# Lapidary 3 head sphere machine



## JoeSixPack74 (Dec 10, 2013)

So this will be my second time building a lapidary 3 head sphere machine.  For those who don't know lapidary is the working of stone, mineral or gemstone into jewelry or decorative items such as spheres.   This right here is the first machine I built several years ago.  I used a hacksaw, welder and drill press.  It is a fairly basic and standard diy machine.   Commercial units can cost between $400-2500 this one cost me $75 to build.




The way it works is you take a rock.  Cut it to a cube.  Next all the corners are cut off.  Once that is done you rough grind it to as close to a sphere as possible.   The stone is now put into the machine and ground down with 80 grit.   Followed by 220, 400, 600 and finally polish.  Here is a picture of a sphere being ground with 80 grit.




This old machine is huge and way overbuilt.  My goal is to create a smaller machine and one machine for each grit.  Also I am using this to hone my skills on the lathe and mill.  And a final goal is to also in the future sell kits after I convert one of my X2 mills to CNC, but that is in the future.  So to start I turned some .375" thick by 2.75 diameter disks.  I will need two of these per machine.




I just used a bolt as a mandrel.  It worked fine and I made 4 of them at 2.75 and only had one mistake.




My three legs on this machine will be made with 8020 aluminum extrusion.  These disks will be used for the center hub.  I am using the rotary table to make 1" wide cuts 1/8" deep for each leg.  




This is one of the hubs completed.  Only 3 more to go for two machines.




Here is one base complete and the components for another.  Two of my completed spheres are in the picture.  On the left/back is Sodalite and on the right is Florida rock.  It is also known as fossilized coral/limestone.  I acquired that piece from a Burger King in Naples, FL.  Next I will start working on the heads.  




Hopefully in the next few days I can get some of the other items done.


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## Charley Davidson (Dec 10, 2013)

Very cool, I wish guys like you would not show me all this cool stuff, I have enough hobbies:whiteflag:


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## MedfordChris (Dec 11, 2013)

That is a way cool machine!


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## Charley Davidson (Dec 11, 2013)

Joe, I bet you've been up by my parents place where they have a big wholesale rock show in between Sylva and Franklin, NC. There's tons of rock stores here too.


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## JoeSixPack74 (Dec 11, 2013)

Thanks guys, I have had a fascination with how things get made.  Working with stone once you get into it is kinda just like anything else.  Except for poking around Florida a bit I have not been out of state rockhounding.  I do most of that on eBay.


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## JoeSixPack74 (Dec 14, 2013)

Here is some progress. This is one of the heads laid out.  Have not gotten around to cutting it as of yet.  That is blue Sharpe marker as layout dye.  Have Monday and Tuesday off and will get to them then.




In the mean time I got a package in the mail from OshPark.  A couple weeks ago I drew up a schematic and board in Eagle CAD.  This PWM motor controller is using a 4093 IC for a timer to trigger a IRF510 MOSFET.




These are the 6 boards I received today.  They use a purple soldermask as that is their trademark.  I used to use BatchPCB but they closed and referred everyone to OshPark.  I actually like OshPark better, a little bit more cost wise but better customer service.




Here it is soldered together.  I ordered 6 and only need 3-5 of these.  Hopefully the MOSFET I put in can handle all 3 motors on the head at the same time.  If not I can use one for each head then one for the water and another for the grit feeder.  The boards I created can be used with an on board potentiometer or a header connected to one.  Same for the LED.  That power supply on the left is the first thing I did on the milling machine in 2006.  It is a regulated +5/+12 500 mA power supply that I designed and etched.  Still have the CAD files for it.  For years I used it on the old sphere machine to power 3 computer fans.  It has served me well.




Next thing for this little board it to make a heatsink for the MOSFET.


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## JoeSixPack74 (Jan 5, 2014)

Have not had much time lately due to work and my temporary 3pm to midnight shift.   People are breaking my ATMs faster than I can fix them.  Anyways I was able to machine the pins that the heads will pivot on.  They are made from some 1/4-20 bolts.  One side is left threaded and the end is turned to .160".  That part will go into a bracket yet to be made.  






Hopefully this Wednesday I can work on the brackets since it will be my only day off for 2 weeks.


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## Bill Gruby (Jan 5, 2014)

Every small part is one step closer to the finished project. Very nice work.

 "Billy G"


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