2008-04-04

There is a reason why cordless power tools are not manufactured for corded and cordless use. Cordless power tools and corded power tools use different types of motors. The reason they don't make a corded attachments for current cordless tools is because the transformers required must handle a lot of current and are very expensive, most times more expensive than buying an entirely new tool. Lets give an example, if you had cordless power tool a that was 12V, lets say it sank 2 amps... well then the tool would use 24 watts(V*I) of electrical power. Now lets say we design a different tool using a 120V ac motor and we want the same power, well now we only need (W/V) 0.2 amps. A lot less current, which means a lot less heat in the transformer. Now I can't say I design power tools but I have done a bit of research when trying to build my own version of this project in the past. A few safety recommendations. Don't use duct tape on electrical work, use electrical tape, its not expensive it is meant for that purpose. Duct tape isn't even used on ducts, so it gives you an impression to how reliable it really is. Don't use a wimpy 2 prong cord to handle 24 amps, they barely handle 2 amps without blowing up. Also add a fuse and a shirt. :-P

carpespasm (author)cooblades2008-08-02

Even with the bootleggery I do this setup scared me. I doubt the charger will last long if you use it for that purpose, as you said the wire is too small, and using wall sockets and plugs for the connectors is just begging to have the itch to plug it in the wall and blow up a decent drill get to strong or have someone who's not familiar with your setup do it for you. I've tried to make this sort of adapter though, using an old 12v drill and an arm full of 12v a/c adapters strung in parallel for higher amperage. It was unimpressive for practical use.

struckbyanarrow (author)2008-04-16

why r u half naked in your vid and pics.... r u a hobo?

Redgerr (author)struckbyanarrow2008-07-16

he is showing us his muscles!!! >:O kida strange though lol-- i would have worn a shirt or if i really wanted to show em off- a tank-top lol

ArnoldB (author)2008-05-23

For the love of Americas Squeamishness put on a shirt!

Me uh (author)2008-04-07

It's not a gimmick. I've seen this guy around, and he never wears a shirt, especially when there is the chance of developing a nasty battle scar during Instructable-creation. And with his safety guidelines, there is QUITE the chance.

0.775volts (author)2008-04-06

dude, he's taking tools apart with other tools, this requires manly bare-chestedness. I for one salute your non-shirt-wearing creationism.

Mr. Rig It (author)2008-04-04

How dare you modify the greatest tool set ever made! This is blasphemy! Ryobi tools are NOT to be modified (quickly pacing back and forth and breathing deeply). That's it I must flagg this ible for such disrespect to the greatest of all affordable tool makers. Oh and one more thing... Yeah uuuhhh.... what you had to have your shirt off when you made the video?

Lftndbt (author)Mr. Rig It2008-04-05

LoL, you sound like my friend at work. We are not allowed to carry the ryobi One+ system items. But we have managed to order in the, circ, planner, recip etc and hide them from management.

Not a bad system for the price. You need to buy the None one+ cordless drill and batt the start off, not marketed as one plus but functions with it, yet it is 60$AU cheaper than the branded one + starter kit with cordless drill. We managed to work that out so we could make initial purchase of batts cheaper.

Do you have much of the range? How has it preformed for you?

Mr. Rig It (author)Lftndbt2008-04-05

"None one+ cordless drill and batt" I am not sure I understand. Do you have a link to this one? "Do you have much of the range?" I don't know what you mean by this. I love my Ryobi tools I have the 18 + 1 system: circ saw, recip saw, drill, vac, light, leaf blower, sander, and speed saw. I would like to get the chain saw, jig saw, orbital sander, buffer, and hedge trimmer. What they need to make is a weed eater/ grass trimmer. I would buy the weed eater today if they had one. I may go buy the new lithium ion batteries and charger with in the next year. They are suppose to last twice as long, but my regular batteries work pretty well for now. They last longer than my 14.4 volt ryobi drill, which I am going to retire soon. I have had it for 7 years and the 14.4 volts battery service life seems to be short, or time just goes by so fast I don't notice. Anyway they have me sold on them.

Mr. Rig It (author)Mr. Rig It2008-04-05

I just got back from Home Depot and guess what I found on the shelf a Ryobi 18 + 1 weedeater! They don't even have them on the RYOBI page. $39.99 So I bought it, just like I said I would. It has given me the insperarion to go mow the grass and they try the new toy.

Lftndbt (author)Mr. Rig It2008-04-06

Ryobi 18 + 1 ??
In AU it is marketed as 18 one +

Probably hence the confusion.

You have answered my question though.
It's nice to see that you have really taken full advantage of the system with your expansive range. Nice work.

Kiteman (author)Mr. Rig It2008-04-05

I think he took this other Instructable too literally...

!Andrew_Modder! (author)2008-04-05

that looks deadly =\

GorillazMiko (author)2008-04-05

Could have better pictures, but nice idea.

LinuxH4x0r (author)2008-04-04

Dude, get a shirt. Another thing to do is make sure that your charger is powerful enough to run it without melting. Other than that, great idea

GorillazMiko (author)LinuxH4x0r2008-04-05

First sentence you typed = hilarious.

i make shooting things (author)2008-04-04

shirt please??

About This Instructable




Bio: bicycles, gardening, and other important stuff
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