Small bandsaw mod to cut steel

Discussion in 'Machine Modifications' started by bazmak, Nov 6, 2015.

  1. Nov 6, 2015 #1

    bazmak

    bazmak

    bazmak

    BAZMAK

    Joined:
    Dec 12, 2012
    Messages:
    1,967
    Likes Received:
    1,105
    I have a small bandsaw that i used for cutting timber up to 3" thick
    Now i used it more for cutting metal,will cut up to 70mm thick alum
    and 25mm brass with ease but too fast for steel.The blades i was using are cheap quality from the local hardware store and touching steel just took the edge right off.I found a new supplier and twoo blades were ordered,cheaper and better quality.The invoice stated they were suitale for cutting steel but at a recommended speed of 300fpm.My machine had a speed of 2300fpm
    I read a post by Brian Rupnow where he had added extra drive pulleys to his bandsaw to reduce the cutting speed.Could i do the something similar ?
    the 150w motor ran at 1450rpm from a 17t pulley to a plastic 26t pulley fitted to the 240mm dia blade wheel.I checked and decided that although very tight i could squeeze in an additional idle pulley.I made 3 new pulleys 15t,40t and 48t
    The existing 17t was modded and repositioned on the motor shaft,the 15 and 40t were bolted together with a roller brg and fitted on a new idler shaft
    the 48t pulley was bolted to the blade wheel.I bought a new 65t belt and reused the existing.Very tight and tricky.
    Result motor 1450rpm x17/40 = 616rpm
    616 x 15/48 = 193 rpm=475 fpm still a touch fast but works well
    Cuts thru 12 thk steel plt slowly but with ease.Ok for alum and brass
    and still ok for timber,slower but much more torque,no bogging down aS YET[​IMG][​IMG][​IMG][​IMG]
     
  2. Nov 6, 2015 #2

    toolznthings

    toolznthings

    toolznthings

    Well-Known Member

    Joined:
    Dec 11, 2013
    Messages:
    255
    Likes Received:
    177
    Nice job on the conversion !

    Brian
     
  3. Nov 6, 2015 #3

    Ken I

    Ken I

    Ken I

    Project of the Month Winner!!! Project of the Month Winner

    Joined:
    Oct 31, 2010
    Messages:
    1,335
    Likes Received:
    91
    I have the same bandsaw and have been wondering about modifying it for some time.

    In fact a while ago I posted a question.

    Question answered - now to get my A in G and make the mods.

    Thanks for the post.

    Regards,
    Ken
     
  4. Nov 6, 2015 #4

    Chiptosser

    Chiptosser

    Chiptosser

    Chiptosser

    Joined:
    Aug 5, 2013
    Messages:
    110
    Likes Received:
    19
    What make and model of bandsaw did you modify?
     
  5. Nov 6, 2015 #5

    Brian Rupnow

    Brian Rupnow

    Brian Rupnow

    Well-Known Member Project of the Month Winner

    Joined:
    May 23, 2008
    Messages:
    10,285
    Likes Received:
    3,073
    Good stuff Bazmac!!! I really like your non-slip pulleys.----Brian
     
  6. Nov 6, 2015 #6

    bazmak

    bazmak

    bazmak

    BAZMAK

    Joined:
    Dec 12, 2012
    Messages:
    1,967
    Likes Received:
    1,105
    the existing drive was with a toothed belt.Std section 9mm wide x 5mm pitch
    I ground a simple single point tool as shown.The sizes were determined by
    physical constraints and ease of the homemade deviding head,using the existing belt and a new one the same size gave me ctres etc that would just fit
    Quite surprising how easy it was to make the the simple timing pulleys
    Would be ideal to replace gears/sprockets etc on models
    The bandsaw is a simple Draper 10" model that i brought from the UK Works well for its size.Any cheap model from the local hardware store would work well for $100 or so.Its main benefit for me as i have mentioned before is
    its light weight,i just pick it up and use/store it where i want.Now only time will tell,i need to get cutting steel and see how long the blades last,torque seems much better and no bogging down.It seems a bit tight at the moment,if the belts dont stretch a tad i will have to look at reducing the tension.Speeds may seem a little high but thats no load speed so will be lower when cutting
    First impressions on cutting 12mm mild stell were very good
     
  7. Nov 6, 2015 #7

    Brian Rupnow

    Brian Rupnow

    Brian Rupnow

    Well-Known Member Project of the Month Winner

    Joined:
    May 23, 2008
    Messages:
    10,285
    Likes Received:
    3,073
    I was told by the people who make metal cutting bandsaw blades that the minimum diameter they would recommend for bi-metal blades on a bandsaw to be 14" wheels. They said that any smaller diameter than that causes premature blade failure. I have no idea as to whether or not this is so, but there seems to be about a zillion horizontal swing arm and portable bandsaws out there with much smaller wheels.---Brian
     
  8. Nov 7, 2015 #8

    bazmak

    bazmak

    bazmak

    BAZMAK

    Joined:
    Dec 12, 2012
    Messages:
    1,967
    Likes Received:
    1,105
    the blades i use are only 6mm wide and i have also ordered a 10mm wide one
    I have had a couple of bandsaws this size and have had no trouble,my previose
    one had a slower speed and cut up to 6mm mild steel with no problems.The chinese hor./vert bandsaws you guys are used to use much wider blade.What surprises me how much more ummff this unit has now its geared down.Not bad for a 150w motor.I am doing a series of tests with different matls and the new saw blades,will keep you all informed.
     
  9. Nov 7, 2015 #9

    quickcut

    quickcut

    quickcut

    Member

    Joined:
    May 19, 2012
    Messages:
    8
    Likes Received:
    2
    I was told by a local saw doctor that the minimum diameter of a band saw wheel should be 1000 times the blade thickness. that is for a blade .6 mm thick the wheel would be 600mm diameter. It seems excessive but admittedly he makes blades for saw mills. I saw blades there that were 3mm thick and 127mm wide. I'll keep my hands in my pockets.
     
    Last edited: Nov 7, 2015
  10. Nov 16, 2015 #10

    bazmak

    bazmak

    bazmak

    BAZMAK

    Joined:
    Dec 12, 2012
    Messages:
    1,967
    Likes Received:
    1,105
    Just to keep you all up to speed.While making a 3 way toolpost i decided to push the bandsaw to the limit.I tried cutting a piece of 35mm thk m/s but very optimistic/hopeful.The saw cut about 3" in length before the blade lost its edge and the belt started jumping teeth.Not successful.So i retensioned the belts and fitted a new blade.I made a setsquare from 3mm thk M/S it cut quickly and easily.Then i tried 6mm plt again no problems.I also cut a piece of 5ox12 flat bar which was slow but successful.I think thats about the limit.What did surprise me was that the motor never stalled when it bogged down it was due to belt slip.
     
  11. Nov 28, 2015 #11

    bazmak

    bazmak

    bazmak

    BAZMAK

    Joined:
    Dec 12, 2012
    Messages:
    1,967
    Likes Received:
    1,105
    I had need to cut some 63mm thick alum which i had done before
    The saw was now too slow and could not do it.So a couple more minor mods
    removed the idler pulley,change the wheel pulley and back to the original
    Takes 5mins to change from slow to fast speed but i can live with that.
    I then cut up some 63,50,and 40mm alum at fast speed. NO PROBLEMS[​IMG]
     
    larry1 likes this.
  12. Jan 6, 2016 #12

    bigo

    bigo

    bigo

    Member

    Joined:
    Aug 15, 2012
    Messages:
    17
    Likes Received:
    5
    I have done 2 band saws with treadmill motors both worked great, also make your own blades out of bulk material and silver solder them together.

    101_0579.jpg
     
    bazmak and larry1 like this.
  13. Jan 6, 2016 #13

    Blogwitch

    Blogwitch

    Blogwitch

    Ex Bogstandard

    Joined:
    Dec 26, 2008
    Messages:
    3,631
    Likes Received:
    616
    Baz,

    I have an old Black & Decker three wheeled hobby bandsaw, with a recommended blade width of, like yours, about 6mm.

    For the last twenty years, after fitting ball raced roller guides, I have been using 1/2" blades, and recently changed over to bi-metal ones. They cut through almost anything with ease.

    I am lucky as it does have a method of changing speed whilst on the run.

    The reason I am saying this is that you don't need big machines to do jobs like this, these small ones cope very well if set up correctly and you don't push them too hard.
    BTW, I still have the original plastic wheels in mine and they still look and work like new. I was expecting it to be a throw away job after a couple of years.

    John
     
    bazmak likes this.
  14. Jan 6, 2016 #14

    bazmak

    bazmak

    bazmak

    BAZMAK

    Joined:
    Dec 12, 2012
    Messages:
    1,967
    Likes Received:
    1,105
    AGREE WITH EVERTHING YOU SAY BLOGWITCH.
    Bigo,as a sheetmetal apprentice,one of my jobs was to make the bandsaw blades for the men.Cut to length,grind feather two ends then silver solder and clean up. Then we got a new bandsaw where the jig was built in to the machine
    and the two ends were were clamped and forced together under pressure like an arc welder.Just had to clean off the joint.If i could find a supplier of band saw blade i could make my own but then again how many do i use?
     
  15. Jan 6, 2016 #15

    canadianhorsepower

    canadianhorsepower

    canadianhorsepower

    Well-Known Member

    Joined:
    Oct 22, 2011
    Messages:
    1,611
    Likes Received:
    303
    I do mine at home, I go to CTC or any hardware store
    and get the clearance band saw blade they have and the longer one.
    Then cut them to my length. One of the Home Machinist magasine
    had a good article on that a few month ago.
     
    bazmak likes this.
  16. Jan 7, 2016 #16

    Blogwitch

    Blogwitch

    Blogwitch

    Ex Bogstandard

    Joined:
    Dec 26, 2008
    Messages:
    3,631
    Likes Received:
    616
    For people in the UK and in the 'know' all use this site for their bandsaw blades. Very reasonable prices and great blades that seem to last forever if you choose the correct ones for the job.

    http://tuffsaws.co.uk/


    John
     
  17. Jan 7, 2016 #17

    Swifty

    Swifty

    Swifty

    Well-Known Member

    Joined:
    Mar 6, 2012
    Messages:
    2,253
    Likes Received:
    811
    Bazmak, if you seek out a saw blade resharpening business in your area, you may find that they handle bandsaw blades as well. We have a local one 30 minutes from where I live, Ace Saw Service, that make blades up to suit, but I'm sure that they would sell any length off the roll.

    Paul.
     
    bazmak likes this.
  18. Jan 7, 2016 #18

    Herbiev

    Herbiev

    Herbiev

    Administrator Staff Member Administrator Moderator

    Joined:
    Jan 6, 2011
    Messages:
    2,287
    Likes Received:
    289
    We have Elite Saw works at Lonsdale south of Adelaide that make up blades.
     
    bazmak likes this.
  19. Feb 16, 2016 #19

    bigo

    bigo

    bigo

    Member

    Joined:
    Aug 15, 2012
    Messages:
    17
    Likes Received:
    5
    I use doall blade material and silver solder my own, 309-047 1/4" 6 pitch and 308-601 1/4" 32 pitch
     
  20. Oct 22, 2017 #20

    bazmak

    bazmak

    bazmak

    BAZMAK

    Joined:
    Dec 12, 2012
    Messages:
    1,967
    Likes Received:
    1,105
    Reposted this thread for info for current question/thread on using small band saws
     

Share This Page