Sunday, April 14, 2019

That Sine Table Issue

That led me to ask about trig.  I may have a simpler solution. The Frankenvise base is about 5" wide by about 7" long.

1. I have some 5" x 5" red oak.  I could put that in the chop saw and make a 30 degree cut.  (The diagonal face will be sqrt(5**2 + 5**2)  = 7.07" x 5".

2. Then side mill the short end to square; put that in the vise (the long end is already close to parallel to the short end)  and square the sides by face milling and then the long end.

3. Put it in the vise and using a level, get the diagonal face level so that I can face mill it to a flat surface.

4. Then cut a slot in all four faces near the bottom of the diagonal block so the clamps that I currently for clamping Frankenvise to the table can be used to clamp the 30 degree block to the mill table.

5. Then drill and tap four 10-32 holes in the diagonal face of the block so that screw and washers firmly hold Franken vise to the 30 degree block .

Not as versatile as a sine vise, but sized to fit my mill table and use my existing Frankenvise, as well as fasteners and materials already in stock.  Then I put my acetal cube in Frankenvise and cut a right angle to get my 30 degree and 60 degree angles right angle.

Actually, the red oak is 3 x 3.  It is the basswood that is 5 x 3.  Basswood is pretty soft.  Instead of tapping it, I will make through holes, recess the bottom of the holes so the screws won't run into the mill table, and use washers and nuts on both ends of the holes to secure the screws.

No, that won't work The 5" dimension won't fit under the blade; adjusting the chop saw to cut at angle, I see a scale that goes to 45 degrees, but that is relative to the vertical.  I can't cut a 30 degree cut.

Ah, but while the block I need to mill at a 30 degree angle will not fit in the mill vise, it will go beetween the angle ears on the tilting table.  There are a couple of .365" holes that I will use to fit 5/`6" bolts through into the workpiece.  Simplest solution of all!

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