Will a Barber Colman #3 cut worm gears?
Close
Login to Your Account
Page 1 of 2 12 LastLast
Results 1 to 20 of 27
  1. #1
    Join Date
    Feb 2007
    Location
    Sterling,VA
    Posts
    257
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    53

    Post

    I am interested in cutting bronze worm gears for my antique Porter Cable sanders. I have researched some and heard that the Barber Colman #3 gear hobbing machine will do this.The gears I want to cut are 2" in dia and 5/8 thick with 21 teeth.I think the worm has a 4 start thread but not real sure. I need help in choosing a machine and the best place to have hobbs made. Also how do you figure out the dim. of the gears?I am new to this and not a machinit by trade but very interested in making these gears.Please help me out. Thanks agian,Cory

  2. #2
    Join Date
    Jun 2003
    Location
    Mebane North Carolina USA
    Posts
    6,576
    Post Thanks / Like
    Likes (Given)
    53
    Likes (Received)
    1867

    Post

    There is a book called "gear cutting practice" by colvin and stanley (??). HAs a lot of good info.

    Ash gear can help with the cutters. Better have deep pockets.

    I believe the B-C will do it. I have the vertical feed attachment for mine to do it but never installed.

    Not sure about the 4 start part.

  3. #3
    Join Date
    Feb 2007
    Location
    Sterling,VA
    Posts
    257
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    53

    Post

    Thanks for the reply.So you have B-C #3? If I buy a B-C#3 and it does not have the vertical feed are you willing to sell yours?How old is you machine and where did you get it, how much was it?Are these the best small gear machine to get?

  4. #4
    Join Date
    Dec 2003
    Location
    suburbs of Ann Arbor, MI, USA
    Posts
    13,038
    Post Thanks / Like
    Likes (Given)
    423
    Likes (Received)
    1011

    Post

    A BC #3 or the later 6-10 models (later cousin) look to be about $5000 from dealers, more or less.

    Then prepare to buy the change-gears, as those above usually come with none. $25-50 each.

    Then prepare to buy hobs...probably $300-500 each.

    Then buy hob-arbors to match the hobs, those might be $500-1000 or you can make your own.

    Then you have to be able to turn the gear blanks to .001" of nominal on OD and ID, and they must be concentric.

    You must create workholding for the blanks, another lathe job that has to be accurately done, either turn the B&S #9 taper or use collets and a straight shaft.

    I'm not trying to pour cold water on a noob's dreams here, but these are in fact the steps you must consider and be prepared to spend $$ on before you can make Prototype Gear #1.

    If you made that first gear and had spent less than $6000, it would be a small miracle, unless somehow you manage to pry the machine out of the hands of an unsuspecting owner for less.

  5. #5
    Join Date
    Feb 2007
    Location
    Sterling,VA
    Posts
    257
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    53

    Post

    Where could I find this machine? I have looked all over the web and everyone wants 10,000.00 for the machine.I am looking for all the help I can get positve or negative so bring it on! I am not a machinist by trade but work in a prototype shop where we have a lathe and mill.I am very interesed in making these gears so any input is welcome.I have a machine I found the guy wants 3750.00 with all the gears,good price? Does the machine have to have vertical feed?Is vertical feed manual or automatic?

  6. #6
    Join Date
    Jul 2004
    Location
    Houston, TX USA
    Posts
    28,942
    Post Thanks / Like

    Post

    Way before you ever buy a machine, you need to get Ivan Law's Gears And Gear Cutting and understand everything in the chapter about worms and worm gears.

    Then you won't need a BC to cut a few worm gears.

    The only justification for such a machine is to make enough gears on it to get your money back. That will be a whale of a lot of gears Cory.

    John

  7. #7
    Join Date
    Dec 2003
    Location
    suburbs of Ann Arbor, MI, USA
    Posts
    13,038
    Post Thanks / Like
    Likes (Given)
    423
    Likes (Received)
    1011

    Post

    I think if you spent your money on a good dividing head complete with plates and tailstock and could grind a form cutter you could be making a few prototypes for $500-1000. It will take awhile to get thru the learning curve and all the indexing, but I think you'll end up with a serviceable result.

    John has given you excellent advice, a BC is a production machine, the books have sections on cycle times and how to maximize production...

  8. #8
    Join Date
    Feb 2007
    Location
    Sterling,VA
    Posts
    257
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    53

    Post

    How else can this worm gear be made? Metal lathe,vertical mill? Has anyone run a Barber Colman #3 gear hobbing machine? Once the BC machine is set up with the right hob and gears it is ready for production?

  9. #9
    Join Date
    Jul 2004
    Location
    Houston, TX USA
    Posts
    28,942
    Post Thanks / Like

    Post

    [img]smile.gif[/img]
    How else can this worm gear be made?
    Read Ivan Law's Gears And Gear Cutting

    John

  10. #10
    Join Date
    Oct 2006
    Location
    Midlothian, TX
    Posts
    314
    Post Thanks / Like
    Likes (Given)
    269
    Likes (Received)
    93

    Post

    I have run the BC's, G&E's and many other gear cutters. Unless your going to make thousands, get a dividing head and make your gears.

    Nathan

  11. Likes Gimpy liked this post
  12. #11
    Join Date
    Feb 2007
    Location
    Sterling,VA
    Posts
    257
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    53

    Post

    Can a dividing head work on a vertical bridgeport mill?Do you still use a hob to cut this gear?I am a beginner so please be patient.Thanks,Cory

  13. #12
    Join Date
    Jul 2005
    Location
    North(very) West(very) Ohio...near exit 13 on OH turnpike
    Posts
    3,680
    Post Thanks / Like
    Likes (Given)
    4
    Likes (Received)
    180

    Post

    I have made them on a Barber Colemen, I, thats right ME, was the down feed attachment ...they paid me 4.50 an hour to downfeed. And blow the chips out and hold a piece of paper under the hob to see when it stopped making dust. These wormwheels were for L&W chuck dividing heads about 1985.

    We also made a couple 1 offs with a horizontal mill, a dividing head, and a single tooth cutter, those wormwheels are not perfect because they have no helix (alto the teeth are cut at an angle), but they work OK, and far better than the torn up ones they were made to replace

    the job IMHO is better done on a horizontal because you built the flycutter on an arbor and use the overarm support so the one end isn't just hanging out in the breeze

    Bill

  14. #13
    Join Date
    Apr 2001
    Location
    Nottingham, England
    Posts
    1,668
    Post Thanks / Like
    Likes (Given)
    78
    Likes (Received)
    154

    Post

    Any old crap universal mill.
    Shaft encoder off a scrap Fanuc lathe.
    Contactor box off a scrap Guildermeister lathe
    $140 worth of electronic bits to go inside.
    Reduction gearbox off an electric motor
    Stepper motor to drive it.
    Bit chopped off an old Myford leadscrew, fluted and hardened as a hob.



    Here's one I did earlier.

  15. #14
    Join Date
    Apr 2001
    Location
    Nottingham, England
    Posts
    1,668
    Post Thanks / Like
    Likes (Given)
    78
    Likes (Received)
    154

    Post

    Re reading your post again and you don't even need to go to this trouble.
    If you are only making the one type of gear then all you need is a gear train from the arbor to the Gearbox like in the picture above, That box is 40:1 ratio so you need a 40 driving a 21 to get the gearbox to generate 21 teeth every revolution.
    How ever this only works for a single start worm.
    If yours is a 4 start worm then the ratio need to be 4 times faster so you want a 160 driving a 21 or a compound train.

    Can you get an old worm and get flutes ground into it as a hob ?

  16. #15
    Join Date
    Mar 2006
    Location
    Oxford, MD
    Posts
    654
    Post Thanks / Like
    Likes (Given)
    13
    Likes (Received)
    56

    Post

    Cory, are you intending to go into production, or just make a couple gears to fix up your own tools?

    It is very possible to free-hob worm gears with nothing but diy tooling, but it will take a bunch of ingenuity and experimentation.

    Here's one I made for my old Jet 1024 power feed.



    Graham

  17. #16
    Join Date
    Mar 2003
    Location
    Vermont
    Posts
    469
    Post Thanks / Like
    Likes (Given)
    111
    Likes (Received)
    122

    Post

    When making replacement gears, I find cutting chips the easy part. What about establishing axial pitch, pressure angle, pitch diameter, tooth thickness, any tooth form modifaication, and some way to inspect accuracy? (Willbird=BCR?)

  18. #17
    Join Date
    Aug 2006
    Location
    Hesperia, SoCal
    Posts
    4,362
    Post Thanks / Like
    Likes (Given)
    987
    Likes (Received)
    646

    Post

    John, WOW!

    gnorbury,
    wuz all enthused, have a 6" rotary table that I bought new in the early seventies, perfect other than stripped worm gear. Looked doable until I realized that each of those 85 or so hob teeth have very accurate looking relief angles, (duh), ground, (or?), on both sides and not a visible nick on any following tooth, with what, .100" or so between? Please share.

    And please Lord, don't let it start with. "very sharp chisel and jewlers loup..." or "check with your significant other for an emery board...." times 170!

    Very impressed Bob

    Edit, on further inspection, did you get away with just top relief?

  19. #18
    Join Date
    Feb 2007
    Location
    Sterling,VA
    Posts
    257
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    53

    Post

    You guys sure know the tricks of the trade.In gnorbury's picture of the home made hob how do you figure out how many flutes to grind into the worm after you make it?What is the best material to make these out of so you can temper them?Does the speed of the mill have to relate to the speed of the gear box?Or the speed of the cutter is a constant and the gear box sets the tooth pattern.What about the feed into the cutter?Can this DIY hobb be used in a lathe, and the gear be set up on the crossfeed?

  20. #19
    Join Date
    Jun 2003
    Location
    Mebane North Carolina USA
    Posts
    6,576
    Post Thanks / Like
    Likes (Given)
    53
    Likes (Received)
    1867

    Post

    Cory, the explanations to your questions are long, sometimes very long. Buy the books mentioned above and read them. You will be light years ahead.

    A B-C is a producion machine. FInd an old horizontal mill they are cheap. I think I have a spare out in the shop.

  21. #20
    Join Date
    Apr 2001
    Location
    Nottingham, England
    Posts
    1,668
    Post Thanks / Like
    Likes (Given)
    78
    Likes (Received)
    154

    Post

    Cory,
    Buy the Ivan Law book Gears and Gearcutting.
    Don't even think about asking another question until you have read this book.


    .


Bookmarks

Posting Permissions

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