Introduction: Forged Split Steel Cross Simply Done
YouTube has several videos on making a forged split steel cross. But, all are by people with blacksmithing experience and tools, like a gas forge and a metal cutting bandsaw. I wondered if I could do a credible job with a common MAPP gas torch and a simple hacksaw.
- Square steel stock between 1/4" and 3/8" in each side.
- Wire ring
- Angle head grinder and cutting wheel
- Angle iron
- Ball peen hammer
- Pliers or tongs
- MAPP Gas torch
- Wedges (screwdriver, cold chisel, angle iron corner)
- Flat piece of steel or an anvil
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Step 1: Pattern
There are many types of crosses. Forged split steel crosses are generally what is the common Latin cross seen just about everywhere. The arms and top piece are equal in length, although some will have a top piece a bit shorter than the arms.
I drew out a full size version of what I wanted. The steel I have is 5/16" thick. I have never found a set formula, but a Latin cross pleasing to my eyes has a bottom section about 2 times the length of each arm. (There are two lines at the end of the bottom because I decided to make it 1/16" longer than I first drew it.) As planned, my cross would be about 3" from bottom to top.
Update: After making several of these crosses, I have come to use the second graphic as a formula to plan dimensions for cutting. "A" (blue) in the graphic is the dimensions of the square stock and also the overlap of the saw cuts. "B" (red) is the length of the two arms and the top section of the cross. "C" (yellow) is the lower part of the cross and it is about two times the length of "B." The lime green area is waste to be cut away. You may still want to trim a little to make the final result more pleasing to your eye.
Step 2: Making My Own Sqare Steel
I do not have square steel bar 5/16" on a side, but I do have some 5/16" x 2" bar. I decided to cut a piece 5/16" wide from it. I clamped a piece of 3/4" angle iron to it for a guide and used an angle grinder with a cutting wheel. I needed a piece about 3" long.
Step 3: Sawing
I used my eye as a guide to saw down the length of my square stock with a common hacksaw. If I were producing these crosses in multiples, I would want a bandsaw with a metal cutting blade. The hacksaw took a little longer, but it was easier and faster than I imagined.
See the third photo. There are two hacksaw cuts: one from one end, and another from the other end, but at a right angle to the first one. The two cuts overlap by the thickness of the square stock. See the three text boxes in the third photo.
Step 4: Remove the Waste Piece
See text boxes in the photo. Remove part of one half of the square stock after making the longer cut with the hacksaw. As noted in the text boxes, I removed 1", but that was too much. 3/4" would have been about right. In the end, I cut small pieces from the bottom leg and from each arm to get the proportions I wanted and my 3" cross became a 2 1/2" cross. Such things happen when making a prototype. (See the photo in the next step for another illustration of how the square stock appears after the waste piece has been removed.) UPDATE: I have begun to wait before removing the waste piece. First, I unfold the cross. Then I can proceed on the basis of the way it actually appears instead of predicting where to cut before I can see the nearly completed cross. The results are more certain by waiting.
Step 5: Heat for Bending
My MAPP Gas torch from the hardware store did a good job of heating the steel for bending. The ideal temperature is about 1500 degrees Fahrenheit (815 degrees Celsius). The color of the metal is a bit beyond red hot and into yellow. (One piece I read on the Internet said it is possible to make these crosses without heating the steel at all, but it responds much better to working when sufficiently heated.)
In this photo you can get a better idea of how the square stock appears when the waste piece has been removed.
Step 6: Begin Splitting the Steel
A thin blade screwdriver works well for getting the splitting bend started. Bend the arms first. That would be the shorter of the two hacksaw cuts. (The steel is not hot in this photo, but is heated when bending is in process.) I mounted the screwdriver in a vise with the blade end up. Tap on the upper end with a hammer while holding the square stock with a pliers or tongs. A little wiggling with the pliers can increase the spread of the split.
Be careful. Leather gloves offer protection from burns, but make it more difficult to feel and handle fine things. I was doing fine without gloves until the screwdriver in the photo slipped when I was removing it from the vise and its shank touched my finger. I got a burn.)
Step 7: Split More
A cold chisel allowed splitting the two halves even wider. That meant taking time to remove the screwdriver from the vise and replace it with the cold chisel. I had to heat the square stock again with the torch. Again, wiggle the pliers to increase the splitting effect.
If necessary, heat again. Place the split over the corner of an anvil or a vise, or a piece of angle iron. That will further increase the split. Finally, with the arms splayed out, tap the square stock straight down on a flat steel surface. Next unfold the top piece as you did the arms. Heat again as necessary.
Step 8: Tweak
Heat the stock and tap it flat on a flat piece of steel. Chances are the arms will be cocked to one side. Heat and place in a vise as shown in the photo. Tap on the bottom end to align the arms. Be careful of tightening the jaws of the vise too much and leaving undesired marks in the cross you are making.
See the second photo. Because I removed too much waste material, the top of the cross is shorter than intended. Some crosses are made this way intentionally. I decided it is not really what I want and decided to shorten the two arms and the bottom piece by almost 1/4" each.
Step 9: Removing Saw Marks
See the first photo in the preceding step. Notice the marks from my hacksaw blade. I decided to follow someone at YouTube and distress the front of my cross with dimples from a ball peen hammer. Heat the cross again, although red hot is sufficient. Lay it on a flat piece of steel or an anvil and tap with the ball end of the hammer to cover the surface with dimples.
Step 10: Wire Loop
You can purchase wire loops that thread into place like putting keys on a key ring. I made my own with a piece of wire I bent and welded. The photo shows drilling a small hole for a wire loop. I used a fine center punch to keep the drill from skating.
Step 11: Finished
The black oxidized color came from heating the cross while working the metal. I will spray it with a matte finish clear lacquer to preserve it. You can see the wire loop I made and installed.
I read the first of these crosses was made by a Swiss blacksmith named Christoph Friedrich. Do check videos at YouTube. Some include dimensions for making different size crosses.
Overall, I am pleased with my result. I was able to make one of these using ordinary tools without the expense of a forge or the right kind of bandsaw.
1 Person Made This Project!
- The other Finnish guy made it!