* Co sees 2011 copper output at low end of projected range

* Ramp stability issues force re-jig of Robinson mine plan

* Q3 production gains driven by Robinson mine, Sudbury ops

Oct 14 (Reuters) - Canadian miner Quadra FNX said on Friday its 2011 copper output will come in at the lower end of its prior forecast, even as its quarterly copper production rose 9 percent sequentially.

Quadra expects 2011 consolidated copper production to be at the lower end of its previously forecast range of 240 million pounds plus or minus 10 percent.

The Vancouver-based miner blamed the lower production on ramp stability issues at the Robinson mine in Nevada, which delayed access to a higher grade portion of the deposit that the company originally intended to mine in the fourth quarter.

The company cut its production forecast at Robinson for the year to 95-100 million pounds from 105-120 million pounds. Quadra said that copper production at its Sudbury operations continue to be at or above expectation.

Quadra's third-quarter copper production rose to 60 million pounds, while nickel production rose slightly to 3 million pounds.

Quadra also signed a term sheet with Xstrata Plc's nickel business to use the diversified miner's Craig mine shaft in Ontario to develop its Levack mine.

Under the terms of the deal, Quadra will pay $10 million during the first year of operation and only operate the Craig shaft and underground infrastructure. Quadra will not undertake mining from the property, the company said in a statement.

The company also noted that pricing adjustments on declining metals prices would decrease third-quarter revenue by about $6 million.