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  • #31
    I have a 12 by 36 Chinese lathe for about 5 years now and other than a slight learning curve compared to the better Colchester lathes at work it has been great. The price is good compared to some of the used lathes on the market and comes with most everything you need as mentioned by Joel. The drill chuck is crap but ok to start with. I machined alot of 316 and 303 stainless steel the first 2 years I had it and no problems. If you use the gearbox ensure you use lots of oil as it just has holes bored in the cast iron box with the shafts going through it and can seize up if it dries out and heats up(did it once to me). I am going to bore the holes out one day and put in proper bushings or bearings. I would also put a small bead of silicone around the bolt holes in the base before mounting the lathe or any coolant or oil will work its way down through them and on to the floor. I probably done just about all the things you can do with a lathe with this one and been quite happy with it. I would recommend it as a starter machine in any shop as the price is right and at 12 by 36 (plus it has a gap) it will take on most any job that comes up in a home shop. After that I would recommend a milling attachment and then carbides. If you plan on getting a Mill-Drill one day and get one with a MT3 instead of a R8 you can use tooling on both machines. Once you have the milling attachment or Mill-Drill you are on your way to making an endless supply of attachments for both. Good luck and enjoy making chips!!!

    Mike

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    • #32
      Hey, thanks guys for all the responses, even though I need to drill large holes in the stock I can easily leave about 1" over what I need and cut that off after I've made the hole. I think I've decided on the sherline 3.5" by 17" lathe. I'm only going to be lathing metal no more than 2", plus the sherline is nice and compact, has good reviews, and more importantly made by an american company. It is a little out of my price range but with any luck I'll have a drafting job with lockheed martin this summer. I know the drill chuck on the sherline is only 3/8" or 5/8", but you can get bits as large as 1" with that small of a shaft. I also have a drill press that I can use to make the larger holes if I have too, It is a large standup craftsman with nearly 1ft chuck movement, and the bed can be moved down or up like three feet.

      [This message has been edited by OREDIGGER! (edited 04-26-2004).]

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      • #33
        [QUOTE]Originally posted by OREDIGGER!:
        "I'm only going to be lathing metal no more than 2"

        Sure, that's what you say NOW.
        Location: North Central Texas

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        • #34
          Digger - Your missing part of the point. You WILL NOT be able to drill 1" holes with a small lathe. There's not enough power in the motors. You'll have to step drill or drill and bore. The boring bars that will fit the small machines and the small starting hole will not be a pleasure. It may take 64+ passes to get from 3/8" to 1" on those large deep holes.

          You're in for a big disapointment!

          If tolerance is no concern, do your drilling on your drill press.

          [This message has been edited by CCWKen (edited 04-26-2004).]

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          • #35
            Yep,Joel has it right,first its 2" then 4" then"hey!how do ya jack up a headstock?"

            I have heard it all before-"I just want a john boat I can take out on the weekends"-or-"I'm just building it so me and the old lady can go crusing"-or my personal favorite-"I only need the smaller oxy/acetylene burning rig" Before long you'll be like the rest of us,UTYAIC(UP-TO-YOUR-A**-IN-CHIPS!)
            I just need one more tool,just one!

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            • #36
              Uh, yeah, no more than two inches, that is the largest I would need it for. The current project I am working on is no more than 1.25". It's not a matter of bigger and better but what I actually NEED the lathe to do. If I need something larger there are three nice large lathes in my schools machine shop. Oh, and 64+ holes, not a problem, patience is one thing I have plenty of, and I already expected that I would need to drill in steps to get a whole that size. As far as power, not concerned there either, the sherline mill does only have a 1/3 hp motor. But for most of my purposes that is not a problem. I wouldn't mind having a 24 inch mill if I could find one around my price range. If harbor freight carries one then I might consider it. But I'm not JUST making this large peice, I am also making a host of smaller parts that would be much easier to make on a smaller lathe. The sherline lathe can also (with the attachment) make left hand, right hand, metric, and english threads which is a valuable feature I will need as well. After I drill this one large hole that is it, it may take one hour to drill/bore, but it will at least be done and done right.


              [This message has been edited by OREDIGGER! (edited 04-26-2004).]

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              • #37
                Oredigger, there is an old saying about lathes: You can make small parts on big lathes but you can't make big parts on small lathes. Since you have the room buy the largest lathe you can afford that is of reasonable quality, new or used.

                The first part I made on my SB9 over twenty years ago was a test of its accuracy. This is it.

                Free software for calculating bolt circles and similar: Click Here

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                • #38
                  But is it really that big of a part? I hear what you guys are saying and I am actually looking into the larger lathes, but if the largest peice of stock I'm going to be working with is 2", with the great majority of my work being done is around 1", why would their be a problem making a 1" hole in the stock? Of course this wouldn't be done in one pass, I would use progressively larger bits to build up to this diameter. I guess I'll actually explain exactly what I am doing, maybe that'll help. I recently designed a paintball gun, I play a lot and enjoy designing things so the two meshed together pretty well. This is not a spur of the moment design either, I've been working on it for about a month now gradually changing each peice to fit correctly. The through hole on the gun is .695", essentially .7", on the back end of the gun this needs to be enlarge to about 1" for a length of about 3.5", and on the front for about 2". Total length is about 6.5 to 7 inches. This is going to be cut in aluminum stock, either 6061 or 7075, T6 temper. This is not the only project I need the lathe for, just the largest. Why can I not do this on sherlines 3.5" x 17" lathe? Other than the spindle through hole is only about .5 inches, which can be worked around by adding length to the peice so I don't have to go all the way through. I don't want you guys to get frustrated with me because you think i'm stubborn, I just want to here a definate, "No that is impossible on that lathe and here is why" answer that is reasonable.

                  [This message has been edited by OREDIGGER! (edited 04-27-2004).]

                  [This message has been edited by OREDIGGER! (edited 04-27-2004).]

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                  • #39
                    Evan, by the way how do you make the cuts for the hex head? That is a very well done peice.

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                    • #40
                      The easiest way to make a hex head on a bolt is to use hexagonal stock. Beyond that, you probably want to index the stock via index head, spin indexer, collet block, rotary table, or what have you.

                      You can’t hang a 2â€‌ dia. 7â€‌ long piece of stock out of the chuck without a steady rest.

                      As for size, we assumed you were looking for a lathe to do the general-purpose type of work that the rest of us do, not for just one particular job. Buying a machine to make one paintball gun would make for one expensive gun. I wouldn’t spend any money to drill one hole if you could take it to school and drill it in 2 minutes on a full sized lathe. Ken makes the obvious point that if you only need a drill press to make your hole, you only need a drill press (which you have). If you really mean that you would be willing to increase a hole in 1/64â€‌ increments, you are indeed more patient then I.

                      I am a tad confused. Are you getting a Sherline mill, lathe or both?
                      You said that you wanted no less then 7" of swing at $1,000 or less for a mill and lathe. The Sherline meets neither criteria. Most of the smart folks here recommend 10-12â€‌ swing or better. It is not harder to make small pieces on a normal sized lathe that has more features (among other advantages). As Evan said, you can’t turn bigger pieces on a small lathe. Also, you will have to look hard for a lathe that doesn’t thread right out of the box. You may be asking more of the Sherline then it was built to deliver. It is a small and light machine, with very limited capabilities IMHO.

                      I could be wrong, but it sounds like it would be to your advantage to do some reading on the processes of machining. Read through the archives here, and look for some recommendations for books. It is best (and cheapest) to know how to accomplish a task before you start. There is a definite learning curve to safe and effective machining.

                      Good luck, let us know if we can help.
                      Location: North Central Texas

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                      • #41
                        I didn't. It was made from hex bar stock.

                        The reasons most of us are trying to persuade you to buy a larger lathe are several. First, although it may be technically possible to machine the parts on a small lathe that just meets the size specs you will be working at the limit of the lathes capability. That is never comfortable and make the chance of mistakes and problems very much higher. It also stresses the machine to its limits and that just isn't good for the machine. It also will take far longer to achieve the end result compared to a larger machine. That is not just a matter of time, either. The longer it takes to make a part the higher the chance that something will go wrong.

                        I'll illustrate by explaining how I would make a 8" deep 1" ID hole in Al on my SB9.

                        1: Chuck up part in the 6" four jaw and center. Right there I have a big advantage over the lightweight lathes. My 6" four jaw will hold that part without question. I note that the quality of the chucks matters a lot. My 3 jaw 5" and my 4 jaw 6" are both Bison chucks.

                        2: Face off end and pilot drill with center drill. We will ignore any possible OD machining.

                        3: Drill pilot hole with 1/4" X 8" aircraft bit at top rpm (657).

                        4: Switch to 1/2" Morse taper 2 drill bit, drill again at low rpm.

                        5: Switch to 7/8" MT2 bit and drill.

                        6: Setup 5/8" X 10" boring bar and bore hole to finish ID, probably 4 to 6 passes.


                        As I mentioned before, this job is near the limit of what the SB9 can do. One limit is the length of the drill bits. Another is the horsepower. Another is the distance between centers. Another is the rigidity of the carriage and toolpost to hold such a boring bar. Another is the RPMs available for drilling large holes (SLOW).

                        With a light lathe you might be able to complete the job also but you probably won't be able to drill over 1/2" due to horsepower and rpm requirements. Also you need at least 20" between centers to do it. As was mentioned before, having to bore from 1/2" out to 1" would be an exercise in extreme frustration as the boring bar would be so light and springy that if it could be made to work at all the cuts would have to be tiny. I have a lot of patience and at times take my SB to the limit but there are jobs that it could possibly do that I will not even try. It's a matter of recognizing when you are pushing the limits too hard. That is something that comes with experience.



                        [This message has been edited by Evan (edited 04-27-2004).]
                        Free software for calculating bolt circles and similar: Click Here

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                        • #42
                          Yeah, first, if you read my post, the paintball gun is just one of the projects I have. Second, as I have searched I have made the discovery that it will be near impossible for me to get a lathe and mill for my purposes under $1000. The 7" x 12" was a guess, buy I realized later that I would need more length, 7" swing is more than enough for my purposes. I plan on buying a mill, and sherline is more likely my choice for that. And I can get a steady rest for the sherline lathe, really what I need is a lathe that can handle this work, that comes with at least basic tooling, for under 1000, preferably around the 500 range. This basically knocks any lathe with less than 14" center to center distance out of my options. If I could find a southbend or atlas around here in that price range I'll jump on it. The other thing I like about the sherline is that you can get an attachment which allows you to make a very wide variety of threads, which I will need. Any thoughts, I also have time to figure this out. I need to wait till after I get a job and save the money.

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                          • #43
                            http://www.harborfreight.com/cpi/cta...emnumber=45861
                            I found this on harbor freights website, since there is a store rather close to me in Colo. Spgs. I imagine they have it. Would this do the job? 9" x 20" central machinery metal lathe, 3/4 hp motor. Here is my only concern, will it be able to make any thread pitch between 8-56 tpi that I need? I know you guys would probably prefer a southbend or atlas but unless I can find one for sale here in colorado springs I will have to use an alternative.

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                            • #44
                              The term "Great for precision work!" is a euphemism for "Light duty". It only does 12 different SAE threads and 12 metric so, no, it won't do any thread between 8 and 56 tpi. The entire machine only weighs 229lbs.

                              You would do better with something like this:

                              http://cgi.ebay.com/ws/eBayISAPI.dll...811249152&rd=1

                              or this:

                              http://cgi.ebay.com/ws/eBayISAPI.dll...811332442&rd=1

                              I'm not endorsing these sellers in any way but these are representative of what may be had to suit your requirements. (ignore the chuck key sitting in the chuck )

                              [This message has been edited by Evan (edited 04-27-2004).]
                              Free software for calculating bolt circles and similar: Click Here

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                              • #45
                                The first one only has a 1/3 hp motor, which is equivalent to the sherline model. The first one looks great except he doesn't give you center to center distance and shipping would be horrible. And you say "only weighs 229 lbs", how big of a machine do you guys want me to get before it takes up half of my two car garage? It is a 9" x 20" with a 3/4 hp motor, how is this "light duty" for the kind of work I am doing? Oh, yeah, it says it can only do 12 sae but what about what it says under headstock being 8-56 tpi?

                                [This message has been edited by OREDIGGER! (edited 04-27-2004).]

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