Lets find the better ways how to drill our rocks.

[3rdRockFromTheFun]

My bits arrived today. Not sure if I just got a bad batch or if you have a special touch, but those things were delaminating on me like crazy. When I finally got one that kept it's skin it did go quickly through the rock. I just went all the way through one side. Did lots of testing and this is quite viable because the blowouts are so minor that a simply beveling of the hold removes them.

[rocknroll]

  yeah, the quality control is less than desirable (i've seen a few bits with no diamond at all!), but overall, they're still working well for me and seem the cheapest option...sometimes i get 3 cabs out of a bit, and sometimes less than 1.   

[3rdRockFromTheFun]

It's too bad - I do like the shape and the incredibly small size of the entire bit along with the price. These would be excellent for detail work in carving if they wouldn't delaminate like that.

I kind of wonder if most don't come in excellent condition and those are the ones dentists get - and maybe the rejects go into another pile that goes to eBay resellers 

I cannot even count the number of times I have bought things on eBay that were obvious store returns (boxes taped shut and fingerprints all over the inner tape - item barely works or not at all). I've had a little better luck with Amazon for some items but - I guess in the end it's all about cost and if it takes buying three instead of one but those three are a total of 10 percent the cost as the single higher quality item, you win (it's just a pain in the ass is all).

[Helene]

Saw this thread start a few days ago, and was estatic to see it, only now had a chance to read and re-read it.  

The utrasonic drilling method is a concept I had not heard of.  Read threw Franks notes three time and just have an idea of the process, but doing and reading are two different things.  The cost may be too high for just needing five or six holes drilled each month.  What I am trying to say, is when your knowledge of a certain method is vary small, its harder to grasp the method.

I don't mind it taking 10 to 15 minutes to drill a hole that is about 5 mm deep.  My delema is with these new designs I need to drill holes up to 1 1/2 inches deep.  Been thinking of cutting the rough in half, flattening one side, making a channel on each half, then epoxy them back together to create hole.  Afterwards grinding and polishing the bead.

Plan on doing this in June.  Will post how well it works out.  You could use a different material on each half and have a reversable bead.

I have had good luck with Lokipi bits and think the price is good.

[3rdRockFromTheFun]

Seems like somehow, somewhere, somebody has had to have come up with a better way of doing this - other than using microscopic hughes style oil drills with the rotating triple wheel heads...

I'm wondering if this wouldn't work with bits that have sintered heads? I've never heard of such a mini-ster but the only other thing I can think of would be teensy tiny (but loooong) core bits, again - if they make such a thing.

I also keep kicking around the idea of using diamond powder or paste on something like wood (I've tried it with bits and it chews the head of the bit faster (muchly so) than the rock. I was surprised to read someone was using grit like this - but hey, if it works it works.

Okay... now my gears are whirring... what about bamboo skewers (the kind you buy at the grocery store for kabobs) for the pushing/turning mechanism; olive oil for the fluid; 80 to 100 grit for the cutting and a small modeling clay dam around the hole - with the hole itself being started with another bit to a depth of a couple or three mm? I may everything to try this ... if so I'll give it a whirl and report back. If not maybe someone else can try it or educate a fair guess as to the outcome. Only thing is I think it would work better with a slow speed rotary device - all I have in that dept are dremel tools. Still... worth a shot maybe... Oh - and I already know if you go too high with the grit it just polishes (very nicely I might add - got the idea from Pete and I've been using it to polish the bevels of my holes recently even - very slick).

The ultrasonic drills sound like a really cool idea turned into a super pain in the cushion in real life. I suppose if you have lots of drilling and you get the thing adjusted to last for enough holes it'd be worth it. For the onesee twosee person like me it would be probably be quicker if I used a Shawshank rock hammer to get through the rock.

Sorry, I'm tired. I drivel on when I'm tired... blah blah blah blah...

[Helene]

Rio Grande Jewlery Supply sells tiny, tiny 1 mm and smaller diamond bits with a hollow center.

[Allen]

Drilling was a pain for me but for now all is well.

The secrets of drilling as I have found them.

1/ Submerge the stone in water, maybe a little coolant such as cool ant will help.

2/ Use a drill press ( It keeps the drill in line and even pressure can be applied.)

3/ Use a small drill maybe 1.2mm flat bottomed drill, if you want it bigger it can be easily enlarged (drill diameters can be to small and not hold the diamond or to big and overload the drill m/c).

4/ Use wood under the stone

5/ The biggest secret, the drilling pressure is critical as well as getting coolant to the drill cutting edge.
I tap the drill press handle as though I have Parkinson's. The pressure on and off allows coolant in and the hole is completed in good time.

I use a cheap set up. The drill press was $35, the high speed rotary drill set including 60 drills etc was $23 from my local hardware shop, a old meat tray contains the water.





The hollow center drills cut well, a problem is they can block up with the cut material.

Hope this helps somebody.
 

[Enchantra]

Allen, that is a brilliant setup!  I love it!   

[3rdRockFromTheFun]

Drilling was a pain for me but for now all is well.

The secrets of drilling as I have found them.

1/ Submerge the stone in water, maybe a little coolant such as cool ant will help.

2/ Use a drill press ( It keeps the drill in line and even pressure can be applied.)

3/ Use a small drill maybe 1.2mm flat bottomed drill, if you want it bigger it can be easily enlarged (drill diameters can be to small and not hold the diamond or to big and overload the drill m/c).

4/ Use wood under the stone

5/ The biggest secret, the drilling pressure is critical as well as getting coolant to the drill cutting edge.
I tap the drill press handle as though I have Parkinson's. The pressure on and off allows coolant in and the hole is completed in good time.

I use a cheap set up. The drill press was $35, the high speed rotary drill set including 60 drills etc was $23 from my local hardware shop, a old meat tray contains the water.





The hollow center drills cut well, a problem is they can block up with the cut material.

Hope this helps somebody.
 

I LOVE that press Allen - where did you get it?

[3rdRockFromTheFun]

Rio Grande Jewlery Supply sells tiny, tiny 1 mm and smaller diamond bits with a hollow center.

Wow - with hollow shanks even!

http://www.riogrande.com/Product/Diamond-Core-Drills/349040?pos=4

Have you ordered from them before? Have you tried these bits by chance? Thanks!

[Allen]

Being an Australian my English structure may be a little out.

I have tried the hollow core drills and found problems with them blocking up.

The drills I have had the best results with in recent times are 1.2mm flat bottom diamond drills, I buy them from a local supplier at less than $1 each. They come from USA. I expect to drill at least 12 agate cabs per drill.

My hardware shop is Bunnings, in USA a Walmart or its equivalent may carry something similar. The press and drill (10,000rpm) were made in China (where else)

[3rdRockFromTheFun]

Well I can tell by the design of that press (the holder for the tool is the same piece that goes directly to the guide post) that as long as there's not too much play (as long as the drill and the guide are secure enough) it should drill quite straight and consistent.

I gotta find one of those...

My press is over-complicated and while I can get it to go pretty straight it has a little too much play in it for my tastes (due to the overcomplexity - a fixture on a guide bar that has another guide bar on it upon which a carriage rides that carries the tool... geez, c'mon... 

[3rdRockFromTheFun]

p.s. I do not have course enough grit to try the experiment I mentioned. I'll order some but it'll be awhile - so much going on in my life I think I'm going to pop a sprocket any minute...

[Helene]

Have you ordered from them before? Have you tried these bits by chance? Thanks!
[/quote]

I have just to try, but had problems with breakage, I put too much pressure on the bit.  I have not used them enough to give you a solid answere.

[3rdRockFromTheFun]

Thank you Helene - mainly I wanted to make sure I could trust them with my credit card number (never ordered from them before) - sounds like they delivered so okay by me.

Allen - here is something close to what you have I think (minus the drill)

http://www.ebay.com/itm/7-16-Collet-Rotary-Drill-Press-Dremel-Stand-Bench-Table-/160793051423?pt=LH_DefaultDomain_0&hash=item257003411f

He has a lot of measurements there - but I don't see one for the hole that holds the drill, lol - I'll have to ask. Simple as it looks I like the idea of the main guide and tool being directly attached rather than a whole separate guide.