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Don't try this at home

Slick

Slick

Well-Known Member
I have all these Stockmines laying around and figured a sectioned one would look spectacular. So I got out the hacksaw and commenced to strokin' away. For naught. Barely scratched the surface. So, out comes the sawzall. With a new blade installed. Was optimistic. Ha! Same-same results. Just cut through the tape and scratched it. Sheesh! Called a buddy with a power metal saw and he agreed to the attempt with the caveat that I buy a new blade if it mucks it up. An $80 one. Passed. Next up; the side grinder. Had a used "blade" in it, and went at it with that. Success! Sort of. Have already replaced with a new disc. Which cuts considerably better. I have two more new ones in the wrapper but not so sure it will be enough to make both cuts. Throw in the need for a face sheild and dust mask and this is turning into quite the chore.
I have cut into it about 1/2" or so. One can see the matrix. It is one of the hardest materials I've ever had the pleasure of trying to cut.
May take a day or two to get it where I want it, but I have a goal. Hopefully, it'll be worth the effort.
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I've got a metal chop saw, which I'm going to try next. I also have concrete discs for the side cutter, but suspect they won't be effective on the steel bits.
 
As kahu! said, you can buy concrete cutter discs for side grinders. Most hardware stores have them, you may need several as they wear down quickly in hard material. Do it outside and defiantly wear face/eye protection, gloves and a mask. Good luck!
 
That's not the problem. As soon as you start grinding, these small pieces of steel , cast in concrete become red hot, and crack te concrete with their heat. Furthermore, after so many years, some pieces of steel near the surface have started rusting and expanding, pulverising the concrete around it. Another problem with cutting is that steel is tough, and concrete is hard. You'd need a grinding disc that can cut both, and they do not exist.
I found out the best way to make a cutaway model is by keeping the original mine complete, and making a replica of plaster of paris, glueing pieces of steel to the cutaway surface.
The only way you could cut it is by waterjet, but that will be an expensive trick

Regards, DJH
 

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I was thinking along the lines of a commercial concrete/rock cutter.they cut through rebar.
The blades have slots that assist in removing the dust that clogs other blades (looks like the problem you've got),and water to cool and remove the sludge.
 
kahu1 said:
I was thinking along the lines of a commercial concrete/rock cutter.they cut through rebar.
The blades have slots that assist in removing the dust that clogs other blades (looks like the problem you've got),and water to cool and remove the sludge.
Click to expand...

A commercial machine is expensive, exept when you own one. And yes , it will cut through rebar, but these are long strands, supported by the concrete around the steel , and not 10mm long pieces that will be ripped out of the concrete when the slot hits them.
Believe me, I have tried to saw and cut them too in the past, without succes....

Regards, DJH
 
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jeeeensy said:
short message,,,,,,
Stone discs will cut Metal but Metal discs wont cut stone :(
Click to expand...

True, but it will still not solve the problems of the shrappnell pieces becomming redhot and pulverizing the concrete.

Regards, DJH
 
Thank you all.
Jeeeensy is spot on with the disc capabilities. BUT, I did obtain a modicum of success. About half way into the second cut, the bottom quarter "crumbled" away. Soon thereafter, the rest of the section gave way. Spent a little time grinding things flush. The metal disc suffices, but will take a while to get to the lowest crumbed out area. Will go at that tomorrow as the old arms and back are quite tired from manhandling the side grinder half the day. The metal chop saw did not work.
Anyway. here's where I'm at with it. The metal aggregate appears to be pinch cut wire, approx. 8mm dia. and 1cm long.

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Crumbled. My intention is a 1/3 sectioning. Went shy, inside, of that, anticipating a lot of clean-up. It should come out about right once I get the edges "polished".
 
a conrete cutter with a large diamond cutting disc + much water cooling should work (to prevent the effect Pzgr40 has explained). A friend did very smooth cuts through steel reinforced concrete without a problem.
 
Batoncollector:
Yes. I crafted those from 1.25" dowel.

Glevum:
Not sure about the waterjet. It would result in a 1/2 cut, based on what I've seen on TV. Which would be OK, I suppose. Main problem is I know of none in these parts. Hinterlandish out here. Not a lot of high tech anything.
 
Slick, it will not work, and you are wasting a mine that is hard to obtain in the USA.
Realize that the mine was constructed by casting a negative filled with iron scrap, filling the space between with cement (not concrete). To enshure the cement fills the spaces between the scrap from top to bottom, it has to be thin like choclate milk, so obviously not the best quality of cement. It's only purpose is to keep the scrap together in a certain shape for a certain period of time. A certain time as these mines were never meant to form permanent minefields that would last for decades. A bit like the wooden shu mine that was only usable for a couple of months before falling apart.
Cutting this type of concrete mine will simply not work.....believe me. It's a waste of resources and mines.

Regards, DJH

PS; do not throw away the cut out concrete parts and the loose iron crap. You can hammer the loose pieces of concrete to get the iron scrap out and use it when you descide to make a replica out of plaster of paris , either cement. You than glue it to the cut surface like in my replica concrete mine.
 
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I would imagine too, that the steel that was used was of very unpredictable hardness. Years ago, there was a guy up in New Hampshire that made a lot of repro Ordnance items for collectors. He would turn out projectiles or fuze-looking nose plugs on his lathe, and he would take ordnance for his collection in trade for his work. He was always using questionable materials, so instead of buying aluminum bar, he would cast aluminum, and it was so bad it looked like a sponge. He got some steel one time that had come from Poland, and it had hard spots in it. I tried to bore out the inside of a repro 35mm projectile, and all it did was burn up the end of the drill bit. I finally gave up on hollowing it out.
 
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