Quoted from MutterFudder:I seem to have THE worst luck on magna mount adherence of anyone I know. I purchased brand new magna mount rails for two games: one with no sideblades, one with Stern factory blades on them, because they keep peeling off the side of the cabinet. I wiped both sides of the cabinet with alcohol rub and let dry 30 minutes, then installed the mounts and left them with light bars off for a day. Within a day of attaching the bars back, both bars are back drooping off the side walls again. Anyone use anything "extra strength" to mount your magna mounts to the sides of cabinets?
Oddest thing too. I have two other sets of Pinstadiums in two other machines. NO issues with those staying put. Guess these are just extra heavy
I would first check to make sure you are using the black ribbon cable mounts provided with the kit. They need to be installed properly near the top of the backboard on the rear at the furthest top left and top right corners(backside).
Also make sure you have the proper amount of slack(approx 6"-7") on the ribbon cable between that clamp and the rear where the ribbon cable goes into the light bar. Too little slack will cause slight pull on the Magna-Mounts and with heat and vibration from the pinball that will cause the adhesion to fail. Also if you don't press the new mounts on extremely firmly(I mean super super firm is important) then they will not adhere properly. Use your thumb on the inside of the cabinet and then grip with your fingers on the outside.
On occasions certain runs of the vinyl side art from the manufacturer can do what is know as off gassing. Over time that can break down the adhesion of the Magna-Mounts which will accentuate the above mentioned techniques for proper mounting.
You have 48 hours before the adhesion on the new Magna-Mounts fully cure so you can "try" warming the mounts up (using a hairdryer or medium/low setting on a heat gun) to re-activate them. Once that is done, then immediately press the new mounts VERY firmly onto to side of the cabinet. Let it sit for 48 hours without the light bars mounted.
I would re-check these mentioned items and perform the recommended steps, then email me directly if you need further help.