Hey technopro , you should be able to modify a tower pro 995 as a continuous servo for your rotation needs. On eBay search for buck step down converters. I bought 8 amp versions which should be enough for you. Also I wouldn't run servos over 7.2 volts so they don't get hot or burned out.

Buck step down regulators are perfect, as has been said. But make sure you check the stall current of the servos you will use off of them so you don't come up short, for instance if the regulator is 5A and your servos have stall current of 4A each, running 2 off of the regulator may not be a good idea, you would want one per servo. If on the other hand the stall current is 2A then one regulator for every 2 servos would be fine.

When you say rotating a load of 5lbs, what do you mean? Is it a drive train or is it an arm lifting?

If it needs to lift anything then work out the distance from the pivot and find a servo with enough torque to lift the weight at the specified length (i.e. if it's 1 inch from pivot a 5lbs/inch servo will do, if it's 10 inches away you will need 50lbs per inch)

Rich, The servo is flat and level(mostly) and faces straight up(like I said, mostly). im mounting a head on it that only needs to be rotated 180*. One heavy duty servo for the head and one micro for a ping sensor. im thinking, would the servos in the store work for this?

For the voltage reg. it needs to have an Voltage and AH output that can run a heavy duty servo, micro servo some sensors, and the ez-b itself.

Thanks for all the replys and help! This is just technical stuff for my big surprise project!

Moving the head horizontally shouldn't require much torque since it's not going to be working against gravity and doesn't actually have to lift anything, still a heavy duty servo would cover any issues it may have.

I'd use more than one regulator personally, it'll avoid any issues. Just work out the load of the kit you plan to attach to it and get a regulator (or regulators) that provide more than the current needed. Oversize the amps and it'll avoid heat issues too.

Ok. Well I may leave this unsolved in case anyone finds something. So to recap:

Voltage regulator: adjustable output, 12v 7.2AH down to something the ez-b can handle,

Servo: may get the one out of the store when it opens.

Rich, the head is round and sits on a 25 to 35* angle. All it needs to do is rotate. Because theres no weight change on either side I can assume I don't need to go to an extreme servo with crazy weight ratings.

Thanks for the help guys!

@technopro just take note that EZ Board V3 does not need a regulator dropped from 12 volts. It runs on 12 volts great!

I thought that 12v was the max voltage for the v3 so I figured why not help it stay cool and give it a regulator? also, with the sla battery giving 12.3-11.8v I thought that it might be a little over the top for the ez-b. but any which way I need a regulator that I can adjust to run the output at 6v for a heavy duty servo.

The EZ-B V3 can run on 5v to 17v without any problems.

Technical manual here

EZ-B Version 3.1 Input Voltage (min): 5 Volts DC Input Voltage (max): 17 Volts DC Input Voltage (recommended): 7.2 Volts DC @ 3 Amps