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Rock Art => Carvings and Sculptures => Spheres => Topic started by: Jhon P on July 12, 2019, 10:19:18 PM

Title: Core drilling
Post by: Jhon P on July 12, 2019, 10:19:18 PM
Got the core drill in operation. Looks like I am going to have to pour a concrete slab for the machine to set on with a drain.
I feel like a kid with a new toy!
 The plan is to cut a dozen or more cylinders than I need to make a jig and do all the preforms at one time so I only have to set the jig up one time. Cutting rainbow oynx ( banded calcite ). It’s pretty soft.
I cut 7 cylinders in about 1 1/2 hr. I think I will do some serpentine at the same time.
Title: Re: Core drilling
Post by: Jhon P on July 12, 2019, 10:20:12 PM
7 4” diameter cylinders
Title: Re: Core drilling
Post by: hummingbirdstones on July 13, 2019, 06:20:48 AM
That is the coolest thing since sliced bread!
Title: Re: Core drilling
Post by: Rustycat on July 13, 2019, 09:42:35 AM
7 4” diameter cylinders
Are going to cross drill the cores you've created?  That would go a long way to roughing them into spheres.
Title: Re: Core drilling
Post by: lithicbeads on July 13, 2019, 09:51:16 AM
Is this a waterswivel , I can't quite see the details ?
Title: Re: Core drilling
Post by: Jhon P on July 13, 2019, 12:15:43 PM
It has a hose attached to it. The water is injected into the center of the bit.
Second cut
Title: Re: Core drilling
Post by: Jhon P on July 13, 2019, 12:16:20 PM
Third cut
Title: Re: Core drilling
Post by: Jhon P on July 13, 2019, 12:19:27 PM
Preform. I wasn’t able to make the 4th and 5th cuts with my makeshift jig. I will cut the four small corners off in the 10” tile saw. I did 13 cylinders and 7 preforms. Now I have to drive to Sacramento for my granddaughters 19th birthday
Title: Re: Core drilling
Post by: lithicbeads on July 13, 2019, 05:22:15 PM
Yes a waterswivel.I like using them .
Title: Re: Core drilling
Post by: Jhon P on July 13, 2019, 06:05:53 PM
👍
It’s well worth the $60 I paid for it even after I spent $60 on wood for a stand and $100 on a 4 1/2” core drill bit
Title: Re: Core drilling
Post by: Orrum on July 14, 2019, 06:42:17 AM
Wow color me jealous!!!
Title: Re: Core drilling
Post by: GoldWood on July 14, 2019, 09:10:47 AM
Wow John, that’s so cool!
Title: Re: Core drilling
Post by: Sandsave on July 14, 2019, 04:43:31 PM
John I know a sphere maker that performs all his spheres with a core drill, do you want his contact info, he might have some tricks.
I used to make rock pots by core drilling the centers out and putting a pot in the hole I found the wear on the bit on harder material would wear the tip out quite fast, so I haven’t persued the core drill preform technique.
If you stick to the softer material like the onyx the bit should last quite awhile.
Title: Re: Core drilling
Post by: Jhon P on July 14, 2019, 08:32:06 PM
I have talked to John Rowland from highland park and he makes core drills designed to cut hard stone.
I was cutting the oynx and serpentine pretty fast. About 10 minutes to cut a 5” cylinder. I tried a piece of the mushroom jasper and I got 1” in ten minutes.
Title: Re: Core drilling
Post by: Jhon P on July 14, 2019, 08:39:56 PM
First from the core machine. The core was 4 1/8” and the sphere turned out exactly 4”
I preformed 7 of the cylinders with the core drill. I only made three cuts. I couldn’t do anymore cuts with my jig I built out of wood. I cut the corners off on the tile saw and trimmed up all the high spots and put them in the machines. The first grind went fast because they were almost round already. I have all 7 round ( run them through the two head machine) and two running in the machines now.
Title: Re: Core drilling
Post by: Kaljaia on July 14, 2019, 09:34:22 PM
Very nice tool and setup! And lovely sphere!
Title: Re: Core drilling
Post by: bobby1 on July 14, 2019, 11:38:00 PM
Where do you get your core drill bits?
Bob
Title: Re: Core drilling
Post by: hummingbirdstones on July 15, 2019, 07:00:11 AM
Awesome job on that sphere.  That core machine sounds like it really saves a lot of time and effort. 
Title: Re: Core drilling
Post by: Jhon P on July 15, 2019, 08:03:13 AM
Hey Bob. I bought that one from Ediamond tools
I am going to order one from Highland Park, they are designed to cut hard stone.
This one did great on the calcite and serpentine but not so good on mushroom jasper

Title: Re: Core drilling
Post by: Sandsave on July 15, 2019, 06:12:13 PM
Keep us informed when you get the other bit, I have two core drills so I’m half way there.
Title: Re: Core drilling
Post by: lapidaryrough on July 17, 2019, 05:11:13 PM
https://www.kor-it.com/product-tag/core-rig
Title: Re: Core drilling
Post by: Ryaly2dogs on July 30, 2019, 05:00:08 PM
Off topic for spheres, but if you start with a cylinder, with a smaller bit you can drill out a hollow cylinder which can make for a nice lamp.  I am already envious!
Title: Re: Core drilling
Post by: Jhon P on August 01, 2019, 12:48:29 PM
That would work with a translucent rock. I have seen that done with honeycomb calcite