Most HMC machines include the option of retrofitting pallets and larger automatic tool changer (ATC) capacity in the field, but careful examination is required to be certain that the retrofitting option can be easily and economically implemented.

Pallet Expansion
Most standard HMCs include two pallets and the majority of machine tool manufacturers offer multiple pallet solutions (i.e. 3, 5, 8, 10, 12) that can be retrofitted in the field. However, several “expensive” challenges may be involved with this retrofit process, including:

The time necessary to perform the retrofit: It is possible that the HMC could be out of production for seven to 10 days because of sheet metal modifications and custom fitting that needs to be performed.

Software issues: Perhaps the multi-pallet software will need to be upgraded. This process may lead to additional lost production time due to software availability issues, incompatibility problems due to not obtaining the proper software revision version and loss of current programs when the software is upgraded.

ATC Expansion
Along with expanding the pallets, you will need to add tool capability to increase the machine’s milling capabilities. At the time you invest in the HMC, it is a good idea to review the ATC capacity. A standard two-pallet horizontal will come with 40 to 60 tools, which is usually not expandable in the field. An expandable system usually starts at 80 or 90 tools and can go up to 250 or 300 tools.

Efficient Retrofits
There are machine tool builders that are making the retrofit option much better and simpler to execute. Look for those that offer highly efficient retrofit solutions on their HMCs, including:

One to two-day retrofit-in-the-field for pallet expandability, from two pallets to six or eight pallets—because the machine comes fully assembled from the factory, resulting in minimal loss of production.

One to two-day ATC expandability-in-the field capability from 40 to 60 or 80 to 220 tools.
Machines designed for the retrofit capabilities from the initial concept not an afterthought.