2 X AA Battery Holder - No Springs Required - Two Versions

Additional materials required :

Three pieces of 24 gauge (0.644mm) wire, length as required for your application. I used multi-stranded wire.

There are two versions of this model :

• Version V04 has walls of minimal thickness - uses less material, faster print time
• Version V04B has thicker walls and is a bit sturdier - uses more material, longer print time

In addition to the above, each version can be wired with the wires on either the top or the side. There are four parts to each model :

• Contact (2 required)
• Case
• CaseTop

Assembly and Use

For the bottom contact, prepare a length of wire about 150mm long by stripping the insulation from the 24AWG wire (of course equivalent un-insulated wire can also be used). Since I used multi-strand wire, I twisted the bare wires together after stripping the insulation.

Using one of the two contact pieces, wrap the wire around both sides of the contact as shown in the photos. Note that the wire is continuous from one side to the other - this will connect the two AA batteries in series.

Insert the bottom Contact assembly in the Case with the “high” side oriented toward the + symbol on the side of the Case. Use a screwdriver or similar tool to push the Contact plate firmly to the bottom (push only in the center so as not to break the wire-wrapped “fingers”). As the included CAD screen-shots show, the bottom contact is oriented to the reverse of the top contact. It is important that both Contact pieces be oriented correctly.

For the top contact, prepare two lengths of 24AWG wire (one red positive and one black negative wire are standard). Each wire will need about 80mm of un-insulated length, plus whatever additional insulated length is required for your application.

For wires coming out of the top:

• Wrap the un-insulated end of the positive wire around the “low” side of the Contact piece, and then thread the insulated end through the hole in the center of the Contact piece; be sure to leave a short insulated portion on top of the Contact piece. Do the same for the “negative” wire and the “high” side of the Contact plate.
• Thread both wires through the hole in the top of the CaseTop piece, and while pulling the wires through the hole, seat the Contact piece inside the CaseTop.

For wires coming out of the side :

• Wrap the un-insulated end of the positive wire around the “low” side of the Contact piece; be sure to leave a short insulated portion on top of the Contact piece. Do the same for the “negative” wire and the “high” side of the Contact plate. 
• Thread both wires through the hole in the side of the CaseTop piece, and while pulling the wires through the hole, seat the Contact piece inside the CaseTop.

With the CaseTop and top Contact assembled, insert one battery + side up into the + side of the Case, and the other battery + side down into the other side. Place the CaseTop on the top of the batteries (be sure to orient both + signs on the same side), and push the CaseTop down firmly so that the “ratchets” on the side of the Case engage; push down until you feel a bit of “spring” as you push.

Print Instructions

Print in PETG using the 3mf files provided, otherwise :

• 0.2mm layer height
• 3 perimeters
• no infill

Print the contacts on their side, with supports.

Note : I printed this model in PETG as it tends to be a bit “springier” than PLA. It is possible that this model might work printed in PLA, but I have not tried this.

CAD

The OnShape 3D CAD files for this are here :

https://cad.onshape.com/documents/fcb104a56d2f9994531d978b/w/4c2bc5675ce1873c8d50061d/e/0bfcfcf6c7c398b78a99cfca?renderMode=0&uiState=66ff1ef851772e3810e77a31