How to Make Steel Parts

Cutting steel on a lathe takes patience and knowledge of the material and its properties when cut.

Working with steel involves the use of the correct tools in order to achieve accurate dimensions in cutting. Steel often requires the machinist to use slow feeds and speeds. The speed is the RPM of the chuck on a lathe or the spindle on a milling machine and the feed is how fast you move the tool to cut the steel. Whether you are making steel parts on a lathe or mill, you must know the proper speeds and feeds to use to assure accuracy and quality in your finished product.

Things You'll Need

• Milling machine
• Lathe
• Sanding stone
• Compressed air
• Vise or fixture
• T-bolts
• Dial indicator
• Wrenches
• Tooling
• Carbide insert holder
• Center drill
• Drill bit
• Boring bar or reamer

Instructions

Mill

1. Clean the work table on the milling machine to remove any built-up debris or rust if you have not used the machine in some time. Clean the table of stuck-on debris using a fine-grit sanding stone and some oil. Remove any metal chips that have built up in the T-bolt slots using compressed air. Run your hand over the surface of the table when it is clean to feel for any bumps or areas that still have remaining debris that you must take care of for accurate machining.

2. Clamp the vise or fixture on the work table using one T-bolt on each side. Only tighten the vise or fixture enough to prevent it from moving. Place a dial indicator on the spindle and measure the vise or fixture for straightness. Move the spindle back and forth along the X axis, left to right, to determine the straightness of the vise or fixture and lightly tap to get straight. Tighten the vise or fixture down using a wrench on the T-bolts and re-check with the indicator.

3. Place the tool you will use, which can vary from a simple drill bit to an end mill and every type in-between, in the spindle of the milling machine. Adjust the RPM to a slow speed, one that is ample for steel. Most cutting will take place in the 300 to 600 rpm range for roughing and drilling; double that for finishing. Make small cuts as the steel is hard and use lubricant when available to keep the heat down and prevent damage to the tooling.

Lathe

1. Set up the lathe to accommodate the round stock steel for cutting. Match the radius of the jaws with the radius of the raw material using the proper jaws for the job. Slide the jaws into place and tighten the two bolts to keep them from sliding out. Place the raw material in the jaws and turn the chuck on to make sure that the material is spinning concentrically.

2. Set the carbide insert holder in the tool post. Tighten the two bolts on the tool post to hold the insert holder in place. Bring the tip of the tool to the outside to the raw material and reset the Z zero, which is the starting point for all left to right cuts on a lathe, for the part you are creating. Move the tool away from the material and start the chuck.

3. Set a center drill, drill bit or boring bar in the tail stock, which is centered on the chuck to the right side of the lathe, suited for drilling and boring. Start the drilling process using a center drill to prevent the drill bit from walking and breaking. Follow that operation with a drill bit and finally a boring bar or reamer, both of which are cutting tools that open holes up from their original size to a bigger size. Use slow RPM speeds on all operations.

References

• American Machine Tools: How to Use a Milling Machine
• American Machine Tools: How to Use a Lathe