Introduction: Mjolnir - Styrofoam

I saw this video on YouTube. In it, this guy makes a styrofoam gun, sticks it in a bucket of sand, pours molten aluminum over it, & ends up with an aluminum gun casting. Which got me thinking. Why not do Mjolnir that way. Solid. Aluminum. My guess is it will take about 20-22 lbs of it to cast. Then I got worried that it might be too much weight for the handle to carry. So, for the time being, I just made a styrofoam version. Or 2. ....... Ok. I made 3.

Step 1: Materials

Styrofoam (duh) ( 2 in thick sheets from Hobby Lobby &
1 1/2 in diameter rods)
Hot wire cutter ( there's numerous videos showing how to make one )
Mini Lathe ( this is important for the handle )
Wood Glue
3/4 in wood dowel rod
Sand paper ( 80 & 220 grit)
Wood ( for jigs )
Metal tape ( for smooth edges on wooden jigs )

Step 2: Research

Do your homework! Google everything!

First you need to decide which version of Mjolnir you want to replicate. I settled on the theatrical version with some compromises made that I'll elaborate on shortly. I know what version I want, now I need to know the dimensions. I googled it & came up with a couple reference photos I used. I decided that the head of the hammer looks best (for me) with a 6in x 6in x 9in dimension. The length of the handle is about 10in &
1 1/4 in in diameter. With that in mind, let's get cuttin!

Step 3: Hammer Head

Take your 2in thick sheets of foam & measure 6 in from the edge towards the center, all the way down one side. Flip it over, and do it again from the same side. I used a sharpie for my lines.

Being this was a first for me, I didn't know really how to do it. So I made up as I went along. You need to know that you're going to have to make you some jigs to get those straight edges for a clean cut. On the 1st cuts I made, I used a metal rip fence, which works great when using a hot wire cutter and cuting long straight lines. Like in this instance. But there are some tricky cuts coming up that you'll need to make a jig for, out of wood or mdf board. With that being said, let's cut.

You should have lines marked 6 in from the edge of the foam, on both sides, from the same edge, so that they line up with each other. Your measurements are crucial but not fatal. Don't stress. Take you a straight edge jig and line it up with the line on top & another straight edge jig to line up on the bottom line. Then I used clamps to hold them down. Don't clamp down too hard! You can crush the foam. But not too loose either so the jigs move around. Again, don't stress if you make indentions on the foam. It's not fatal. Yet.......

Once the jigs are in place on top & bottom, you should be ready to cut you first rectangle out. Don't worry if your jigs aren't perfect. It's not crucial just yet. But try & make it perfect. It's less trimming down the road. You'll need 3 of these rectangles. So repeat this step 2 more times before moving on.

It should be noted that you should have 3 pieces of foam, 2 in thick and at least 9 in long. My foam sheets were 12in x 24in. So after making my first cuts I had 3 pieces 2in thick and 12in long. Or did I?..........

Well they were 12in long but not exactly 2in thick like that package said! I discovered this when I glued the 3 rectangles together........

Step 4: Glueing the Hammer Head

Take your cut pieces & glue them together. As straight as possible! In one of the photos you can see a can of spray adhesive. The spray will eat the foam if applied too heavy. So don't use it! Use wood glue. I used TightBond Wood Glue from Home Depot. Plus it holds 100 times better than the spray.

I drizzled some glue on one side of one piece, then spread it evenly ove the surface with an old hotel room key. You can use whatever you like, just spread it evenly, all over. Then repeat until all 3 pieces are glued.

Clamp them together. Don't clamp it like I did in the picture though. Use pieces of wood or mdf to help clamp them together. One piece on both sides, then clamp. This way you don't get clamp marks on your hammer head.

Step 5: Cutting the Length

Once glued it should look like the picture. If you used the 12in wide sheets like I did, then you'll have a 6in x
6in x 12in rectangle. Lets cut it down to 9in long.

If you haven't noticed, when using a hot wire cutter, you get smoother edges when you cut. Once you start cutting, don't stop halfway through! You'll start to get lines that way. Take it nice & slow & let the cutter do the work. Don't force it. Steady as she goes.
Now that a freshly cut piec of foam looks better than the natural state the foam comes in, I cut off the excess foam from both ends to ensure both were smooth. So if you're going for that 9in long head, out of a 12in long piece, measure 1 1/2 in from each end. You'll be removing 3in from the length giving you 9in.

Step 6: Square It Up

We know our rectangle is 9in long. But because of my trial & errors we know that it's not 6in x 6in. It's 6in x
5 7/8. Or there about. Whatever the dimensions, it needs to be squared. After re-measuring, determine your smallest measurement. If it's 5 7/8 in, then that's as big, squared, as you can be. On one end of the rectangle, determine where the excess is by measuring. Flip it over to the other end, and mark that end, but on the same side of the rectangle you marked on the other end. Take you some long straight jigs & line them up so that you'll be removing the excess when you cut. In the photo, the colored in part is the excess. Make sur you jig lines up from one end of the head to the other end, on both sides. We're getting into final measurements now so this is important. Take your time & get them lined up perfectly. Once you feel you've done that, remove the excess with the cutter.

If all went as planned, you should now have your final shape. 5 7/8 in x 5 7/8 in x 9 in. Or in that neighborhood. The easy part is over.

Step 7: Cutting the Angles

For me, this was the most time consuming. Getting the angles right. It should be noted that if your jig ain't right, your foam won't be right. So take your time making your jigs. Measure them well! Here we go...

First I cut the long edges of the head. By looking at my research photos I determined that the angle was 45* . Make you a jig like I did in the photo. Use the metal tape on the wooden edges where the cutter will be sliding to ensure that it's smooth. Double up the tape if necessary. Remove all 4 edges this way.

Once that's done, let's cut the angles on the end of the head.

Step 8: The Angles on the End

First we need to measure. Using reference photos I determined that the end angles are about 1 1/4 in from the edge of the ends of the head. With about a 30* angle. Just get it close. You'll be happy. I was.

Make you another jig like mine in the photos. And cut all 4 sides on both ends. When that is done, the edges of the angles need to be cut. This was the hardest part for me. Building the right jig. Of course I don't have a picture of it. I'll get that on here as soon as I can. You'll just have to use your experience that you've gained so far measure measure measure. If it works out, you should have something like I do in the photos.

Step 9: Cut the Recessed Bottom

Pick out which side you want the bottom to be. Maybe a side that might have a knick or indention in it.
The first measurements are lines 1in from the ends of the flat part. Never mind the big X in the photo. You want the marked box cut out. Once the lines are marked 1in from the edge of the flat surface, connect the lines down the side so that you have a box. This is just for visual reference.
Now determine how deep you want to go. I went with 1/8 of an inch. Using jigs on bith sides, cut down on one line & drag the cutter across the box you just marked, to be cut out. I found it easiest to drag the cutter towards you. But don't go all the way. Start your cut and go about half way. Flip the head aroud & do the other half. That way when you plunge the wire cutter down, you get crisp edges, before dragging the cutter across. I used a dremel on the little slits coming down the sides. I just eyeballed them. So be careful.

Step 10: Can You Handle It?

Your head should be ready for it's handle. Here's where the mini lathe comes in. If you don't have one, I wouldn't know how to get it to like it does without it.

So this was another trial & error for me. My first attempt was annoying. My lathe can only handle 12in lengths. Which is fine for this. I started with a 10in piece of a styrofoam rod. With a piece of wood on both ends. The foam is just too soft & flimsy for this kind of approach. So I started cutting the rod into sections to be glued together later. Putting a section at a time on the lathes & turning it. That didn't go well either because the length of the sections would vary & it just didn't look right. And it was time consuming. So I decided I would put a wooden dowel down the center of the handle for increased strength & durablity. Best decision I made on this project.
Cut out sections about 1 1/2 inches in length. Bore the center out with a 3/4 in bit. Insert the 3/4 in wooden dowel in the bored out pieces and glue them. Glue the dowel and in between each piece. When dried, put it on the lathe and turn it with sand paper. Use the 80 grit to remove alot quickly and the 220 grit to smooth it out. I made a jig with slits cut every 1inch. Then I glued sand paper to the jig and used that for the final shaping of my handle.

Step 11: Now What

That's as far as I got. I'm gonna add some latex paint to it so I can go back and add something on the outside to help smooth it out. Maybe bondo. Not sure if that would get too hot for the foam. The latex will be just for protection. Anyways enjoy. Good luck.