How to Make a Metal Lathe Knob Turner




About: Just a normal guy trying to make it in life .Good paying job but mindless sometimes .I enjoy making things in my garage to keep my mind going .. Its fun making something new but its more fun taking somethi...

This is my finished  ball and knob turner. You can make knobs out of any material you want . Brass,plastic,aluminum,steel , wood .This style of turner i can create a ball  up to 1 1/4 inch round.

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Step 1: Ball Turner Base Plan

Here are the plans for the base of the ball turner which goes into the cross slide  of the lathe .

Step 2: Machining the Base

pic#1 shows the 1 1/4 inch height i have to maintain and the end of the project.
#2shows milling the edges square
#3 shows milling the a edge slots that fit in the cross feed ..
#4 shows the top milled flush with the cross feed and it fits very snug.

Step 3: Hub for Turner Rotor

Step 4: Ball Turner Rotor Plan

Here is the detailed plans for the  cutter rotor

Step 5: Making the Rotor

pic #1 shows the rotor being drilled through with a  1/4 inch tap drill  and will be threaded  1/4x20
 #2 Shows boring a hole  1 1/4 wide by 3/8's deep to fit a bearing.
#3 shows the rotor with the 1 1/4  outside diameter  x 3/8's thick  x 1/2 inside diameter  bearing press fitted flush to the bottom edge.

Step 6: Milling the Rotor

 pic#1 shows milling the center of the rotor which will help the cutter slide on center of the rotor.
#2,3,4  Show milling the rotor to the correct size for  clearance   to cut the knobs

Step 7: Ball Turner Bit Plan

Here is the detailed plan for the turner bit

Step 8: Making the Cutter Bit Bracket

pic #1 , 2  shows milling the stock to make sure the edges are square
#3 Shows the milled slot for the carbide bit will sit.
#4 ,5  show the bracket milled to the proper thickness.
#6 Shows the 1/4 inch milled adjustment slots .

Step 9: 1/4 and 3/8 Inch Threaded Knob Arbors

 Here is the plan for the arbors for different size threaded knobs.

Step 10: Finished Video of the Knob Turner Turning a 1 '' Aluminum Knob

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    11 Discussions


    7 years ago on Introduction

    great !!!…
    but one question remains to be answered : how did you make the first knob as your tool handle ?
    A bit like the chicken and the egg, I must say…

    Great job.

    Thank you !…

    3 replies

    I build another ball turner which is more like the ones you see online .Which i have to take the compound off .I can send you a link if you like ? please leave a comment if ya like ..


    7 years ago on Introduction

    I started reading the related sidebar and I was like related to outhouses and toilet and camping? Then I made it to survival and I cracked up! I was like yup, I have to agree it'd be tough to survive without balls!

    2 replies

    7 years ago on Introduction

    You've got BALLs!!
    one of those would make a really sweet shift knob.
    I'm thinking I could use this idea with a wood lathe to make wood balls.

    1 reply