Need new rotary axis

[JeffJ]

Hello!

I am new to this forum and I am wondering if someone can give me a little guidance.

Our company recently purchased a new ACT DMCIII mill with an added rotary 4th axis. It was advertised as having "zero backlash". Turns out that true zero backlash may be a myth. We went through two of these axes and the backlash was so bad that we even tried securing them with bungee cords to minimize the issue.

We've been running three other Maxnc-10 units and their 4th axes run pretty well. But the backlash is adjustable on those machines.

Can someone suggest a good, out of the box rotary 4th axis that has minimal backlash or is adjustable to 0? I am not an engineer so I am not looking to redesign an existing rotary table. I just need a 4" 4th axis that will work properly with the new machine.

Appreciate any comments that anyone has.

[Petro]

Not an expert by any means in this area other then maintenance. However each indexer generally has some type of clamp to hold the indexer in place. It may be either air clamp or hydraulic. If the table is not sized properly they can move during machining. Since the rotary tables generally have a worm and wheel combination. They can usually be adjusted either by grinding down a shim/washer to get the proper backlash down to almost zero or a physical adjustment for engagement of the worm. So from this aspect all are in a sense created equal. Always buy one with an air purge that pressurizes the motor area to keep coolant out.

Hope this helps!