45 degree thumb With oval thumb

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drill
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45 degree thumb With oval thumb

Post by drill »

Hello!
I have read all i can find regarding the
45 degree drilling thumb but still confuesed when it comes to ovals.
I have left/right 1/16 ,forward 1/16.
I rotate the ball in the mill, drill the first hole and then
Move left and right (x in the picture ),same sum to make the oval.
The oval hole is now offset from the centerline.

Lefty!!

Is this accurate?
From where shall I lay out the span if clt
Drilling or not?
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drill
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Re: 45 degree thumb With oval thumb

Post by drill »

Okey, feels like its hard to answer my question.
I Will therefore simplify/ split up my question.

When drilling 45 degree ovals, shall the first hole be placed
In the center/origo of x,y,45 degr line? And the others on each
Side? If yes it means that my drilling in the picture is wrong.
Arkansas
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Re: 45 degree thumb With oval thumb

Post by Arkansas »

It's easier to make your first cut on the span line and just make your oval cuts in one direction going away from your fingers. That'd be in the X- direction in your picture. But you'd need to hit the centerline and the cut line. It looks like you missed by a 1/4" or so from where you should have started the cut.

On the ball you have pictured you haven't drilled the fingers yet. If that's still the case, just redraw the center line using the center of the top of the thumb hole you drilled and you should be good to go.
James Talley
drill
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Re: 45 degree thumb With oval thumb

Post by drill »

Tanks, for the reply!
Then I prefer to use the x line and span line as
Center of the hole. And drill left and right from there.
But you prefer to start from there and go in one direction?
Away Left? Why?
I understand there are plenty of different methods.
In your the center of the oval is on the Palm side.
In my (above) the center of the oval is at the span line.
What is most common??

Thanks for helping me!
Arkansas
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Posts: 477
Joined: January 24th, 2012, 11:02 pm
Positive Axis Point: 4 1/2 Left x 3/4 Up
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Rev Rate: 350
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Heavy Oil Ball: Guru Mighty
Medium Oil Ball: Guru
Light Oil Ball: Torrid Affair
Preferred Company: Radical

Re: 45 degree thumb With oval thumb

Post by Arkansas »

I guess it depends on how you determined your span measurements. If you copied an existing ball, as long as you measured from the center of the thumb for the span you should be fine the way you drilled it. If you measured from the top of the hole, I think you'll be off. If you measured your hand and are translating that to the ball, I think your ring finger will be long and your middle finger short. I could be wrong though. It wouldn't be the first time.
James Talley
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Re: 45 degree thumb With oval thumb

Post by Nsane »

ifI do the 45° drilling i mark the center of the drillbit @ the Gripcenterline. Than i draw the 45° LINE FROM THAT POINT. If not your hole will be the half bitsize off. Turn the ball and center the drillbit. From there it is on your side in what direction you drill first. The final product will ba a oval thumbhole 45° in the right position.

Thomas.

PS:
I had the same case when i was unconcentrated. I forgot to draw the 45° line from holecenter.

Thomas
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