Magnetic frag mounts - Page 2

panmanmatt · 01-10-2008, 05:37 PM

Should've known you'd have tried it already.

Nice growth so far.

panmanmatt · 02-02-2008, 01:43 PM

OK I got the large magnets in finally. I went ahead and made up 1 frag magnet and one frag rack so far. The rack utilizes 2 sets of magnets and is capable of holding 24 frag plugs or about 12 frag disks. All my testing for weight so far has been done on a 29 gallon tank. I don't have actually numbers for the weight but you can get an idea by the size of the pieces that I used.

Frag rack:

panmanmatt · 02-02-2008, 01:44 PM

And the frag disk:

slakker · 02-18-2008, 06:38 PM

I found some locally that are nickel plated instead of the black epoxy... it there any concerns of nickel being used in the tank? Couldn't find anything definitive re: toxicity of nickel...

panmanmatt · 02-18-2008, 06:43 PM

I'm not sure about the nickel. I would imagine that it will eventually rust in saltwater.

You get 2 part epoxy from a craft/hobby store and coat the magnets in that just to be safe.

slakker · 02-19-2008, 12:00 AM

Good call... I should've thought of that! D'oh! Thanks!

vdituri · 02-19-2008, 12:15 AM

Home Depot has some that they labeled as The strongest ceramic magnets available.
I've used them to mount xenia frags to, but will have to watch for any signs of rust or other leakage from them.

So far so good.

Ratpack · 02-20-2008, 02:27 PM

Quote:

Originally Posted by panmanmatt

You get 2 part epoxy from a craft/hobby store and coat the magnets in that just to be safe.

What two part epoxy can you get that is reef safe? I have been trying to find some, just not sure what is safe and what is not.

Thanks!

panmanmatt · 02-20-2008, 05:02 PM

Quote:

Originally Posted by Ratpack

What two part epoxy can you get that is reef safe? I have been trying to find some, just not sure what is safe and what is not.

Thanks!

Pond & Water Garden Repair Adhesive: Mr. Sticky's Underwater Glue

There is also one called Easy Cast that is reef safe once cured.

Origami2547 · 05-03-2008, 09:49 AM

Matt, I'm going to revive this thread to ask for some additional DIY info. Hope you're around to help!

First, I'm guessing that the larger magnets you've used are the epoxy-coated 3/4 x 1/8 neodymium N42 discs shown here? K&J Magnetics - Products

What's the thickness of the glass on the tank that you're showing in the pictures? (I'm trying to determine the pull strength that you're getting after separation.)

Here's a nice page that gives you some magnet calculations (such as pull strength). I've found it helpful and thought maybe other's might, too.
Calculation Tool-Kit

panmanmatt · 05-03-2008, 04:52 PM

Yes, those are the larger magnets that I amusing. In the pics above it is on a 29 gallon tank with 1/4" glass. That was just for the pics. I am currently using it on my Oceanic 70 gallon with 3/8" glass and it is holding just fine using 2 sets of magnets. I ust made one for a friend of mine for his 120 gallon with 1/2" glass and used 3 sets of magnets. I am delivering it tomorrow so once I gr some feedback on it I will post it here.

The only problem I found with these magnets is that the epoxy is very thin and brittle. It chips very easily if you let the magnets slam together. I just mixed up a small amount of 2 part epoxy and brushed a thin layer on the magnets after I assembled the racks.

Origami2547 · 05-03-2008, 10:14 PM

I'm guessing that maybe you've seen Daniel's design over at mag-racks.com? He uses black egg crate now, which is visually low-key - he used to spray paint his black with Krylon Fusion. I think he encapsulates his (uncoated neodymium) magnets in clear casting resin, also using the resin as the adhesive that bonds the magnets to the egg crate. A little research showed that one technique used to encapsulate the magnet is to drill appropriately spaced holes in a plastic cutting board and using duct tape to seal off one side of the hole. This makes "wells" that you can partially fill with the resin/hardener mix before dropping in the magnet and setting up the egg crate for bonding.

I think that your epoxy paint approach would be cheaper for small quantities since casting resin is kind of expensive.

Thanks for the answers. I've been kind of wrestling with, should I build my own magnetic frag racks, whether I should use 1/8" or 1/4" discs.

pinantanjohn · 05-17-2008, 04:28 AM

Quote:

Originally Posted by panmanmatt

I'm not sure about the nickel. I would imagine that it will eventually rust in saltwater.

You get 2 part epoxy from a craft/hobby store and coat the magnets in that just to be safe.

Stainless Steel is in part nickel, about 40 to 60 percent. There is a material that is called stellite that is 60% nickel and 40% chrome that is used in marine pumps. It doesn't corrode at all.

If the coating is pure nickel, it will be inert.

Not sure about the magnets though, I have some Ne-B/Fe (Neodymium/Boron/Ferrite) magnets that will scramble your DNA or smash your bones if you aren't careful. Ever see the ones on Mythbusters, Jamies monsters? Don't think you need that kind of power. Old speakers will have good magnets that will do the job and not contaminate the tank. Just clean all the goo off them, it's petroleum based. Old hard drives and hobby motors have good strong magnets in them too. These are just a strange shape.

Peace...
John

01-10-2008, 05:37 PM	#16 (permalink)
panmanmatt Golden Moray Join Date: Feb 2007 Location: Waretown, NJ Posts: 2,028 View Gallery Karma Komment	Re: Magnetic frag mounts Should've known you'd have tried it already. Nice growth so far. __________________ The mind is like a parachute, it only works when opened. (\__/) (='.'=) (")_(")

02-02-2008, 01:43 PM	#17 (permalink)
panmanmatt Golden Moray Join Date: Feb 2007 Location: Waretown, NJ Posts: 2,028 View Gallery Karma Komment	Re: Magnetic frag mounts OK I got the large magnets in finally. I went ahead and made up 1 frag magnet and one frag rack so far. The rack utilizes 2 sets of magnets and is capable of holding 24 frag plugs or about 12 frag disks. All my testing for weight so far has been done on a 29 gallon tank. I don't have actually numbers for the weight but you can get an idea by the size of the pieces that I used. Frag rack: __________________ The mind is like a parachute, it only works when opened. (\__/) (='.'=) (")_(")

02-02-2008, 01:44 PM	#18 (permalink)
panmanmatt Golden Moray Join Date: Feb 2007 Location: Waretown, NJ Posts: 2,028 View Gallery Karma Komment	Re: Magnetic frag mounts And the frag disk: __________________ The mind is like a parachute, it only works when opened. (\__/) (='.'=) (")_(")

02-18-2008, 06:38 PM	#19 (permalink)
slakker Cabbage Leather Join Date: Jan 2008 Posts: 378 View Gallery Karma Komment	Re: Magnetic frag mounts I found some locally that are nickel plated instead of the black epoxy... it there any concerns of nickel being used in the tank? Couldn't find anything definitive re: toxicity of nickel...

02-18-2008, 06:43 PM	#20 (permalink)
panmanmatt Golden Moray Join Date: Feb 2007 Location: Waretown, NJ Posts: 2,028 View Gallery Karma Komment	Re: Magnetic frag mounts I'm not sure about the nickel. I would imagine that it will eventually rust in saltwater. You get 2 part epoxy from a craft/hobby store and coat the magnets in that just to be safe. __________________ The mind is like a parachute, it only works when opened. (\__/) (='.'=) (")_(")

02-19-2008, 12:00 AM	#21 (permalink)
slakker Cabbage Leather Join Date: Jan 2008 Posts: 378 View Gallery Karma Komment	Re: Magnetic frag mounts Good call... I should've thought of that! D'oh! Thanks!

02-19-2008, 12:15 AM	#22 (permalink)
vdituri Excellent Guesser :D Join Date: Aug 2006 Location: Sacramento California Posts: 5,772 View Gallery Karma Komment Add yours!	Re: Magnetic frag mounts Home Depot has some that they labeled as The strongest ceramic magnets available. I've used them to mount xenia frags to, but will have to watch for any signs of rust or other leakage from them. So far so good. __________________ Victor ----- People come into our lives for a reason, a season or a lifetime. When you know which one it is, you will know what to do for that person. When someone is in your life for a REASON, it is usually to meet a need you have expressed. They have come to assist you through a difficulty, to provide you with guidance and support, to aid you physically, emotionally or spiritually. They may seem like a godsend and they are. They are there for the reason you need them to be. Then, without any wrongdoing on your part or at an inconvenient time, this person will say or do something to bring the relationship to an end. What we must realize is that our need has been met, our desire fulfilled, their work is done. The prayer you sent up has been answered and now it is time to move on.

05-03-2008, 09:49 AM	#25 (permalink)
Origami2547 Limpet Join Date: May 2008 Location: Ashburn, VA (near DC) Posts: 135 View Gallery Karma Komment	Re: Magnetic frag mounts Matt, I'm going to revive this thread to ask for some additional DIY info. Hope you're around to help! First, I'm guessing that the larger magnets you've used are the epoxy-coated 3/4 x 1/8 neodymium N42 discs shown here? K&J Magnetics - Products What's the thickness of the glass on the tank that you're showing in the pictures? (I'm trying to determine the pull strength that you're getting after separation.) Here's a nice page that gives you some magnet calculations (such as pull strength). I've found it helpful and thought maybe other's might, too. Calculation Tool-Kit

05-03-2008, 04:52 PM	#26 (permalink)
panmanmatt Golden Moray Join Date: Feb 2007 Location: Waretown, NJ Posts: 2,028 View Gallery Karma Komment	Re: Magnetic frag mounts Yes, those are the larger magnets that I amusing. In the pics above it is on a 29 gallon tank with 1/4" glass. That was just for the pics. I am currently using it on my Oceanic 70 gallon with 3/8" glass and it is holding just fine using 2 sets of magnets. I ust made one for a friend of mine for his 120 gallon with 1/2" glass and used 3 sets of magnets. I am delivering it tomorrow so once I gr some feedback on it I will post it here. The only problem I found with these magnets is that the epoxy is very thin and brittle. It chips very easily if you let the magnets slam together. I just mixed up a small amount of 2 part epoxy and brushed a thin layer on the magnets after I assembled the racks. __________________ The mind is like a parachute, it only works when opened. (\__/) (='.'=) (")_(")

05-03-2008, 10:14 PM	#27 (permalink)
Origami2547 Limpet Join Date: May 2008 Location: Ashburn, VA (near DC) Posts: 135 View Gallery Karma Komment	Re: Magnetic frag mounts I'm guessing that maybe you've seen Daniel's design over at mag-racks.com? He uses black egg crate now, which is visually low-key - he used to spray paint his black with Krylon Fusion. I think he encapsulates his (uncoated neodymium) magnets in clear casting resin, also using the resin as the adhesive that bonds the magnets to the egg crate. A little research showed that one technique used to encapsulate the magnet is to drill appropriately spaced holes in a plastic cutting board and using duct tape to seal off one side of the hole. This makes "wells" that you can partially fill with the resin/hardener mix before dropping in the magnet and setting up the egg crate for bonding. I think that your epoxy paint approach would be cheaper for small quantities since casting resin is kind of expensive. Thanks for the answers. I've been kind of wrestling with, should I build my own magnetic frag racks, whether I should use 1/8" or 1/4" discs.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)