Saturday, February 14, 2009

Laptop DC plug protection hack: Safety on the cheap!

Faithful readers of the GSD blog may remember the near-disaster we went through here with our Gateway laptop:

Basically the plug socket jack solder-points became broken on the systemboard.

This turns to be a common problem for many laptops.

It was a $250 fix that I would rather not repeat.

Looking at the design and knowing how Alvis (and I) had been using it, I suspected the L-shaped design of the plug allowed it to swing downward and then when carelessly set on a lap, the ottoman, a table, etc. this could put pressure on the systemboard jack solder points and cause them to break.  Take a look at what I mean below.


In most cases that plug wants to point directly down and makes a 90-degree connection into the laptop DC plug jack receptacle.  Any pressure on the plug cord housing is transmitted directly to the plug jack as it is not fortified tightly/directly to the laptop casing body like some other systems I’ve seen (Dell).

I saw a guide once where a guy had hacked together a “strain-relief” connection with an unused modem jack plug/socket, cable, and some rubber bands.  It was ugly but worked.

Unfortunately, the back of this model laptop only has the DC plug socket on one side and a VGA D-sub connection point on the other corner.


But wait….maybe I could make a low-profile “dummy cap” for it to which I can affix a clip of sorts to hook the AC cord wire into.  That should keep the L-shaped AC/DC plug aligned safely so it doesn’t get jammed when resting on the desk or my lap and maybe apply pressure again that could re-break the solder joints.

I ran this thought across the D-man’s desk but he was having a hard time following.

So last weekend I did the hack and took pictures so everyone can see the MacGyver jury-rigging job that I did.

So far field-deployment has been very positive in the results!

The Hack-Job

I dropped in at RadioShack and picked up a 15-Position HD Male Solder D-Sub Connector.  They actually had two models.  One with the pins inserted as shown above and one without the pins inserted.

I got the pins-in-place model as I was thinking that the pins would help keep the jack aligned and attached more firmly.  In hindsight I should have got the other one.

Once at home I got out the Dremel and drilled a vertical 90-degree hole in the portion of the connector just behind the "plate”.  The hole was just large enough for a small plastic zip-fastener to fit through.  I also ground-smooth the sharp edges created when I drilled out the hole to make sure the cord (or me) didn’t get cut by any burrs.

Once done I inspected the work.

The problem I saw was that when I drilled through it some of the pins were now very loose.  I removed these with needle-nose pliers.

Then I wondered if maybe while making the cut, some metal fragments might cause a “short” between pins, thus sending a false signal to the VGA system.  That probably wouldn’t be good.

So I ended up extracting them all to leave the connector “pin-less”.

I attached the connector on one end of the laptop.

I then plugged in the DC plug on one side.

I routed the cord horizontally across the back being sure to leave just a little bit of slack to keep tension off the jack itself.

Then I threaded the zip-tie through the hole and bound the cord snugly to the connector housing with it; trimming off the zip-tie excess when done.





It works great.

the L-shaped jack is now safely oriented to keep it from getting jammed when the laptop is on a flat surface.


I suppose I could use screws to more securely attach it to the laptop, but I decided against that. I do want it to “break-away” easily if the cord is tripped over or snagged.

I did lightly crimp the housing just a bit to allow a snugger fit on the VGA plug itself.

I probably should have mounted it securely in a vise when I did the drill-out to get a more accurate hole and placement, but it was close enough.

All said, it cost just under $5.00 to rig this preventative getup.

Not too bad and not too ugly.

It remains small enough to wrap the cord up without adding much bulk.

Small price to pay.


--Claus V.


Anonymous said...

Clever !

Anonymous said...

Or you coulda just bought a JerkStopper.

Anonymous said...

This method is way better and safer that port destroying Jerk Stopper.