LS-12: the Volkswagen bug of slab saws

Without a slab saw, the lapidary is left with cutting other people's slabs to make preforms.  Without a slab saw, the surprise of finding out what's inside a rock becomes something only imagined.  That is, unless you have a trim saw for cutting the small stones.

I was probably 2 to 3 years into my middle-aged lapidary obsession. My trim saw was getting a workout and I was longing for something to cut some of my bigger rocks.  The catalogs I had acquired for all the big names in lapidary were dog-eared and stained from frequent consult. Unfortunately, I'm not a man of means who can drop several large on a fresh cutting machine.

Browsing the Craigslist is how I found most of my other equipment, and it's how I came to own such a saw.  I wasn't really looking for anything in particular, just a deal that was within my tiny budget. Can I just say it now, that used lapidary equipment keeps it's value. Or at least all the folks looking to part with their equipment seem to think it does.

One fine Saturday, I spied a new listing for a Lortone LS-12.  The asking price was about a Franklin north of my current cash stash, but I stuffed my pocket with the green and took the hour-long drive to Circle City.  First off, I've lived in Arizona for 30+ years and I'd never heard of Circle City.  It's essentially a manufactured home (not necessarily mobile) community that is layed out in concentric circles with a park in the center that resides in the desert between Phoenix and Wickenburg. My guess is that it was some developers utopian dream for retirees of little means.

I'll call him Earl.  I think that was his name, but I don't remember. He lived on the outermost circle with a beautiful view to the southern desert expanse. Creosote and high tension wires for as far as you could see.

Earl was a prospector, probably somewhere between 40 and 105 years old. Prospecting is hard on a body so I don't rush to assumptions.  He led me into his backyard and into a tent with no sides where his lapidary shop was. There, on a folding table was the husk of a Lortone LS-12. The old kind, pre powder blue vintage. Parts were strewn about. The lid was on the ground, seized motor, no belt, pulley shield under a few tools and a half cut piece of mushroom rhyolite in the vise.  Not exactly what I'd envisioned on the drive out.  My heart sunk a little but I wasn't out yet.  We struck up a conversation about rocks in general and found we had some common interests.  He told me about his claims out by Wickenburg and stories of old ladies filling the back seat of their Cadillacs with his rough.

It came time for negotiation, and I felt that I had some leverage given the condition of the saw.  Before I even countered his asking price, he lowered the price and said he'd throw in a new motor that he had sitting on his kitchen table.  Somehow he knew exactly how much cash I had in my pocket because his offer was within $10 of what I had on me.  That said, I couldn't leave well enough alone, I insisted that he throw in some of the mushroom rhyolite that he had lying around.  It was a deal!  I handed over the cash and loaded my basket case saw into the back of the grocery getter and headed back to civilization.

Never having used, let alone owned a slab saw, I studied my pile of obviously well-used lapidary parts.  I moved the parts that appear to be moveable and sort of took inventory of steps I would need to take to make the saw functional again.  I would need a different motor bracket since the new motor was different, and I wanted to re-attach the lid where the hinges had broken off.  After a saturday afternoon pin-balling off of appliance part shops I found the motor bracket, and a small piano hinge would work for the lid.

Earl claimed that he only used Lube Cool, a water based cutting solution. I over-ruled Earl on this one and went straight to mineral oil. Two tidy gallons of horse laxative in the pan brought the level to the cutting part of the blade.

For the maiden voyage I wasn't going to mess around.  I had some large chunks of rainbow petrified wood that I wanted to slice.  I clamped one piece in and flipped the power switch followed by the feed. In a minute or so, the blade made contact with the stone and my first cut was under way! I didn't really know what to expect, nor what most cutters considered success.  I was cutting rock and that's all that mattered to me.  In fact I would go so far as to say I abused the saw in un-natural ways.  I was creatively mounting boulders that had no business being in a 12" saw.  I learned that if you don't have a good clamp on the vise, rocks shift mid cut and if I was lucky, would only bind up and kill the motor.  Or worse case, a twisted rock would bend the blade and I would be hammering it flat again on my shop floor.  I can hear the purists out there cringing by my antics, but hey, I was having fun, and getting slabs!

In the desert, the cutting season is between October and April.  Reason being, the saw stays out in the shop, and the shop has no HVAC.  Each fall I clean out the old sludge and oil and put clean oil in the pan.  As I learned more about the saw, and the physics of cutting stone, my imagination ran with my questionnable skillset as a backyard engineer.  Parts wore out and needed to be replaced. Fortunately, the LS-12 hasn't changed much in the 60+ years of production, and parts can be sourced from many locations.  Not only that, but like the VW bug where parts could be exchanged with your lawn mower, I found alternatives to the factory design of the LS-12.

Stay tuned for part 2 where I convert my VW slab saw into the Millenium Falcon!