Introduction: Poster Magnet Board

About: Inventing new and unique products for people, robots (if they ask nicely), and a few plants.

We had a need for a magnet board design that was nice to look at, easy to build, and relatively inexpensive. Specifically, we needed it for our Disc Mounts which we created to store and display our CDs around the gaming zone. Learn more on our Disc Mount Project Page. We also used it for our 3D Super Mario Papercraft Magnet Board instructable so we could build, mix, and mash up scenes from the game.

This instructable shows you how to build a magnet board using a 24 x 36 in. plastic poster frame. These frames are inexpensive, fit common poster sizes, and single tin sheet usually can be purchased in this size. You can scale the design up or down for other sizes of frames as desired.


Step 1: Get Parts and Materials

To build a poster magnet board you will need the following:

Parts and Materials


  • leather work gloves to handle tin
  • hot glue or white glue
  • tin snips (unneeded if tin is correct size)
  • tape measure (unneeded if tin is correct size)
  • straight edge (unneeded if tin is correct size)
  • marking pen (unneeded if tin is correct size)
  • hammer and block of wood (not pictured, unneeded if tin is correct size)

About The Frame: You want an acrylic face, not glass. Glass can break and is too smooth for these magnets to stick reliably. It should have a rigid backing. Hardboard or cardboard are typical. It should have tabs, staples, or a similar mechanism that bends to put pressure on the backing. The hanger should be attached to the backing, not the frame. Wood and metal frames are not necessary. We use inexpensive, plastic frames.

About The Tin Sheet: Magnets will not stick to aluminum, copper, brass, etc. The sheet can be smaller than the frame. 30 gauge sheet can usually be found at building supply stores in sections that carry heat , ventilation, and air conditioning ducting. Otherwise, suppliers of sheet metal in your industrial districts will usually cut you a piece to size. Bring your gloves to handle it.

Be aware that safety is your responsibility. Please read our Safety Warning and Disclaimer before you start.

Step 2: Remove Frame Backing

Let's get the backing off the frame. In my case, I bent all the tabs up to remove the backing from the frame. Set the backing on a work surface, hanger side down.

Step 3: Cut Tin to Size

Let's see if you need to cut the tin? Lay the tin on top of the backing and square it up (use your gloves). If it is larger than the backing then you need to cut it. If you don't need to cut it then skip to the next step. Otherwise, read on.

If I have to cut the tin, I like to make it smaller than the backing by at least 1" on a side. Smaller is fine since we are going to position and tape the tin to the backing in the next step. Let's cut it! (You are wearing gloves, right?)

(1) Prepare tin:
Lay the tin flat on a durable work surface (tin will scratch surfaces). (See picture.)

(2) Measure and Mark:
Use the tape measure and straight edge to mark lines where you need to cut. (See picture.)

(3) Cut it:
Pick up one side of the tin with one hand and start cutting with the other using the tin snips. If you are not familiar cutting with tin snips, there is a nice explanation at eHow: How to Cut With Tin Snips The cut doesn't have to be perfect, just close. (See picture.)

(4) Inspect the Cuts:
Tin snips can make sharp pointy spikes along the edges. Look at your cut. If you find any of these then use a hammer and scrap piece of wood to flatten them down. (See picture.)

Step 4: Attach Tin to Backing

We need to attach the tin to the backing to hold it in place and protect the poster from the sharp edges. Masking tape is good enough since the frame and pressure from the tabs holds everything in place. OK, gloves back on!

Place and center the tin on the backing. Use small pieces of tape to make it easy to handle and place. Note: it is handy to have your lab/shop/studio assistant hand you pieces of tape since you will be wearing gloves. Let's tape:

(1) Side one
Starting with a long side, rip off a 6-8" piece of tape and overlap it evenly on the tin and backing. Continue down the side, overlapping each piece of tape as you go. (See picture.)

(2) Make sure tin is flat
Make sure the tin does not form any ripples by putting light pressure on the tin and run your "gloved" hand across it from the side we taped. (See picture.)

(3) Side two
Tape up the opposite side just as you did with side one. Always check that the tin stays flat. (See picture.)

(4) Side three and four
Tape up the last two sides as you did with side one. Always check that the tin stays flat. (See picture.)

Note: If your tin fits perfectly into the frame (24 x 36 in. in this case) you will follow the same procedure except that your tape will overlap around the edge of the backing. (See picture.)

Step 5: Reinforce Hanger

The tin will add quite a bit more weight to the poster frame so let's take a closer look at the hanger. Flip the backing over and inspect the hanger. Strong or wimpy? Chances are it could use a little reinforcement before final assembly. This can be done easily with either hot glue or white glue.

(1) Prep Tools and Materials
Get your hot glue gun ready (or white glue).

(2) Position the hanger
If needed, bend the hanger into position. Allow enough room for a screw to slide under it.

(3) Apply Glue
Apply the glue liberally around the bracket as shown. make sure to get all sides of the hanger covered, but do not fill in the gap where the screw will go.

Let it dry thoroughly to form a strong, hard bond around the hanger.

Step 6: Reassemble Frame

Let's get that poster in there shall we. Remove the paper insert (if there was one) and the acrylic face. If this is a new frame, the acrylic may have 2 layers of protective plastic, remove them and place the acrylic back into the frame. Now place your poster into the frame. Place the backing into the frame (make sure you have the hanger positioned correctly in relation to your poster). Bend the tabs down so they apply pressure on the backing.

Step 7: Hang It Up

If you are going to hang the poster on drywall then use a molly screw (I prefer the metal ones.). This is how we hang all our poster magnet boards and have mounted up to 40 x 27 in. posters without any problems. Otherwise, put a nail or screw into a stud. Hang it, stick stuff to it with magnets, and enjoy your cool poster magnet board.

About Magnets:

Bare magnets (nothing between the magnet and the acrylic face) will scratch the acrylic over time. It is not very noticeable in my opinion. However, if you are concerned about this do one of the following:

  • Glue vinyl to the back of your magnets (usually found at fabric stores)
  • Stick vinyl inkjet stickers to the back of your magnets (usually found at office supply stores)

We use vinyl inkjet stickers with our disc mounts. Check out our Disc Mount Instructable if you are curious.