6/7/8/9/10 AA battery pack rubberband secured (remix of 6 x AA Battery Pack by NozzleClog)

thingiverse

I was making a battery pack to replace my dead 7-cell NiMH pack in my airsoft rifle, when I made the original battery pack, I experienced power drops that I thought were due to a lack of power because of the low cell count, so thinking I needed more batteries in my pack, I made some pieces to add batteries. It wasn't until after making a piece to give me 7 batteries that I realized my problem was in the springs - it turned out I had bad solder joints on the springs, and I just couldn't get the springs to tin properly. So when I probed the power while testing the rifle, I was having power drops when I tried to draw power from the pack. At this point, I had already totally disassembled my airsoft to see if anything was wrong internally and didn't see anything that would be harmed by an extra 1.2V of power, so I decided to try using rubber bands on an 8-cell pack. After some experimenting, I found that I could use the same cap I made with ears for the rubber bands and secure the bands to the screw at the other end of the 6-battery tube, and it worked fine that way - although a little slower. The file titled "8AA-battery-cap_(+2_for_springs)" is the file to use if you have good spring contacts, but if not, you can do as I did after realizing my problem: make some square copper contacts and modify the STLs to use rubber bands. You don't have to modify the STLs! The file titled "AA-battery-case+2-" is a piece you can add to the original tube to add 2 batteries - I believe this is properly sized so that you can add as many as you feel the need to add, but I haven't actually tested that. The file titled "AA-battery_case-_+2-W-end-cap4(and_plane_to_print_without_support)" is my solution to the problem of no usable springs. It has ears on the sides to secure the end cap with rubber bands pulling tension for a good contact with simple copper contacts - you could probably even get away with just using coils of stripped wire in the endcaps. Please note that if you separate the end cap from the +2 extender, you will end up with an extra plane or flat rectangle that I set into the battery tube part at the height of the starting point of the tube. I did this so that it would have a solid printed layer at this height - as can be seen in the pictures - so that the print can be done without support and standing vertical as it is oriented in the .stl file. The file titled "8AA-battery-cap-(4mmholes_at_18.5mm)" is the piece I used to mount the pack to my airsoft - I used a pair of screw holes that were used for a piece of rail, but I could re-do this in the future to actually use the rail. I will also include the original files by NozzleClog: "extra-battery-cap-for-6-to-7-cell-converter-stl" is a file that has the mounting screw holes and a single battery slot that I made so I could do a 7-battery pack as the original battery pack called for, but I don't believe it's necessary at this point because my airsoft works fine with the sliding rubber band secured cap on 6 or 8 batteries - and I don't really think it's necessary to make it 7. If you wish to use it, I'm not really sure about the length spacing, you may need to modify it so that you don't have to use a spring. It has a channel built into the side so that the wire can ride in the slot and go from one contact to the other.