Don’t mind me, just bookmarking in-thread.
LOL, dude i am so buying a larger than normal plastic D20 and sending it to you to make it into a stick top.
It would be nice if someone could find one of those, but I know a few days ago when I was looking around on google I could only find 1/4" blunt diamond bits as the largest size and everything after that was a core bit.
Although if you get a 1/4" blunt bit then you can try what I suggested before where you use the 1/4" bit first and then wided the hole with the 5/16" core bit.
That’s a shame. I don’t think widening a hole with a core bit would work very well though. Now I could do a 1/4" hole and widen it using my 5/16" carbide bit.
I’ll take another day to hunt, and if I don’t turn one up I’ll go with a 1/4" and try widening it with carbide. You would think widening it out 1/16" wouldn’t take long even with carbide. One would hope anyway! Actually…now that I think about it, I’d only have to use carbide to get the widening started. Once I have a recess of the right diameter, I could switch to my 5/16" core bit. Hmmm…
We’re going to get this yet. Hang in there guys! 
I need to get a diamond grinding plate for my roto-zip to flatten out a starting point to work from so I can get things nice and centered too.
Anyone have a drill press to donate to the cause? 
Well, still looking. 5/16" is roughly 8mm for our purposes (7.9375mm to be exact), in case someone finds it in metric.
Wow. I just called an engineering firm. They’ll custom make me a bit that they guarantee will do the job in 1 minute, 2 minutes top, and keep me perfectly square to the top of the ball every time.
$180. Ouch. So there’s my tradeoff. I have 40 balls here. I owe 3 people for free (as they invested originally), and if I could sell the rest at the right price to cover my investment, I’m not opposed to this, I guess…
So what’s my math here. 35 usable, $2/insert. So I have to make up $70 there.
$180+$70 = $250.
At $20/ball (my time + materials), I would have to have guaranteed sales of 13 balls beyond what I owe people to break even over all, not counting my time.
I’m tempted to do this, but is there REALLY enough interest around here to guarantee I’ll sell 13 above and beyond what I have out there already? I mean really, like you would plunk down $20+shipping right now if I had them ready to go?
I’ll definitely order one in August, which is a ways off, I know… That’s when my new job starts though.
Try checking this site out http://www.granitecitytool.com/showitem.cfm?itemnum=221
It looks like they have both a solid and core 5/16" bit. Though I am not sure if it wold work since it says they are for granite and marble, but I would imagin it would work on glass. It seems like you have to call them anyway though since you cant put an order for the 5/16" bits online. They arent cheap at $62 but its cheaper than the custom made bit.
Yeah, in either case I need to justify the investment. If I’m going to shell out that kind of cash for a bit, I’ll do the custom one. The difference is $1 vs. $2 per ball on the first batch. Not worth nitpicking. If I can’t get 13 confirmed orders, then it’s a waste of time anyway.
We have success! Sorta. I need to deal with the glass chipping (I have some ideas on that) and I’m still not going in 100% square. I built a jig to hold the ball mostly square, but lacking a drill press is what’s killing me now. If I can deal with the issue of the glass chipping, I may break down and get a drill press. 
Okay. Here’s the deal. I broke down and bought a drill press locally for $50.
I now have a consistent, repeatable way to get a centered, 5/16" hole into these balls, and can set the inserts with minimal chipping around the hole (not nearly so bad as pictured above).
The problem I’m finding is that glass has absolutely zero give so far as expansion of the inserts go, and even the most meager expansion causes the ball to split perfectly in two. The ones that I have done already, the insert is pinching toward the bottom are nearly impossible to get on the stick, and if I do, the ball splits. If I attempt to set the insert with a bolt in it, the ball splits.
What this tells me is that despite the fact that the packaging claims it needs a 5/16" hole, the truth is that is really should be slightly larger. I don’t know what the absolute smallest next increment up would be that I can find, but if I can find one that doesn’t widen the hole out too much, but gives enough room to set the insert without pinching it, I could have these on sale this week.
I dont know what size drill bits they make for glass cutting but normally you can find drill bits either by 1/32" or 1/64". So if you can find one, try something thats 11/32" or the smallest size above 5/16" would be 21/64". Although from what I have seen in glass drill bits with the searching I have done, they have gone up by 1/8" or 1/16". So I am not sure you will be able to find something in those sizes for glass cutting, at least not without having it custom made.
Thanks for the head’s up. What I might try doing is widening it using my hand drill and carbide bit. That might be enough to deal with the pinching. Just run the drill and rotate the bit in the hole.
Hm, looks like in the spear head carbide bits you could find an 11/32" bit. I found one hear, which was the first site that came up when I searched for it.
http://www.ceramictiledrill.com/glass_drill_bits.htm
But try you way with the hand drill first and see if its doable that way. Otherwise you may want to look into trying one of those bits to widen the hole.
No more false alarms. I really have it now!
I remade my jig out of composite wood (so as not to rot from the water) and secure it with stainless screws. Cut the base hole with a diamond core bit, then with a quick snapping motion, use a tiny center punch to snap out the core. I then go back and widen out the hole using a 5/16" glass-cutting carbide bit, and VERY gently run a 21/64" standard carbide bit (not a glass cutting one) into the hole, flushing the hole with water constantly. I now have a working top that is perfectly centered ( so far as I can tell anyway), and the insert isn’t pinched. I run the insert in with a bolt in the insert to help set it centered, and to guarantee that there’s no pinching.
Now, I’m partially lying. There is still the tiniest amount of pinching at the very very bottom of the insert, but this is actually a plus. The last quarter turn on it really tightens the ball. You don’t have to crank hard at all and it locks itself into place. I can’t count the number of times I’ve had to tighten a ball top mid-game.
So. I’m going to play-test this one a bit tonight to make sure it holds up to abuse (I don’t want to get sued by people cutting their hands because the ball splits mid-match) and if it does, I’ll run a whole batch this week. I’m going to start an eBay store today or tomorrow too, as I have a couple more dice tops, and something sure to make the stick makers happy - wood ball tops, unfinished. This means the guys making stained sticks can stain the ball top to match if they so desire.
It’s near 100% humidity here right now, and high 90’s. I’m going to go take a shower, and I have to run a package out to the UPS store before they close for the day. After that, I’ll take pics.
Okay. I’ve updated the first post in this thread, and added the appropriate subject in the Trading Post. Finally, open for business.
That’s right folks. I’ve taken pictures, and now I’m selling my balls on the internet. You can have them too. :xeye:
Those whom I owe free balls will be getting PM’s from me in the next few days, allowing them to get first pick on what they want, the rest will get listed on my eBay store.
Hey man great idea! How about a clear quartz or smoky quartz?
All I ask you guys to do is some googling for me. Find the material you’re asking for in ball shape at or near 35mm, and post the link in-thread. I’ve done quite a bit of googling already, and need to finish up the balls I have now so I can fulfill my obligations and recoup my investment. Here I was asking for $5 from 5 people, and I’ve sunk about $300 into this already. 
Time to start making some of that money back!
I can’t imagine where you’d find quartz balls, but by all means! There are suppliers that do balls of all shapes, sizes, and materials. Get small enough quantities of them to be reasonable to order is the trick. That’s why it took me so long to get this pulled together. I was lucky to get suppliers to even call me back, let alone send samples. That’s why I started collecting funds.
I’d LOVE to get someone that does zirconia to respond to me, but I’m constantly ignored. Zirconia is cheap, and for all intensive purposes it might as well be diamond. Diamond tops would plain rock. I also know how to get the holes in those now too. I don’t. Jewelry shops have a special lathe for drilling centered holes into gemstones. I take it to them and let them do it.
Anyway…actually, I guess I’m not off topic. This thread is for talking shop, the other is for buying and selling. So yeah…go forth, and find me materials.
http://www.phoenixorion.com/phoenixorion/crystals1e.htm
Tons of various mineral 40mm spheres including Tiger’s Eye in 18 different colors that are hella cheap compared to the rest.
Nothing like leaving me margin for error there. $35/each. Yowza. I’ll take that up after I clear my current stock, unless someone wants to pay for it and have it shipped to me to do.