a bit off the subject of detector equipment, Trimmer test! UPDATE!!

KingTotsalot

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KT has been looking for a medium sized rock trimmer for months now, and has discovered that since the advent of Covid, not even the Chinese are making them. Harbor Freight has a table model A-Frame Shop Press listed on line, but it too is out of stock. But KT kept looking and managed to find the same one, different name (the Chinese do that a lot!), in stock on line with Home Depot, so He ordered it. It is rated 6 tons. It is a bolt together unit and some folks in the ratings stated it is too flimsy, well I do not think they bothered to tighten the bolts down sufficiently. Once I get it put together, and all squared up, I will take it to a welding shop and have them weld the joints together. The press rod will be cut off a sufficient distance and a steel chisel welded on, along with another chisel end welded onto the steel plate that the press rod works against.

I started the basic assembly last night and am only hand tightening all the bolts presently.

Anyway with those mods, it should work ok and I will only be about $150 total into it. I have my small one for detailed trimming but this should be able to do a controlled break on a 3" to 4" thick rock. Anyway, here are some pics for your examination.
 

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KT has been looking for a medium sized rock trimmer for months now, and has discovered that since the advent of Covid, not even the Chinese are making them. Harbor Freight has a table model A-Frame Shop Press listed on line, but it too is out of stock. But KT kept looking and managed to find the same one, different name (the Chinese do that a lot!), in stock on line with Home Depot, so He ordered it. It is rated 6 tons. It is a bolt together unit and some folks in the ratings stated it is too flimsy, well I do not think they bothered to tighten the bolts down sufficiently. Once I get it put together, and all squared up, I will take it to a welding shop and have them weld the joints together. The press rod will be cut off a sufficient distance and a steel chisel welded on, along with another chisel end welded onto the steel plate that the press rod works against.

I started the basic assembly last night and am only hand tightening all the bolts presently.

Anyway with those mods, it should work ok and I will only be about $150 total into it. I have my small one for detailed trimming but this should be able to do a controlled break on a 3" to 4" thick rock. Anyway, here are some pics for your examination.

Wow, only about $150 total into it ?

Now I am not knowledgeable about rock cutters but that seems like a bargain for something you can modify to be a rock cutter !

Keep us updated on how well it works once finished.

.......just remember the old carpenter's adage: "Measure twice, cut once" :laughing:
 
Wow, only about $150 total into it ?

Now I am not knowledgeable about rock cutters but that seems like a bargain for something you can modify to be a rock cutter !

Keep us updated on how well it works once finished.

.......just remember the old carpenter's adage: "Measure twice, cut once" :laughing:

HA HA, yep KT knows that one! Yesterday a friend of mine from Church came by the Castle....he is a retired machinist....and he not only approved of my changes, but also gave me the name and telephone number of a local welder who lives in the community just north of me. KT had forgotten about him, but he did some work for His Highness a few years back. He welded up a tip trailer for KT so it would not tip anymore! HA HA It still works fine!

After checking around with several hardware stores, KT finally found 2 1" chisels at Home Depot. So they are marked and ready to take to the welder to be cut off. The plates that came with the press are just way too heavy and thick, so KT ordered a 3/8" steel plate 4" X 6" rectangle from eBay.

So it will be a few days before KT can get all the parts assembled and to him to alter, but I will worry about that after the 4th of July. :D:D KT thinks the steel plate will be here by mid-July.

Happy 4th to everyone!
 
Some progress today on this project. KT has it built, and did some measuring. KT took the push rod today and the 2 chisels to a welding shop today. The welding shop man cut off the chisel heads and cut off the push rod to the proper length. Then welded one of the chisels to the push rod. He also cut a 5/8ths collar for the other chisel head to fit into from a piece of iron pipe. Once back to the Castle, KT spent a little time painting the push rod and worked on the collar. The 2nd chisel head was a bit floppy in it so KT got a piece of 1/2 copper pipe and cut a sleeve for the bit to fit in and worked on the sleeve so it is a snug fit inside the collar! Once the lower metal plate comes in from eBay, I will have the collar welded on dead center on the plate.

Tuesday morning the 5th of July, KT will meet with his local welder, have him true up the frame and weld it so that even if the bolts work their way loose, it will not move! Complete assembly will be completed after KT paints all the welds and the paint dries! Should be able to post a picture of the completed unit shortly afterwards.
 
Interesting project, i'd be curious to see some more pictures as you get it modified.

Thank you, zeemang, for your interest! Here is a photo of the rock breaker as it presently is....bolted together and push rod with chisel added, painted red. The unit as it stands is ready to have many of the seams and joints welded so it will not loosen up during use! That will be done Tuesday morning. You will also note to the left sitting on a metal plate is the collar and sleeve with the other bit inserted. The plate KT ordered will supposedly be here Tuesday, who knows for certain?.....and when it arrives the collar will be welled in the center of it. That will allow His Majesty to position it under the push rod bit. KT is still trying to decide exactly where the completed unit will be mounted "permanently". After the collar is welled onto the new 3/8" plate, the entire top of the plate will get a coat of paint....presently thinking bright yellow or same color red as the push rod. The lower chisel will not be painted. As it sits in that sleeve, it can be rotated as needed for whatever piece KT is breaking.

The hydraulic jack has some bit of tension on it as it sits, but can be raised easily, enough to fit a 4" rock into the space between upper and lower chisels, so this unit is capable of breaking a 4" diameter rock, or smaller.

Have a great 4th of July!
 

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Two more minor alterations….

KT decided He did not like the long handle instead of a two piece handle, especially since it did not fit properly in the jack pump mechanism and would be hard to store for transport….the pipe was just slightly too large diameter..that is a problem with cheap stuff! Ha ha. Anyway KT found a 3/8th inch extension bar and the right diameter socket to fit nicely. Bernie the welder will make that combo into a solid unit. And then KT took a piece of 1/2 inch copper pipe and cut a length of 12 inches, cut notches in the end of it fit the pressure release mechanism on the jack base, and taped the handle end. The socket extension slides inside the copper pipe so it is much more compact. KT is thinking of attaching a piece of capped 3/4 inch PVC pipe to the side of the press to store the handle set in! Finally, KT realized that because everything is black, it was hard to see the pump release, so it was painted white! The next photo, coming on Wednesday, will show all these mods!
 
Unless you are able to cut on both sides of a rock, I doubt that you can get a controlled break on them. To do it good you need a rock saw.
 
Completed rock breaker project

Below are pictures and a relatively complete explanation of what KT has now built for a rock trimmer.

It took His Majesty two evenings in the Royal Man Cave, playing with the basic assembly because it all bolts together. So it can be a bit floppy before everything is aligned and welded!

First there pictures that show the basic unit assembled and some of the modifications KT did to it.! His Majesty purchased 2 1 inch wide masonry chisels from Home Depot.! They were expensive at $17 each, one to have welded onto the vertical push bar on the bottom of the jack plate and the other to fit in a collar to be welded to a lower plate.! KT ordered the lower plate from eBay....3/8ths inch steel plate measuring 6" X 4".! Two plates came with the unit but were 1" thick and His Majesty wanted that extra 5/8ths inch of opening.! We took the first bit of parts to a welding shop and they cut the chisels off square and cut off the push bar by their total cut length (2.25"). Then had them weld one to the push rod so the chisel edge was oriented to the length of the push rod plate.! Then KT painted the push rock red so it could seen better.! And the same welder cut a 5/8th inch internal diameter steel collar from a piece of pipe for the bottom chisel to fit in.! It was a bit floppy so back at the Castle KT located a copper water pipe and cut off a 5/8th inch piece using the Royal Dremel tool, then sliced it lengthwise and cut out some of it to make a snug sleeve for the lower chisel to fit in.! Materials and labor cost was $40.! His Majesty wanted the bottom chisel where it could rotate, if needed.

After doing a bit of measuring, we decided to leave out the middle horizontal guide bar (see the original picture on the box at the first of this thread) to gain space...and by doing so, KT can now readily fit a 4" piece of rock into the space.! When examining other people's builds of similar units of bearing presses, His Majesty had noted that several folks had left off that lower guide bar.

Then the unit was taken to a second welder!and all the bolted joints welded for increased strength and stability. He also welded the collar on the lower plate and the socket on the end of the new jack handle. This cost me $120, slightly more that the cost of the unit, but KT does not want anything loosening up with usage.!!

Finally, here are pictures of the upper and lower portions of the unit, a close up of the two chisel edges showing the alignment.! His Majesty made a new jack handle and pressure release pipe.! The unit came with a 30" handle and KT did not like that it was in one piece as a 30" lever might allow someone to overload the capability of the unit. Also the darned pipe did not fit the jacking mechanism hole due to a factory oversight.! The receiver was slightly egged, likely during its manufacture.! So KT found a 12 inch rachet extension and located the proper sized socket to fit in the jacking mechanism welded to the extension....that eliminated any play in the new handle.! To make a! release device, I took another piece of copper pipe and cut off 10" of it, used my dremel moto tool with an abrasive wheel to cut two slots opposite each other in the end.! Wrapped the other end with some Gorilla tape.! When His Majesty found these two items nested together, KT took a spring clip from the Royal Workshop and bolted it to the right side of the frame to store the nest handles together.

After running it up and down a couple of times, KT aligned the lower chisel in the welded collar on the lower plate (centered) to the chisel on the end of the push rod, and clamped it down with some 1" C-clamps from Home Depot....$2.25 each.! He has ordered some 2 inch spring clamps from eBay...6 for $8 and free shipping, to replace the lower C-clamps on the bottom plate...They should hold it nicely and be less in the way.! KT also C-clamped the jack to the upper push bar plate for added stability.! If there are no problems with it, then they may just be removed.

KT has already learned you do NOT want to keep any tension on the bottle jack as was done, because a small leak at the top of the jack has started.! His Majesty only had about 3 strokes of pressure, and have cleaned up the few drops that leaked, and tested the unit and it still works fine and does not leak, but would if it were left with any pressure for some time on the jack head. That is worth noting.! Finally, there are many short 12 ton and larger tonnage jacks that would fit this unit rather than trying to rebuild the seals if they do blow out.! They run about $50 for shorty hydraulic jacks on eBay.

KT has slightly less that $300 in the entire breaker, a bargain considering, if available, a German Zuma, would have cost around $1000, and His Majesty was unable to find any manufacturer in the USA making a specific rock and mineral trimmer of this size.! A friend showed KT a picture of his unit, made from a 5 ton stand press and it is a box frame, but has had the same modifications done to it that KT did to this one, and his is NOT portable, whereas this one is, weighing in at around 50 pounds, and fitting readily in the back of the Royal Coach!

To break a rock of any size on this unit, for operator safety, it is necessary to use a dishrag or shop towel to wrap around the piece once you have it set in the jaws.! Pieces can explode out of it like grenade shrapnel if the rock is very brittle.! Also wear safety glasses.! One of my friends suggested I attach formed Plexiglas on both the front and back to prevent this, but a towel works just fine.! Also wear some work gloves because rock shards can be razor sharp for some types of quartz.

Enjoy the pictures!
 

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To further reply to graybeard's comment, KT is looking to break rock, not saw rock. Breaking rock exposes tiny cavities filled with interesting minerals under a microscope. Sawing rock destroys said cavities and fills them with lubricant if they happen to be exposed, creating a hassle to clean. Dust caused by breakage can readily be blown off the surface.

But thanks anyway for your comment, graybeard. People who collect micro minerals just do not want to see a sawn surface on their specimen...With larger pieces, sawing is sometimes necessary because the crystals themselves may be very delicate and wholesale removal of excess matrix will improve the value of a specimen. But most mineral collectors will not consider anything with a sawn surface as a high dollar specimen, just because there are so many specimens out there to chose from, why pick one that has been sawn.
 
Wow, only about $150 total into it ?

Now I am not knowledgeable about rock cutters but that seems like a bargain for something you can modify to be a rock cutter !

GLK, this was a bearing press, and it was a bargain at that price, but alas, His Majesty way underestimated the cost of welding and labor, so KT wound up with a bit over $300 invested, but that is still cheap compared to a commercially made rock trimmer, if one can be found! And that is the hang up, since the start of Covid, KT has been unable to locate anyone building these from scratch.
 
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The spring clamps KT ordered.....

finally came in today, so here a pictures showing their use and replacement for the small C-clamps that were shown in the last series of photographs!
 

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Neat KT, congrats on the finished product, sometimes if you want something both useful and economical you need to do some modifications yourself !

No big hurry, but later on maybe show some examples of "before and after" with some of the rocks you cut.
 
Neat KT, congrats on the finished product, sometimes if you want something both useful and economical you need to do some modifications yourself !

No big hurry, but later on maybe show some examples of "before and after" with some of the rocks you cut.

Yes, GKL, once I get hold of something big enough to use it, I will give a photo by photo demo! One thing tho, once the rock is locked into it by some pressure on the chisels, I will definitely wrap the sample in a piece of an old towel, just to prevent shards from flying! KT is not interested in having a Royal Eye put out! :laughing::laughing:
 
OK, the first test of the 6 ton Rock Trimmer.....

Revealed a problem, but KT knows how to repair it.

First the actual test... in pictures.

Pic 1 shows a piece of north AR limestone with a face of calcite crystals and a few small pyrite crystals scattered about. The stone is set in the opposing 1 inch chisels.

Pic 2 shows the specimen wrapped with cloth to prevent rock pieces from flying.
However it was at this stage that KT discovered a flaw in the design. As KT began to apply pressure with the 6 ton jack, it began to slide on its base plate.
THAT will be corrected by bolting the jack base to the plate....likely some minor disassembly will be required. After repositioning both the Jack and the upper chisel, KT discovered that the lower chisel plate also wanted to slide...those dinky clips were not sufficient to hold the plate in place. So after a second repositioning. KT again began to apply pressure and POP, the rock broke just as KT had wanted it to. Over 1/2 of the waste rock was removed....shown in 3rd picture.

Then KT moved the specimen to the small screw trimmer with 1/2 inch chisels. Pic 4 shows the specimen with the trimmer, Pic 5 shows the speciment set in the trimmer ready for pressure, and Pic 6 shows the final results....sorry they are a bit out of focus...but there are 2 thumbnail pieces and 1 miniature as the end result. The reason for this trimming stage was simply to remove some of the damaged surface of the mineral face. One can never know if everything will go as one wants! The larger piece did retain the 3 pyrite crystals, and the other two small pieces show orange fluorescence in LW UV 365nm light due to included petroleum in the calcite.

KT thought people would like to see these initial results. More to come after doing the modifications to the plates listed above in the discussion.
 

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Revealed a problem, but KT knows how to repair it.

First the actual test... in pictures.

Pic 1 shows a piece of north AR limestone with a face of calcite crystals and a few small pyrite crystals scattered about. The stone is set in the opposing 1 inch chisels.

Pic 2 shows the specimen wrapped with cloth to prevent rock pieces from flying.
However it was at this stage that KT discovered a flaw in the design. As KT began to apply pressure with the 6 ton jack, it began to slide on its base plate.
THAT will be corrected by bolting the jack base to the plate....likely some minor disassembly will be required. After repositioning both the Jack and the upper chisel, KT discovered that the lower chisel plate also wanted to slide...those dinky clips were not sufficient to hold the plate in place. So after a second repositioning. KT again began to apply pressure and POP, the rock broke just as KT had wanted it to. Over 1/2 of the waste rock was removed....shown in 3rd picture.

Then KT moved the specimen to the small screw trimmer with 1/2 inch chisels. Pic 4 shows the specimen with the trimmer, Pic 5 shows the speciment set in the trimmer ready for pressure, and Pic 6 shows the final results....sorry they are a bit out of focus...but there are 2 thumbnail pieces and 1 miniature as the end result. The reason for this trimming stage was simply to remove some of the damaged surface of the mineral face. One can never know if everything will go as one wants! The larger piece did retain the 3 pyrite crystals, and the other two small pieces show orange fluorescence in LW UV 365nm light due to included petroleum in the calcite.

KT thought people would like to see these initial results. More to come after doing the modifications to the plates listed above in the discussion.

Neat KT !!!!

Reminds me of how I read about geodes being cracked open. (though I think they usually do that with a hammer if I remember correctly)

I know it nice when a gadget you make (or modify) works as hoped, I think in the past I had an occasional homemade gadget that worked as hoped and some that didn't, but it was usually stuff mostly made with odds and ends I already had so no big expense involved if it didn't work :lol:

Very glad you thought in advance to wrap the sample in an old towel to prevent shards from flying, that is something you'd definitely rather not learn is needed by mistake !
 
Neat KT !!!!

Reminds me of how I read about geodes being cracked open. (though I think they usually do that with a hammer if I remember correctly)

I know it nice when a gadget you make (or modify) works as hoped, I think in the past I had an occasional homemade gadget that worked as hoped and some that didn't, but it was usually stuff mostly made with odds and ends I already had so no big expense involved if it didn't work :lol:

Very glad you thought in advance to wrap the sample in an old towel to prevent shards from flying, that is something you'd definitely rather not learn is needed by mistake !

Nowadays, most people who crack geodes at rock and mineral shows use a plumber's cast iron pipe cutter mounted on a stand. It has circular teeth embedded along a chain which wraps around the geode. So every inch or so around the diameter of the geode the chain cutters apply pressure evenly and it splits nicely (usually) along that line. Hitting with a hammer is a hit or miss proposition at best, due to the lack of even pressure and the impact, and yields unpredictable breakage patterns.
 
Some minor alterations to the existing rock breaker, needed after the first use. The hydraulic jack was bolted to the base plate so that it cannot slide around. And the lower plate was drilled and bolted to the rail on which it sits, after aligning both chisels. Pictures will be taken later and added to this comment soon! :D
 

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C mon King, we know those are your dungeon torture devices for unruly subjects trying to overthrow you and sieze your throne!:lol:
 
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