The Talking Machine Forum — For All Antique Phonographs & Recordings

I've bought and restored four cheap #5B or portable soundboxes with new ball bearings, polishing the bearing inserts, new diaphragm seals etc. for my floor model orthophonic machines and they work fine. One is noticeably louder than the other two so mostly I use that one. But the only #5 I was able to find cheap so far ended up being unrestorable when I attempted to restore it, because the main case was just too cracked and it busted up. The rest of the parts are there though.

Question - would it be worth it to convert one of my 5Bs to use the less tapered bearings from the 5? I'm speaking of whatever you call that magnetized needle bearing rod that is driven thru the base of the needlebar. I notice that on the 5, the balls ride quite a bit farther out from the needlebar. So I'd think the 5's needlebar would be more precise, what with the bearing/balls contact points being farther apart. But if it wouldn't result in noticeable improvement I'll just forget about it. Plus I'd have to find out the best way to drive the 5B needle bearing out and drive the 5's in without risking bashing something in the process.

Thanks!

So far all I've done just in case I decide to try this is to polish the 5A's two needle bearing 'cones'. Geez I've rebuilt 4 of these orthos but I never paid that much attention to the condition of these bearings, since all the do-it-yourself instructions I found at most only involved cleaning and/or polishing the bearing rings, then cleaning the needle bearing as best you can, while it's still mounted inside the case with the needlearm.

I carefully knocked the 5A bearing out of the needlearm. Removed and up close this 5A's bearing looked God AWFUL! Deep circular gouges and scratches going around it on both sides, corrosion, and pits from the balls digging into them. Yuck. So... I mounted each side into my dremel & polished the bearing surfaces with finer and finer sandpaper, then polishing compound and metal polish. At dremel speeds it only takes a few minutes even with this hard metal. The two bearing cones now look like friggin' chrome, success! Of course the process did remove a slight amount surface metal to get past all the pits and gouges, but since the ball bearings find their own height on the cones anyway I can't see it mattering. Working on doing same polishing out of the rings next.