How to make a Lipo quick change battery for the TM Sopmod M4 with recoil, out of a standard TM 8.4v 1300mah battery.

1. Taking apart the standard TM battery:
Take your Standard 8.4v Tm quick change battery, underneath there is 6 holes, top middle and bottom, some maybe under the stick that’s on the battery. Using a small Philips screw driver, undo all 6 screws, and using a knife cut down the edge of the sticker to separate the two half’s of the battery. Now you should be able to tip out the contents of the battery.
Lipo battery mod picture 1

2. Making the quick change lipo battery:
Now you should prepare the new battery, take the old insides of the TM battery and look at the top section, it’s a flat metal bar, which loops over from one side of the battery too the other and in the middle is the quick change connector. This is what we need to remove and fit to our new lipo battery. Using a soldering iron where the wires join the metal just touch the soldering iron against it and the wire will drop off. Do this for both sides you will now have your quick change connector separated. Now in true blue peter style, discard the old contents of the battery out the way, keeping the quick change connector. Take either the hotpower 7.2v 3000mah lipo or the hotpower 11.1v 1600mah lipo, both crane stock batteries, available at ehobbyasia, ebay and other stores. You’ll need to slide the crane stock lipo into the sopmod stock. Notice how it is a perfect fit, and also how you can’t fit the battery the wrong way round. Also notice the length of the wires, how they stick out quite far from the top if you cut the main lipo connector off, and fit the metal quick change, you’ll notice there will be too much slack wire for it to be a snug fit. Line up the quick change in the quick change slot on the sopmod stock, while the lipos in the stock and mark on the wire the proper amount you will need to cut. This will leave the wires pretty short don’t worry it needs to be. Now using your soldering iron, solder the lipo wires to the quick change connector. Please make a note at this point about polarity, while the lipos in the stock fitted correctly you should mark it and make a note of what side is positive and what side is negative save you getting it wrong. When you solder the wires to the lipo use some heat shrink to cover the new soldier contacts. This should now give you a lipo battery with a quick change connector, give it a charge up and test it in your sopmod. Please note you should do anything to the little white balance “tab” that comes off the lipo you need that to balance your lipo, when fitting the stock cap, use your common sense balance the tab on top of the connection and the stock cap will click in place.

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3. Adding an outer case to the lipo:
This is good and should now be working but as you can see its only as solid as your solder contacts are. So we now need to mod the left over casing to give it some extra protect and make it a bit more robust. Take the battery and drop it in the stock again, notice how much spare room you have in the stock once the batteries fully in, now drop the empty sopmod case in there and mark on the case where the top of the lipo battery was, we are basically going to chop the top section of the sopmod case and fit it over the lipo quick change connector. This if you get it as close to the lipo as you can will give it lots of support with very little movement. Once you have marked the case where to cut, take a hacksaw or dremel and cut the marked section of the casing off. Now try and fit the cut section of the casing over the quick change connector on the lipo, notice how it fits but catches in a few places. Take a dremel or file or knife and cut away the inside parts of the connector. There’s divides and parts that just aren’t needed. Remember to keep the screw holes intact as the screw will hold it all together. Keep removing material until the wires and metal part fit. You will have to cut a tiny notch in the top to fit the lipo balance tab.
Hopefully now your battery is coming together like this one pictured below as the final result. As you can see take your time and the end result will be as good as you make it.

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Lipo battery mod picture 10

These can be made to order on request by emailing info@eagle6.co.uk and only cost £60 each, which costs less than 2x std sopmod batterys which you would need for days play. can be made in either 7.4v 3000mah or 11.1v 1600mah