Other things in life have been getting in the way of my engine building lately, that's not a real problem, but I consider my machining time very therapeutic and I look forward to it. However, I now have some time available, so I got to work on the engine.
Now that I have confirmed the centre distances for the gear train, I can proceed with finishing the timing gear cover. I have approached it a different way than that set out in the instructions, of course, the instructions have to cater for everyone and the equipment that they have, a bit of thought about the steps required and what equipment I have soon leads to a plan.
I had previously part machined the timing cover, the next step was to bore a recess in the rear where the large gear fits, and drill and ream a 1/8" location hole to be used as a reference when machining the outside rad's. I then drilled and counter bored the holes for the screws that hold it to the main block, I used the DRO on the mill to get the correct positions.
Next job was to set up the rotary table on the mill, zero the centre, then clamp the timing cover on the table, using an indicator to make sure it was centered. Then I proceeded to machine a step around the outside, although not all the way down, there will be another wider step milled later.
Once one end was done, I realigned the part for the other end, using the 1/8"dowel hole as the centre, and finished that end.
Next step was to hold the main block in the vice and drill and tap for the cover hold down screws. The timing cover was then screwed onto the block and squared up. I then mounted the block on the rotary table, making use of a steel sub plate, I drilled and tapped 4 x M8 holes to suit the hold down holes in the block. After making sure that everything was centered, I milled the outside profile that went past the cover and into the main block by .130", excess material around the outside was milled away whilst in this setup.
Now I have to do some deburring and blending in of the machining marks.
Paul.
