It's a new year and I have some new toys to try out. The biggest one is a new milling machine (a Precision Mathews PM-932PDF) to replace my old minimill. The intent of this build log is to get to know my new milling machine by building as much of the Twin Vertical Wobbler on it as possible. I started by squaring up a piece of stock for the sub base.
Then I face milled the top.
I then attempted to tap the holes with the tap in the chuck.
On my old mini mill I did that all the time to make sure that the hole was tapped streight. The new mill with it's geared head just doesn't have the same level of sensitivity as the old mill. I ended up chickening out and finishing the holes by hand.
Next it was time to mark out and drill the holes for the pivot and crank shafts.
Then the holes were reamed to size.
My new mill has A DRO but I decided t mark out the sub base while I am learning to use it.
I used the DRO to position for the first cut and cross checked it with my laser spotter. The DRO was dead on.
I then drilled the 6-32 clearance holes
Then I picked up the outer base mounting screw marks with my laser
And then drilled them for 4-40 clearance holes.
After trying the 2 methods I think that for non critical holes the mark out and drill to the marks is faster for me.
Here is the final sub base.
Next it was time to start on the vertical piece.
Again I started up by squaring up a piece of stock
Then I faced both sides.
I then payed out and coordinate drill the tap holes for the base.
Then I set up the piece to cut the required slot. Un fortunately I got to aggressive with my DOC and I ruined the piece.
These things happen when your trying to learn a new machine. I started on a new piece and got as far as drilling the mounting holes. I decided to try something different with the tapping. I have recently won a tapping head on the bay and I thought I would give it a try. After a couple of test holes in my ruined part to set the torque I tapped the piece. On the first hole the torque wasn't high enough and I had to finish the hole by hand. On the second hole I set the torque to high and broke the tap. Thankfully the part is aluminum so it is currently bubbling away in some alum. With that I think I'll call it for this post.
Tony