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View Full Version : Jet 9" x 20" lathe



Popeye
06-08-2004, 05:19 PM
Does anybody have experience with threading metal, on a "Jet" 9 x 20 lathe?? I haven't bought one yet. Just checking out the waters before I buy. Any other thoughts on this machine are welcome too. Thanks

Mike W
06-08-2004, 05:51 PM
I have a 10 by 24. I have done Acme threads on it. Mine was made by Lantaine in Taiwon in the late 70's. I can't find any info on them.

jfsmith
06-08-2004, 06:05 PM
I have a Jet 13 x 40 lathe and just did some threading on it, 1" x 8 TPI, it was near perfect.

Hope this helps,

Jerry

mbensema
06-08-2004, 06:13 PM
I have the Jet 9x20, it's an ok lathe, but needs some improvements like all the 9x20s.

I work mainly in metric, so have only done a few standard threads with it. What exactly are you interested in knowing about the threading?

If you do get this lathe, there are several modifications you should plan on doing. You can see them here, www.bedair.org. (http://www.bedair.org.) The cross slide bracket is lacking and should be the first project you do.

If you can swing it and are planning on buying a new lathe, I would recommend getting the 12x24 instead. It is a much better lathe then the 9x20 and has features the 9x20 doesn't, such as power crossfeed and reverse feeding direction. The lowest speed of the 9x20 is also 130 rpm, so for threading that can cause problems.

Mike

Carl
06-09-2004, 12:46 AM
I'm posting a couple of pictures of threading projects I did on my 9x20 Grizzly (the same lathe painted a different color)They were done using the 130 rpm speed and the threading dial. Course threads on large diameters cause the slip clutch included on this model to slip. Disabling the slip clutch may cure this problem to some degree, but I haven't tried that yet. I have cut a 7/8-9tpi but it took some time and patience. The thread in the first photo is 7/8-18 and was no problem at all to cut. The second photo is of a 3/8 shouldered stud made from a 1/2 inch bolt, 3/8 threads on each end were single point cut.


http://img11.photobucket.com/albums/v35/lathefan/1e074747.jpg

http://img11.photobucket.com/albums/v35/lathefan/6c6398a2.jpg




[This message has been edited by Carl (edited 06-09-2004).]

Popeye
06-09-2004, 09:34 AM
Thanks for all the input on the 9 x 20. I picked threading for the question about the machine, because that alone will answer alot of questions about the ease of use and rigidity of the machine.
I enjoyed the link to Steve Bedair's site. He's done alot of improvements on this machine. And Carl, thanks for the pics too.
Maybe this machine isn't fit for me tho. I'd rather get something I didn't need to improve on to use. I'm really used to using a Hardinge Toolroom lathe, and that will spoil you big time.
I've seen a Prazi 10 x 19 on the market. It's about 6 times the price of the 9 x 20 tho. Might just be worth the difference.
I have space and weight limitations to worry about, so that's why I don't have a Hardinge HLV-H sitting in my shop.
I'm keeping my eye out for a lathe to fit the needs and the pocket too. Thanks all.

eperkins
06-09-2004, 10:23 AM
These 9X20's seem to have a couple of major drawbacks. First, the low end speed is really to fast for threading. I think it is about 130 rpm. The lathe is not back geared so you can't get any slower. Also these machines lack any kind of tumber reverse like a typical back geared American lathe. You may not think this is necessary, but try cutting left hand threads without it. For my money on a Chicom lathe, I would get a Grizzly or Jet 12X36 back geared belt driven model, or a used 9" South Bend or 10" Logan. A lot more lathe, and you probably won't have to upgrade later.

Perk in Cincinnati

MickeyD
06-09-2004, 07:54 PM
I have had a Jet 9x20 for a little while, and for what it is, it's not bad. Got mine used from a retiring gunsmith who did very nice work with it. It is a light weight bench top lathe that is capable of doing nice work if you do not push it too hard. If I was going to buy a new 9x20 I think that I would look at the Grizzly or HF because there is a premium on the price of the Jet that I am not sure is worthwhile, plus while is not the best color for something that is going to stay oily.

If you decide to get a 9x20, do not waste your money on the factory stand, it is the right height for a child but a realy pita, or pain in the back for anyone over five foot tall. Put it on a sturdy bench and make a pan out of a couple of cookie sheets welded together. Gets it up so you can see and keeps the oil from running everywhere.

gundog
06-10-2004, 09:15 PM
I bought a new Harbor Freight 9x20 lathe, before I put it in service a friend had a SB 10K in excellent shape for sale, so I bought the SB and sent the HF 9x20 back and have not regretted it. The only problem I have had was with the belt and I have replaced it and no more problems. I had paid $700 for the HF and paid $1000 for the SB. I have seen other SB's on ebay priced similar.