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How Do I Get Two Identical Hemispherical Pieces?

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Hello! Okay I admit it, I'm a super new-guy. I really want to wrap my steering wheel, shift boot and shift knob with leather, and I've been reading and studying all over this forum and some others for a while, so I decided to get started with the knob. It's a billiard ball that I drilled and tapped a hole into. When I fit the leather onto the ball I realized it needed to get stretched a whole lot in order to get into that hemispherical shape I want. I want to have two hemispheres of leather that I can then stitch together with some thick, white polyester thread. My question is this: what do I do from this point to get my hemispherical pieces? Should I glue it down to the ball and then "eyeball" about half way down and cut it with a hobby knife? Should I not glue it, but cut it off about half way and place it flat on the table and make another round piece of leather the same size? Ideally I want to be able to mark the underside with carefully measured marks and then make holes with an awl before stitching. I want to be as precise as possible for this whole project. What would you guys do? Thanks in advance!

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measure the ball and mark the equator on it instead of eyeballing it. Then start stretching leather around it until you can cover the mark. Leave a little room, you can always trim it later. As an additional hint.....get any of the balls 9 or higher and measure the stripe, and mark the middle of it. That would be easier than measuring and marking the 8 ball.

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measure the ball and mark the equator on it instead of eyeballing it. Then start stretching leather around it until you can cover the mark. Leave a little room, you can always trim it later. As an additional hint.....get any of the balls 9 or higher and measure the stripe, and mark the middle of it. That would be easier than measuring and marking the 8 ball.

Hmm... that seems like it would work but if I mark the pool ball directly, that won't work because you have to have some extra leather to pull the leather down onto the ball with, which will cover up the marks I make on the ball.

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What would you guys do?

Measure and mark the equator on the ball, stretch and form the leather, cut to fit. Once the half-a-ball is formed, mark a stitch line equidistant from the edge. Measure the circumference of that line and calculate the best SPI then mark it with wing dividers. Make holes with an awl. Repeat. Assemble the two halves around the core, and sew them with a curved needle. Finish as desired.

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Measure and mark the equator on the ball, stretch and form the leather, cut to fit. Once the half-a-ball is formed, mark a stitch line equidistant from the edge. Measure the circumference of that line and calculate the best SPI then mark it with wing dividers. Make holes with an awl. Repeat. Assemble the two halves around the core, and sew them with a curved needle. Finish as desired.

Thanks

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You could also do it like a baseball, Stohlman's book on cases shows how to do these.

Funny that you are covering a billiard ball, as they are usually left so you can see it.

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You could also do it like a baseball, Stohlman's book on cases shows how to do these.

Funny that you are covering a billiard ball, as they are usually left so you can see it.

Yeah it's the shape and weight of the billiard ball that is desirable to me, and the feel of leather. So many people have an "8-ball" shifter that it's just been done to death and doesn't seem very creative to me. Where's this Stohlman's book you're talking about?

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Measure and mark the equator on the ball, stretch and form the leather, cut to fit. Once the half-a-ball is formed, mark a stitch line equidistant from the edge. Measure the circumference of that line and calculate the best SPI then mark it with wing dividers. Make holes with an awl. Repeat. Assemble the two halves around the core, and sew them with a curved needle. Finish as desired.

Hmm I'm having a lot more trouble with the measuring and the marking than I thought I would have. You see, the ball needs to be held perfectly, and I mean perfectly, to within a fraction of a millimeter straight vertical. If you deviate even a hair, when I mark the ball sides it gets all crooked. In other words marking the ball all the way around the equator is impossible so far. It's as if I would have to mount the ball on a spindle and spin it, in order to make a straight line right down the exact equator.

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If you can't find the center line of the stripe on something like the 9 ball, you could always just roll it through a medium that will stick to it like chalk dust.

Or

Do you know the size of the ball? Standard size for the U.S. is 2.25 inches. Cut a hole in a board that size. Put the ball in, and when it's at it's tightest fit that's the center point.

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The leather case books are available at your local Tandy Leather store. I got mine second hand from someone who was getting out of leather.

I would drill, and install a threaded insert into it first.This will have to be dead on center too. If you know someone with a metal lathe, a milling machine, or a height gage it would be easy to scribe the center down to .001"-.0001" depending on what method is used . Plenty close for stretchy leather. I am a machinist, so to me this is an easy option for me.

A friend in high school had a buddy who put a tanned deer scrotum over his shifter. The girls liked it up until they found out what it actually was.

Take the shifter knob, and form the leather over it. 2 times so that you have 2 halves formed. Bore a hole in a piece of wood, or other suitable material so that the leather wrapped ball stops at its equator. Take a knife, and trim the leather off flush with the board. Repeat. It is better to be a little short, as the leather can stretch to fill a small gap, and pull tight onto the ball. Another option would be to lace it up, and the lacing will cover a larger gap, and form a grip ring around the shifter knob. Yet another option is to trim it tight, and just glue it on without stitching. Do a decorative overlay on the seam.

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If you are having trouble marking the ball, but you have already drilled and tapped it. Screw a short all thread into it and chuck it up in a drill to spin it.

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One thing you might try is to cut the hole in a piece of wood and then with your leather soaking wet push the leather and the ball into the hole past the half way mark and then let the halves dry completely, once they are dry then you can trim off the leftovers a little at a time until you get them to fit on the ball, I've tried doing this with a tennis ball and it takes a lot of trimming and sanding. If you can get a flat cut then you can glue a piece of sandpaper to a board and sand it like a bowl and your cut line should stay straight. Hope this helps.

Peace

Bryan

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Others have explained how to pull the hide around the ball. Here's the easiest way to get the mid line, or "equater" if you will. Measure the diameter of the ball then divide the measurment by 2. Lets say the result is an inch and a half or 1 1/2" Cut a 1 1/2" wide strip of poster board or file folder or other stiff card stock roughly three times the first measurment... and add an inch. That should give you something like 1 1/2' X 10". Have you figured it out yet? OK roll the strip of paper into a circle, lap the end by an inch and tape it together and set the ball inside the circle on a good flat surface and trace around the edge of the card stock circle!!!!

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If you use belly leather it will be easier to form tightly around the ball.

Ray

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