Alternative "No Math Required" way to duplicate a bolt circle

WobblyHand said:
Making this assumption can lead to heartache. Measure everything, then decide where those holes need to go! Says the guy whose made in USA arbor threads weren't on centerline. One hole, and it was in the wrong place!
Click to expand...
you do realize that those parts were made at the Fender shop on a friday after lunch..
 
HiltzVW said:
Hi there,

I was recently machining a backing plate for my 922 Logan and had to put the bolt circle on it to match the 4 jaw chuck I wanted to mount.

I decided to use a "no math" method of finding simple bolt circles and thought I would share it here.

First, I aligned the part to the spindle so that the X axis acted as a sort of "mirror image" of the part front to back. I did this by using two gauge pins in the two bolt holes facing toward me.

Then I dialed in the part to find its center. I set zeros on my x and y coordinates.

Next, I went back and indicated one of the gauge pins. Since this was a simple 4 bolt circle, the numbers on my read out after dialing in the gauge pin are all I needed. I could then just reverse the x or y number from + to - in order to find the other holes.

I made a video of it in case you are a more visual learner or I am not describing it well enough.

Click to expand...
some of us do not have DRO........
 
You must log in or register to reply here.
Back
Top