Assumes basic knowledge about creating and modifying objects in Fusion 360.
These steps will show you how to create a 25mm Threaded Bolt and a Threaded Nut that can be scaled up or down for other applications. You will be able to bolt little things together to make bigger things!
Step 1: 20mm Cylinder Shaft
Use CREATE > Cylinder to create a 20mm diameter cylinder 30mm high at the 0,0 origin point. Click on the yellow light bulb of Body1 to hide it.
Step 2: Add a Bolt Head
Use SKETCH > Polygon > Inscribed Polygon. Select the bottom plan as the face the 0,0 point as the center. Set the radius to 20mm and LMC to save the settings. Stop Sketch.
Step 3: Extrude Head
Use CREATE > Extrude to make a 5mm thick head.
Step 4: Position Bodies
Click on the grey light bulb for Body1 to show it. RMC Body1, select Move, and raise Body1 5.0mm in the Y Distance.
Step 5: Add Thread
Now select CREATE > Thread. Click ON the Modeled option. Select the cylinder's round vertical face then click OK. You should have a M20x2.5 metric thread around the cylinder.
Step 6: Assemble the Bolt
Use MODIFY > Combine to join the bodies. Select Body1 as Target Body and Body2 as Tool Bodies. Use Operation: Join and enable New Component. Click OK. In the object tree, Component1:1 and select properties. Set the Part Name to Bolt25mm. Click OK.
NOTE: This is the orientation for printing the Bolt25.
Step 7: Make the Nut Plate
Click the yellow light bulb to hide Bolt25.
Make another bolt head as in steps 2a and 2b, but make it 10.0mm high. You can use Sketch2 to do this.
NOTE: At the end of step 2b, you could have Copied Body2 and used MODIFY > Press Pull to extend the top face by 5.0mm or you could have used the Keep Tool option of the Combine process to leave a copy of Body2 to modify.
Step 8: Cut Plate
Use CREATE > Cylinder and select the top face of the Nut Plate as the reference face. Click on the TOP of the View Cube (in the upper right) to select the TOP view. Place the center point at the 0,0 position. Switch back to iso view by clicking the little house near the view cube. Drag the Height pointer down -10.0mm to cut a hole in the Nut Plate. Click OK.
Step 9: Add Thread
Now select CREATE > Thread. Click ON the Modeled option. Select the inside hole's round vertical face then click OK. You should have a M20x2.5 metric thread inside the nut plate. Click OK.
Step 10: Complete Nut
In the object tree, RMC Body3 and select Create Components from Bodies.
RMC Component2:1 and select properties. Set the Part Name to Nut25mm. Click OK.
NOTE: This is the orientation for printing the Nut25.
Step 11: Summary:
Congratulations. You now have the base components of a Bolt and Screw.
These can be scaled up or down, but 5.0mm seems about the limit for small. I've had limited success down to 5mm. At 25mm and larger, it makes a nice play toy or demonstration tool.
Use these concepts to bolt pieces of your cool stuff together!