I've seen it mentioned before. Options are to use a ball nose cutter along the grooves, plunge with a milling cutter to increase the covers PCD or turn a waist on the studs so the unthreaded part is a smaller dia
Stuart Twin Oscillator build
- Thread starter Sarah
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Thank you for your response Jason 
I took the first option. I took some measurements of the cylinders and covers, made a CAD drawing which indicated a 0.3mm cut into the cylinder grooves. I actually took a 0.4mm cut with a 2.5mm ball end cutter. I tried the covers over the cylinders and they fit nicely.
Thanks again for your help Jason.
I took the first option. I took some measurements of the cylinders and covers, made a CAD drawing which indicated a 0.3mm cut into the cylinder grooves. I actually took a 0.4mm cut with a 2.5mm ball end cutter. I tried the covers over the cylinders and they fit nicely.
Thanks again for your help Jason.
According to the plan for the Twin Oscillator you take a chunk of mild steel and turn it down to a 1/8" disk with a 5/32" shaft coming off it. I didn't really like that approach, so I fabricated it from a seperate disc and shaft, then added the small offset shaft.
A little more progress in our buddy build. The Twin Oscillator has been assembled, though quite a bit of fettling was required to get the parts to fit. With shafts and holes made to plan, a bit of polishing was required to get them to fit. It turns over but is quite stiff, the pistons seem a tight fit in the bores.
