Half Ball Cup Formation Method? - Page 2 - Router Forums
 6Likes
Reply
 
LinkBack Thread Tools Display Modes
post #11 of 15 (permalink) Old 11-22-2019, 09:39 AM
Registered User
 
roxanne562001's Avatar
 
Join Date: Feb 2012
Country: United States
First Name: Roxanne
Posts: 2,124
 
Default

Welcome to the forum. If you drill the hole with an adjustable circle cutter aka fly cutter in a drill press then use a round over bit with a pilot bearing to form the rounded edge. Then sand to get the exact fit you want.
OutoftheWoodwork and Nickp like this.
roxanne562001 is offline  
Sponsored Links
Advertisement
 
post #12 of 15 (permalink) Old 11-23-2019, 07:00 AM
Registered User
 
Join Date: Mar 2013
Country: South Africa
First Name: Biagio
Posts: 472
 
Send a message via Skype™ to Biagio
Default

Lee Valley has a pneumatic ball nose sanding drum, which looks almost purpose-designed for the sanding part of this job.
Biagio is offline  
post #13 of 15 (permalink) Old 11-23-2019, 08:24 AM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 30,682
 
Default

Two mating flats made w/ a fostner bit...
as soon as the rim of the bit touches the ball stop drilling...

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”
Stick486 is offline  
Sponsored Links
Advertisement
 
post #14 of 15 (permalink) Old 11-23-2019, 10:22 PM
Registered User
 
Join Date: Mar 2013
Country: South Africa
First Name: Biagio
Posts: 472
 
Send a message via Skype™ to Biagio
Default

MSAL,
I think you are on the right track. 40mm Forstner bits are fairly common. A cylindrical 40mm flat-bottomed hole, 20mm deep, will hold your ball exactly as you want it, with no complicated sanding, etc. The fact that it is not a half-round cup hole, will not be visible. If you want the ball to rotate in the hole, so much the better - only one friction point at the bottom of the hole. If you do not want it to rotate, one dab of hot-melt glue at the same location.
Interesting how one gets to overthink situations.
Biagio is offline  
post #15 of 15 (permalink) Old 11-24-2019, 12:01 AM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 30,682
 
Default

Quote:
Originally Posted by Biagio View Post
MSAL,
I think you are on the right track. 40mm Forstner bits are fairly common. A cylindrical 40mm flat-bottomed hole, 20mm deep, will hold your ball exactly as you want it, with no complicated sanding, etc. The fact that it is not a half-round cup hole, will not be visible. If you want the ball to rotate in the hole, so much the better - only one friction point at the bottom of the hole. If you do not want it to rotate, one dab of hot-melt glue at the same location.
Interesting how one gets to overthink situations.
you could use the point from the fostner bit to accurately install a dowel, dowel screws or a blind nail...



.
Attached Images
 

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”

Last edited by Stick486; 11-24-2019 at 12:07 AM.
Stick486 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Router Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome