And I had a saw arbor.
With a couple custom-sized washers, it accommodates all the various sizes of saw blades on hand.
OK, here's the base on the TF79.
Removed the two M4 screws.
It's about 18mm wide. Did some layout on the aluminum leaving a bit of extra width to play with.
Quite a bit taller.
With the workpiece on parallels, it took a few passes to make the cut.
Note that this is not a proper endmill for aluminum. The aluminum really wants to weld to the cutting edges ruining the finish. But keeping it lubed and brushing it off after each pass left a beautiful finish.
Cleaned up the ends.
Marked center line.
The gas tube on the TF79 was roughly 19mm. Close enough to use a 0.750" ball mill to cut the profile.
Not quite centered as you can see by the edge thickness on the left compared to the right. Not shown: Milled the right side down until it matched.
Measured the thickness of the stock base and added 0.185"
Milled away the excess.
The original base has 60 degree dovetails with the top of the base measuring 11.5mm.
By only cutting on one side and flipping the workpiece in the vise for each successive cut, the dovetail remains in the center of the work. Advance the cutter, make the cut, flip the workpiece, make the cut.
I stopped when the top of the dovetail measured 11.5mm.
The mounting holes are exactly 80mm apart on the gun. Spotting drill to locate the hole,
drilled for clearance,
Test fit with new, longer, mounting screws. Each countersink is finished when the head is completely flush with the surface.
Deburred the edges and it's done. OK, maybe not done. I'll put a satin finish on it later so it matches the other aluminum parts on the gun.
Not too bad. Missed my self-imposed height goal by 0.001". The base mates perfectly to both the gun and the sight. Dialed the sight to the middle of the range and in 5 shots it was good to go.
Thanks for reading. Check back for more soon.