# Fly Cutter Choice?



## gi_984 (Mar 25, 2015)

Looking at one of the US made flycutters from MSC.  For a Series I Bridgeport (belt drive).  Debating between the straight shank and the R8 shank.  Which one (straight or R8) do you have and like?


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## pineyfolks (Mar 25, 2015)

I have both but I use the 3/4" shank one that I have the most because I have drill chucks, boring head, face mills and other tooling with the same shank. Just easier swapping between them for me.


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## gi_984 (Mar 25, 2015)

I have a boring head with a straight shank that works well.  Just concerned that a fly cutter with the R8 might be too hard on the spindle if depth of cut or max feed exceeded.


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## darkzero (Mar 25, 2015)

I prefer straight shank although I do have a fly cutter with a R8 shank. But it's a big fly cutter.


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## pineyfolks (Mar 25, 2015)

You're not going to hog material with a flycutter. If you want to take larger cuts you'll need a face mill around 2 1/2" with a 45 deg. lead angle. But most of all Bridgeport mills were not designed for heavy milling. Take it easy your machine will thank you.


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## gi_984 (Mar 25, 2015)

Hmm, never said anything about "hogging material".  Got the big Cincinnati for that.  I've debated about getting a nice face mill for the Bridgeport for a while but am leaning toward the fly cutters because of lower cost/ease of grinding the tool/less stress on the R8 spindle.  I'd rather spin a straight shaft in the collet.  Cheaper to buy a new collet if you know what I mean.


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## pineyfolks (Mar 25, 2015)

Fly cutters are the cheapest way. The cost of a good face mill is scary.  The only thing bad about spinning a tool or holder in the R8  is the key, if you have one.  I run a 3" fly cutter that probably sweeps over 4" and never had a problem.


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## gi_984 (Mar 26, 2015)

That is good to hear.  My key is in good shape.  So my goal is to keep it( and the spindle) that way. I'd have been worried someone had been overloading the machine if I saw a mill with the key broken or badly damaged.  Thanks for the replies!


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