Molding challange how do you do this one?

Maybe you can support the ball on steel pegs, fill in plastic around it, then while still soft(?) remove the pegs and fill the holes, hoping for a weld or at least a good seamless joint? Maybe use epoxy to fill in, using a vacuum chamber to ensure no bubbles?

Tim

What kind of plastic are you molding over the ball? If soft you might be able to dip it. Hard plastic might be easier to make a shell and seal the ball inside.

Has to be pretty hard. It will be urathane resin.

Tom

"Democracy is two wolves and a lamb voting on what is for lunch. Liberty is a well armed lamb protesting the vote."

A tiny seem is ok. I was thinking along the lines of a jig like you mentioned. something to support the ball in the mold. This is a tricky one.

"Democracy is two wolves and a lamb voting on what is for lunch. Liberty is a well armed lamb protesting the vote."

No Sheeples wrote: (clip) Im using a thermal set 2 part plastic so melting is not a problem.(clip) ^^^^^^^^^^ I did something like this once using a two-component resin system. I made spacer blocks out of the resin, and used them to hold a leaf in position while I poured the same resin over the leaf. After it cured, the spacers were not visible. They have to be smooth so no air is trapped on the surfaces, or you will see bubbles. In fact, bubbles were me no one problem. I am told that pulling a vacuum would have helped.

Noooooo! That would go right through the drum head! This is for plastic coated pinballs! I allready make drum beaters. Here, you can check out what I make here.

"Democracy is two wolves and a lamb voting on what is for lunch. Liberty is a well armed lamb protesting the vote."

Yea, I think the ticket here is going to be makink a plastic jig that looks something like ball and jacks so that the ball can rest centered in the mold while I pour the plastic in. Gonna be a tough one. Keep the ideas comming!

"Democracy is two wolves and a lamb voting on what is for lunch. Liberty is a well armed lamb protesting the vote."

When I look at a rubber ball it's usually two hemispheres joined together. Sounds like yoiu are making the same thing with metal instead of air in the middle.

Coaxial DC electromagnet above the ball, horizontal sensing coil (axis vertical) surrounding the ball and mold, and feedback controls system. The coil senses ball height by change of inductance and drives the control system to power the magnet, reducing current if the ball is too high and so forth. The field would be divergent (radial gradient) so the ball would stay self-centered horizontally. The control system would need to be non-linear because the force exerted on the ball by a given magnetic field varies inversly as the square of the distance between the ball and the electromagnet.

No pegs, no seams!

Post photos!

A little to high tech for me, but I like it!

"Democracy is two wolves and a lamb voting on what is for lunch. Liberty is a well armed lamb protesting the vote."

I made many thousands of steel cores for checks balls, as you are describing. The split mold had grooves to position the 3 pins that supported the core in the mold. Steel pins were used.

What about panning? This is how they make many candies, such as jelly beans and jaw breakers.

You take a bunch cores and put them in a rotating drum then begin pouring stuff on them. Let them roll around, sometimes they run heated air inside the drum to dry them. Then do it over to get another layer.

You might have to do something to the surface of the ball to get the stuff to stick to. Here's a video of the process:

If you only need to make a few balls at a time, you can make you own panning machine by soldering 2 salad bowls together and connecting them to a food processer to get them spinning.

Good luck. I love to hear if you try this. Jas> Hey fellow metal heads, I have become very proficient at making silicone, and