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Gadgets, Gizmos, and Dohickeys => What Equipment to Buy and Where to Get it. => Topic started by: drnihili on February 03, 2015, 06:49:48 PM
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While the rock vise on my on Frantom saw works well enough, I'm noticing that it would be nice to have an option that doesn't require having so much of the rock in the vice. There seem to be two basic ideas for something that would grab onto the edges of a cut face. One of them uses four screws to catch the edges, the other uses opposing slots. I'm leaning towards the 4 screw version, but thought I would solicit advice.
What do you like for grabbing slabs?
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I have really good luck with mine that has four screws. I use a dremel to grind small notches for the screws to set into if necessary. The screws can be set out different lengths to reach odd shaped rocks. On the even rocks I take off the top cross bar and just use three screws.
The ones with the wide jaws look to me like they would only be good on a few rocks that are shaped flat on the side you want to clamp. I have not used one so that is just a guess.
Jim
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That was my thinking too, Jim, though I hadn't come up with the idea of dremeling notches.
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This is from a friend of mine who made his own slabber grabber.....
I made my grabber from two pieces of 2" wide 1/4" thick cold rolled steel. I used a milling machine to make the "teeth" in he end of the pieces. The rest is two 6" 1/2-13 bolts. On the gripping end the nut is on the top of the movable piece nearest to the rock. The other end is under the movable piece. This method allows the jaw to clamp the rock and be tightened with the leverage of the movable piece. It gets a tremendous grip with this leverage. I use a dry diamond blade mounted in a chuck to notch the rock with two parallel grooves. These grooves can be done on any side of a rock at any location so you can orient the rock to best utilize the best pattern. You are not obligated to fuss with sawing a flat face to glue onto a board or such. Usually when you try to cut a flat face it can only be done depending on how you can grip the rock in the saw clamps not necessarily for the best orientation. I can notch any rock in about 30 seconds and it takes about as long to mount the rock in the grabber and then a few seconds to mount the gripper in the saw. Much less time than it takes to cut a flat face, find an non-oily board, glue it on and let the glue set up well enough to hold the rock.
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Good point about not needing a flat face with that style, Sara. It looks easy enough to fab. While I don't have access to a milling machine, I bet I could get a good enough groove with the corner of a grinding wheel, or is the precision really that critical in this applications?
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I am not sure as I have not made one. I would think you could make enough of a groove to "grab" the rock.
Have to wait for the ones that know to sign in:)
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Here is one that I built ! It works really well!
(http://i275.photobucket.com/albums/jj287/minkos61/005_zpsbed5fe17.jpg) (http://s275.photobucket.com/user/minkos61/media/005_zpsbed5fe17.jpg.html)
(http://i275.photobucket.com/albums/jj287/minkos61/003_zpsb5dac861.jpg) (http://s275.photobucket.com/user/minkos61/media/003_zpsb5dac861.jpg.html)
(http://i275.photobucket.com/albums/jj287/minkos61/003_zps61ebfcba.jpg) (http://s275.photobucket.com/user/minkos61/media/003_zps61ebfcba.jpg.html)
:coffee2:
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I have a 'factory' made one (4 ss screws) that works superb. I also have some stock that has lots of threaded holes and I will be making one out of that.
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If you can find one of these, they are excellent slab grabbers. Made up until the early 80's, they show up for sale from time to time.
(http://i907.photobucket.com/albums/ac274/jakesrocks/Missing%20agate/New%20Projects/000E1851_zpsabf9c9dc.jpg) (http://s907.photobucket.com/user/jakesrocks/media/Missing%20agate/New%20Projects/000E1851_zpsabf9c9dc.jpg.html)
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What are they called so I can search ebay, etc.?
thanks,
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Do ya one better. Here's the back side with the info. (Bills Rock Shop has long been out of business). W.C. Antoine Slab Grabber.
(http://i907.photobucket.com/albums/ac274/jakesrocks/Missing%20agate/New%20Projects/000E1855_zps47b45525.jpg) (http://s907.photobucket.com/user/jakesrocks/media/Missing%20agate/New%20Projects/000E1855_zps47b45525.jpg.html)
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thanks
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Texas Rocks also made one similar to the one made for Bill's rock shop.
I used to have some made for me that were similar to the bar style but I have sold out of them and cant find another machine shop to make more for me at a reasonable cost. One of these days I might find someone to make them again.
Tony
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I am not sure as I have not made one. I would think you could make enough of a groove to "grab" the rock.
Have to wait for the ones that know to sign in:)
SOS .. you're back. How you been? Haven't heard from you in a coon's age.
TOG
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Here is mine. Two different ways of mounting it.
(http://i931.photobucket.com/albums/ad156/Rockoteer65/Lortonesaw/DSC00006.jpg)
(http://i931.photobucket.com/albums/ad156/Rockoteer65/Lortonesaw/SlabGrabber%20working.jpg)
(http://i931.photobucket.com/albums/ad156/Rockoteer65/Lortonesaw/Comet%20Slab%20Grabber.jpg)
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Here is a photo of my rock gripper in action on an 18" saw.
Bob
(http://i151.photobucket.com/albums/s160/Rocksbob/Rocksbob074/Gripper%2072_zpsrtpac6fo.jpg) (http://s151.photobucket.com/user/Rocksbob/media/Rocksbob074/Gripper%2072_zpsrtpac6fo.jpg.html)
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(http://www.zbestvalue.com/Slab-Grabbers/itm4281.jpg)
The builder also made/makes? a larger version that he sold/sells? on eBay. There was a whole thread on these in the old forums. The one pictured is awesome and is designed for smaller end cuts and a 10 inch slab saw.
The larger one was designed for bigger end cuts and bigger saws.
Edit Update: The guy IS still on eBay! You should get one each of these before he disappears again.
Here is a photo of the larger clamp he makes:
(http://www.zbestvalue.com/Slab-Grabbers/medium-rock-clamp.jpg)
http://www.ebay.com/itm/MEDIUM-ROCK-CLAMP-for-12-to-24-slab-saws-Holds-end-cuts-hard-to-hold-rocks-/231944128776?hash=item3600f28908:g:b1UAAOSwmmxW6XL~
http://www.ebay.com/itm/SMALL-ROCK-CLAMP-for-trim-small-saws-Holds-end-cuts-hard-to-hold-rocks-/231948451424?hash=item3601347e60:g:DocAAOSwyQtV4oeV
eBay Seller
sellstuff61 (109 )
100% Positive feedback
Item location:
Riverside, California, United States
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That's a pretty good buy as I would not part with mine for $45.
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I have one of Tony's. I love it but wish I would have gotten the bigger one. Works great on the 12 but too small for the bigger saw.
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I have one of Tony's. I love it but wish I would have gotten the bigger one. Works great on the 12 but too small for the bigger saw.
What does Tony's look like? Maybe post a pic if you can.
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Glue them (I use JB weld) to blocks of wood. Easier, faster and cheaper.
If working a rare piece use cedar and you can pick off wood by splitting off thin pieces. Clean the last bit of wood and JB Weld with a sander.
Way too much work and possible slips with a slab grabber in my opinion.
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Glue them (I use JB weld) to blocks of wood. Easier, faster and cheaper.
If working a rare piece use cedar and you can pick off wood by splitting off thin pieces. Clean the last bit of wood and JB Weld with a sander.
Way too much work and possible slips with a slab grabber in my opinion.
If I have a valuable end cut of jadeite and it doesn't fit perfectly with the grabber
(Note: You should always start with an end cut with a flat side)
I mark the end cut with a marker at the spots where the screws will touch. I then use a Foredom with a small diamond wheel to cut small grooves at the marker locations. This means I get a perfect or close to perfect solid fit with the grabber.
I have never had a end cut fall off in 30 years doing it this way.
Time to cut 4 grooves is typically about 5 minutes or less.
For less valuable rocks like agates you don't generally need to cut grooves as an insurance since 99% of the time the pieces don't slip if tightened correctly. Note again that I am talking about end cuts with a FLAT surface on one side. Trying to clamp a rock with a rough side against the clamp is problematic and more likely to slip.
I can't imagine using any other method to get the last few slabs off a rough. I also like the Comet design earlier posted. Looks simple, strong and effective. Maybe only slight downside is it takes more time to screw down and tighten.
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Not exactly a slab grabber, but rather a dopping system for cutting odd shaped pieces or flat faced pieces. An oldie but a goodie.
It starts with a vintage dop pot from the Gemstone Shop, now long out of business.
(http://i907.photobucket.com/albums/ac274/jakesrocks/Missing%20agate/New%20Projects/100_0545.jpg) (http://s907.photobucket.com/user/jakesrocks/media/Missing%20agate/New%20Projects/100_0545.jpg.html)
About 2 weeks ago I found this accessory for the dop pot which I've been searching for since the late 90's. This one just happened to be NOS, still in the box with original instructions. These are used by melting dop wax in one of the 3 cups on the right. These cups fit the dop pot for melting. The rock or faced piece to be cut is placed in the appropriate cup of wax, and the dop pot turned off to cool. When cool, the pot is screwed into the larger piece next to the box. This is clamped into the saw vice for slabbing. When finished slabbing, clean the cutting oil off of the piece remaining attached too the dop. Throw the dop & rock nub in your freezer for about an hour and the rock will fall right off of the dop wax.
The 2 wax pots which came with the dop pot will also work with the slab saver system.
(http://i907.photobucket.com/albums/ac274/jakesrocks/Missing%20agate/New%20Projects/000E2236_zpsyipqyzlv.jpg) (http://s907.photobucket.com/user/jakesrocks/media/Missing%20agate/New%20Projects/000E2236_zpsyipqyzlv.jpg.html)
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Another advantage of using JB Weld and wood blocks is the ability to align the cut lines better. For example in cutting a planed stone such as Rainbow Obsidian you want to make the cuts 10 to 15 degrees from the planes in the stone. This is easy with blocks as you can use a miter saw to set exactly the angle you want.....
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I have one of Tony's. I love it but wish I would have gotten the bigger one. Works great on the 12 but too small for the bigger saw.
What does Tony's look like? Maybe post a pic if you can.
Looks like yours. Icky dirty night time picture but basically the same....
(http://i671.photobucket.com/albums/vv74/kgniot0709/2016-05-25-22.28.16_zps6xyoyxem.jpg) (http://s671.photobucket.com/user/kgniot0709/media/2016-05-25-22.28.16_zps6xyoyxem.jpg.html)
I agree with Redrummd though that wood is best for some things... The rest of this baby is going glue on wood. I'm too scared that the screws might chip it.
(http://i671.photobucket.com/albums/vv74/kgniot0709/2016-05-14-20.00.09_zps7dxqthrw.jpg) (http://s671.photobucket.com/user/kgniot0709/media/2016-05-14-20.00.09_zps7dxqthrw.jpg.html)
(http://i671.photobucket.com/albums/vv74/kgniot0709/2016-05-14-19.59.47_zpsp1apzzdw.jpg) (http://s671.photobucket.com/user/kgniot0709/media/2016-05-14-19.59.47_zpsp1apzzdw.jpg.html)
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Redrummd is a wise old owl. Grabbers will nick your blade if they can. I only tried to get close once......oops. I like the block of wood when I want to get close. Somebody talked about a quart milk carton and plaster of paris????
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Rocketeer - Yes, a milk carton and plaster of Paris for slabbing smaller cobbles where you are not concerned about the orientation of the cuts. Pour a 2 inch foundation into the cartons and let it harden for the area to clamp: fill the rest with the stones you want to cut and plaster; clamp and cut. The stones rather easily separate from the plaster after cutting the "slabs".
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I would agree that charoite probably works better with the wood idea but this is an extremely rare example of a rock that breaks and splinters if you look at it wrong. Plus how many times will you even have a block big enough to slab? It's expensive. Maybe Larimar would be another example but I don't buy that pain in the ass rock either.
I suppose anything can be justified with a unique example but for me 99.9999% of the time my slab grabbers do the job faster and better than messing with glues and sticks.
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I would agree that charoite probably works better with the wood idea but this is an extremely rare example of a rock that breaks and splinters if you look at it wrong. Plus how many times will you even have a block big enough to slab? It's expensive. Maybe Larimar would be another example but I don't buy that pain in the ass rock either.
I suppose anything can be justified with a unique example but for me 99.9999% of the time my slab grabbers do the job faster and better than messing with glues and sticks.
I can't even fathom slabbing Larimar! EEEEEK!!!! Not for me, cabbing it is hard enough.
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Grabbers are neither faster or better than JB weld and wood blocks.
I can chop saw 20 blocks and adhere them to stone in way less than an hour AND they NEVER come loose AND you can cut right up to the wood or even through it to get every last bit of the stone slabbed.
Here is a 5 minute 15 degree offset block and JB Weld layout. Try doing this with a slab grabber.......
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Once you pay for a grabber there's no more money you need to spend.
No extra money for glue and no more money for sticks and blocks of wood.
Grabbers are cheaper and also less messy.
As far as running all the way up to the block that is only an advantage if you need to get a final slab that is less than 1/4 inch thick. A slab grabber properly used and aligned works well to make slabs. It's not the equipment's fault if you get greedy and cut your screw heads off because you cut too close.
Lastly in most cases you don't even need to take the grabber out of the vise using my type. You can unscrew the top and insert another end cut so yet another time saver.
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Thanks for all the great ideas. I only have a tile saw and I'm really looking for how to get the first flat cut on a rock so that I can have a flat side on the bed of the sliding table. I tried a piece of plywood with 4 carriage bolts through that and then 2 1x4's, each with 2 bolts and wing nuts. Like I saw somewhere on the forum. It works ok fine for large rocks, but poorly with small rocks, especially irregularly shaped small rocks. Sounds like JB weld is the next thing to true. You all are great to share. Thanks