Curious if anyone has done any broaching on the MR-1 if so can you spread some light on that I’m trying to do something like this
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The spindle doesn’t lock, so our only option is rotary broaching. There are a couple of companies that make them and they do run fairly well on lower powered machines. Polygon Solutions is the company I’ve used the most and they have quite a few serration sizes to pick from.
The down side to rotary broaching is that there is no sure-fire way to know where your splines will line up. If spline orientation is not a critical feature then it may be worth a look.
All that said, I have not run one on the MR1 to attest to how it would handle the vibration, but I have run them on Tormach and Precision Matthews with success.
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Also, fyi, rotary broaching can sometimes require a massive amount of Z axis pressure.
Shallow splines with minimal material removal in aluminum is no problem for most hobby manual machines. At the other end of the spectrum, broaching a half-inch square in a piece of 1018 with even a large (10% over) pre-drilled hole takes more downward pressure than nearly any Bridgeport can deliver. I mean, auto quill feed is out of the question and manually doing it by hanging off the handle isnt typically successful either. Even in my 14x40 lathe, the part slides back in the chuck long before the square is formed most times. If you have a stop or feature to keep the part from moving and you have a two speed tailstock, the process is much more reasonable when broaching large squares and hexes in steel.
Regardless, it shouldnt be a big deal if you are doing small features in aluminum. My broach holders have 3/4 and 1” shanks, so i assume anything small enough to fit in the MR1 and have clearance would be intended for lighter pressure anyway?
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