What's new
What's new

Ball Knurling with antique knurls

rivett608

Diamond
Joined
Oct 25, 2002
Location
Kansas City, Mo.
This was a post I did on IG and FB today, thought I would add it the discussions we have had in the past.

Working on some BALL KNURLING, an old style of knurling, most have seen the ROPE style, but this is more rare. This is for a project I’m doing for Chris Toledo’s @ibuildsmallthings latest masterpiece commissioned by the National Museum of Toys and Miniatures @toyandminiaturemuseum .

I have done ball knurling in miniature before but never this big. What makes this different from modern diamond pattern knurling that is done by tooling that actually cuts into the metal. Ball knurling and many of the other decorative styles of the 19th century, are done by forming. moving the metal under quite a bit of pressure. For this project, I first made a form tool and turned a shaped curve close to the size of the ball, about 1/16”. The diameter of the part is about 5/8”. Then using one a large collection of antique knurling wheels in my shop I started to produce the chain of balls effect. It became clear that as it pressed into the brass and started to form it to shape, the bits and pieces breaking away were getting caught up in the knurling wheel and effecting the design. Trying to brush these off didn’t work even at the slow speed I was turning, it caught the brush and destroyed it. So I use an air gun to blow the swarf out.

In the process I used my microscope with a 32” digital screen to inspect the work. I can see where the force is moving the brass into shape, it is almost like it is forging it. As each ball is formed I could see the seam closing at the top, it was also interest that the diameter grew by about .010”. You can also see a little flashing on the edge just like any other forged piece. After a little clean up they look great.

It was fun to finally use these knurls after owning them for about 20 years, now on to the next fun part of this project.​

 

Attachments

  • IMG_3954.jpeg
    IMG_3954.jpeg
    1.5 MB · Views: 104
  • IMG_3955.jpeg
    IMG_3955.jpeg
    1.6 MB · Views: 106
  • IMG_3958.jpeg
    IMG_3958.jpeg
    1.2 MB · Views: 104
  • IMG_3964.jpg
    IMG_3964.jpg
    2.1 MB · Views: 106
  • IMG_3959.jpeg
    IMG_3959.jpeg
    1.8 MB · Views: 105
  • IMG_3962.jpg
    IMG_3962.jpg
    2.1 MB · Views: 96
that's really cool! Presumably the circumference of the material to be knurled must be in increments of one ball? Did you figure that out beforehand or just wing it?
 








 
Back
Top