sheilded vs sealed

[joe maday]

I'm installing a segmented cutter head in a DJ-20 jointer and of course will be replacing the bearings. I have not taken it apart yet but was wondering should the bearings be shielded or sealed? Does it matter? The cutterhead comes without bearings and i won't be taking the machine apart untill the head arrives, so I'm not sure what it is the machine now.

[Erik Loza]

"Sealed" is what we use.

Erik Loza
Minimax USA

[Glenn Bird]

Sealed bearings are what you want. Shielded only keeps out the larger dirt particles and will fail sooner.

[jack forsberg]

Shielded bearing are still used today and there are reasons most of them have to do with heat. today sealed (rubber) are viewed as better bearing only as they keep the bearing clean. Its is important to note that there are more to bearings than how they are protected from contamination. To answer your question you most likely have rubber seals now in the machine. it is also important to note that there are different types of bearing and not all types come in a rubber seal option. for Conrad type bearing( most likely what is in your machine) i would get rubber seals.

If i had a question on the bearings for your DJ 20 it would be do i need bearing with better thrust loads that the helical head will put on them? something to ask the Head manufacture. My guess is that they have an opinion about that in larger heads than the 8" but you never know. That is if you want them to last longer .


jack
English machines