Thanks Thanks:  0
Likes Likes:  0
Needs Pictures Needs Pictures:  0
Page 3 of 3 FirstFirst 123
Results 31 to 40 of 40
  1. #31
    Join Date
    May 2006
    Location
    Canley Heights, NSW
    Age
    67
    Posts
    529

    Default

    Very nice work.

  2. #32
    Join Date
    May 2006
    Location
    Brisbane
    Age
    80
    Posts
    37

    Default

    Quote Originally Posted by SC_RUFCTR View Post
    That's an impressive lathe!
    ...and right next to it is an even bigger, older one. It's too big to be of any practical use in our workshop and it ain't going anywhere because it was placed on the slab before the shed was built around it. The bed is 3.5 metres long and the chuck is 450mm diameter (with plenty of room for a bigger one).

    Goodness knows where it came from or who made it. No branding that I can see. When I've finished getting the MARS in working condition I might give the old one a coat of paint to make it look like it works.
    Attached Images Attached Images
    Cheers,

    J

    ....

    Data isn't Information, Information isn't Knowledge, and Knowledge isn't Wisdom!

  3. #33
    Join Date
    May 2006
    Location
    Brisbane
    Age
    80
    Posts
    37

    Default

    No photos, but a major project over recent weeks has been to fully dismantle the gearbox on the front of the carriage, clean out all the swarf, refurbish various spring-loaded detent balls and replace some more missing gear teeth Now fully reassembled and everything turning smoothly.

    Today's project was to remove the thread cutting gearbox and clean that out. It proved to be impossible to access two of the mounting bolts without raising the lathe bed. Fortunately we have an engine hoist that can handle the weight but took the precaution of removing the motor first to help keep it reasonably balanced.

    Underneath the bed was a 60 year accumulation of swarf so now is an opportunity to clean all that out. Inside the gearbox was also full of swarf but fortunately all the gear teeth are in good nick so it's just a matter of giving it a good clean and again refurbishing various spring-loaded detent balls.

    Shouldn't be too long now before we can start reassembling the beast,
    Cheers,

    J

    ....

    Data isn't Information, Information isn't Knowledge, and Knowledge isn't Wisdom!

  4. #34
    Join Date
    Jan 2010
    Location
    Perth
    Posts
    119

    Default

    Well done - it's amazing what you can find when you do an archeological 'dig' under the bedways. Looking forward to next installments - and of course the pics when you have a moment. Mark

  5. #35
    Join Date
    May 2006
    Location
    Brisbane
    Age
    80
    Posts
    37

    Default Progress

    Well, my MARS lathe restoration project has progressed to the point where it is operational and being used for some 'real' work (as distinct from producing some replacement parts for itself). All the broken gear teeth have been replaced by screw studs filed to a fair profile which seem to mesh OK without any 'clunks'.

    I think I have discovered the cause of at least some of the 'mashed' gears I have had to fix. It appears that someone must have used the automatic feed and failed to notice that there was some obstruction to the carriage movement, perhaps some material left lying on the bed. Once the carriage ground to a stop against the obstruction, several feed gears lost some teeth.

    That's all fixed now but on testing after reassembly I found that there is also damage to some teeth on the feed rack on the front of the bed, no doubt just at the point where the obstruction occurred.

    The damage is not all the obvious visually, especially since I tried to re-profile the teeth slightly (with a file). Now there is only a slight bump noticeable when using the hand-feed or auto feed to move the carriage. However, it is a serious problem when screw cutting as the carriage is then driven by the half-nuts clamping on the feed-screw. This means that the pressure is on the reverse side of the rack and pinion teeth and they jam quite severely.

    I would appreciate any advice on how to fix these teeth. It's a bit of a pain because the rack is screwed and pinned and I will need to take the carriage off again in order to pull the rack of the pins.

    I have tried to highlight the damaged teeth in the attached picture.
    Cheers,

    J

    ....

    Data isn't Information, Information isn't Knowledge, and Knowledge isn't Wisdom!

  6. #36
    Join Date
    May 2006
    Location
    Brisbane
    Age
    80
    Posts
    37

    Default

    Quote Originally Posted by onthebeachalone View Post
    When I've finished getting the MARS in working condition I might give the old one a coat of paint to make it look like it works.
    The decision has been made to dispose of this very old, heavy duty lathe if anyone is interested. More pictures here. Not the MARS one, the even older, bigger, one here.
    Cheers,

    J

    ....

    Data isn't Information, Information isn't Knowledge, and Knowledge isn't Wisdom!

  7. #37
    Join Date
    Jun 2007
    Location
    sydney ( st marys )
    Age
    64
    Posts
    4,887

    Default

    If the rack is the same as the involute gear dp that I cut there maybe enough room to get in there with a small die grinder and dress the side of the rack.

    If its to hard to get clear access you will have to remove the rack (probably easier in the long run).
    Do the teeth just need cleaning/dressing.

    If you have access to a shaper you maybe able to clean the teeth up with a tool ground to suit,dont think it would need to be perfect.

    If no shaper you could use a pedistal or radial drill if you have one of suitable size,just gind a suitable tool up place in the chuck,spindle in low gear or locked if possable and just raise and lower the quill,the hardest part will be working out your work holding,not hard really just need to put some thought into,( a parallel clamp and shims to adjust depth of cut,the pressure of the cutting tool will hold it from moving).

  8. #38
    Join Date
    May 2006
    Location
    Brisbane
    Age
    80
    Posts
    37

    Default

    Thanks Pipeclay. As far as I can see the teeth are somewhat deformed (as in bent rather than broken). I think they would need some building up before they cold be re-shaped. It is surprising how severe the jamming is (and only in one direction) considering the apparently small amount of deformation. There are two very definite points on the rack where the it occurs.

    Meantime the lathe works fine so long as we don't try to do any thread cutting.

    I'll probably have to remove the rack sometime and clean it up so I an see more clearly what the exact problem is.

    Thanks for your help with the back gearing by the way. It all meshes beautifully.
    Cheers,

    J

    ....

    Data isn't Information, Information isn't Knowledge, and Knowledge isn't Wisdom!

  9. #39
    Join Date
    May 2010
    Location
    Lower Lakes SA
    Age
    58
    Posts
    2,607

    Default

    As a work-around could you wind a string around the carriage wheel shaft with a weight on the end, to keep the teeth loaded the right way? Just so you could screw cut if needed.

  10. #40
    Ueee's Avatar
    Ueee is offline Blacksmith, Cabinetmaker, Machinist, Messmaker
    Join Date
    Dec 2011
    Location
    Canberra
    Age
    39
    Posts
    4,515

    Default

    Hi,
    I'm a bit surprised by the damage you have on the rack. I have the same lathe only later, from the 50's, and i have crashed her a few times but every time the flat belt drive has slipped before any damage has been done. Having said that i have not crashed her with the back gear in and the extra torque may do damage before the belt slips. I plan to make a new rack and pinion for mine anyway as the feed is a bit course, something like 37mm (i use metric as all the dials/screws on mine are metric, but every other part on the machine is imperial) per turn, and it lacks feel. I was planing to cut a new rack on the shaper.
    One of the annoying things i have fixed is the gear and shaft that drives the cross feed. It is helical as it is driven by a worm, but it was free to float back and forth in the apron. This meant every turn or change of direction with the handwheel the gear would clunk against the apron. I just made a few bronze "shims" (about 1/4" in all) to hold it in place.
    1915 17"x50" LeBlond heavy duty Lathe, 24" Queen city shaper, 1970's G Vernier FV.3.TO Universal Mill, 1958 Blohm HFS 6 surface grinder, 1942 Rivett 715 Lathe, 14"x40" Antrac Lathe, Startrite H225 Bandsaw, 1949 Hercus Camelback Drill press, 1947 Holbrook C10 Lathe.

Page 3 of 3 FirstFirst 123

Similar Threads

  1. Mars bar no, Mars lathe!
    By neksmerj in forum METALWORK GENERAL
    Replies: 20
    Last Post: 29th Sep 2012, 08:18 PM
  2. Replies: 52
    Last Post: 9th Aug 2011, 11:37 PM
  3. Lathe Restoration
    By schwartzy in forum METALWORK GENERAL
    Replies: 14
    Last Post: 11th Feb 2008, 12:46 PM
  4. Tool Post Grinder & Myford Lathe restoration
    By DSEL74 in forum METALWORK GENERAL
    Replies: 3
    Last Post: 10th Dec 2007, 12:23 AM

Tags for this Thread

Posting Permissions

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