Portable Rock Saw For The Field?

[uncoat]

Recently on a collecting trip I found a intriguing pinniped skull in a 700+ pound concretion.. I'm trying to decided if there is a practical way to go about removing it. I am considering drilling alot of holes with a masonry drill then trying to break and chisel it out. Are there portable rock saws? I imagine if they exist they very heavy and expensive... Has anyone had experience cutting down rock in the field? Any suggestions or ideas?

- Nick

[crinoid1]

Hi uncoat, they do exist. I have a few friends that have 12 and 14 inch gas powered cut-off saws. They usually range from 800-1600+ $ new. I am 17 and have normal overprotective parents (haha, not complaining), so I am not really allowed to buy one of these saws. Although I'm not allowed to buy, I do look at them online. My favorite is the Stihl "Cutquik" 12 inch saw, which should be around 1000$. I have a friend who uses one with great success. There are other less expensive models (http://www.amazon.co...h/dp/B0052SRJ4K). I would not recommend an electric cordless saw of any kind, as you would loose charge before finishing one cut. After buying a saw, you would need to get a dry cut diamond grinding blade. This would work: http://www.amazon.co...d/dp/B000MQQ83U.

I am not sure about how to go about cutting out the skull. I have a 7 1/4 inch corded circular saw I use at home (incredibly, my parents allowed this!). In the Mississippian rocks from down here in Alabama, I cut fossils out of large rocks using 5 cuts. I make a box around the fossil, cutting in about an inch deep. Then, extend 2 of the cuts (parallel ones) maybe 2 inches longer than the others, and make one perpendicular cut at the end of the extensions. After this, there should be 2 (one large and one small) boxes: one surrounding the fossil, and the other sharing one side of the box surrounding the fossil. Next, I take a chisel and remove the smaller box without the fossil in it. In doing this, you make yourself an edge you can put a chisel up to on the part you want to save. I've attached a picture of what this should look like. Then, carefully chisel the square with the fossil on top out using the edge made with the smaller box. Chisel towards the fossil. If you had the cuts like the picture, you would chisel away the right box, and then chisel right towards the fossil.

I hope this was helpful. I am not really great at explaining stuff, so please let me know if something doesn't make sense.

Thanks!

-Crinoid1

[jpc]

I would suggest renting one from your local big tool rental place. A gas powered number with the biggest blade for rock that they have. They may make you buy a blade. A good diamond one can run into the hundreds of dollars... a lot cheape than buying the whole machine for a one time (or two time?) use.

A big rock, huh? Could there be a skelton in that rock?

Edited May 9, 2012 by jpc

[crinoid1]

jpc, I was wondering the same thing! If the skull is in such a big rock and still articulated, is there a chance more might be there?

I also would have to agree with the first part. I know that down here in AL, a saw is a very handy tool to have, but if you don't live in an area with lots of limestone slabs, then renting might be the best option. I would not buy an expensive blade. Usually, I run through blades on my saw about every month, so I've never had a need to buy the expensive ones just to throw them away as quickly as the cheap ones.

Thanks!

-Crinoid1

[TheFossilHunter]

Rent a gas powered saw and rent the blade if tou only need it once. If need several times, buy the blade for $70 on ebay and rent the saw without the blade. You dont need an expensive blade, the cheap blade will last for years unless you cut very hard rocks.

If need to use many times, buy the saw. . I use the saw like that all the time. Let me kniw if you have any questions

Edited May 9, 2012 by TheFossilHunter

[jpc]

c-1... yeah, a skull on the edge of a concretion is a good sign.

uncoat-... Is the nose end sticking out? If so you just might have a skeleton in there. And, I know this may not be what you want to hear, but if so it may be a specimen best left to the experts. In any case, if you do use a saw to collect the skull, definitely keep an eye out for more bones in each cut you make.

[uncoat]

Hi uncoat, they do exist. I have a few friends that have 12 and 14 inch gas powered cut-off saws. They usually range from 800-1600+ $ new. I am 17 and have normal overprotective parents (haha, not complaining), so I am not really allowed to buy one of these saws. Although I'm not allowed to buy, I do look at them online. My favorite is the Stihl "Cutquik" 12 inch saw, which should be around 1000$. I have a friend who uses one with great success. There are other less expensive models (http://www.amazon.co...h/dp/B0052SRJ4K). I would not recommend an electric cordless saw of any kind, as you would loose charge before finishing one cut. After buying a saw, you would need to get a dry cut diamond grinding blade. This would work: http://www.amazon.co...d/dp/B000MQQ83U.

I am not sure about how to go about cutting out the skull. I have a 7 1/4 inch corded circular saw I use at home (incredibly, my parents allowed this!). In the Mississippian rocks from down here in Alabama, I cut fossils out of large rocks using 5 cuts. I make a box around the fossil, cutting in about an inch deep. Then, extend 2 of the cuts (parallel ones) maybe 2 inches longer than the others, and make one perpendicular cut at the end of the extensions. After this, there should be 2 (one large and one small) boxes: one surrounding the fossil, and the other sharing one side of the box surrounding the fossil. Next, I take a chisel and remove the smaller box without the fossil in it. In doing this, you make yourself an edge you can put a chisel up to on the part you want to save. I've attached a picture of what this should look like. Then, carefully chisel the square with the fossil on top out using the edge made with the smaller box. Chisel towards the fossil. If you had the cuts like the picture, you would chisel away the right box, and then chisel right towards the fossil.

I hope this was helpful. I am not really great at explaining stuff, so please let me know if something doesn't make sense.

Thanks!

-Crinoid1

Hey Crinoid, Thanks for the reply and recommendations. This is one of the only times i would need this saw as of now and i don't exactly have a grand or two to drop on a nice saw and blades.. I have heard of using that method of cutting an border then chiseling it out before and it seems to be the way to go. My folks never trusted me with the power tools either.. Your response was very helpful!

jpc, thanks for the suggestion. I will have to call up some local shops and see what they charge. Often when I find larger bones in larger concretions, i do see small broken bone fragments sticking out as well. In this concretion I did not see any associated bones with the skull. Also the size and position of the skull don't seem to indicate a skeleton.

Has anyone had experience with drilling holes or using stakes to split large boulders? I'm thinking if i could split it in half a few times i may be work it to a collectible size.

[Down under fossil hunter]

I have had to do this a number of times in the field and have had a lot of success borrowing a friends 36volt Hammer drill.

I use 8-12mm masonry bits and space them depending on how thick and hard the slab is and if there are existing fractures.

This isn't something that I have to do every time I go out however I haven't had a bad experience yet.

Good luck!

[Fossildude19]

Uncoat,

I saw a neat suggestion on here not too long ago, where someone had retro-fitted a gas powered edger with a diamond blade, and used that for cutting rocks in the field. I thought that was a nifty idea. Ingenious and thrifty - a few hundred versus a grand!

As others have stated, renting would be the way to go for a one time use, though.

You should also take into consideration whether there is more of the skeleton in the boulder. This could affect how you go about the whole process.

Maybe have it looked at by a museum?

Regards,

[Raistlin]

Uncoat,

I saw a neat suggestion on here not too long ago, where someone had retro-fitted a gas powered edger with a diamond blade, and used that for cutting rocks in the field. I thought that was a nifty idea. Ingenious and thrifty - a few hundred versus a grand!

As others have stated, renting would be the way to go for a one time use, though.

You should also take into consideration whether there is more of the skeleton in the boulder. This could affect how you go about the whole process.

Maybe have it looked at by a museum?

Regards,

I can attest to this. It is not my saw and possibly not the same one Tim is talking about.

I have however used a weed eater/edger converted into a saw. It worked great. I was just practicing with it and learning about things but it really cuts awesome. I have an old weed eater I am thinking about seeing if it can be converted.

[PetrolPete]

here is the link to the home made rock saw one of the members made http://lakeneosho.org/TrilobiteTale/index.html

[Empty Pockets]

I just picked up a 4.5" 18V DeWalt Cordless Cut-Off Tool recently and put a diamond blade on it.

Have not used it yet but it will fit nicely in a backpack and by carrying 2 extra batteries I suspect I can do a bit of cutting before killing it.

If the cut depth proves too shallow I plan on removing the guard and putting a slightly larger blade on it Time will tell.

After looking at fossilcrazy's link I have to comment that my cordless solution is suitable for extracting a few specimens that you can readily see. NOT A MAJOR EXCAVATING EFFORT SUCH AS HIS! Ha Ha!!! Holy Smokes!!!

Edited September 16, 2012 by Empty Pockets

[Malcolmt]

I use a ryobi with 2 batteries in the field. I get about 6 minutes of decent cutting per battery. I have a diamond makita blade on it. It will cut just over 1 inch deep . With both batteries I can just get one normal sized eurypterid (6 inch, call the rock 8 inches by 6 incehes) out of the quarry floor. Thank goodness a lot of my fossil friends have real gas powered rock saws. But when no one else is there it will do in a pinch. It is actual quite good for getting trolbites out of matrix that is too big too cart out of the field. I can probably cut out about ten 1 inch trilos on the two batteries.

[Opisthotriton]

Pinniped skull in a concretion? You want to talk to Boesse.

http://www.thefossilforum.com/index.php/user/225-boesse/

[Mattalic]

On 9/15/2012 at 8:06 PM, Empty Pockets said:

I just picked up a 4.5" 18V DeWalt Cordless Cut-Off Tool recently and put a diamond blade on it.

Have not used it yet but it will fit nicely in a backpack and by carrying 2 extra batteries I suspect I can do a bit of cutting before killing it.

If the cut depth proves too shallow I plan on removing the guard and putting a slightly larger blade on it Time will tell.

After looking at fossilcrazy's link I have to comment that my cordless solution is suitable for extracting a few specimens that you can readily see. NOT A MAJOR EXCAVATING EFFORT SUCH AS HIS! Ha Ha!!! Holy Smokes!!!

Know this was several years ago - but how did this/does this saw work in the field? Any good?

[fossilcrazy]

My recommendation for rock saw cutters is be sure to buy a respirator or dust mask too. I do a lot of rock cutting and dust is unavoidable.

The dust that goes in your lungs does not leave. The Silicosis it leads to, is a known disease leading to Lung cancer.

[Mattalic]

My recommendation for rock saw cutters is be sure to buy a respirator or dust mask too. I do a lot of rock cutting and dust is unavoidable.

The dust that goes in your lungs does not leave. The Silicosis it leads to, is a known disease leading to Lung cancer.

IMG_0067.JPG 1 More Pics for electronic frame 2.jpg

That's a cordless? That looks heavy duty! Also - is that a massive flat, perfect shale bed?

[TOM BUCKLEY]

I tried cordless saws and the problem isn't battery life but rather power. The tools aren't strong enough so the battery overheats and shuts down. I use a saw that I made from an old weed Wacker.

Tom

[TrilobiteLou]

I bought a used Stihl TS420 14" saw for $406 off eBay. I also bought a new saw blade rated for cutting limestone for $39 off eBay. The saw runs great. Saw and blade together weighs about 30-lbs so it's not a tool you'll be packing around like you would a hammer. But boy are they sure nice to have handy. Yes, you have to go back to the truck to get the saw and haul it back to the location you need it, but it's nice to be able to cut into the rock to remove the specimen. Before I'd take a picture and leave the specimen. Last time was a specimen of 3 almost complete crinoid that I left behind because the slab was too large to move, too hard to work with a hammer. Yes, the stihl rock saws néw run $1k plus.

[RyanNREMTP]

A rock saw would have been nice at Oliver Creek last weekend.

[kap]

You can find the saws used in pawn shops for about 1/2 price!

[trilobite nut]

Looking at the first post on this topic, I would advise extreme caution and more investigation before buying blades for a rock saw. You must make sure, and the one recommended in that first post does not tell you, what the max rpm the blade is designed for. If your saw spins at 5600 rpm and the blade is rated for lower, you stand the real risk of the blade breaking which could cause very serious injury or death. These saws warrant lots of respect. Do your homework and stay safe. No fossil is worth the damage this machine can do to you as a result of an oversight.

Edited August 26, 2014 by trilobite nut