Building Arches

[GJak]

What's everyone's preferred method of building Arches out of dry rock? Was considering hammering / grinding some bigger rocks into some semi-circle shapes to give me what I'm looking for in the new aquascape.

Do you guys think that is the way to go or is it easier to just use a bunch of smaller rubble type pieces and build it up that way?

Also do you guys prefer epoxy or some other method of attachment to hold everything together. Any have any experience with those clear polymer balls that soften into putty in warm water and harder again as it cools? Seems like that stuff would be easy to work and maybe harden quicker then epoxy while also drying somewhat clear.

 

[Jeight]

I built my arch using simple Home Depot supplied materials. 1 fiberglass plow marker indicator cut into 3 inch pieces, a 5/16 diamond bit hole saw for tile (cost about 13.00), super glue, and alot of JB Waterweld for potable water.

I made a cardboard cutout of my take layout and started with a 2x 40# boxes of dry rock and a 10 pound box of one side flat base rock.

Really the only way I found that worked was to keep trying pieces till I find the right one and use a channel lock pliers to nibble off unwanted shards on the joints. Once you have the 2 pieces that you want to join drill a hole in each side with the 5/16 bit then put super glue in the holes to pin them together with the fiberglass rods. I suggest gluing one pin letting it set up then the other pin...before I make the final pin glue I mixed up 1-2 packages (sometimes more after initial bond) and put the JB weld on the surface of the joint where the pin is. Smash like a sandwich and use the remaining epoxy to fill in around the joint. After a couple of hours you can add another piece.. I was in no hurry and did one piece a day until I was done.

Edit: My arch splits in the middle so I could get it in the tank the right side will sit up independently which allowed me to get the left side in with out it tipping over and breaking my new tank. The piece in the dead center is not attached to either side so I can move the arch if need be.

 

[GJak]

Thanks, that gives me some ideas

 

[L0stmykeys]

masonry bit 5/16 i think i got a 12" long bit ate lowes for 13 dollars and plow markers as stated before worked perfect for base rock i uses 12" - 14" base rocks basically in their full form so glue was not an option but just try to balance them out so they free stand then after the shape is there use a screw driver and hammer to knock off unwanted parts. i did my arches this way and then brought them rock by rock in considering it was 40 pound sections i cant see myself safely installing them as one. No need for a hammer a drill my trusty old cordless black and decker cordless drilled right thru them just back out the bit remove the sand from the hole and keep the bit cool with a bucket of water. WASH THE BASE ROCKS OFF BEST AS POSSIBLE THEY ARE PACKED FULL OF SAND!!!!

 

[Cmedeiros]

Nice, a friend of mine just built his, he used some stainless steel corded rods and drilled holes into the rock. And used them as pegs. The cord in the pegs keeps the rock from moving around

 

[GJak]

I'm trying to use mostly shelf rock for the arches and it seems I don't have enough depth to the rocks to drill holes and anchor them with the plow guides. Instead of drilling I decided to use a dremmel with a grinding wheel to cut some shallow slots on each rock that I can slip lexan disks into. That seems to be doing the trick. Once the disks keep them from sliding I can add epoxy and a counter balance on top until the epoxy dries. Doing on piece a day until it's built like Jeight suggested.

 

[Cmedeiros]

I'm trying to use mostly shelf rock for the arches and it seems I don't have enough depth to the rocks to drill holes and anchor them with the plow guides. Instead of drilling I decided to use a dremmel with a grinding wheel to cut some shallow slots on each rock that I can slip lexan disks into. That seems to be doing the trick. Once the disks keep them from sliding I can add epoxy and a counter balance on top until the epoxy dries. Doing on piece a day until it's built like Jeight suggested.

Nice good idea!

I’m an artist that carves stone so I have tons of tools that will come in handy like my Foredom set. It’s like Dremel but more heavy duty with a foot Pedal.

It cuts into the rock so nicely.

I’ll post pics once I get my scape done.

What kind of epoxy is reef safe ?