Similar line, had to design a gauge for our production department asap and the toolroom had to manufacture it with in 7 working days before a major visit from a OEM car manufacturer. I was given a model by the engineer in charge of the the project, spent 2 days working on the design and starting to draft up the components, including working extra hours. Only be told the model I was given was the wrong one. Modified my design and sorted out the drawing edits. Went out got the material together, passed drawings and material on to the toolroom manager. Took copies of the drawing to the lads that would be machining the parts, explaining what was what, eg what was critical, what wasn't. On one of the drawing in the material field, I had put 'Any old crap' due to the fact I had sorted some material and this gauge was a temporary measure for the visit and we could make one out the correct material once we get it ordered. All in all bust my knackers to get it done in as short a time frame as possible.
The following day I went on holiday for a week, but had notification from my manager requesting a meeting upon returning to work about the standard of my drawings. Though it would call him to see what the problem was, turned out he failed to see the funny side of my material spec and ended up having a 40min heated discussion about it all. In the end we agreed to disagree on the matter. Thought that was the end of it, but about 6 months later we had another argument about something I thought was nothing, the material comment was brought up again. At that point I realised the relationship that had been a good one, had broken down and eventually left.
Upon leaving, the company always held exit interviews, so HR could talk to you about reasons you were leaving. I didn't hold back about my disagreements with my manager and the break down of our relationship. On my last day in the morning he shock me hand and wished me well as he was going to another unit for the day. Later on I came back to my desk, to find he had placed a card on my table. opened it and it was a good luck card, thanking me for my hard work with a money voucher worth quite a lot in it. Felt pretty bad after that.