The rain came and so did some 'workshop time'
My 10mm plug head was nice and clean but there were one or two burrs on the joint faces that I wanted to tidy up. Neither joint face was very flat and both were a little convex as often happens when they have been cleaned up using abrasive paper. The edges tend to be a little lower than the middle. Torquing the head down well would probably straighten things out but I wanted to start with some nice flat faces.
First up for treatment was the top face. It took a few light cuts to get to a flat surface but it all cleaned up nicely within about 0.35mm.
The head was held down using two M6 studs through the outer studs near the spark plug holes.
With that done I had a nice flat surface on which to mount the head to do the bottom face.
I wanted to get rid of this gouge near one of the front stud holes, in order to give the seal an easy ride. The gouge is a little too close to the stud for my liking and while it is too deep to remove completely, getting enough surface for the seal seating is my target.
I put some clamps through the cam bearing holes and took some very light cuts across the head, paying a lot of attention to the harder steel skull. It all went quite niceley but it is always tricky skimming a big part on a small machine. Overlapping cuts have to be made and it is important to avoid any steps, just getting the tool to 'kiss' the already cut surface.
I only had to remove 0.25mm (10 thou) from the surface to get most of the gouge removed and overall everything is now nice and flat.
I may just give the surfaces a quick rub on a flat plate lined with fine abrasive paper when I have done all the other jobs.
G
