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Graco Swing By Me - Battery to AC wall adapter modification

If you have one of these Graco battery powered swings you are probably familiar with the cost of C batteries! The swing takes four of them and they only last a handful of days. I'm not sure if the newer models support being plugged into the wall but ours didn't. If you are a little familiar with electronics and soldering, here is a rough guide on how you can modify yours to plug in!



I wasn't sure how exactly to disassemble the swing side where the batteries were. I was able to open up the clamshell a bit but throughout this mod I was unable to determine how to fully separate the pieces. I suspect that there is some kind of a slip plate on the moving arm portion. The two parts of the plastic are assembled and the moving arm portion with the slip plate is slid onto the shaft. Because of the tension in that slip plate it doesn't want to back away, and because of the mechanicals that portion of the assembly doesn't appear accessible in order to free it. I wasn't willing to break the swing to find out and as you can see below there is enough room to work by prying the plastic pieces apart a bit, but not too much!



The swing takes 4 C batteries. C batteries have a nominal voltage of 1.5V. Inspecting the battery compartment shows that the batteries alternate in the direction they are installed. This, and checking the voltages at both ends of the battery compartment with a multi-meter, confirmed that the batteries are wired in series. This is to provide a desired voltage for the motor powering the swing. Voltages in series are additive so:

1.5V/battery * 4 batteries = 6V

Batteries are also DC so we can be more specific and say that we need a AC-DC adapter that supplies 6V. Batteries are also quite good at supplying high levels of current so we want to get as high a power converter as is reasonably affordable.

The other part we need to select is the plug that will be mounted in the swing that the AC-DC adapter will plug into. The sizes of the plugs and adapters here is important. Barrel jack connectors have different diameters and depths, you have to select them to match.

Based on the 6V requirement I found this adapter, the DIKOO AC adapter, 6V 1A available from amazon for $8.

This adapter has a 5.5x2.5mm/5.5 x 2.1mm plug. Based on this I found female jacks that matched the specs of the adapter.

We have our adapter and jacks selected and both for under $15 dollars!

I selected the outside of the case to add the jack. This would keep the AC-DC adapter cable away from the moving portion of the swing. After finding a suitable spot that I could access but that wouldn't hit anything important during drilling I made a mark and drilled a hole just big enough to fit the adapter plug and mounted the plug.



The jack looks like it was meant to be there!


At this point there aren't too many additional pictures but here is what I did:

  • There are two wires that go to battery compartment terminals. One goes to a terminal where the positive end of a battery will contact and the other a negative. Identify which is which, this is important.
  • Soldered two wires to the terminals of the jack, long enough for both of them to reach the battery terminals or where the battery terminal wires were soldered.
  • I plugged the AC-DC adapter in and plugged it into the jack. Using a multi-meter I determined which wire was positive (+) and which was negative (-).
  • Unplugged the AC-DC adapter.
  • Then I soldered the corresponding wire from the jack to the battery terminal connections identified above with the matching polarity. I can't recall exactly where I made these connections but I did use existing solder points and I did not disconnect any wires from the battery terminals, just in case someone wanted to use batteries in the future.
  • At this point I made sure the plastic fit back together properly and powered it up to try it out. Note that you can either use batteries or the AC-DC adapter but not both, that would be bad!

Here you can see the reassembled swing and the adapter plugged into the side. We ended up using this with our daughter for a number of months without any problems, and without having to change batteries!


After this modification it was apparent that the plugged in version had more energy than the battery version. Full speed was like an amusement ride. We could have potentially gotten a 5V adapter instead, 1.2V * 4 batteries = 4.8V, but we just adjusted the speed to be reasonable instead.

I work with electronics pretty regularly and this mod took me about a half hour to complete (after I had the adapter the jacks). The parts were relatively low cost, under $15 dollars. We probably didn't save more than the parts cost in batteries but we didn't have to worry about them running out anymore or having to change them at inopportune times, and there was certainly less waste with the plugged in approach.

If you've been considering this mod I hope this helps. There are also a number of videos on YouTube that also cover similar mods with the same or similar swings, apparently I wasn't the first person to notice this thing eats batteries...

If you have any comments or questions please post below!




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