Oster Classic 76 "Blade Rattle" Issue
The Part That Needs Replacing...
One of the most common issues of the older Oster Classic 76 hair clippers, particularly from the "blue box" generation of these clippers, is the 'blade rattling' issue. If you've experienced this issue, it is due to the construction of the hinge assembly's screws and anchors.
Basically, after regular usage over the course of a couple years, the older generation of Oster Classic 76 hair clippers have hinge assemblies (pictured on right) that start to seem "off center," causing the blade to make an awful rattling noise. The blade will visibly wobble left and right at a high speed and will be very apparent with the sound it makes.
Have you experienced blade rattling with your Classic 76?
What Causes Classic 76 "Blade Rattling?"
This is due to a manufacturing flaw with this specific generation of clippers, and is very difficult to fix as a long-term solution. The flaw is found in the assembly's screw anchors, which were never properly secured into the clipper unit. They start to come loose after prolonged clipper usage. This typically happens with one of the two screw assemblies coming loose, which causes the most dramatic blade rattling.
It is a destructive issue as the continual vibration of the unit will damage the unit every time it is used. It is also potentially dangerous, and you will be using hair clippers with a blade that is no longer perfectly centered.
A Common Issue with Late 2000s (or Earlier) Models
As previously mentioned, this is a common issue only with Oster Classic 76 clippers that came in the older powder blue colored box, and it is no longer an issue in the newer ones packaged in silver boxes.
The picture shown here is of my Oster Classic 76 "blue box" model purchased in 2008, which was damaged due to blade rattling. Here, I'm illustrating how the entire hinge assembly mechanism, including not only the screws but also the screw anchors themselves, were simply pulled outward and removed.
While it may be difficult to see in this picture, the plastic portion under the hinge assembly has numerous abrasions from blade wobbling.
Attempting to put the entire hinge mechanism back into the Classic 76 is effortless - the anchors slip right back into their drilled holes, and this should never be. Those anchors should be permanent fixtures in the clipper, and unable to ever be removed.
Poor Manufacturing Leads to This Eventual Issue
In my opinion, it appears as though Oster manufactured the Classic 76's hinge screw anchors to simply be held in place with a metallic 'pyramid tooth' texture applied to the outside portion. They were, in no way, soldered into the unit or held with any kind of adhesive. Over time, the constant vibration of the blade wears down the plastic within the drilled screw holes, making them wider on a micro-scale and providing just enough slack to make the hinge assembly become looser, and therefore, make the blades start vibrating.
Vibrating blades in these clippers is extremely damaging to the entire unit. When a blade wobbles uncontrollably, it creates an angled friction that will eventually damage your blade, and runs a risk of bending the hinge assembly and wearing down the top-most plastic surface of the clipper itself.
Silver Box Classic 76
Fixing Wobbly Clipper Blades
Fixing this issue is difficult; you cannot simply solder or super-glue the anchors back into their drilled holes and expect it to be a long-term solution. This is a precision instrument that requires perfect balancing so that the blade surface is perfectly straight.
It is possible to secure the mechanism into place if the plastic around the screw holes are still in-tact: simply insert a new hinge assembly and the old screws and anchors (these are metallic and will not be damaged) and fasten them firmly back into place.
This is a short-term solution, as whatever adhesive you use eventually wear down due to the clipper's vibration. Your best bet is to simply replace the clipper with one of the newer Classic 76 silver box models, which do not have the screw anchor issue and will not rattle or wobble free after regular use.