Chuck replacement, ..help!!

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PLEEEEAASE , I'm having a very hard time knowing how to order a new chuck, because I don't know the model/taper of the old chuck.  I already rolled the dice and ordered one that doesn't fit.  All it says on the old chuck is CAP 5/8 16m/m.  Can anybody tell my what model I should be shopping for?  The hole in the center of the chuck looks to be just a bit larger than 3/4", maybe 13/16".  I really would appreciate any help.  My dad gave me this old thing, not worth much $ but I really like it.  The old chuck is no good, has a wobble in it.  Thanks!
Reply:If you can use a caliper to accurately measure the top and bottom diameters of the quill, and the distance between them, those numbers can be looked up in Machinery's Handbook to determine which taper it has. On some drill presses, I believe the tapered male part actually is an adapter which fits into the quill proper and onto which the chuck presses. Maybe not yours though.Which one did you order? Jacobs is a commonly used taper for drill presses, but with an older import machine, I suppose it could be another.
Reply:Looks to be a JT (Jacobs Taper) for your drill press quill. There are a number of different JT tapers used on drill chucks of that size...3-4 in that size range...you'll need to compare measurements as OldIron2 stated. The hole, if you hadn't noticed already is tapered, so you will need the major and minor taper or minor taper and measure up exactly an inch and take a second reading. Post back with the measurements and I'll grab a copy of Mach. Handbook and look it up for you.Also, as OldIron2 stated, your male taper may or may not be integral to the quill. Easy way of telling is to extend the quill downward full length and see if there are two long slots on the quill. If they are there, your mount/adapter is removable with a taper drift. Depending upon whether or not you need to replace the taper due to galling, this may be advantageous for you. BTW, that taper will be a MT (Morse Taper)...probably either a MT2 or MT3.Personaly, if the JT taper matches, or the taper in the quill is removable, I'd hit eBay and look for a good used Jacobs Super Chuck in either a size 14N...1/2" max or size 16N...5/8" max. They have hardened jaws so they grip better than a standard chuck, ball bearings so the chuck is easier to tighten down and built to a bit better tolerance for run-out than the standard Jacobs brand chuck.Lincoln PrecisionTig 275Miller 251Miller DialArc 250Bridgeport millHossfeld bender & diesLogan shaperJet 14 X 40 latheSouth Bend 9" 'C'Hypertherm 900Ellis 3000 band saw21"Royersford ExcelsiorTwo shops, still too many tools.
Reply:Chucks are often (usually) marked with the machine taper that they have--to save guesswork.What is all the verbage stamped on that chuck OD?Blackbird
Reply:Only "CAP 5/8 16m/m" is stamped on the chuck, that's it.  The new chuck I rolled the dice on is "Shop Fox" JT33, the tapered hole is way too small on the new chuck, I shouldn't have guessed like that.  Co's don't answer my emails then I finally found this forum.  I took off the pulley and dropped the whole quill/unit to clean it several days ago, there is no slot to use a drift but I noticed when I knocked the chuck off that the arbor(?) was starting to come out until the chuck finally dropped off of it, I don't know what was going on there, has to be separate from the quill unless there is something else I don't know about inside there.  I knocked in back up with a rubber hammer.  This is my first drill press, hope I'm using the right terminology.  The tapered end is VERY smooth when it rotates.  I put my fingers on it while it's spinning and I feel no dings, no wobble or vibration.  I cleaned and greased every moving part, I took the motor apart and repacked the bearings, but it's no good without a chuck.  I really appreciate the help, I will measure the major and minor taper end within an inch and report back.  btw, what are the two slots on the base for?, guess I could use the search function for more info.
Reply:You have two options:1) Attempt to return the new chuck JT33 for one to fit the arbor in the drill (you will need to make measurements with calipers or a micrometer, one of us can look it up if you don't have the book)2) Order an arbor to fit the drill.  It *should* be a 3MT arbor (on the other side of the JT33).  You will need to knock it out of the drill.  This is done from the top of the drill.  The spindle should be hollow and you can use a piece of round stock to *tap* it out.The new arbor may be cheaper than trying to return the chuck for the right size, but you will have to make the call.
Reply:X2 on what Fegenbush said, most drill presses have a MT3, use your new chuck and get an arbor to match.LarryMiller XMT 304 CC/CVSyncrowave 180 SDLincoln PowerMig 255XTTermalDynamics 52Lincoln 305GComlpete machine shop to back it up
Reply:I just bought a Jacobs JT33-MT3 arbor the other day from enco.  $18.33 PN890-9536.  www.use-enco.comDynasty200DX w/coolmate1MM210MM VintageESAB miniarc161ltsLincoln AC225Victor O/A, Smith AW1ACutmaster 81IR 2475N7.5FPRage3Jancy USA1019" SBAEAD-200LE
Reply:OK thank you very much for all the info and suggestions, I may just get another arbor.  But I may try to return the chuck and get the right size for the existing arbor.  I measured the original arbor taper.  At the bottom, it's 3/4", an inch up it is 13/16".  I used a good digital caliper.  Does anybody know what chuck model those measurements correspond to?  I plan to knock the old arbor out and post a pic of it to make sure it's not something out of the norm.
Reply:Originally Posted by petersiiOK thank you very much for all the info and suggestions, I may just get another arbor.  But I may try to return the chuck and get the right size for the existing arbor.  I measured the original arbor taper.  At the bottom, it's 3/4", an inch up it is 13/16".  I used a good digital caliper.  Does anybody know what chuck model those measurements correspond to?  I plan to knock the old arbor out and post a pic of it to make sure it's not something out of the norm.
Reply:I don't want to add confusion , but my Sears drill press (1/2 HP) is a MT #2 in the quill....as said, ya need some acc. numbers.........
Reply:Originally Posted by petersiiOK thank you very much for all the info and suggestions, I may just get another arbor.  But I may try to return the chuck and get the right size for the existing arbor.  I measured the original arbor taper.  At the bottom, it's 3/4", an inch up it is 13/16".  I used a good digital caliper.  Does anybody know what chuck model those measurements correspond to?  I plan to knock the old arbor out and post a pic of it to make sure it's not something out of the norm.
Reply:Hmmm, OK, thanks a lot!  Good sites for me to look at too, thanks. There is a forum I go to where I have several thousands of posts so I know how it goes when people frequent a forum and see the same posts over and over and over again.  So really, I do appreciate the patience.  Sometimes it's as though some of the more experienced people feel like they are talking to the same person over and over and over again on forums, having to repeat themselves, not realizing that there is a rollover.  To me it is like new students entering a class that the same teacher has taught for 20 years.  It's disappointing to see some people get so caught up in what they know, and having repeated the same things so many times, that they start calling other people "idiots".  Instead of me comparing and getting frustrated, I either help or don't respond at all, so I'm glad to see the helpful attitude here.  I measured in "fractional inch" mode to 1/64" of an inch, I'll change modes and measure again.  But I remember measuring in 1000s also and it was something like .7575 and .8110, ...lol I just looked at the post-it I wrote on and that was it.  It's only coincidence that the readings turned out to sound rounded out.  I think you got it Dunemetal.  About the arbor, I'm not sure about it.  I plan to drop the quill again and take pics.  imo, I think the arbor is going to be dislodged by knocking on the splined end of the spindle with a rubber hammer when I remove the quill, there is a nut to remove on the spindle just above the top ball bearing on the quill I took off before.  Well maybe it will be something somebody else may need to refer to later.  lol, I'll get it right sooner or later with this help, thanks a lot!
Reply:Oldiron2's hunch was right, what would be the arbor is integral to the spindle.  Here are the pics.  I'm sure it's going to take a Jacobs #3 now.  Even though I'm getting close to .7575 on the small end, and moving up 1.22" I'm getting .82**(can't remember exactly right now.  So I just took the taper diff between the listed specs between the large and small taper(.7461 and .8110) at 1.22", even though the small end is a little larger than the listed specs, the taper diff between the high and low is the same at 1.22".  Also earlier I was going up an 1" instead of 1.22".  I'm only getting a taper error of + - .0020 and I get that with trying to measure the same area, kind of hard for me to go up exactly 1.22.  Thanks a lot everybody, I learned a lot about it.
Reply:Originally Posted by petersiiHmmm, OK, thanks a lot!  Good sites for me to look at too, thanks. There is a forum I go to where I have several thousands of posts so I know how it goes when people frequent a forum and see the same posts over and over and over again.  So really, I do appreciate the patience.  Sometimes it's as though some of the more experienced people feel like they are talking to the same person over and over and over again on forums, having to repeat themselves, not realizing that there is a rollover.  To me it is like new students entering a class that the same teacher has taught for 20 years.  It's disappointing to see some people get so caught up in what they know, and having repeated the same things so many times, that they start calling other people "idiots".  Instead of me comparing and getting frustrated, I either help or don't respond at all, so I'm glad to see the helpful attitude here.  I measured in "fractional inch" mode to 1/64" of an inch, I'll change modes and measure again.  But I remember measuring in 1000s also and it was something like .7575 and .8110, ...lol I just looked at the post-it I wrote on and that was it.  It's only coincidence that the readings turned out to sound rounded out.  I think you got it Dunemetal.  About the arbor, I'm not sure about it.  I plan to drop the quill again and take pics.  imo, I think the arbor is going to be dislodged by knocking on the splined end of the spindle with a rubber hammer when I remove the quill, there is a nut to remove on the spindle just above the top ball bearing on the quill I took off before.  Well maybe it will be something somebody else may need to refer to later.  lol, I'll get it right sooner or later with this help, thanks a lot!
Reply:Yeah I understand, as I said, I appreciate it the attitude.  Now I'm on the search for good chuck, don't want to get a cheapy, some high $ of course.  The slightly large measurement on the small end was throwing me off at first but I think it was originally not a high $ machine, some info I came across said it was prob made in Taiwan.
Reply:Good chuck? Try a used Jacobs Super Chuck off eBay. Generally, the pictures in the auction body will give you a good feel of the condition of those chucks...I haven't come across a bad one yet after buying 6-7 that way. Superior run-out to most other chucks with the possible exception of Albrecht brand chucks. Do yourself a favor and pop the top cover and check the drive belts to see if they have been replaced. If they are still of Asian manufacture, swap them out with better quality belts. Do a search here or on one of the machinist boards on the proper care and procedure for installing a new chuck to your mount. Short version...clean both the chuck and the mount taper with acetone or other cleaner to remove every last bit of grease and grime, leave the mount taper quill out in the cold shop and heat the chuck with a hair dryer or heat gun so there is some expansion, slap together and whack with a rubber mallet and you shouldn't have a loose bond between the chuck and taper that can ruin both if they spin.Lincoln PrecisionTig 275Miller 251Miller DialArc 250Bridgeport millHossfeld bender & diesLogan shaperJet 14 X 40 latheSouth Bend 9" 'C'Hypertherm 900Ellis 3000 band saw21"Royersford ExcelsiorTwo shops, still too many tools.
Reply:I can't believe the price of some of those new chucks but I believe in getting stuff that lasts instead of buying crap.  I bought a good one, man I'm embarrassed to say what I paid for it.  Should last a life time though, the rest of mine at least.  I found a lot of info on chuck removal and installation, that's how I originally got it off.  A lot of diff opinions about installations, use a hammer, don't use a hammer, ...use the press, don't use the press, didn't come across the heat thing though, I may do that, a lot of vids on Youtube.  The belt thing is frustrating.  I took the old belt to a auto store and he thought he matched it up, looked pretty good but it's too small.  I can get it on but it's too tight with the motor adjusted as short as it will go.  Then I ordered an A-43, "what's printed on the old belt".  It turned out to be too big with the motor all the way out so I'm going to keep looking around, thanks.
Reply:Nothing wrong with spending money on a good chuck. I bought a Harbor Freight version back in the early '80s, looks very similar to yours except for the table. Suffered with that pain in the *** machine for years thinking to myself, "I should have saved my money and bought a decent drill press!!" Finally, a few years back the POS chuck that came with it gave up the ghost at ever being able to hold a drill bit tightly and I swapped it for a Super Chuck. Wonder of wonders...the darned drill press morphed into a decent machine as soon as I tried drilling the next hole. I should have unpacked that drill press, removed the cheap chuck and tossed it in the trash the first day I had it...'cause it never worked well.Lincoln PrecisionTig 275Miller 251Miller DialArc 250Bridgeport millHossfeld bender & diesLogan shaperJet 14 X 40 latheSouth Bend 9" 'C'Hypertherm 900Ellis 3000 band saw21"Royersford ExcelsiorTwo shops, still too many tools.
Reply:Well I don't know what might happen to the press later, but I think the chuck will stay with me and be an heirloom!  I'll prob play with it for a while before I mount it ...hey that didn't sound right.  Thanks again everybody, the numbers were confusing to me at first, I learned a lot.