Hi to all,
since long I have considered how one could cut a gear rack on a Deckel (my FP2 in particular). Currently, we (along with my friend Kyriakos) have started repairing two HLVHs, the rack being one of the things that need to be replaced.
We got a competitive quote from a gear cutter guy, so we'll outsource the part. However, for the sake of completeness, I still would like to have a way to do this on the FP2.
The thing is that, I can't find a sane way to set the work up. The optimal approach would be to use a rack cutting attachment, like this Brown-Sharpe item shown here:
![Click image for larger version.
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This thing has a very low profile casting so that the spindle ends up very close to the table, enough to be able to fit a gear cutter that could clear the head and actually be able to cut.
On the FP2, this is not easily accomplished. Regular vertical head is fat enough, fatter than the cutter. The angular spindle head fits perfectly in terms of dimensions, however I don't think it should be assigned such a task, due to the sensitive MT1 spindle. Doesn't feel right to put a gear cutter on a MT1 arbor and cut a rack on steel, but I might be wrong.
Horizontal spindle is not an option for anything but very short racks.
Working along Z also doesn't provide any gains, still the clearance issues with the vertical head.
If I HAD to run such a job, I would prepare a fly-cutter type tool that would clear the OD of the vertical spindle (cut a tooth off a gear cutter and braze it onto a shank, and fit it on a fly cutter). Then flip the vertical head 90 deg and work exactly like in the Brown-Sharpe image. I would not feel very comfortable running this cutter and, I guess, it would also wear out rapidly (since there is one cutting edge only), but if the arbor is short it might work. Can't think of anything else though...
(indexing is another story, actually I had thought about indexing the new part off a fixture that would employ a small, unworn, portion of the original rack to be copied. Would not rely on the DRO, but, as I said, this is another discussion).
Would really like to see how the forum has done (or has considered doing) such an operation, I might be missing something.
BR,
Thanos
CM - Series - SPINNER Werkzeugmaschinen
