Overhaul of a 9" SB model "A"

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Hi,
Great restoration on your SB!
I have a question about my SB 8" Junior lathe.
The spindle needs to be turned down a bit because of scoring wear and these lathes never have bearings, other than a hardened spindle and cast iron bearing caps.
I need to line bore the spindle frame bearing caps and install bronze bearings.
With your knowledge of your SB, I thought you could give me some information.
Thank you,
Giovanni
 
you were told over on PM that it wasnt really neccasary, you should just take down the high spots and run it. if oyu dont like how it operates then worry about all of that. it wont be an quick and easy job to bore out the headstock oversize press in a bushing and re bore that to proper spec of what you have turned the spindle to. if that doesnt sound like a lot then you also have to remember that you are trying to get extremely tight tolerances without moving the spindle up down or side to side of the OEM spindle axis. if you do get it out of the oem axis then the tailstock will need to be machined/ scraped to suite the offset as well as the saddle.

like others have said and i will say just run it, i have seen much worse then what urs looked like and the oewners have and still are running them happily to this day
 
Agreed. It's one of the reasons I rarely come to HMEM anymore. I drop in from time to time to see what's happening but.....
It seems many of the really good informative threads are now missing their images.
 
Hi,
Great restoration on your SB!
I have a question about my SB 8" Junior lathe.
The spindle needs to be turned down a bit because of scoring wear and these lathes never have bearings, other than a hardened spindle and cast iron bearing caps.
I need to line bore the spindle frame bearing caps and install bronze bearings.
With your knowledge of your SB, I thought you could give me some information.
Thank you,
Giovanni

giovanni, in the engine rebuilding world we recondition the block by grinding a small amount off the cap on the mating surface then normally a hone is all that's needed to bring things back into spec. the hole can be a little egg/football shaped, it is beneficial on a full sized ic engine but that doesn't apply to your lathe. to avoid an egg shaped hole you can take a decent amount off the cap then bore then hone. you can also scrape it to fit instead of honing in which case you can create clearance on the top and bottom as well as the parting line so you have 4 points of contact and you can fine tune the clearance in each direction. muller nick has good videos on scraping on youtube, same screen name.
 
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