Taking machines apart to repair them almost always results in leftover parts you cannot identify, but you still have to replace. How on earth are you going to find out if this is a bolt or a screw? Is it metric or standard? What about thread width? You cannot just order replacement fasteners without first knowing what they are and their measurements. When the pieces do not reveal any information about themselves, here is what you can do next.
Get out the Thread Gauges and Start Searching
Gather up the threaded fasteners and pull out the trusty box of thread gauges. These devices can tell you everything you need to know about these fasteners that you have to replace. They can tell you length, the measurement of the distance between thread loops, metric versus standard measurement for width, length, and thread width, and so much more. It actually should not take you too long to figure things out if you have a complete set of metric and standard thread gauges.
Write Down the Information You Gather from the Thread Gauges
Once you have narrowed all of your options down to one from the thread gauges you used, write this information down. It is a lot of specific detail that will tell the company from which you are ordering exactly what it is you need. A description of the head of the fastener helps too. No head, flat head, rounded flat head, screw head, and Philips screw head are some of the ways to describe the top of the fasteners.
Take Down the Name of the Fasteners after You Order
When you supply the fastener replacement company with the details you collected about the damaged fasteners you have, they will tell you what these fasteners are called. Write that information down, too. Store this info somewhere where you can easily reference it in the future, or where someone else working the same job can find the info and read it.
Now You Can Properly Reassemble the Machine or Equipment
Once you receive the replacement fasteners, you can reassemble the machine or the piece of equipment properly. It is a good idea to have a copy of the repair manual for this particular machine close at hand. You can reference it when it is time to insert and install the new fasteners in their expected positions. There should be no unknown parts left.