Is it possible to drill and tap the rocker stud threads to upgrade them to 7/16" from 5/16" using a drill press if one is careful or is this best left to a machinist? I assume as long as the bit and tap are centred to each existing hole and perpendicular to the deck this could be possible?

 

Depends on the drill press, do you know how to align/square the spindle to the table? if the table on the DP tilts I would be careful, table should be large and sturdy enough to hold the weight of the head, a mill with a large table would be best, of course the mill spindle should be squared up to the head. Remember, a drill will always follow and existing hole, if not aligned properly will probably oversize/elongate the hole, if you have never done this sort of thing I would send it out. Where are you located?

 

Dan,
Drilling and tapping the holes is doable but keep in mind that if you are doing away with the bolt down rockers that you will have to machine the bosses for guide plates also. Not a simple as it sounds

 

Located QLD, Australia mate.

 

Yes apologies, I am only referring to shaft mount rockers, as mine are now, just with the smaller 5/16" fastener.

 

sometimes yes and sometimes no. It depends on the rocker body and the guide plate thickness. Most times I don’t machine the pads at all

 

yes if the drill press has a very large base table that won’t deflect when the end holes are being done.

a portable magnet base drill works fine too.