In this contribution I want to show you how I managed to implement a solution using a slip ring into my M4A3E8. As I mentioned earlier there is not much room in the Tamiya kit of a Sherman tank. It is quite a challenge to add additional components in this tank model like a tank control board, a smoke unit, receivers, extra electronics etc. For implementing a 360 degrees turret rotation solution this is an extra challenge. The only logical place for doing this, is below the tower.
My requirements for the solution are
1) no destruction of cabling or cables getting tangled
2) must fit in the space available in a way that other moving parts continue to function without disruption
3) possibility to separate the tower from the upper hull (for maintenance reasons)
For my solution I used a mini slip ring with 12 incoming and 12 outgoing wires (I only need 11 connections) the main question was how to attach the slip ring.
In the Tamiya kit, the tower rotates by means of a motor with a gear drive attached to the upper hull. Below the tower itself, there is a knurled ring that exactly fits in that gear drive.
As the slip ring has the shape of a cylinder, the best solution would be the cylinder attached in the center of the knurled ring (as two concentric rings). The “tower”-side of the slip ring is then to be used as fixed point while the other side of the slip ring rotates when the turret rotates.
To attach the slip ring concentrically in the middle of the knurled ring I used a cap of a plastic spice jar. This cap should have following dimensions: height max. 25 mm and intersection max. 55 mm. This fits exactly in the tank and does not touch anything like the recoil mechanism if the gun is in the most upper position or other parts in the lower hull. It should be measured accurately and also be tested.
Before placing the cap, soldering of the wiring should take place: recoil mechanism, tower search light, elevation motor, LED machine gun and barrel LED flash light. Proper wiring is essential and to prevent “surprises” it should be checked and double-checked. I recommend to take notes of what wire colors are used for what.
In the middle of the cap I drilled a hole for attaching the slipring with a few screws. Two bended aluminum keeps the cap in the center of the black knurled ring. With some small bolts and nuts the cap is firmly attached to the bottom of the gun tower.
On the other side of the slip ring (the part in the tank) a connector comes in place to make a flexible connection with the IBU3 control board possible.
A 360 degrees rotation without disturbances works perfect and thanks to the connector it is possible to remove the turret from the upper hull.
I wish you all a merry Christmas and a wonderful and healthy 2023, cheers Easy8