12" x 12" piece on PCNC 1100?

Looking to mill some plates where the overall size will be close to 12 x 12 with the milling slightly over 8 x 8 in the center of the parts. I see the travel on the machine is 9.5" so that is ok but wondering if I will have trouble with the part hitting the column or other parts of the mill. I looked a bit for some dimensions of the machine details but didn't find it. A local maker space has the mill but need to figure out if it's big enough. Another has a Bridgeport 2216 but it's a more complex machine to run and that space isn't as convenient.

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Originally Posted by Jim27

Looking to mill some plates where the overall size will be close to 12 x 12 with the milling slightly over 8 x 8 in the center of the parts. I see the travel on the machine is 9.5" so that is ok but wondering if I will have trouble with the part hitting the column or other parts of the mill. I looked a bit for some dimensions of the machine details but didn't find it. A local maker space has the mill but need to figure out if it's big enough. Another has a Bridgeport 2216 but it's a more complex machine to run and that space isn't as convenient.

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Spindle Centerline to Column is the number you want. It's 11" on the spec sheet (of the 1100M I think the others are the same), so the machine can theoretically do what you ask in one setup. How you do the workholding (and if things get tight, how large a cutter you can get away with) are going to be the issues and that will depend on what's on the machine and what's available.
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For work holding - Since the table is plenty long (side to side) I planned to just clamp to the table on the sides. I don't need to machine near the edges. I also don't need to run large cutters.

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Originally Posted by Jim27

For work holding - Since the table is plenty long (side to side) I planned to just clamp to the table on the sides. I don't need to machine near the edges. I also don't need to run large cutters.

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Well... large cutters actually give you a little more machinable area since you can cut up to the radius of the cutter further away from the spindle centerline, but if you don't need that, then no worries.

Of course larger cutters have the downside of reducing the maximum size if you need to machine around the outside of a piece (or machine a raised feature in the middle).

I recently had a job with a workpiece that exceeded the available X travel by several inches. I located a 123 block flush against one edge of the work, trammed it parallel to Y along the inside edge and located my X0 along that inside edge. The part had generous tolerances so may not be a good solution for tight requirements, but it give some ideas.

Probably job completed by now, but you should easily be able to machine 8x8 features in a 12x12 plate.

It's worth knowing that you can adjust the X / Y limit switches and do some editing in Path Pilot to get 18.600 x 10.125 table travel. I did this a couple years ago and have had zero issues. If you are willing to do a little more modification than just moving limit switches, more travel is available. I had to dig around this forum to find exactly what to modify on the controller - thread here https://www.cnczone.com/forums/torma...ml#post2322066

With the extended limits, I can get the spindle center to ~0.700 from the back edge of the table (and 10.125" forward from there.) Most of the X axis gain is on the right side of the table (0.500).

Also, I know they aren't cheap, but a Saunders Machine Works fixture plate opens up another world of workholding and machinability of large area parts. It's 34" x 11.950" - sits flush with the back of the table and overhangs the front by the same amount as the stainless Tormach front table cover. The width covers the entire table including coolant drain areas.