Bought mine a few years ago, but mine is 12 inches center to center of the two bases.
The nie wieder bohren system is recommended and warrantied for use on natural stone, tile, glass, metal and concrete surfaces only.
Yes. They require a flat and clean surface like tile. Ours are in a shower where they get wet but are not submerged in water.
As base plate is glued to the tile with a two-part epoxy (provided). I installed for my parents' shower 2+ years ago. Still adhering.
The bar should be removed, the glue cleaned off the ends and on the wall. Clean the surface thoroughly and repeat the installation process. This time make sure sufficient time has passed (24hours +) before the bar is put onto the anchors. My experience with the bar slipping was due to insufficient wait time before I attached the bar ends to the anchors. It slipped after one day. In your case I am wondering if the 30 inch bar, having more weight than shorter bars may be the cause of slippage. Insufficient cure time will make the anchor not stable. Slipping after several months may be caused by marginal cure time plus the heavier 30 inch bar. Good luck with the re-install.
1-1/2" as required
You can loosen the bond by using a razor knife around all three sides. You can then use some acetone around the adapter and wait 30 minutes and then use long handled pliers to apply clockwise torsion to remove.
The nie wieder bohren system when installed correctly is fully ADA compliant and rated at 250lbs.
You can mount vertically, horizontally or diagonally provided the surface is level on plane
buy another one! you would have had to put an awful lot of weight/pressure on it!