Diagnostics - The NOT so arcane science

On Different forums that I have active been with for going on 10 yrs; I have come across this issue time and again. I have had a good number of clients that primarily pay me to diagnosis issues with their machines and fix them.  What I have seen is a severe lack of some basic understanding by many folks of how to do this.

HAVE A PATTERN

The Biggest issue I see time and again is folks not having a pattern with which they check for errors. This leads to missing rather simple issues (I earned this T-shirt years ago and still keep a list of my pattern). By having a Pattern to your checks and keeping a list of them you can be sure you eliminated an issue or at least limited it's ability to be part of the problem.

Keep detailed Notes

Keeping a detailed build, maintenance, and repair log also let's you keep a much better grip on what an issue can be and track it down in a much more ordered pattern.

Learn errors (thereby learning from them)

This sounds strange but there are different types of errors/faults that are classically electrical in nature and there is also those that are structural in nature and also those that are mechanical. Learn the ground rules of each type. Document, this means you start to know the general area of where to look when an issue comes up and can shorten the amount of time finding and fixing a problem will take.

Electrical errors can be intermittent and often are. Structural errors will induce the problem at the same point each time and most often will affect motion. Mechanical errors also repeat at the same point regularly and can be mapped as such. These are but some of the primers to finding errors in each area. There are issues that cross over.

Document

Document and document. Find resources on line that cover areas you don't know and learn from them and document. By documenting what is going right (print/cutting [Feeds &Speeds] settings and results) as well as what has gone wrong (print/F&S settings and failures [lessons]) you again create a body of knowledge that you can go back to when what you think you remember does not match what is in front of you. By keeping the documentation and what happened and why you improve your product shorten time to get production done and improve your best practices. While at the same time shortening any down time and developing a list of what parts are most likely to break or have issues so that your back up stock is much more targeted instead of having a spare machine around to take parts off of.

This in turn will save back the time you took to develop the knowledge base. It is one of the main reasons machinists and CNC folks guard their personal feeds and speeds log books like pure gold and it is extremely difficult to find reference documents on feeds and speeds as they depend on the material and so many other variables (I know that there is a big push to generate these bodies of data but they are still running into the issue that variables must be dealt with and the options to do so with some ease comes at a very high price tag in sensing equipment).

So Good luck and start your log book/maintenance journal today if you have not already done so. Remember to review the logarithm to insure it is functioning and that you (we all make mistakes) did not miss a step when setting it up for your machine. A simple one follows:

Issue: Does it show obvious mechanical or electrical issues?

No-Start check list  // Yes- Go to that section and start check list

Standard check list start with power and cable checks are they all their and properly connected?

Yes good shut down so that unpowered mechanical checks can be eliminated. move on from there.

Area check list go to section and start checks that are appropriate for that section and error type. whether this is powered or not will be determined by the section of the check take proper safe guards.

That is a start point, you add in what systems need to be checked and create a sheet that you can check them off with. This saves a good bit of time in the long run and also a version can be set up for daily/weekly/ monthly/etc. maintenance.

Again good luck.