Fellows 70-15

Challenges

Converting this mechanically driven, change gear machine to a fully CNC controlled 5 axis shaping machine while rebuilding major components was a challenge. Since this machine was previously crashed, the worm gear (which is mounted on the bottom of the table) required checking for accurate tooth spacing, with no bent teeth. Also, based on the table size of 2 meters, mechanical tools available for grinding the table top surface and spacing checking were extremely limited.

Solution

MTB handled this project turnkey by dismantling, rigging and shipping the machine from the customer’s facility to MTB. The Fellows was converted from a mechanically driven, change gear machine to a fully CNC controlled 5 axis shaping machine during the course of the rebuild. The stroking mechanism was changed to allow for servo control of the elevation as well as the stroking length and speed. Rapid traverse upstroke speeds will be possible with this new configuration which will work in conjunction with the more rapid axes movements and lower setup times to reduce your overall cycle times.

 

As part of the rebuild, MTB repaired and/or replaced all seals, gaskets, ball screws, wiring (machine and cabinet), broken or bent guarding, hoses, bearings, piping, lubrication systems, coolant systems, hydraulic and/or pneumatic valves, pressure switches, float switches, proximity switches, AC motors, pumps, filters, limit switches, buttons, lamps and indicators, refinish all linear guide ways and replace all way wipers. MTB will inspect all internal gearing, shafts, castings, table, stroke guide, stroke mechanism, worktable and cutter rotation drive trains, and back off cam assembly. If any problems are discovered with these mechanical assemblies or parts, we will repair or replace them as required with the exception of the table worm and worm wheel and the cutter worm and worm wheel. I have included contingency costs for the repair of these four items should the need arise.

 

A new Siemens 840D CNC control system and electrical enclosure included all motor starters, relays, power supplies, terminal strips, etc. The existing mechanical drive system was replaced by a Siemens digital servomotors and drives of the proper torque and speed for the following machine motions: X-axis (radial feed), C axis (work table rotation), B axis (cutter rotation), Z for the stroking motion, X2 for the backoff cam assembly.