grinding noise after installing heated bed

#1
The heated bed gets stuck and makes a horrible grinding sound when attempting to initialize and level the printer in preparation for a print. I think I nudged the mounting frame while slipping the heated bed into place and I'm afraid that it's now grinding gears or something.
 
#2
More then likely your bed is to far to the left or right depending on which side its getting stuck. In my case I was ever so slightly too far to the left gave it a snug push to the right and I was fine. Its a very tight fit for the heated bed but it fits. Also make sure no wires are in the way.
 
#3
seemed to work on small objects .. i then printed out a bottle seemed ok ... i then tried to print out a more complex stl an all hell broke loose , once again it was hitting the model , shuttering an a loud bang noise , it was so violent the whole machine was jumping ... it lifted the platform an dropped it down the started to print everything 3 -4mm away from where it was suppose to be ... I stopped the print immediately . when i was taking off the perfboard I noticed the bed was slightly rocking front right hand corner an back left hand corner .. I looked at the bolts holding the heat bed to the arm an tired to make sure they were secure , the front bolt was just going round an round an would not tighten at all .. so i took the heat bed off , at that point i noticed the arm itself was also moving up and down about up to 4 mm , I sent a email to the support company here is Australia yesterday but have still to hear back from them.