1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. PLEASE: Read the FORUM RULES BEFORE registering!

    Dismiss Notice

Atlas QC10 purchase (was Request value input on a QC10F TH42)

Discussion in 'ATLAS, CRAFTSMAN & AA' started by rzbill, Jun 15, 2017.

  1. rzbill

    rzbill United States The cheapest thing in an airplane is the pilot. Active Member

    Likes Received:
    73
    Trophy Points:
    18
    City:
    Leicester
    State:
    North Carolina

    -Return to Top-

    I'm fighting end float vs dial functionality. On the compound, the 3 hole plate is worn. It has a wear counterbore on the screw side and rough surface finish on the dial side. Dial needs to run on a sleeve so its not part of the gap setting stack up. I stoned and flipped the plate to temporarily deal with the wear counterbore. There is a non-orthogonality somewhere that tightens this area to non functional on 1/2 rotation unless end float is run very loose. I suspect the trimmed end of the Acme thread is not new geometry any more and needs some TLC.

    When I was cleaning the lathe some weeks ago I could not disassemble the cross slide dial area so I don't know the details of the internal problems there. I will need to try again.
     
    Last edited: Sep 10, 2017
  2. wa5cab

    wa5cab Downloads Moderator Staff Member H-M Supporter-Premium

    Likes Received:
    677
    Trophy Points:
    113
    Location:
    Spring Branch (Houston)
    City:
    Houston
    State:
    Texas

    -Return to Top-

    On the cross-slide dial area, in DOWNLOADS go to the Atlas lathe manuals Category (folder) and scroll down to and open Atlas Lathe 10F-Series Parts 10L-6 Rev6, Page 6. Part number 10F-46 Bearing (with Bushings) must be removed from the saddle in order to remove the screw and gear. It screws into the saddle and requires a pin spanner to remove. I would suggest a little Kroil and a day to soak as the first step. I would also suggest that one good solution to what you are trying to accomplish is to replace the existing parts with the equivalent ones off of a late 12". The dial is larger and easier to read, it runs on a steel shoulder bushing so is not affected by the end float adjustments, and the bearing has an external hex where the original on the 10" and early 12" is round with a pin spanner hole. I think that the friend who converted his cross feed dial also did the same thing on his compound dial, but I can't swear to it.
     
  3. rzbill

    rzbill United States The cheapest thing in an airplane is the pilot. Active Member

    Likes Received:
    73
    Trophy Points:
    18
    City:
    Leicester
    State:
    North Carolina

    -Return to Top-

    End float success on the compound. Down to 0.001". I confirmed tonight that while I had dealt with the worn 'counterbore' groove in the 3 hole plate (part 9-307) by flipping it over and presenting a pristine face to the boss on the screw, I had NOT looked closely at that boss on the screw. Sure enough, it was no longer square where it had been wearing into the plate. It had a taper and a radius from wear. A light touch with a cutter and it was square and sharp again. On reassembly, I was able to get the float down to ~.004" and still have the dial work. The dial was binding with too much friction against the 3- hole plate while traveling in one direction (Gibs are tight on purpose). I had some 1/32" teflon sheet in the shop. Made a quick washer to go between the dial and the 3-hole plate. I can make the end float zero now but it works a bit smoother at 0.001".
    Amazingly, the compound leadscrew and nut have an excellent fit. I can't feel any backlash by hand. I'd have to put my "last word" on it to measure if there is any.

    This bandaid will probably bide me over for a while. I only have time for stuff that really needs to be done.

    As you mentioned Robert, I do have about 0.015 backlash in the crossfeed system. Only a small portion is end float (little visual evidence of 'gapping" at the dial), most is leadscrew to nut fit I imagine. I saw the bit about cocking the nut. Hmm. Maybe later. I want to be careful about loading the cross feed gearing too much. The FEEDscrew gear male key is only a feather sticking up right now. It could shear any moment. I have the replacements. Thanks for the tips about the 10F-46 assembly.

    Since I'm talking about the cross feed, I found it was kinda' tough to disengage the crossfeed via the mushroom button on the apron in an accurate fashion. Sometimes it would resist movement and the cutter would go well past center. Yesterday , while playing, I realized it was very easy (and in my opinion safe for the machine) to simply disengage the QCGB to make the screw stop turning. I chose to use the left lever.(ABCDE) Afterwards the mushroom button was easy to move.
     
    Last edited: Sep 10, 2017
  4. rzbill

    rzbill United States The cheapest thing in an airplane is the pilot. Active Member

    Likes Received:
    73
    Trophy Points:
    18
    City:
    Leicester
    State:
    North Carolina

    -Return to Top-

    Continuing to work on the Atlas to take care of nuisance items.

    I bought some stuff at the 'lathe department' ;) at Lowes DIY store to make some adjustments possible without having to reach for a tool.
    Thumb screws for the crossfeed and compound dials. Had to trim the thumb screw on the compound to miss the adjacent screw heads. These will work until I have time and enough practice to make some knurled screws.

    Also bought a female 5/16-18 Tee Handle and glued a piece of threaded rod into it in order to replace the carriage lock screw. I'd rather have an "L" handle but they did not have those in the bins. Now that I see the pic, I see another place that needs a handle (the threading indicator bolt).

    20170917_083156.jpg 20170917_083310.jpg
     
    Last edited: Sep 19, 2017
    Ulma Doctor likes this.
  5. rzbill

    rzbill United States The cheapest thing in an airplane is the pilot. Active Member

    Likes Received:
    73
    Trophy Points:
    18
    City:
    Leicester
    State:
    North Carolina

    -Return to Top-

    2nd post for today. Did it this way to keep the images associated with the text.

    This is work on the small backgear and 4 sheave pulley on the spindle. The connection between these two parts is via cruciform mortise and tenon joint.
    After first listening to the din and then looking at the connection closely, I saw that the connection was worn badly. It appeared that the tenon width was 3/8" when new. Not anymore. First image shows the slop in the joint. I decided to take everything apart, narrow the male tenons on the pulley to 1/4" and cut a new set of mortises in the gear. Standard disassembly. Had to whack it with a deadblow hammer more than I wanted to. Cleaned and deburred the shaft. Cleaned and deburred other parts. Cleaned the spindle bearing housings. Found some grunge that I expected because every once in a while I would feel a 'hitch" in the spindle rotation. Thats gone now. Cut the pulley on the mill. It was a little fiddly to get the pulley "square" since the tenons were in bad shape. Gear was easier since rotational alignment was not critical.

    Took a little light hand file work on the pulley tenons to get everything to fit back together. Last pic shows the new tenon joints.

    Reassembled. Noise improvement. Last thing was to shim the back gear mount outwards a little. The big gear that mates to the small one on the spindle was ringing a lot. Adjusting the back gear handle 'outward' slightly made the noise go away. I took it as an indication the gears were meshed too close. Made a pair of 0.024 shims to replace the factory .010 shims. 0.024" was a wild guess and what I had. Appears to be close enough. Way quieter now. 20170916_175304.jpg 20170916_192020.jpg 20170916_203448.jpg 20170916_213920.jpg
     
    Last edited: Sep 19, 2017

Share This Page