Better to ask forgiveness...

[pfrench]

Well, I converted my four jaw chuck to work on my three-bolt spindle with my drill press.
Both chucks already fit tightly onto the spindle nose (correct term?)

My options were:
* drill three holes into the spindle
* drill/tap three holes into the adapter plate
* drill/tap two holes into the four-jaw

I chose to drill and tap into the chuck. Not sure if this was the right decision, but it's working great. < 1 thou runout.
Just sharing in case anyone's interested.

 

[francist]

It’s working — sounds like the right decision to me!

 

[RaisedByWolves]

Nothing wrong with that, lots of ways to skin the cat.

 

[Janderso]

By your title I thought maybe you bought something the boss might object to.
Looks like you did a fine job there!!

 

[dabear3428]

Well, I converted my four jaw chuck to work on my three-bolt spindle with my drill press.
Both chucks already fit tightly onto the spindle nose (correct term?)

My options were:
* drill three holes into the spindle
* drill/tap three holes into the adapter plate
* drill/tap two holes into the four-jaw

I chose to drill and tap into the chuck. Not sure if this was the right decision, but it's working great. < 1 thou runout.
Just sharing in case anyone's interested.

care to share how you located the new holes? i'm doing the same for my lathe.

 

[pfrench]

care to share how you located the new holes? i'm doing the same for my lathe.

The four-jaw came with the adapter plate, which has holes for 3 and 4 jaws.
I used a transfer punch to ding the chuck through the two needed holes in the adapter plate.
Then carefully drilled and tapped the two new holes in the 4-jaw

 

[pfrench]

The four-jaw came with the adapter plate, which has holes for 3 and 4 jaws.
I used a transfer punch to ding the chuck through the two needed holes in the adapter plate.
Then carefully drilled and tapped the two new holes in the 4-jaw

And, to be frank. I ended up drilling four holes because the first set of them weren't perpendicular enough. The second set worked, barely.

 

[dabear3428]

The four-jaw came with the adapter plate, which has holes for 3 and 4 jaws.
I used a transfer punch to ding the chuck through the two needed holes in the adapter plate.
Then carefully drilled and tapped the two new holes in the 4-jaw

I'm planning on using my mini mill to make the holes perp. but getting the layout may be a problem for me, but it is a cheap chuck soo.