It's expensive.

I thonk I am going to change over to velcro.

Here's what I did.
Purchased Pro-Mag Dynamite magnets (50 buttons 1/2 diameter)
I found these to be the same thickness as the foam core board.

Next I purchased Balsa Dowels and 1/4 X 1 washers.

I created a 1 1/2 grid with the dowels along the masterboard and glued the washers in the boxes.

I drilled holes just big enough for the magnets to fit in the foamcore and glued them.

I then covered the "magnet masterboard" with another sheet and created a grid on that.

I foud the magnets to work fantatic!

The problem...

50 magnets - $5
30 washers $6

You figure each 1 & 2" tile gets a magnet.
Each large tile gets a magnet.

You are looking at a board no less than 10sq by 10sq.

That's 100 washers..

Then take into consideration the cost of the balsa.

It's an extra $35 or so.

Too rich for my glood...I'll stick with velcro.

I'm not sure how well it would work...but if I were going to try to do magnets, I'd pick up a big, thick pack of magnetic business cards from your local office supply store.  Pre-glued, they can be readily chopped up into whatever size pieces you desire and serve as both fronts and backs (ie, they stick to each other quite nicely).  

That might bring the price, and the work involved, down a notch or two.

Velcro isn't all that much cheaper.  I bought the large rolls and they were $18 each.  It took over 2 to cover my boards.  Granted, my boards are pretty big but theres still going to be a buy-in.  The mileage you'll get from it makes it MORE than worth it though.  
I'm glad I have my boards but making them was a tedious.  I don't want to look at squares of velcro for a long time.  ;)

I don't recall the site but you could probably find it in google.

You can buy "paper magnets sheets"  in 8 1/2 X 11, they are not to expensive and you can cut them with a pair of sisors into shape of your choice.

You can also buy "paper steel", which can also be cut with sisors, and comes in sheets of 8 1/2 by 11.  

Washers are rather thick, and expensive if your buing them at home depot or what not.  Try getting them in bulk from a real hardware store.  Probably run you 10 bucks for a box of their cheepest washers, but the box should last you forever.

Krylon (I believe) sells spray-on magnetic coating (I don't think IT'S magnetic, just meant for magnets to stick to).  Art / craft stores usually carry it.

I've never tried it, but I *think* one could use it for a project of this sort.  Basically just spray a magnetic coating onto foamcore and use small magnets on the props / masterboard pieces for attaching.  It wouldn't be magnetically gridded, but one could probably handle that by using their eyeballs.  OR, if you really want grid action, you could mask a grid on.

Along with the foamcore for my base, I also got 10 magnet tape rolls (59 cents each at the Rag Shop). I'm discovering though, that magnet tape only sticks to itself in certain ways.

It's got to do with the way the magnetic poles are positioned on this tape.

Along the length of the tape, there are two distinguishable lines of... what must constitute magnetic forms. If you stick two chips of tape together, black against black, they connect firmly enough to hold up paper models, but they "offset". Trying to lay the two sides perfectly face to face doesn't work... they just jump to an offset position again because the like poles are close.

Problem is that I can't figure where the poles are, and if I stuck the pieces on wrong, and they line up wrong on the board, then pieces just won't stick squarely.

I can't seem to figure it out intuitively right now, so I'm wondering if anybody has had a success story with using sticky-sided magnetic tape on their floor and masterboard builds. Actually, my intuition is telling me that the tape won't work reliably, but I'm hoping I'm wrong

(edit: I just noticed that two tiny strips of the magentic tape stick well to each other as it's rolled up... that is, they stick together well if both are black-side-down. I may end up gluing strips sticky-side up to the masterboard and adhering a strip on the bottom of the floor pieces.)

ya know, this is getting historical.

The ORIGINAL DungeonWorks was made by some other company. I have a set.

It was plastic walls with magnets on the bottom (like the business card magnet material) and a sheel metal "battlemat" that was 12" x 12" with a painted floor and grid.

The lesson being, quit dorking around with washers on your battlemat.

Get a hunk of sheet metal, and glue on the nice looking floors that come in the WWG sets (rubber cement, or something). Now glue a small, weak magnet, (the flexible, thin, business card type) onto the bottoms of your pieces. Use enough magnets such that the piece sits without wobbling. (4 small pieces in all 4 corners).

This should provide the "stay-put" you need. I suspect velcro would cause more stress than weak magnets would for removal. It's also very invisible.

This should solve the problem of the kid with the roll of magnets. Stick the magnets to metal, avoid the pole problem.

With the entire mat being metal, you don't have to worry about alignment. Your pieces (walls, models) will stick to wherever you need them. Some things need to align along gridlines, some inside squares. No problem.

Janx

Has anyone looked into a post-it type solution? Just a tacky surface on the bottom of the models, possibly one that could easily be replaced when it gets too gunked up...

Ideally, I guess you'd want some sort of double-sided post-it tape. Maybe a removable poster tape such as ?

Here's another cool idea:

MAGNETIC PAINT!

Just paint it on top of the foamboard before you mount the floor tiles on it. Should be *much* lighter than using sheet metal...

I've found three types of magnetic paint online (ok, so it's not actually magnetic itself, but it does have fine metal particles in it that magnets can attach to):

- sells a spray paint, but it seems it only covers 3-4 square feet per $8.95 can

- There is also a that is intended to cover much larger surfaces, and will run you closer to $1 per square foot

- Finally, there's also a company that sells a which you can mix into your paint of choice (avoiding some of the problems the other paints may have with the heavy metal particles settling out of the paint). This one will only run you $15 per quart, supposedly enough to cover 40 square feet.

Of course, I don't know how strong these are, and most recommend you apply more than one coat of paint. Then again, we may not need nearly as much magnetic strength as is needed for mounting things on a wall...

[Edit: corrected the 3rd link. I had it pointing to the wall paint company first.]

The guys selling the (note that I corrected that link...) will send you a to test things out. Can't go wrong with that.

[Edit: hmm... I wonder if those things ever get stuck in the post sorting machines! ]

[Damn, there goes my plan to paint the ceiling of my apartment with this stuff, and gluing some magnets to the soles of my boots...]

If you have any of the spray paint left over, you may want to try a more realistic test: Spray the *back* of a piece of cardstock - should work better than spraying the foamcore and then gluing the cardstock to it. In terms of getting a sufficient and even coverage, you're probably much better off painting on two or three layers than trying to do it all in one layer.

As for the other paints... If anything, I would expect the Krylon paint to be the most different from the other two, because of the different requirements that are imposed by a spray paint. Different particle size, different solvent, etc. A brush-on paint can probably get away with a much higher iron content.

Note that you can get a from one of the other manufacturers...

Thanks a bunch for testing this stuff, janx!

Sorry, stupid double post...