by The Saw Doctor
Ever had a bearing on your router bit where you’ve had trouble getting the bearing off?
I had a customer recently who was having trouble getting the bearing off the bearing shaft on his router bit. I thought I’d share with you the methods that I use to remove bearings that are stuck to the router bit.
There’s numerous reasons why the bearing becomes stuck on the router. Moisture from the timber and also from the humidity in the atmosphere forms between the bearing and the steel on the bearing shaft of the router. As you know this becomes surface rust which makes it difficult to remove the bearing.
The flush trim bit is the most common router bit to have trouble with getting the bearing off. The reasons for this is the flush trim bit is used on multiple types of materials more so than other router bit.
The worst clogging of material around the bearings is glue when trimming either the edge strip or laminated bench top because of the excessive adhesives that are applied.
The way I remove the glue on the outside of the bearing is to use a wire wheel on the bench grinder.
Care has to used here, as you want to hold the router so the tungsten tips are away from the wire wheel. If the wire wheel comes into contact with the tungsten it can chip the cutting edges and more tungsten has to be removed when sharpening.
Once the glue has been removed from the outside surface it’s time to remove the bearing. Removing the bearing from the router can go two ways, the bearing either slips off without a problem or the bearing is stuck on good.
The latter is usually my luck and a couple of "choice words" come in handy as well whilst your trying to get the bearing off.
The first step I try is to place the bearing in the engineers vice with the tungsten tips facing away from the jaws of the vice. First you need to loosen the screw, I tighten the router into the vice to undo the screw.
Loosen the screw so that there is about 2 - 3mm of the thread still in the bearing shaft.
Adjust the jaws until the jaws are just touching the body of the router. This allows the bearing to sit on top of the jaws.
Remember keep the tungsten tips facing away from the vice jaws.
Hold the shank of the router to keep it steady and tap the head of the screw with a hammer. This will move the router downwards and make the bearing become free on the bearing shaft.
Once you have loosened the bearing remove the router from the vice.
Remove the screw and bearing. On the underside of the bearing there is usually glue on the bearing that has dried, you can usually remove this by using your thumb nail but if that does not work try picking the glue off with a Stanley knife blade.
Be careful that you don’t cut yourself, take it from me… It hurts!!
On routers bits other than flush trim bits. I usually firmly hold the router in the engineers vice and use a screw driver to prize the bearing off the router.
If there is only a small amount of clearance between the bearing and the body of the router, get an old screwdriver and grind the tip of the screwdriver so it is thinner and will fit in under the bearing.
The next procedure which helps for the next time you have to take the bearing off the router that you should do, is to get a cloth and put oil onto the cloth and then smear the oil around the bearing shaft.
Also put some oil onto the screw, don’t drown the screw in oil just put a little oil onto the first couple of threads on the screw. Then screw the screw into the bearing shaft. This will lubricate the thread and stop moisture forming in the the thread which over time becomes rust.
Putting oil on the screw also makes it easier to remove the screw especially if the screw has not been removed for a few years.
Hope this helps you next time you have a troublesome bearing to remove from your router bit. 😊