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  1. #41
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    Those pictures suck too....sorry about that...I’ll get some more

    Here is the gear and threading plate picture, hope it turns out better...

    bef51a39-1a22-4f86-86af-640990e60907.jpg

  2. #42
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    The video is neat....one thing I notice is he does utilize the foot brake on the lathe to keep from running into his work and the thread dial not traveling too far, where as I have to let it coast as I do not have a foot brake either...

    I will attempt this method along with a few other suggestions this weekend when I get some time in the shop.

    I greatly appreciate all of the advice and help guys!! THANKS

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    Good luck with experimenting. Spinning down quick, like the video, helps ward off impatience - and it does keep the thread dial from spinning very far from 0, but that too should only be bonus assurance. I'm sure there is a screw scenario to prove me wrong, but my math says it'd have to be a strange one to not have 0 still work out even after some random number of turns.


    Noting process: Your lathe doesn't spin down quick, and you get the most heebie jeebies at the end, so I'd go back to my prior suggestion - opposite the video. Bring the thread dial to 0 shortly to the right of engaging the part, and set a stop or 0 a dial there. Now with a visual stop point on your part - and I really like the idea of a rotation mark on the chuck mentioned earlier too - spin it up and never turn off the spindle but to inspect the thread. One hand on the cross slide, one on the half nut lever, engage both when at the right stop/0 & the thread dial hits "0," disengage both at your finish marks.

    Easy peazy! I have to try that piece of tape on the chuck myself this weekend.

    Of course, should you keep it, it'd be very tempting to install a VFD with a fast stop cycle/resistor even before a DRO. Variable speeds, quick stop, and DRO should make it quite user friendly!

    Edit: Had a brief moment in shop last night, so tried engagement points at a stopped location; 4tpi screw & 4" dial travel/turn - hit 16points on the dial as would be expected. Unfortunately it happened I was at 12tpi, so the spindle was right too. I should have set a fractional thread - to more closely mimic the standard on metric scenario here, and then probably would have had the spindle right only at 1 number.
    Last edited by OldParts; 03-15-2019 at 08:28 AM. Reason: Noted results

  4. #44
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    Quote Originally Posted by coontz74 View Post
    It is indeed very well built, heavy, super smooth...I have taken a couple classes and know just enough to be a tinkerer. I’ve chambered a couple of BR barrels and practiced on “quite a few”...

    The threading is what has me on edge every time. Having to leave the half nuts engaged in order to thread 1-18 or 1-16 is nerve racking to me and no I don’t play the radio or have people in the shop...before someone asks. It’s just a tense time because I only keep the tenon out of the jaws so I have very little room for error.

    I do cut a thread relief, keep one hand on the cross slide and one on the off switch. When I reach the thread relief, I turn the switch off and crank out the cross slide to keep the tool from hitting the chuck and let coast to a stop.

    By doing that, I thread at a relatively slow speed which works out but feel the threads would finish better at a higher speed??? Maybe, maybe not??

    This also wouldn’t be an issue if I let the barrel stick out farther from the chuck but as I said, I’m very new....

    I run the lathe on a rotary converter with a 10hp motor for the 3 phase. From what I’ve read, I “could” go straight to reverse...the 3 phase would “soak up” the abruptness of going from forward straight to reverse?? Maybe, maybe not??

    Anyway, sorry for the long post. Hope I didn’t bore you, but short answer on why I want to sell is the threading process with engaged half nuts...

    I can’t thank you enough for the questions and critique.
    Cut the threads from spindle > tailstock

    Here's a good video on how to do it.

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  6. #45
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    Great video of turning in reverse!

    I wish he would have been controlling cut depth from the compound though - I'm guessing he prefers not too, as feeding to the tailstock, the compound would need to point that direction, so he might be running into limitations of chuck clearance with the compound. Regardless, somebody could probably point out there is a feed/speed combination that can be found successful, but I have had material cutter combinations that just were not cooperating with me unless feeding to a chip load in one direction - the 29 to 30 degree compound setting often suggested on a 60 degree thread.

    A classic example in my memory was getting some nice threads on cast despite being too lazy to turn the compound; my next part was a somewhat unknown steel - probably like a 414something with some cold work - that chipped the cutter a couple turns in. Every time for three attempts! When I changed the insert, I turned 29.5 on the compound. Cut nice, no more cutter damage.

  7. #46
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    Regarding my optimism in post 43 - internet advice is worth no more than you paid for it.

    With a fraction thread, a 0 mark on my chuck only came out to exactly 1 dial mark. As much as I'd like to think that it could still work, that ratio to metric probably makes even 1 mark optimistic. Worth trying; the threads you're running could happen to work out, you could even do the calculations, but trying a couple thread settings while comparing the spindle to the dial seems quicker.

    Else, it might be back to as demonstrated in the earlier video, where the half nut is never disengaged more than a turn of the dial and re-engaged upon being reversed back to the exact spot it left. That VFD with stop does start to sound nice then!

    Good luck!

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    I had a couple minutes in the shop when I got home this evening.

    I can confirm a couple of things:

    -My lathe does not have the clutch that allows the carriage to be reversed while the spindle is running forward.

    -I took a few dry runs with the technique in the video. No material in the chuck, just running thru the steps.
    It seems at @ 160-185 rpm, my 3 numbered dial will not even reach the second number while coasting to a stop after disengaging the half nut and flipping power switch at same time. Then re-engage when the number comes back from reverse.
    Really seemed to develop a feel for that. Tomorrow I will try and cut some threads on some scrap I have laying around. Possibilities are there...we’ll see...

    I started looking at DRO’s and reading about different models here and other forums....the list of opinions is quite long and won’t debate that in this thread, but feel I can put a decent DRO for $1000 or less...more to research before deciding.

    I wish someone could see the value I see in the lathe because I would still like to sell and acquire something a little larger(40” + bed) “with” an inch lead screw.

    I’ve had a few inquiries, but most grow quiet when they realize it is a metric machine.

    Reading all of your responses, and those from others, have been a real eye opener on what is possible and I could never repay you all but I sincerely appreciate everything.

    I will update after this weekend. Thanks again.

  9. #48
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    Yea not much call for a small Metric lathe near Atlanta. I would love it myself but like others I cant afford it, not necessary to my business and it would be just a convenience. Being metric isnt an issue as most everything I do is metric. It is a great little lathe in great condition, I hope you get what you want for it, it is worth it.

    Charles

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    Quote Originally Posted by CBlair View Post
    Yea not much call for a small Metric lathe near Atlanta. I would love it myself but like others I cant afford it, not necessary to my business and it would be just a convenience. Being metric isnt an issue as most everything I do is metric. It is a great little lathe in great condition, I hope you get what you want for it, it is worth it.

    Charles
    Charles,

    I appreciate your reply from a local guy, nonetheless. I would be interested in trading as well for something along the lines of a 16x40 with an inch lead screw if you or anyone you know would be so inclined.

    Also, glad to hear your thoughts on the asking price. Maybe I could still have some hope of a transaction??

    Thanks again

  11. #50
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    Quote Originally Posted by coontz74 View Post
    It is indeed very well built, heavy, super smooth...I have taken a couple classes and know just enough to be a tinkerer. I’ve chambered a couple of BR barrels and practiced on “quite a few”...

    The threading is what has me on edge every time. Having to leave the half nuts engaged in order to thread 1-18 or 1-16 is nerve racking to me and no I don’t play the radio or have people in the shop...before someone asks. It’s just a tense time because I only keep the tenon out of the jaws so I have very little room for error.

    I do cut a thread relief, keep one hand on the cross slide and one on the off switch. When I reach the thread relief, I turn the switch off and crank out the cross slide to keep the tool from hitting the chuck and let coast to a stop.

    By doing that, I thread at a relatively slow speed which works out but feel the threads would finish better at a higher speed??? Maybe, maybe not??

    This also wouldn’t be an issue if I let the barrel stick out farther from the chuck but as I said, I’m very new....

    I run the lathe on a rotary converter with a 10hp motor for the 3 phase. From what I’ve read, I “could” go straight to reverse...the 3 phase would “soak up” the abruptness of going from forward straight to reverse?? Maybe, maybe not??

    Anyway, sorry for the long post. Hope I didn’t bore you, but short answer on why I want to sell is the threading process with engaged half nuts...

    I can’t thank you enough for the questions and critique.
    I will address this post.

    There are many variables such as does the lathe have a metric lead screw, but since it cuts inch threads and has a thread dial, this will apply.

    The thread dial can be used this way.

    Start the machine, engage the half nuts on the #1 mark on the thread dial.

    At the end of the thread, disengage the half nuts.... and about the same time stop the spindle.

    Return the carriage/tool to the start of the thread manually.

    Now, run the machine in reverse until #1 on the thread dial returns, so as you can engage it again when you start the machine for the next pass.

    This is still very much like leaving the half nuts engaged, you still have to reverse the machine to the point you started at. Its very hard to loose your mark, as often thread dials make a full turn in 4" of travel, so if its a long thread it may take more then a turn on the dial when running it back in reverse.
    With that you can thread up to a shoulder.
    I found this method works well on machines that are hard to stop. I would suggest a little practice first.

    2 left hand threads on a saw arbor

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    donie,

    Thank you for the reply. The threads I generally cut are not very long in length and this is the method I was practicing yesterday evening that I mentioned above.

    It does seem to work quite well and think I prefer trying this on a part vs what I was doing before.

    It seems there are a few options for inch threading and I’m glad I’m here to take in all you experts have to offer.

    Thanks again.

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    I am glad that method was mentioned.

    The machine you have looks like its in good condition, it would have the value you were first thinking to the right shop. The problem you will be facing finding a replacement in good condition at reasonable cost.
    The Hardinge and Monarch inch metric models, often cost 7 to 10k more on the used market for the extra capability to cut metric threads, finding a quality metric only machine for a bit less, would be a good option.
    Anyway, I would not give that machine away.

    integrated dual system with ease of use

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    Quote Originally Posted by donie View Post
    I am glad that method was mentioned.

    The machine you have looks like its in good condition, it would have the value you were first thinking to the right shop. The problem you will be facing finding a replacement in good condition at reasonable cost.
    The Hardinge and Monarch inch metric models, often cost 7 to 10k more on the used market for the extra capability to cut metric threads, finding a quality metric only machine for a bit less, would be a good option.
    Anyway, I would not give that machine away.

    integrated dual system with ease of use
    That’s a nice looking lathe!!

    I agree, my lathe is in good shape given its age, I think it is worth what I’m asking to right place...that right shop hasn’t come along yet though.

    I have found a couple different lathes for its replacement but are about 12 hrs from here and can be had $6000-$7000, so your estimate is pretty close.

    Even after seemingly finding multiple options for threading, I would still like a bigger lathe.

    I had a 17x67 before this one and sometimes wish I still had it...

    I am going to still keep it up for sale. I did drop the price a few hundred dollars and updated the CL ad. Maybe someone will come along who will appreciate this little metric machine as much as I do.

    Thank you for all the info and encouragement.

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    Quote Originally Posted by CBlair View Post
    Yea not much call for a small Metric lathe near Atlanta. I would love it myself but like others I cant afford it, not necessary to my business and it would be just a convenience. Being metric isnt an issue as most everything I do is metric. It is a great little lathe in great condition, I hope you get what you want for it, it is worth it.

    Charles
    Agreed. I am wishing I had money and space.

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    Quote Originally Posted by OldParts View Post
    Great video of turning in reverse!

    I wish he would have been controlling cut depth from the compound though - I'm guessing he prefers not too, as feeding to the tailstock, the compound would need to point that direction, so he might be running into limitations of chuck clearance with the compound. Regardless, somebody could probably point out there is a feed/speed combination that can be found successful, but I have had material cutter combinations that just were not cooperating with me unless feeding to a chip load in one direction - the 29 to 30 degree compound setting often suggested on a 60 degree thread.

    A classic example in my memory was getting some nice threads on cast despite being too lazy to turn the compound; my next part was a somewhat unknown steel - probably like a 414something with some cold work - that chipped the cutter a couple turns in. Every time for three attempts! When I changed the insert, I turned 29.5 on the compound. Cut nice, no more cutter damage.
    I know this is controversial, but I no longer bother with the compound when threading. Joe is the guy that convinced me to try it. I've cut threads using the compound and then again using the cross slide. I could not tell the difference in the threads, even under magnification. The only problem with cutting threads with the cross slide vs. the compound is that lighter cuts have to be taken once the depth gets to a certain point or chatter might rear it's ugly head because the tool is cutting on both sides of the V. This is mostly a problem with low TPI threads and very tough metals.

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    Understand you want a machine with more capacity, but as far as threading goes, you can add a foot brake to stop the spindle more quickly. Pretty easy, and less expense than a Vfd, and it’s an added safety feature too.
    Really kind of surprising more folk don’t add one!

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    Quote Originally Posted by cyanidekid View Post
    Understand you want a machine with more capacity, but as far as threading goes, you can add a foot brake to stop the spindle more quickly. Pretty easy, and less expense than a Vfd, and it’s an added safety feature too.
    Really kind of surprising more folk don’t add one!
    Do you have more details or a link? I don't think he has a brake, so I'm not picturing how to easily add one without VFD or similar. I'm also a bit intrigued: I have a mechanical clutch and mechanical brake - a linkage off the lever would do it, though I haven't been tempted enough. On my lathe with only 30" between centers and a lever at the head & at the apron, foot stop would be more of the added safety and maybe occasional convenience for me.

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    Quote Originally Posted by cyanidekid View Post
    Understand you want a machine with more capacity, but as far as threading goes, you can add a foot brake to stop the spindle more quickly. Pretty easy, and less expense than a Vfd, and it’s an added safety feature too.
    Really kind of surprising more folk don’t add one!

    I echo the above comment...I’d like to hear what kind of setup you have in mind?
    I do not have a brake now, but would consider options. I still would like to sell just for bed length at this point but simplicity as well.

    Thank you for your reply.

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    Quote Originally Posted by SamH View Post
    Agreed. I am wishing I had money and space.

    You can always PM me an offer...never know, you may own it.

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    Quote Originally Posted by coontz74 View Post
    You can always PM me an offer...never know, you may own it.
    lol, don't do that to me. I still need to get some space. Hoping to have the new shop built in the next 6 months.

    That being said, I don't think you are too far from me, wouldn't mind coming to take a look at it.


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