Bad bearings? Dah Lih circa 1976 Taiwanese

I have used a lot of 7200 series bearings. They are mostly a thrust bearing, one side is cup, one side is cone. So how you put them is important. I've seen millwrights put them in backwards. Sometimes it's pretty easy to look good. On one common use ,we used two, back to front. We never had any 7200 with seals. Your top bearing should have a seal to close in the cavity . I wouldn't worry about the bottom. But I would use a super premium grease like Mobil 101. A problem that is in some designs the preload is governed by the dimensions of the nut and housing. When either wears or is over tightened and hammers out, the preload is reduced. I've seen that slop more than a few times.
 
I have used a lot of 7200 series bearings. They are mostly a thrust bearing, one side is cup, one side is cone. So how you put them is important. I've seen millwrights put them in backwards. Sometimes it's pretty easy to look good. On one common use ,we used two, back to front. We never had any 7200 with seals. Your top bearing should have a seal to close in the cavity . I wouldn't worry about the bottom. But I would use a super premium grease like Mobil 101. A problem that is in some designs the preload is governed by the dimensions of the nut and housing. When either wears or is over tightened and hammers out, the preload is reduced. I've seen that slop more than a few times.
Yes the top bearing I got was reasonably cheap and sealed both sides. The 2 very top 6208 bearings I also got sealed both sides but the 2 7207 angular contact bearings only came non sealed. They said if I wanted them sealed they would have to make some enquiries overseas and were talking big money. Here is the grease I got which they said was the "Rolls Royce" of bearing grease.
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Over the years, I 've used a few hundred of that brand of bearings. I would trust them. That's OK grease, but it's not the RollsRoyce, just priced like it. I've used it, it was specified in the new German machines. I didn't notice that you are kitty corner across the ocean from me, so that was why I recommended the American Mobil 101. In machine design, there is a lot of common practice . I've joked " A chunk of iron is a chunk of iron." You are going to want some axial preload on the 7200s, none on the 6200. One of those empty beer cans roaming around your shop can be used for a trial shim. Much like car wheel bearing, it's a feel. If you need a shim, use steel, or at least brass.
 
Over the years, I 've used a few hundred of that brand of bearings. I would trust them. That's OK grease, but it's not the RollsRoyce, just priced like it. I've used it, it was specified in the new German machines. I didn't notice that you are kitty corner across the ocean from me, so that was why I recommended the American Mobil 101. In machine design, there is a lot of common practice . I've joked " A chunk of iron is a chunk of iron." You are going to want some axial preload on the 7200s, none on the 6200. One of those empty beer cans roaming around your shop can be used for a trial shim. Much like car wheel bearing, it's a feel. If you need a shim, use steel, or at least brass.
How would you pack the grease? 1/3rd pushed right through?
 
If the design doesn't allow for preload, so be it. But do check for wear in the housing or the nut.
 
So I'm going to have a crack at fitting these new bearings tonight. When I took the old ones out, the side of each bearing with the writing on and thicker outer race were facing each other. These new ones have the writing on the inner race on the other side. Does anyone know if the thicker outer race's face each other? Photo attached of new bearings.

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It's a cup and cone, the outer race is the cup,the bottom of the cup is the fat side. This has to bear against something, like a housing. Machines are many simple parts, so think about what it supposed to do. As my old partner would say "What are you hoping to accomplish?" There is no guarantee the guy before you put it together right.
 
So I'm going to have a crack at fitting these new bearings tonight. When I took the old ones out, the side of each bearing with the writing on and thicker outer race were facing each other. These new ones have the writing on the inner race on the other side. Does anyone know if the thicker outer race's face each other?

Maybe this will help:
 
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