Dovetail cutter???

[sheepherder]

Originally Posted by GySgt1811

Is it possible that the difference in the angles could be on purpose so as to result in a slight interference fit to help hold the sight blade in place?

Yes it could. You would want the top of the dovetail to be slightly less than the bottom, if that was the intent. IOW, to 'lean in' a bit. I'm not very well versed in dovetail design to say whether it is a common design element or not.

If it was, I would expect that both angled cutters would be generally available for quantity production. One for the dovetail itself, and one for the part to be dovetailed in place. Is that what is common in a production workplace???

[G.T.]

Hi Rich, they may have been roughed out and broached to the final dimension?? If I was running production, that would be a real consideration for speed and efficiency?? And, I might add.. accuracy... It might explain some of the taper found in the original dovetail slots... I don't know for sure, but I would guess it could be so... best to all, til...lat'r...GT...

[sheepherder]

Originally Posted by G.T.

Hi Rich, they may have been roughed out and broached to the final dimension?

I dunno...My broaching experience has been limited to cutting keyway slots in gears, pulleys, etc. While in a production job, I've never cut a dovetail.

We did our broaching with a 24" geared arbor press, with a hand lever, .010" at a time. I never saw a dovetail cutter until I got into gunhacking. I now have some big ones, but they're for cleaning up milling machine/lathe ways. And cutting the adjustment shims for the ways.

A tapered dovetail...I don't know if that's even possible...Is it??? You would have to stop the broach at a specific point of the broach stroke, to get the same size taper each time...And have some way to push the broach back out in the opposite direction...

Beyond my experience...

[G.T.]

Yes, beyond my experience as well... but, I think a big massive broach with the dove tail cut on the length face could be used on a very fast production scale... just too much leisure time is my excuse! .........til..lat'r...GT

[Olle]

Originally Posted by G.T.

Yes, beyond my experience as well... but, I think a big massive broach with the dove tail cut on the length face could be used on a very fast production scale... just too much leisure time is my excuse! .........til..lat'r...GT

When I was experimenting with the sight leveling tool, I realized that the size of the dovetail can vary well beyond the tolerances for a press fit. I can't remember how much of a taper I put on it (3-4/1000" in 4"?), but it was still just barely enough for the barrels I tried it on.

I'm not sure how they solved this in the factories, but one or two quick strokes with an angled file would cut a taper wide enough to start the sight blade. This is what I would do for a DIY job, and it might be what they had to do in the factories as well. Unless it's the sight blade being tapered... It's kind of difficult to measure, so I don't know for sure.