Page 1 of 3 123 LastLast
Results 1 to 10 of 27

Thread: Using the lathe turret and tooling for the first time

  1. #1
    Join Date
    Jan 2004
    Location
    Independent principality of Sinquefieldia (formerly Missouri in the USA)
    Posts
    24,418

    Default Using the lathe turret and tooling for the first time

    So, I could not stand it, and before I wore myself out on outdoor work (so I would not want to lift the turret), I decided to give it a shot.

    Just used the new knee tool this time, to get a feel for how it was going to go. Started with a center drill in the holder, but changed over to a 3/16" drill, since I was not sure how well centered the turret was.

    The overall setup, with just a couple screws holding the turret gibs (lazy).



    Close up after a little cutting (center drill still in)



    After more cutting, 3/16" drill in place for drilling a quarter inch deep or so. The lines on the work are mostly because the cutter has essentially zero nose radius, and there is a little spring-back, mostly all in the work, I think.



    A chip. 0.1" or so DOC, chip thickness 0.015", actual cut probably 0.008 or a bit more, with the chip folded up a bit as it came off the tool.



    Seems to work well. Basically no chatter despite reasonably deep DOC, and aggressive feed. But, lest anyone should think the machine makes it easy, the thing will give you a workout. Feeding a drill and a cutter is not quick and easy the way it looks in the Youtube vids of CNC or automatics working.

    Makes me wish I had found a handwheel type, I think they have more leverage overall.

    Tooling shown here

    http://bbs.homeshopmachinist.net/thr...is-multiplying

    http://bbs.homeshopmachinist.net/thr...ight=knee+tool
    Last edited by J Tiers; 04-15-2017 at 06:10 PM.
    1601

    Keep eye on ball.
    Hashim Khan

  2. #2
    Join Date
    Jan 2004
    Location
    Independent principality of Sinquefieldia (formerly Missouri in the USA)
    Posts
    24,418

    Default

    I was going to load up more stations, and try doing a test part with drill and tap, etc. But a couple of the turret stations were jammed up with gunk.. so I have a delay while I remove the cam locks and clean the holes at each station. I thought I had done that before, but appaently not. It has also been sitting under the lathe bench, not the cleanest place in the shop.

    One station seems to be oversized, with a size in between 5/8 and 3/4. I realized I can just use that station for the stock stop, which can be made any size that I want, and can just be left in that position. So that is what I will do for the moment.

    More later when I finish cleaning and setting up for a test part.
    1601

    Keep eye on ball.
    Hashim Khan

  3. #3
    Join Date
    Jan 2003
    Posts
    3,556

    Default

    What brand is that turret? It doesn't look like ENCO which, believe it or not, was the manufacturer of most turrets factory supplied with small lathes back in the day.

    Does it have a lock down bolt in the center that can be used to manually secure the turret when using knee tools, etc that tend to put a rotating force on the turret?

  4. #4
    Join Date
    Jan 2004
    Location
    Independent principality of Sinquefieldia (formerly Missouri in the USA)
    Posts
    24,418

    Default

    Quote Originally Posted by DR View Post
    What brand is that turret? It doesn't look like ENCO which, believe it or not, was the manufacturer of most turrets factory supplied with small lathes back in the day.

    Does it have a lock down bolt in the center that can be used to manually secure the turret when using knee tools, etc that tend to put a rotating force on the turret?
    It is a Logan, made for this lathe, although not for this PARTICULAR lathe, I still have not determined if there is a significant error in center positioning due to it not being bored on this particular machine. Not a problem for some tools, but the center drill on the knee, and most box tools or releasing tap/die holders need their stations to be directly on-center.

    The turret locks in position at each station, so no manual stuff necessary.
    1601

    Keep eye on ball.
    Hashim Khan

  5. #5
    Join Date
    Apr 2017
    Location
    Kelowna BC
    Posts
    274

    Default

    Try putting a dial test indicator in your spindle and clock the bores in the turret.

  6. #6
    Join Date
    Jan 2004
    Location
    Independent principality of Sinquefieldia (formerly Missouri in the USA)
    Posts
    24,418

    Default

    Yes, just not done yet...... The initial test run showed the error if any to be small. But I have had to clean the turret holes and clamps up since, so......
    1601

    Keep eye on ball.
    Hashim Khan

  7. #7
    Join Date
    Jan 2003
    Posts
    3,556

    Default

    Quote Originally Posted by J Tiers View Post
    It is a Logan, made for this lathe, although not for this PARTICULAR lathe, I still have not determined if there is a significant error in center positioning due to it not being bored on this particular machine. Not a problem for some tools, but the center drill on the knee, and most box tools or releasing tap/die holders need their stations to be directly on-center.

    The turret locks in position at each station, so no manual stuff necessary.
    A good many turrets have the manual lock down feature even though they automatically lock. Cutting with a knee tool is an operation that tries to rotate the turret which can affect accuracy. This especially a problem with older turrets where there might be wear on the indexing pin or the hole it fits into. You would only lock down manually on knee type tools.

  8. #8
    Join Date
    Jan 2004
    Location
    Independent principality of Sinquefieldia (formerly Missouri in the USA)
    Posts
    24,418

    Default

    In any case, no specific manual lock that I am aware of. It's tight, and does not move. I doubt it got used much, but even if it had been loose, the pin and its bushings are replaceable parts.

    The knee tool cutter can be put at top, in whicn case a straight rotation affects the diameter to a lesser extent than on the side, where it is direct 1:1. The smaller the final diameter, the bigger the effect, however.
    Last edited by J Tiers; 04-17-2017 at 06:31 PM.
    1601

    Keep eye on ball.
    Hashim Khan

  9. #9
    Join Date
    Jan 2004
    Location
    Independent principality of Sinquefieldia (formerly Missouri in the USA)
    Posts
    24,418

    Default

    With regard to alignment of the turret, the best I can determine is that the original tool mount holes are about 0.003 "out" horizontally, and about 0.006" vertically (high).

    The two locations that were bored out larger seem to be somewhat more "out", but those need to be bored to 3/4", and sleeved, since they don't fit anything now. One is 0.651 diameter, the other about 0.673 diameter. Boring will put them on center, but I don't want to do it until the height of the others is correct.

    I do not know if I should try to get them better aligned now, or tolerate the error and wait until I work on the lathe bed (or possibly get another one). Any work on the bed, or bed replacement, will change the error. The bed is known to have about 0.004" wear now. If it were LOW, I could shim it up, as it is a clamp-on bed turret. High is a different issue, I am fresh out of those shims that have a negative thickness........and my suppliers are all out of stock.....

    The error, especially height, is about the amount of error that a well-used turret lathe would have, not crazy error, but just past the annoying point. The turret itself is not sloppy, and the error appears to be "parallel error", there is no apparent tilt of the holes relative to ram travel. I need to do a different setup to see if the ram travel itself is parallel to the bed.

    Drill and reamer holders will adjust to center. Box tools may adjust to center, depending on design. Knee tools will adjust to center. But any drills etc that are in the bore of tool shanks, like a drill in the knee tool, would need an offset bushing to be on center. That would be annoying to have to do.
    Last edited by J Tiers; 04-19-2017 at 10:10 AM.
    1601

    Keep eye on ball.
    Hashim Khan

  10. #10
    Join Date
    Apr 2017
    Location
    Kelowna BC
    Posts
    274

    Default

    I should mention that a lot of turret lathes, the turret has power feed, very handy with a knee tool or for drilling. My Herbert even had a ChipRupter lever that you could hit, to break chip..and it was momentary..not like disengaging feed on an engine lathe and waiting for it to go around a turn, and then slip back in.
    Also there was a large binding clamp in centre of the turret to lock down for stiffness in big or far reaching cut. They had optional large tool holders with a support bushing to top rear corner while in use, this slid over a large round bar extending out of the headstock casting..to increase stiffness and minimize flex.
    Imagine a multi tool arrangement 8 inches across, with say three cutters, then mounting electric motor bell ends in the spindle end...and machining 3 or more critical dimemsions in one cut.
    The turret binding clamps had an oil cap, that oil supply lubed the turret. There also was a 2 speed cross slide on the machine.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •