If the esthetics annoy you (and they would me as well) I would correct them as best I could myself by refacing them on the lathe. It just depends on how far out the features are how much they bother you. If it is really bad I would look into getting it exchanged. I find using the alignment rings and a rule to be quite a time saver myself and far less fumbling with a part to get it close. The original Harbor Freight 4 jaw chuck that came with my lathe was pretty bad. Even after getting the jaws out the adjusting screws would still lock up in the chuck body and wouldn't turn. I spent a couple of hours deburring every jaw, every screw and the bores/retainers in the chuck body for the screws. Several needle files and some slip stones paid off big time in making the chuck usable for something other than a door stop.
03-23-2022, 03:34 PM (This post was last modified: 03-23-2022, 03:35 PM by vtsteam.)
Well, unfortunately the beauty is skin deep. Here's an example of the jaw and screw threads. The jaw threads actually look cast, and the marks on the side look like bandsaw cuts to me. The screw threads are so rough, somebody on whatever device turned that out must have been deaf to chatter. I can't even trade jaws around because the threads are so bad. Three jaws run acceptable, as is, but the 4th has such bad tolerance that it rocks in its groove, which is the only way they drove that on that particular screw.
I'm going to have to live with this chuck, as the return date passed a couple weeks ago, and I threw away the box and packing. Heh, I spent too much time casting and machining my own backing plate in iron. It's a thing of beauty, but it was a waste to assume what it matches was made with any care at all. Basically the Shars 6" 4-jaw is just a lump of shined up surface ground metal surrounding a few hacked chunks more.
Yeah, I've been down that same road with a couple of lathe chucks and a couple of drill chucks too. Cleaned them up best I could to get them working and then tried to forget about it. It's the new world order I guess.
03-24-2022, 07:40 AM (This post was last modified: 03-24-2022, 08:39 AM by vtsteam.)
Me, too Ed. I still own an Enco mill.
I'm thinking I'd like to remake that screw, or all of them some time. That's not a problem, but getting them out and back in looks like it might be. The screws are retained by plugs, which are either press fitted or threaded into the chuck body. I can't tell which. There are inset allen screws at the perimeters of the plugs as retainers.
If those plugs are pressed in and the allen sockets were drilled and tapped after, then it seems like it would be nearly impossible to realign well enough to press the plugs back in place and have the retainer threads line up.
If the plugs screw in, that would be much easier. Or if they were a close sliding fit. Doesn't seem that way though, I took out one of the setscrews and the plug didn't budge when tapped lightly with a drift from the front face.
The plugs are drilled and tapped in the center, presumably for a stud to pull, or to trap with a stop nut if the plug is screwed in.
03-24-2022, 08:35 AM (This post was last modified: 03-24-2022, 08:42 AM by vtsteam.)
Well, I've done a fair amount of online reading about 4-jaw disassembly (Including a 2010 set of posts and photos somewhere from EdK), and it looks like it probably has the usual tight fitting forks (plugs).
The screw holes in the back of the forks are probably for a puller bolt, so I don't have to use a drift in the front of the chuck to knock them out. Convenient, actually.
But I still think it's going to be pretty hard to replace those forks and perfectly align the allen setscrew retainer threads.
The setscrews are commonly known as 'dutchman pins' that lock components together. I believe the plugs should be a snug slip-fit into the chuck body. Threading a screw into the hole and using a slide hammer should pop them right out if I'm not mistaken. A press fit would make lining up the forks around the chuck screws near impossible to do without them binding up the chuck screws. If nothing else you could always drill new holes on the other side of the plugs/chuck body and install new pins or screws after the plugs/forks are aligned properly in the chuck.
I had to replace the tail stock quill on my lathe and make up a new lead screw and quill nut for it. Same type of set-up basically.
