Electric Powered Arrastra

[desertgolddigger]

I'm curious about if say an Arrastra with two 100 pound grinding stones could be powered with a low rpm high torque geared electric motor.

I saw Gold Tramp's Arrastra, and was very impressed at how it could pulverized gold ore.

Is there an alternative to an Arrastra? I think I saw two stone wheels in a pan that was run with an electric motor. I doubt I could afford such a machine, but am just curious.

I am just trying to explore a more efficient way to grind ore. The chain mill is fine, but not all that efficient.

 

Amazon Forum Fav 👍

Upgraded Night Vision Monocular Digital Infrared Monocular Telescope for 100% Darkness with 8X Zoom - Grab it through Amazon!

[Assembler]

Make stone mill with Stone,Hand-made stone mill collection

Some interesting technics.

 

Amazon Forum Fav 👍

Treasure of Victoria Peak - Grab it through Amazon!

[desertgolddigger]

Make stone mill with Stone,Hand-made stone mill collection

Some interesting technics.

Interesting, though not useful for ore grinding. If you're a Master Stone Mason, then you probably could create a base stone with a track in it, and a couple of stone wheels to make yourself a wet pan mill, maybe a meter in diameter run on an electric motor.

 

[Assembler]

Interesting, though not useful for ore grinding. If you're a Master Stone Mason, then you probably could create a base stone with a track in it, and a couple of stone wheels to make yourself a wet pan mill, maybe a meter in diameter run on an electric motor.

Most Senior Centers will have rock saws that you can use for a small fee.

Just keep in mind you should use basalt rock to make a harder grind mill and very thin grooves in the face of the stones that any one can grind simple straight lines / grooves with an angle grinder with cut off wheel.
Keep it simple.

 

[N-Lionberger]

Most Senior Centers will have rock saws that you can use for a small fee.

Just keep in mind you should use basalt rock to make a harder grind mill and very thin grooves in the face of the stones that any one can grind simple straight lines / grooves with an angle grinder with cut off wheel.
Keep it simple.

I would use granite like the old timers basalt is way too soft for grind stones Grinding grooves in arastra stones sounds is a fools errand. Only chance a senior center will have a rock saw is if they have a lapidary shop which is fairly rare these days outside of better equipped art centers and gem and mineral clubs. Majority of lapidary saws aren’t big enough to make grindstones…

 

[desertgolddigger]

Where I live, our senior center has Bingo, a pool table, and they serve lunch. They also do some crafts, but they don't have funding for things like power equipment. The city takes care of the grounds maintenance.

Some people fail to realize that small towns like mine have bare necessities. Anything other than that, I have to travel 140 miles roundtrip to get. For example, to get my blower motor overhauled, is 160 miles roundtrip. We just don't have the amenities of cities. If it weren't for the Marine Base here in 29 Palms, this town would probably dry up.

I agree that a granite type rock would be best for the Arrastra. Gneiss is a granite, which we have in abundance out here. The problem is that the Arrastra base requires rocks about 12 inches thick, and then you have the two 100 pound rocks attached to the drag bar. That's a lot of weight to haul home. And I would have to chisel everything to shape.

At my age, and with my arthritic hands, it's not going to happen. I will just have to be happy with my chain mill. I just ordered more chains from the security company that carries them. They cut five feet of chain into 5 link increments for no cost. Shipping is included. A pair of chains is about $16.

 

[Assembler]

I would use granite like the old timers basalt is way too soft for grind stones Grinding grooves in arastra stones sounds is a fools errand. Only chance a senior center will have a rock saw is if they have a lapidary shop which is fairly rare these days outside of better equipped art centers and gem and mineral clubs. Majority of lapidary saws aren’t big enough to make grindstones…

You can look up where there are lapidary places that are open to the public in many bigger cities.

1/64" deep grooves main function is to spread out the materials faster over the surface area. The grooves will need to be added as they will quickly wear down. Almost anyone can grind the grooves when needed. Remember keep it simple as you are not reinventing the wheel here.

If you want go use any rock that is readily handy in your locale as most rock will still work if you are comparing it to cast iron etc. The cost is so low that you should make a number of them to park around the areas that you work in the most.

If you double the cut of a 16"-28" rock saw you can make a grind stone that most single people have a hard time keeping up with. People around the world have been doing this for the last 200 years or more.

As far as feed holes in the rock that you use why not make more then one hole for feeding materials.

 

[Assembler]

Where I live, our senior center has Bingo, a pool table, and they serve lunch. They also do some crafts, but they don't have funding for things like power equipment. The city takes care of the grounds maintenance.

Some people fail to realize that small towns like mine have bare necessities. Anything other than that, I have to travel 140 miles roundtrip to get. For example, to get my blower motor overhauled, is 160 miles roundtrip. We just don't have the amenities of cities. If it weren't for the Marine Base here in 29 Palms, this town would probably dry up.

I agree that a granite type rock would be best for the Arrastra. Gneiss is a granite, which we have in abundance out here. The problem is that the Arrastra base requires rocks about 12 inches thick, and then you have the two 100 pound rocks attached to the drag bar. That's a lot of weight to haul home. And I would have to chisel everything to shape.

At my age, and with my arthritic hands, it's not going to happen. I will just have to be happy with my chain mill. I just ordered more chains from the security company that carries them. They cut five feet of chain into 5 link increments for no cost. Shipping is included. A pair of chains is about $16.

Why not pay someone in a larger city to cut some rocks for you?
Do you have any friends or family members that could cut some rocks for you?

Go to HF and buy a utility trailer to mount your grind stone set up with electric motors / gas engines on to help you run your grind stone set up.

 

[desertgolddigger]

Why not pay someone in a larger city to cut some rocks for you?
Do you have any friends or family members that could cut some rocks for you?

Go to HF and buy a utility trailer to mount your grind stone set up with electric motors / gas engines on to help you run your grind stone set up.

Nope, All my core family and my friends have passed on I'm all that's left. I'm not going to invest in a trailer. If I were to build an Arrastra, I would do so in my back-backyard. But I don't plan to currently. I'm investing in spare hardware for my chain mill.

 

[N-Lionberger]

You can look up where there are lapidary places that are open to the public in many bigger cities.

1/64" deep grooves main function is to spread out the materials faster over the surface area. The grooves will need to be added as they will quickly wear down. Almost anyone can grind the grooves when needed. Remember keep it simple as you are not reinventing the wheel here.

If you want go use any rock that is readily handy in your locale as most rock will still work if you are comparing it to cast iron etc. The cost is so low that you should make a number of them to park around the areas that you work in the most.

If you double the cut of a 16"-28" rock saw you can make a grind stone that most single people have a hard time keeping up with. People around the world have been doing this for the last 200 years or more.

As far as feed holes in the rock that you use why not make more then one hole for feeding materials.

Typically lapidary shops that are open to the public like you describe are usually in city art centers which in this day and age are rare. The only one I know of here in Northern California is the Richmond Art Center. They have largely downsized their lapidary department as not many people in the jewelry classes are interested and few people are left standing that know how to use the machines. The largest saw they possess is a 14” chop saw. I own the same saw and you would be hard pressed cutting blocks of granite with it. Lapidary saws aren’t meant for such applications they are for cutting slabs or preforms. There are lots of gem and mineral societies that have lapidary shops but they are typically for members use and they are very protective of their slabbing saws you can’t just show up out of nowhere in either scenario expecting to be able to run a bunch of granite through a slab saw, it’s not realistic, nor is expecting someone’s family and friends to have that ability. Arrastras don’t have feed holes through the rocks… you do know what an arrastra is and how it works right? People have been grinding ore with them for thousands of years. You don’t need a rock saw to make them just a means to drill the holes in the drag stones or “mullers” to chain them to the drag bar. You seem to throw a lot of ideas at a wall hoping they will stick it’s kinda crazy, the more I read about how AI operate has me wondering.

 

[N-Lionberger]

Nope, All my core family and my friends have passed on I'm all that's left. I'm not going to invest in a trailer. If I were to build an Arrastra, I would do so in my back-backyard. But I don't plan to currently. I'm investing in spare hardware for my chain mill.

His suggestions have always been…. Almost all of it is not plausible. Having looked at a few arrastras out in the back country I can confidently say you do not need 12” bed stones and you also do not need 100lbs drag stones you can get away with much smaller and also the fit of the stones does not need to be super exact. You do not need a rock saw to make an arrastra. I have ideas concerning making my own small arrastra utilizing a right angle gear box I scrapped from a large motorcycle. I figured on using a series of belts and pulleys to bring down the speed of a small gasoline engine. I like to power my equipment with propane. It’s cheap to convert an engine and you will never deal with carb issues ever again. Though not arrastra related I love it on my dredge it’s impossible to spill gas/dissolved oil in the creek and I can run all day without refueling which improves fine recovery, I’m a propane motor fanboy for sure lol. I hope gold tramp’s health improves he is a very knowledgeable fellow and with his arrastra kept some old time tech alive. I work on a stampmill with my ECV chapter I’m a nerd for the old skool. Arrastras are very slow in grinding but does it very well. I’m interested in building one as my recovery of hard rock ores is an interesting hobby while my placer activities have turned into a job. The enjoyment of pulling a rock from the earth and getting some colors from it is unique

 

[desertgolddigger]

Typically lapidary shops that are open to the public like you describe are usually in city art centers which in this day and age are rare. The only one I know of here in Northern California is the Richmond Art Center. They have largely downsized their lapidary department as not many people in the jewelry classes are interested and few people are left standing that know how to use the machines. The largest saw they possess is a 14” chop saw. I own the same saw and you would be hard pressed cutting blocks of granite with it. Lapidary saws aren’t meant for such applications they are for cutting slabs or preforms. There are lots of gem and mineral societies that have lapidary shops but they are typically for members use and they are very protective of their slabbing saws you can’t just show up out of nowhere in either scenario expecting to be able to run a bunch of granite through a slab saw, it’s not realistic, nor is expecting someone’s family and friends to have that ability. Arrastras don’t have feed holes through the rocks… you do know what an arrastra is and how it works right? People have been grinding ore with them for thousands of years. You don’t need a rock saw to make them just a means to drill the holes in the drag stones or “mullers” to chain them to the drag bar. You seem to throw a lot of ideas at a wall hoping they will stick it’s kinda crazy, the more I read about how AI operate has me wondering.

Based on all the photos I've seen of very old Arrastras, I tend to agree. The big thing is building the basin as flat as possible. Then you just need a few large stones, choosing the flattest sides to use for grinding against that flattish surface you created. Drill anchor holes on the two stones to attach to the drag bar, and you're ready to go. All you need is some kind of motive force to turn the drag bar at a slow but steady pace, around and around the basin you created. The key is that motive force. with a gas or electric powered system, you'd need some kind if gearing, or pulley system to knock down the rpms to basically a walking pace.

I understand the basics. It's just putting something that eventually weighs several tons together, and that's just for an Arrastra that is probably only four feet in diameter.

 

[desertgolddigger]

I did a little more reading, and it seems the ancients used metamorphic rocks for grinding stones. Apparently they are created under immense pressure, and are extremely hard. Probably one reason they are used in countertops, building facings, and gravestones.

 

[N-Lionberger]

Based on all the photos I've seen of very old Arrastras, I tend to agree. The big thing is building the basin as flat as possible. Then you just need a few large stones, choosing the flattest sides to use for grinding against that flattish surface you created. Drill anchor holes on the two stones to attach to the drag bar, and you're ready to go. All you need is some kind of motive force to turn the drag bar at a slow but steady pace, around and around the basin you created. The key is that motive force. with a gas or electric powered system, you'd need some kind if gearing, or pulley system to knock down the rpms to basically a walking pace.

I understand the basics. It's just putting something that eventually weighs several tons together, and that's just for an Arrastra that is probably only four feet in diameter.

Yeah you can’t mount that on a harbor fright trailer lol..

 

[N-Lionberger]

it doesn’t even need to be that flat it will take care of itself.

 

[Assembler]

Typically lapidary shops that are open to the public like you describe are usually in city art centers which in this day and age are rare. The only one I know of here in Northern California is the Richmond Art Center. They have largely downsized their lapidary department as not many people in the jewelry classes are interested and few people are left standing that know how to use the machines. The largest saw they possess is a 14” chop saw. I own the same saw and you would be hard pressed cutting blocks of granite with it. Lapidary saws aren’t meant for such applications they are for cutting slabs or preforms. There are lots of gem and mineral societies that have lapidary shops but they are typically for members use and they are very protective of their slabbing saws you can’t just show up out of nowhere in either scenario expecting to be able to run a bunch of granite through a slab saw, it’s not realistic, nor is expecting someone’s family and friends to have that ability. Arrastras don’t have feed holes through the rocks… you do know what an arrastra is and how it works right? People have been grinding ore with them for thousands of years. You don’t need a rock saw to make them just a means to drill the holes in the drag stones or “mullers” to chain them to the drag bar. You seem to throw a lot of ideas at a wall hoping they will stick it’s kinda crazy, the more I read about how AI operate has me wondering.

From mid valley to Portland Oregon there must be 10-35 places where one can either go to work with rocks and if the work can not be done there many people will out of there homes for a cost. One can even put out adds out for someone to cut rocks for them. All you need is one or more people who will do it for you and the money to do it.

Some Senior Centers will have diamond saws as big as 20"-24" in size and will charge by the inch (some by the time) that you cut etc.

A number of different rock types will work for grinding stones. If you have a good source for granite use it as needed.

Arrastras can be heavy compared to the grinding stones shown above and there is little problem transporting a small set of grinding stones.

Your point about "AI" is only as good as the training input for the "AI" to work with and the "AI" can just stall if the "AI" comes across a "program" that is not in it's training. Go take a look at what some people in the Military have done to stall / not function right "AI" systems. Some of this is "Military grade AI" keep in mind.

 

[Assembler]

Yeah you can’t mount that on a harbor fright trailer lol..

I have seen abandoned arrastas because it would cost to much to move them again.

A smaller grinding stone set could be mounted on a small utility trailer within reasonable limits with a electric motor / gas generator for power set up.

The advantage of moving the grinding stones on a trailer is to move the set up where noise / dust is not an issue.

 

[Assembler]

I did a little more reading, and it seems the ancients used metamorphic rocks for grinding stones. Apparently they are created under immense pressure, and are extremely hard. Probably one reason they are used in countertops, building facings, and gravestones.

After you wear out your first grinding stone set you can pay someone to make the next one out of the rock type you want.

You could try putting out a Craigs listing or other add to see if someone is getting rid of there damaged granite countertop material. Some people may be moving away from this material because of trace natural radioactivity.

granite countertop radiation - Google Search

 

[russau]

Any community college or state college or university that has a Geology Department will have rock saws and if you take a class there and get to know the professor , you can usually work out some sort of deal to use their saw or someone there could do it for you... Try that !

 

[Assembler]

Interesting, though not useful for ore grinding. If you're a Master Stone Mason, then you probably could create a base stone with a track in it, and a couple of stone wheels to make yourself a wet pan mill, maybe a meter in diameter run on an electric motor.

Most of the work is to make the flat surface that the rock saw will cut for you. Drilling the steel pin hole and feed holes can be done with either diamond or silicon carbide depending on the rock material.
No channel or outer groove is needed just a catch pan or container for the milled material.

Any community college or state college or university that has a Geology Department will have rock saws and if you take a class there and get to know the professor , you can usually work out some sort of deal to use their saw or someone there could do it for you... Try that !

Yep and there is a lot of community colleges around. Some will charge as little as $30.00 for a class and cutting cost will likely be on top of the cost.

One Senior Center I looked at charged as little as $10.00 per class and the cutting costs will be added for the final cost.

Remember both the community colleges and Senior Center will have a lot of people who have equipment at home and will cut rocks for you.

 

[desertgolddigger]

Any community college or state college or university that has a Geology Department will have rock saws and if you take a class there and get to know the professor , you can usually work out some sort of deal to use their saw or someone there could do it for you... Try that !

I see no point in doing that. Out here in the desert there's plenty of rock that's calved off the hillsides. It's just a matter of finding some that have flat surfaces. The stones don't need to be perfectly flat anyway. I imagine the old time Arrastras didn't have perfectly flat surfaces. They just needed to be fairly close.