Best bearing for jointer DJ 20?

[Joe McMahon]

I am going to replace the bearings on my DJ 20. Which type should I get, shielded or sealed? Also, any manufacturer suggestion? I don't want to byuy any far east junk bearings.

[David Kumm]

All companies make bearings in many tolerances. FAG, SKF, Fafnir,NSK, NTN, KOYO all make bearings that are more than acceptable for that machine. Most standard bearings are ABEC1 or P0. Precision bearings are ABEC 3/5/7 or P6/5/4. They cost a lot more. Standard clearance is CN if not specified on the box. C3 is often listed and it is loose clearance for higher heat or motor bearing applications. There are tighter or looser clearances but they are more unusual. Shielded or sealed in that application are personal preference as I don't believe the bearings are located in a dirty area. I consider sealed to be my last choice but that is just me. Most companies have several choices for what grease is in the sealed or shielded ones but I've never worried about that. The bearings in the machine are nothing special so anything better than standard ABEC1 is an upgrade. I usually don't buy old stock in closed bearings as grease can get old if the box has been sitting for years. I'd go standard clearance and if I could find ABEC3-5 or P6-5 I'd feel really lucky. If not reasonable I'd look at SKF Explorer bearings as they are made to approx ABEC3. SKF and FAG are all high quality. Dave

[Joe McMahon]

Dave, thanks I ordered a set of SKF 6004 & 6005 from Amazon.

Joe

[David Kumm]

Dave, thanks I ordered a set of SKF 6004 & 6005 from Amazon.

Joe

I wish there were more bearing discussions. There is so much to learn and I feel like I've only scratched the surface. Dave

[Joe McMahon]

Dave I know as much about bearings as I do about nuclear physics. Any help is appreciated. I know that bearings help things roll. When they don't do it smoothly, that is bad. That is it. I have exhausted my bearing knowledge.

[David Kumm]

Bearings in old machines are huge and were an important part in their design. Much more so than current machines. A key component almost never talked about. Dave

[joe maday]

From what I understand, Delta used both sealed or shielded from the factory. When speaking to a bearing supplier he said the sheilded has a higher RPM rating but at only 5000 RPMs it did not matter. When I replaced them in my DJ-20, the factory used sealed...so thats what I used...SKF's...around 18-22 bucks apiece if I remember

[jack forsberg]

6000 series bearings are the most common bearing being used and probably make of 60% of the bearings in light woodworking machines and motors. there cheap made in the millions and I can't think of one application that sealed would not be used for this common bearing.
Back in the day when shielded/felt seals were use you would see that the motor or machine maker often pumped grease in the bearing cap to hold the preload washer and let the oils from the grease enter in the outer edge of the shielded bearing. I think this made them last longer . shielded bearing (steel shield felt seals) clip in a grove of the inner race only and so do note have friction from the spinning outer race grove that the rubber seal bearings do. At motor speeds (3450 to 6000 rpm) heat is not a problem.

IMO the most lacking information on bearings is type/used. there is more to bearings than there size/dimensions and seals but most will only every come across a conrad bearings(the easiest Bearing to make) with a roller bearing on occasion.

[Joe McMahon]

David, I tried to reply to your PM but it said that your in box was full and kicked my message back. My place is in Lac du Flambeau. I have a small (16 X 20) shop but it has in floor heat and I use it all year round. I pass Highway 8 as I head north on 51 on the two lane.

I also cancelled the Amazon bearings and ordered standard clearance ABEC3 bearings from McMaster Carr for just a little more cost.

Joe