Old Prismatic faceting machine

[johnful]

Hi Debbie,

Much like on your machine, the old motor was modified by having two notches cut in it.

The new motor is slightly longer and it looks like I will need to notch it like the old one.

I'll send some more pictures when I get it mounted.

J

 

[johnful]

Hi Debbie,

On another note, it looks like you have that retro machinist's lamp as well. The shield around the bulb is a bit rusted and some paint is missing on mine. I was thinking about cleaning it up and using high temp paint to refinish it if I can fined a matching color. The goose neck is in pretty good shape with no missing paint or rust spots.

 

[johnful]

More questions/notes.

When I checked the driver roller to wheel ratio, for each turn of the motor the lap make 1/4 turn. This means that with a 3500 RPM motor, the maximum speed that it will turn is 875 RPM. There's a variable speed controller (Minarik MA62) on mine just like in the picture of your machine. I've never found the need to run 100%, and always end up in the 40% to 50% range in the past.

The dops I originally got the machine (I inherited it in 2008) were aluminum and I don't think original. Many of them were bent. My dad had obtained the machine in the early 80s used, and was not the original owner. I really don't know exactly how old it is. In any event, I have a set of Graves dops but they are not keyed. The quill will take keyed dops, but I have not found any that look like the aluminum ones that came with it. What kind of dops do you use, and where did you get them if I may ask?

Thanks

J

 

[Debbie K]

J:

I've been using Graves dops, but I have a full set of the aluminum ones that are keyed for the quill on the Prismatic. I'll take a picture of them tomorrow as it's late here right now. Mine came with the machine, but I understand that they can still be obtained from Zane on the Polymetric website. He also has many of the replacement parts like the cheater which I ended up fabricating, as I'm cash poor and my time is my own and it wasn't that difficult to make, so I figured what the heck.

In my opinion, the only really poorly designed things on this machine are the angle brake, the placement of the lamp and the height adjustment for the water tank. The brake is the worst part. The lamp is impossible to position in any way that gives me a good view of the stone. I'm considering drilling out on the left side of the base and moving it if I can. Mine's a little rusty, too. The water tank is rickety and I plan to modify it to be sturdier and may move it to the right hand side.

I really wish this were a left handed machine, but that's just a personal preference on my part. I learned on a Graves and got used to it and am having a difficult time adapting.

Thanks for posting the info re: the motor. I know it'll come in handy for any of us who may have to replace one in the future.

Will dig out the dops and post pictures tomorrow.

Debbie K

 

[Debbie K]

J:

Here's a picture of the dops and the 45 degree holder. All the dops have a rounded end like the holder does. The three on the front left for the emerald cuts have no grooves.

Debbie K

 

[johnful]

Hi Debbie,

Those look like the dops that came with mine. The set was incomplete and several had been ground on. My dad, toward the end, had macular degeneration and couldn't see too well. I'll ping Zane and see what he has.

You can detach the lamp; it's held on by a single bolt. I did that and found an era base which I attached it to. Now it is independent of the machine and a lot easier to move around for lighting angles.

I have the original water tank and it is definitely wobbly. A bolt goes through a hole on the side of the casting of the tank, with a nut under that to hold it tight in whatever position. there's another nut on the bold above where it bolts into the machine frame. You screw it in, tighten the lower nut, then loosen the top nut to position the tank. Once the tank is positioned, you tighten the top not. I find this very clumsy, so I'm looking at alternatives that still fit within the look and feel of the machine and reuse the cast aluminum tank.

The hard stop is a little wonky, but I've gotten used to it. Mine seems to work fine.

Zane had mentioned in email that my mast had a "quick height release". Apparently this is relatively rare. Your mast appears to be the same as mine from the first photo you posted. Could you post a larger picture of the mast only on your machine?

Thanks

J

 

[Debbie K]

J:

Part of my problem with the drip is that my "master lap" is a corian lap which is probably thicker than real ones. The tank was too low and I put on a longer bolt which helped a little, but I'm not happy with it.

Did Zane say anything about how the "quick height release" worked? That would be really cool if it were the case, it would save a lot of time. It does look like we have the same machine in almost every way, which is weird because it's not really shown on the polymetric page or anywhere else that I looked. If you need better pictures, let me know and I'll post them.

My machine is on a painted plywood base, so it would be no problem to drill a hole and move that lamp. It's in exactly the wrong place right now; it shines in my eyes, not the stone.

Debbie K

 

[johnful]

Hi Debbie,

Worked on it a little bit today, but will likely get it going tomorrow. I had to do a little grinding on the frame for the new Leeson motor to fit. I'll ping Zane about the "quick height release" feature. I really don't know what it is or how it works. Your machine looks exactly like mine. I'll take more pictures tomorrow. I inherited mine after dad passed away in 2008. He bought it used in the early 80s, so I don't really know how old it is. I think it's a great project to refurbish this old machine and keep it going. I'll likely buy a new one (I'm not cash constrained, I work for a silly-con valley company), but would like to get this one going and keep it for nostalgic reasons. The fact that Zane thinks it's rare makes it all the better. I got into faceting after I inherited this machine. I cut a 100ish gems before the motor went out. It's clearly a dying art. In honor of dad, I'll keep it going just a little bit longer. I have a huge pile of rough that I also inherited to keep it going.

J

 

[Debbie K]

J:

I really don't know if you are going to find a faceting machine that is much better than this one is; I grouse about the worn out and broken parts on mine, but when everything is working properly I don't believe any other would be much more accurate. The mast is fantastic, the table is machined to be absolutely level and everything is relatively easy and straight forward to adjust. The protractor is one the best manual ones out there; and some models had a dial angle finders on them that I believe attached on the empty area of the rod next to the brake that the head pivots on; Zane may have some of these in stock also. I have considered getting a digital one, but honestly, at this point the things I am making are so basic that it would be wasted on me.

Even when it wasn't working properly, it was apparent on the very first stone I cut on it that I was getting absolutely flat facets, something I assumed I was getting on my other machine but wasn't. When the brake is working properly, the mast arrangement makes it very difficult to over cut as it doesn't bend as much as others do. I've done a patent search trying to find this mast as I was looking for an exploded view because I thought I might have to replace the bearings, and couldn't find it. UltraTec, one of the best machines out there, has a very similar mast.

Honestly, the only thing I would change about this machine would be to add a reversible engine. I haven't yet encountered a stone that I think I needed to use this function on, but I know they are out there. If I didn't have this machine, I would want the one that Lefty has as it makes sense to me. http://www.vjfacet.com/Products_VJ_Facet.html

Please let me know what Zane says about the quick release; it sure would save a lot of time. Since you wrote about it, I've looked at mine and couldn't see anything that looked like it would release the height adjustment, but sometimes I'm just incredibly dense.

I got some aluminum last week and am planning to make a new brake and upgrade my cheater; the plastic is working but I think metal would be better. If and when I do, I post photos.

Debbie K

 

[johnful]

Hi Debbie,

The motor has two wires, red and black. It's a DC motor, so to reverse you switch them. I could have sworn that before replacing the motor, mine turned clockwise. When I got everything in today, I connected red to red and black to black and it now turns counter clockwise. I was thinking about making it reversible after that. All it would take is the right kind of toggle switch to reverse both wires. I'll look around for one. I'm pretty sure it won't be expensive. Under $10 I'd bet. I'll call the local Grainger tomorrow and see what they have.

The motor was a little "fatter" than the old one. I had to modify the chassis a little bit with a dremil tool and cutting blade. Once I got it all lined up, I used some half inch stainless 8 -32 screws with star washers to mount it.

We'll see how it goes next weekend.

J

 

[johnful]

One of the favorite things I cut with this machine was an amethyst heart. It has a coloration flaw, but I incorporated it into the design. Looks like a mended heart.

 

[Debbie K]

Very pretty! I love amethyst, fortunately I have a bunch of good, facetable grade in almost every tone and saturation of purple.

I found this on Grainger https://www.grainger.com/category/t...ntent&searchRedirect=toggle+switch&sst=subset
I don't know which, if either, would work.

Also, Zane may be mistaken about the quick release on our model of mast. I found this a while back https://www.google.com/patents/US3992821 which does have a quick release function when I did my patent search on the Prismatic months ago. It seems to be based on this patent from 1904 https://www.google.com/patents/US3992821. I never found a patent for the one we have.

Mine rotates counter-clockwise. I thought that was right because it's a right-handed machine; the Graves was left-handed and it rotated clockwise.

 

[johnful]

Hi Debbie,

Still waiting to hear back from Zane on the quick release feature. For the life of me I can't figure out how it works either. He may have been mistaken.

Mine is a right handed machine as well. For the switch, I think it needs 6 terminals on the bottom. in the center, you would connect the red and black wires. on the top, red to red black to black. On the bottom, red to black and black to red. When you flip it up, it would be counter clockwise. When you flip it down it would be clockwise. It probably wouldn't be a good idea to switch direction while it was still turning. I saw one on Grainger for $4.95, but I'll check it out and confirm tomorrow. I'm thinking drill a hole next to the fuse to mount it there.

I'm actually left handed, but learned to facet (along with a lot of other things) right handed.

The Amethyst came from a location about 25 miles from where I live. There's a lot of nice spots to collect amethyst/emerald/aquamarine/sapphire/ruby/tourmaline/epidote/rutile all within an easy day trip from where I live. The strangest find I ever made was in my own back yard. I had bought a bit a gravel for landscaping. After finishing up, I noticed one really clear sort of odd green/yellow stone near the water spigot. Turned out to be a 45ct Topaz. The gravel came from Phoenix City Alabama, where this sort of alluvial topaz is known to be found. I haven't cut it yet. I'll take a picture and post it.

J

 

[Debbie K]

I'm in Houston, no rocks here, except things that have been trucked in. I did happen to find a really good piece of shrinkwood in a bunch of landscaping rocks outside of a nursing home here once. You are so lucky to be able to go rockhounding and pick up something worthwhile; whereabouts are you? The only gemstones near here are in Mason, Texas, about 200 or so miles away; mostly clear topaz if you're lucky enough to find one. Lots of agates near the same area, but the only other rocks near by are petrified wood about 75 or so miles away.

I learned to facet left-handed and am having a difficult time adjusting to a right-handed machine even though I'm right handed. I'm almost ambidextrous; some tasks I can seem to only do with my left hand, like driving and faceting.

I was thinking of drilling out by the controller or fuse, too, if the switch idea would work. I'll let you figure it out as electricity and motors, controllers and switches mystify me. I'm pretty good at mechanical things, just not electricity.

Debbie

 

[johnful]

Hi Debbie

I live in a suburb of Augusta, GA. I'm 45 miles from Graves Mountain. About 40 miles from Jackson's Crossroads. 25 miles from Germany Creek. 40 miles from Long Cane Branch. 60 Miles from Cunningham Farm ... etc... etc... etc... It's a good location to live.

Speaking of Agates, I have accumulated quite a bit of Savannah River Agate over the years. Nice colors and filled with fossil shells. I don't cab much; I mainly collect it as display specimens. The little vugs or cavities are filled with druzy quartz.

Surprises come along all the time. One time about 5 years ago a new road was cut a few miles from where I live. I noticed the material looked a lot like some a bit further north where I had found almandine garnets. I asked the crew if I could have a few pieces and they let me take "as much as I wanted". Turns out it was filled with deep red (almost black) garnets the largest of which was about half an inch in diameter. I have a whole bag full of them and they do look gemmy. I'll cut a few one of these days.

Of course I get out to Graves Mountain frequently. I have a fairly good collection of large rutile crystals. Some are as big as your fist.

J

 

[Debbie K]

One of the most beautiful faceted stones I've ever seen was a rutile https://www.gemsociety.org/wp-content/uploads/2015/02/Rutile-600x610.jpg . Most of the ones I've seen that have any clarity have a red cast to them and don't look like this. Have you ever found one good enough to facet? It would be cool to facet the stone with the highest dispersion of all. I also love the rainbow hematite from Graves Mountain.

I rely entirely on rough that I buy or is given to me. We only have two shows a year that are actually gem and mineral shows; the others are fine minerals and jewelry/bead shows. But we have a fantastic rock club here that is open 4 days a week, and as members die, retire or move, the club will often dispose of their collections. I've gotten some really good rough through my club's sales and auctions.

Have you gone to William Holland? I have several friends that go almost every year. I think they just like the camaraderie; they've taken most of the courses already. They've tried to talk me into applying to teach a carving class but it's such a long drive and it really doesn't pay that well. Carving classes have to be so small to be any good and then they get too expensive for the individuals...

Thanks for the pictures of the Prismatic; when the time comes to replace my motor I won't be too afraid. If you put in the toggle switch please do a step by step; I will probably do the same if it works for you.

Debbie

 

[johnful]

Hi Debbie,

The material from Graves Mountain is very dark. I usually cut a flat back and just cut a crown on it. Very metallic looking. When you cut it, the swarf is red.

J

 

[Wally69]

I am enjoying this thread, lots of new knowledge and a bit of adventure being thrown into the discussion.

Keep it up :Y:

 

[Whisp]

I am enjoying this thread, lots of new knowledge and a bit of adventure being thrown into the discussion.

Keep it up :Y:

You and me both, I love seeing what other people do and how they go about solving problems as they arise. It's great that there are still people that can and do their own thing without constantly jumping into a forum and expecting to be spoon fed for every small thing that crosses their mind.

 

[johnful]

Hi Debbie,

This is the one I found at Grainger. I still have to go pick it up. It's snowing (in the deep south) now, so it'll probably be tomorrow or Friday before I go get it.