Page 1 of 2 12 LastLast
Results 1 to 15 of 16
  1. #1
    Join Date
    Oct 2010
    Location
    melbourne, laverton
    Posts
    1,910

    Default fancy mower repair.

    hi every one. A MAte has this damaged reel he would like repaired.

    97303671_1385008615219973_7415523441865916416_o.jpg
    A woodruff key fits in the damaged slot. I think the reel is driven via the woodrufff key buy a chain sprocket.
    I was thinking just cut a new key slot for key on the other side of shaft with a woodruff cutter. maybe clean up the
    shaft with lathe or file.
    do you think id get away with this with out repairing the damage by building up shaft??


    thanks
    aaron

  2. #2
    Join Date
    Oct 2010
    Location
    melbourne, laverton
    Posts
    1,910

  3. #3
    Join Date
    Oct 2004
    Location
    Southern Highlands NSW
    Posts
    1,894

    Default

    Some weld of the damaged keyway might help strengthen the shaft, which could be weakened by more milling.
    The shaft needs to be removed anyway, so cleaning up the weld on a lathe is little extra work.
    It might work even if it wasn't repaired, but I suppose it would be more inconvenient if the shaft end broke off.

  4. #4
    Join Date
    Oct 2010
    Location
    melbourne, laverton
    Posts
    1,910

    Default

    Quote Originally Posted by nadroj View Post
    Some weld of the damaged keyway might help strengthen the shaft, which could be weakened by more milling.
    The shaft needs to be removed anyway, so cleaning up the weld on a lathe is little extra work.
    It might work even if it wasn't repaired, but I suppose it would be more inconvenient if the shaft end broke off.
    I thought while its apart fix it . A replacement reel i believe is $350.
    I hadnt thought of removing the shaft from the reel. that would make it easier to mount for milling.
    Ill have to think about that when i see it for reel.
    I just thought id hold one end on a 3 jaw then support the damaged end with tail stock.
    Plus i havnt built up shaft with an arc welder before. Shouldnt be to much drama but is it worth the effort.

    reel photo.
    100738889_202104080809855_2558294838910910464_n.jpg

  5. #5
    Join Date
    Jan 2004
    Location
    Mackay North Qld
    Posts
    6,446

    Default

    azzrock,
    Great looking mower. The Brisbane City Council used them to mow the footpaths when I was a kid in the late 1950's.
    They cut beautifully.

    A heads up,should you opt for welding. Don't weld the shaft circumferentially .Its possible that the stress created by the weld as it shrinks can create a shear fault.

    Although the load upon it will not be heavy there's always the chance of fracture when the welded this way. I only mention this as I have seen a 125mm (5") steam turbine spindle shear off because of this very reason.


    Undercut with the lathe or grind a groove to take out the corners of the key pocket. Reduces slag trap that occur in squared corner.

    I guessing the diameter there is around 20mm so stick with 3.25mm electrodes. That way there are fewer electrodes creating less overall heat input and less chance of distortion problems. If I viewed the illustration correctly there no a lot of shaft overhang, so little or no problems with distortion at that point.

    To further minimise distortion weld opposite beads as in:

    12 o'clock then 6 o'clock
    then
    9 o'clock then 3 o'clock

    back to, beside 12 o'clock then beside 3 o'clock
    and follow the pattern. It balances out the distortion forces. Essentially it is welding beads opposites against opposites.

    A trick I have also used is to use a marker further up the shaft to mark 12 ,6, 9 and 3 ock's so I don't lose track of what ock I am working on and weld out of sequence.

    If I have forgotten something the other guys will chime in, hopefully.

    Grahame

  6. #6
    Join Date
    May 2011
    Location
    Murray Bridge S Aust.
    Age
    71
    Posts
    5,942

    Default

    Another option. I had a 4 cylinder car crankshaft, that the harmonic bolt disappeared from, allowing the drive gear to rock back and forth, wearing the woodruff key slot in the crankshaft. A friend of mine whose brother runs a engine reconditioning shop, cut the keyway wider and made a stepped key for it.
    Kryn
    To grow old is mandatory, growing up is optional.

  7. #7
    Join Date
    Oct 2010
    Location
    melbourne, laverton
    Posts
    1,910

    Default

    Hi Grahame and Kryn.
    thanks for your input.
    Grahame so weld along the shaft . ok good tip . Im not sure what you mean by undercut. Is that machine out the damaged part of shaft?
    what sort of electrodes would be best?
    Kryn good tip as well i suppose ill deside when i have the reel in my hand.
    thanks again
    aaron

  8. #8
    Join Date
    Jan 2004
    Location
    Mackay North Qld
    Posts
    6,446

    Default

    Hi Azzrock

    Yes machine out the damaged or corroded bits.

    The term undercut was used by the fitters and turners I worked with when a shaft was cut or turned below its original diameter.

    The required weld deposit was placed in the undercut.

    I found a diagram that wil help
    follow this link

    https://www.yourarticlelibrary.com/m...-diagram/83389

    Electrodes definitely 3.2mm and preferably 6013 but 6012s will do. So long as there are no inclusions a bit of a rough ripple pattern means nothing if its going to be machined.

    To get the needed build up height you overlap 2/3rds over the last bead.You want to avoid any valleys between the laid down beads.
    Its easy to machine off but a real PITA to remove from the lathe, reweld and place back in in the lathe and center..

    Always aim to over weld by a slight margin. This was explained to me by irate fitter and turners when I had failed to reach the overbuild height and they ended up machining thin air. Grumpy sods!



    Grahame

  9. #9
    Join Date
    Aug 2008
    Location
    near Rockhampton
    Posts
    6,216

    Default

    I would not replace it with a woodruff key. I think industry used them in the past because they were cheaper to cut then a featherway key. But woodruff keys weaken the shaft and each one needs a special cutter.
    Gold, the colour of choice for the discerning person.

  10. #10
    Join Date
    Oct 2010
    Location
    melbourne, laverton
    Posts
    1,910

    Default

    Quote Originally Posted by .RC. View Post
    I would not replace it with a woodruff key. I think industry used them in the past because they were cheaper to cut then a featherway key. But woodruff keys weaken the shaft and each one needs a special cutter.
    nice tip thanks RC

  11. #11
    Join Date
    Oct 2010
    Location
    melbourne, laverton
    Posts
    1,910

    Default

    hi Grahame,
    thanks Great info.

  12. #12
    Join Date
    Aug 2008
    Location
    Charlestown NSW
    Age
    65
    Posts
    1,669

    Default

    Grahame.
    Would you recommend any sort of preheat/post extended cool down on a shaft that size?
    I have a potential similar repair on my lathe, if I cant clean up the keyway and make a stepped key.

    thanks
    Peter

  13. #13
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,438

    Default

    Hi Peter, Guys,

    I don't think pre-heating the shaft will make a lot of difference, its going to get very hot anyway when you weld it. I would just clean it well and get on with filling the cavity. Machine it back to true and put a feather key in there.
    Best Regards:
    Baron J.

  14. #14
    Join Date
    Apr 2004
    Location
    Notting Hiĺl (Melb) or Echuca
    Age
    64
    Posts
    179

    Default

    Well I have learnt something. 2 things
    1) All this mention of feather keys left me wondering what they are. Woodruff keys I had met, and crawled after on the workshop floor.
    Found this document. http://www.ondrivesus.com/documents/...ather-keys.pdf
    2) Graeme's guidance on building up a shaft by welding to avoid creating cracks

    Thank you 👍
    cheers
    David

    ------------------------------------------------
    A society grows great when old men plant trees whose shade they’ll never sit in. (Greek proverb)

  15. #15
    Join Date
    Oct 2010
    Location
    melbourne, laverton
    Posts
    1,910

    Default

    hi havinago
    thanks for the link.an interesting read.
    the guys on here are great when you ask what they think.
    aaron

Page 1 of 2 12 LastLast

Similar Threads

  1. Replies: 16
    Last Post: 1st Mar 2017, 10:39 AM
  2. We're not fancy but dirt cheap
    By BobL in forum METALWORK GENERAL
    Replies: 5
    Last Post: 26th Sep 2016, 11:39 AM
  3. Petrol mower conversion
    By neksmerj in forum METALWORK GENERAL
    Replies: 44
    Last Post: 5th Oct 2015, 12:58 PM
  4. Mower deck rebuild
    By Steamwhisperer in forum METALWORK GENERAL
    Replies: 23
    Last Post: 11th Dec 2013, 06:17 AM
  5. old victa mower flywheel
    By Swarfmaker1 in forum METALWORK GENERAL
    Replies: 15
    Last Post: 18th Oct 2012, 07:52 PM

Posting Permissions

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