I was able to get a few hours in this weekend, I fabricated all the parts to make the “X” axis stop blocks, this will allow me to set the length of a mortise.
I now need to measure out and secure accurate dimensions on the stop block now, to know at what locations to do the operations on.
I first use my heigth guage to reference off of the surface plate the height of the sub base, which will be the top of the stop blocks,
then I get the heigth of the bar
and with a little math determine at what heigth on the stop block I will make a witness mark to drill and ream a hole to fit the bar it rides on.
and mark the stop block piece
Now here is where making those reference flats come in handy, by me taking the stop block workpiece out of the indexing jig, I can now use the reference flats to locate it back in the orientation it originally was, however now the workpiece is turned end for end, but still able to orient the reference flats where they need to be, for additional machining.
To ensure a nice square arrangement, I use a precision square measuring block, to set the reference flat perpendicular to the table, by setting it tight against the precision block, and that precision block tight to the vise base, gives a square orientation to the workpiece, in the jig.
Now I can set the center of the spindle to the marked out line to start the drilling and reaming of the sliding fit hole.
check the sliding fit of the bar it rides on.
Now I can determine where I want to put the clamping screw
then the process of drilling and tapping to 10-32 TPI
Now here is why I chose to use my index jig for these operations, I need to now once again index the workpiece 90 deg. from its original position
so as to locate the position for drilling, and tapping the screw clamp hole.
Now I need to drill a clearance hole for the clamping screw, half the dia of the stop block,
so I measure the dia. of the screw itself
then I know what drill size would give a clearance hole
now one more thing, before I drill this hole, I need to set the depth guage on my mill machine to stop at half the dia.
now after drilling I can drop the screw in to see how it clears the hole
it is not screwed in, just sitting loose.
I made these workpiece blanks longer then needed, so now I can cut them to exact length I wanted,
again put them back into the index jig, lining up the reference flats, to be square, for the one last operation,
This last operation to this workpiece, is to cut a clearance slot,
so as the screw is tightened, the stop block ends will contract tight against the slide bar, to lock them into place.
thats all I got done this weekend, I was busy all week doing work for a client, so I had little time this week to do much on this project.
Have a great weekend guys.