Day 197 of Machining the grove in the first eccentric strap.

(Day 197) - Machining the grove in the first eccentric strap.

Hello! I say day 197, almost feels like it. I've been on this for weeks because, for my piece of mind, a high degree of accuracy is required for this fit. I'm prepared to allow it to wear in (a bit) as I have been machining it by 0.1mm at a time, and have removed and test fitted it many time. 

The photo (right) is almost there, but not quite, and some scraping with a HSS tool in the corners has been done to achieve a dead square corner. 

Finally!!,  Last night it fitted and revolved smooth, however after the application of some 3-in-1 Oil It did go a little tighter. I can only imagine the oil was sealing the parts together, as they are a really close fit, but after some more scraping in, and using a blue marker pen, to see the wear marks show its finally complete.   

  

It just remains to complete another 2 to the same standard, and hopefully it should be quicker this time.

The main problem was the inability to measure the inside depth of the grove, as none of my measuring tools would fit inside so I had to rely on the alignment jig to keep the datum when removed for disassembly and measuring. An internal bore gauge can be used but it needed to be split to get the gauge out to measure it each time with a vernier. I have now made a curved insert to drop into the slot for a quick reference, like a steel Joe Block but curved to match the internal profile.   

                            Until Next month, stay safe, make swarf and be the best you can be.