Trouble cutting bearing pockets

One more method: Just bore thru and press in flanged bearings
Mark S.
 
Would a draw-bar version of something like this (plus an adapter plug turned to the ID) work as an open end mandrel?

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Simplified process:
Face and bore / ream stock to the appropriate diameter
Cross-drill and thread for a set screw or two
Mount stock (on the adapter plug) and turn the OD and the bearing pocket
Flip the part, take a skim cut to check for alignment issues, face and cut the 2nd bearing pocket.

I like this idea as it has long-term versatility, but I don't know if the 5/8-16 threaded section of this 3mt blank would hold up to machining a 2"x 2" aluminum cylinder.
 
I've made ten so far (two batches of five) and will be making another 5 soon. Still boring from each side, and lining up a reverence mark on the same jaw. I know this isn't the most accurate way but the mechanisms have all worked well so far. I ran out of drops from the scrap yard and ended up buying a 5' length of 2" 6061-T6.
 
If you bore all the way through, even undersize, you can use a center in the tailstock to center the work in the chuck after you flip it round. Should get you very close. But as a rule, planning your work to only have to chuck a part once is always the best if possible.
 
Thanks. I have been boring all the way through but will make a point of bringing up the live center cone as well upon reversal.
 
I make hundreds if rollers per year with bearing bores in each end that will be mounted on a shaft during assembly.

If possible bore soft lathe jaws to hold the parts, this has the added advantage of leaving little or no jaw marks on the part.
If possible use an adjustable chuck.
If mounting the finished product on a shaft of questionable size and roundness use what is often known as "Bearing Quality Bar" stock, turned, ground and polished, this is not to be confused with TGP material for general use.
 
If you need a shoulder for the bearings to butt up against and have to flip it and re chuck it. Make a pass with your boring bar through the part and when you flip it to the other end indicate off your bore and machine the second bearing pocket.
 
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