Disable router capability on Time Capsule

The setup that you ask about is not officially supported by Apple.....they expect you to use the Time Capsule wireless to back up......so while the setup below should work.......this is not the same thing as saying that it will work.

Connect an Ethernet cable from one of the LAN <--> Ethernet ports on the new router to the WAN "O" port on the Time Capsule.

Open AirPort Utility on your Mac (Finder > Applications > Utilities > AirPort Utility)

Click on the picture of the Time Capsule

Click Edit in the smaller window that appears

Click the Wireless tab at the top of the next window

Change the setting for Network Mode from Create a wireless network to Off

This will turn off the wireless function of the Time Capsule

Click on the Network tab next to the Wireless tab

Make sure that the setting for Router Mode is set to Off (Bridge Mode)

This will turn off the routing function of the Time Capsule

Click Update at the lower right of the window and give the Time Capsule a minute to restart

I still want to back up my Mac wirelessly but I don’t want the time machine to be my router anymore. Is this possible?

My answers above assume that this is exactly what you wanted to do.

1) Use the wireless provided by your "main" router for backups to the Time Capsule

2) Not use Time Capsule as a router....or.....to provide a wireless network.....and use the Time Capsule only as a hard drive for backups

Please check my answer above regarding the Network tab to see that setting up.....(or making sure).....that the Time Capsule is set up in (Off) Bridge Mode will insure that the router functions for the Time Capsule will be turned "off"......so it will not be acting as your router.

My answer above regarding the Wireless tab assumed that you wanted to use the wireless provided by your "main" router to back up to the Time Capsule.....and not use the Time Capsule wireless......so the Time Capsule would simply act as a backup hard drive.

IF......you meant to say that you still want to back up to the Time Capsule using the Time Capsule wireless function......then you would leave the setting for the Wireless tab set to Create a wireless network. Then, you can use the Time Capsule wireless to back up......even though it will not be acting as your router.

(Some users have difficulty understanding that the Time Capsule can still provide a wireless network....even if it is not acting as a router)

However.....if you enable the wireless on the Time Capsule.....and.....your "main" router also provides a wireless network signal, then you are going to have two wireless networks.....one provided by the "main" router and the other provided by the Time Capsule.

Having two wireless networks may be confusing for some users who only want one wireless network.