The valve levers are a one piece construction using 8MM hex brass. Indicated the dividing head on the mill and drilled the two 2mm holes spaced at 15.55mm.

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As can be seen I rigged up a simple jack to support the material for drilling and milling. Next, milled it to a thickness of 2.4mm.

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Off to the lathe, where I centre drilled the brass so that it can be supported by a live centre for the lathe operation. The centre portion was turned to 1.67mm.

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I only need four but made five just in case.

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My dividing head came with a chuck and backplate which was screwed into the nose of the head. It had a Myford thread, so at that time I had also got an 2MT adaptor for the chuck with the idea of using the chuck on the rotary table. I had never used the adaptor before. Indicated the rotary table with the adaptor in it.

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Screwed in the chuck and clamped a piece of 5mm BMS in it. Drilled and tapped for 2mm and bolted on one of the unfinished rods.

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Started rounding off the ends of the rod. It worked. In no time I finished all the rods.  It took more time to do the setup.

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Next came the valve bonnets. I made four blanks from a piece of 16mm brass.  Here I am milling the four of them together to get the proper height.

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I then drilled the four 2mm mounting holes in each blank. I could have drilled and reamed the centre 3mm hole also but I thought it would be better to mark it at a later stage.

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To finish the valve bonnets I first made a temporary prick punch from a length of 6mm stainless steel.

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I also marked each valve, valve hole and valve bonnet so that each one always goes in the same place. Fixed the valve bonnets in place and using the prick punch, marked for the 3mm holes to be drilled and reamed.

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At the end I ended up opening up the reamed 3mm hole with a 3.1mm drill for a better fit.

Next, a simple fixture was made to machine the front part of the bonnet.  Clamped a piece of aluminium in the lathe and faced it off. Drilled and tapped for 3mm. Used also a 10mm diameter aluminium washer I had also previously made.

All four valve bonnets finished and some gaskets made for them.

Drawings here

Part 20 here  Part 22 here