Helpful machining calculators

Im sure there are more out there. But Ive used both of these calculators as well as some in house developed ones at past jobs to help as a baseline starting point for different tooling. A lot of the manufacturers provide some good baseline numbers for their endmills as well.

I figure this thread can be a good compilation of different S&Fs as well as tooling combos people are using that work well on the MR1 as more of us start getting our machines running parts. One tool setup I am particularly interested in exploring is a rotary broaching setup on the MR1 for making pitman arm splines.


I only heard about rotary broaching a couple years ago. From what I understand, you don’t need CNC controls to use one. Problem is they are pricey unless you can learn how make one yourself. So is making a rotary broach using the MR-1 the plan or am I misinterpreting?

Or do you want to plunge cut individual teeth similar to this YT machinist but use a CNC program to automate all the movements instead of requiring a rotary table with the spindle rotation locked?

The idea would be more to just run a rotary broaching head in the mr1, but you do make a good point about the need for custom broaches. Ideally I would do the index style broach with a single tooth cutter, this is how I have done it in the past, if the mr1 spindle could support indexing I think this would be a really viable option, perhaps this is something @langmuirsystems will add down the line, the motor already has the encoder so id imagine its possible with some software changes.

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I really don’t know enough about it. I’d be surprised if LS could index the spindle to the accuracy required to cut splines in a 360 degree arc. Much easier to do by adding a 4th axis whether the axis be vertical or horizontal. The MR-1 spindle motor has a 1:2 pulley ratio where as a rotary table motor would typically have something like 40:1.

Cutting internal splines is very similar to cutting internal teeth of a ring gear on a planetary gear set. A skill I’ve wanted to learn for some time, both straight and helical type.

If I were to guess, I imagine you are making custom drop pitman/idler arms for trucks with high lift kits where the linkage needs a large degree of correction for the steering to operate as it did originally.

Essentially thats what we want to do yes. We have ran into it a few time just needing a custom length or drop that isn’t readily offered on the market currently so it would be really cool to bring that manufacturing in house. We also primarily work with Toyota steering boxes, and depending on the year they have a different spline count so that adds another layer to the weird parts we have to deal with.