Typically, a shop will start out with a straight-line ripsaw and then add another as business grows.
A gang ripsaw can typically process three to four times the material that a straight-line ripsaw can process with the same labor input, plus it can deliver true parallel strips, eliminating the taper cuts often associated with single blade straight-line saws.
The straight-line ripsaw provides great versatility in choosing what parts can be ripped from a random width board, but it is labor intensive and has limited production capabilities.
When production demands outgrow the capabilities of a single straight-line ripsaw, manufacturers have two options: they can add more straight-line ripsaws, with additional labor required, or upgrade to a gang ripsaw.
On the other hand, some advantages for using a gang ripsaw include the fact that the rip width accuracy and parallelism is better than a straight-line ripsaw and can allow ripping narrower moulding blanks having less moulder allowance.
Generally, most of the cuts made on a crosscut saw in a crosscut-first rough mill are made to cut the piece of lumber into the lengths needed for the current part order, with most of the defecting accomplished on the straight-line ripsaw
. By contrast, in a rip-first rough mill most of the defecting occurs on the chop saw.
Parts recovered at the straight-line ripsaw
from a given board section will have relatively similar color and grain compared to strips that are mixed together coming out of the gang ripsaw.
However, for rough mills where multiple manually operated crosscut or straight-line ripsaws are employed, the batch processing assumption does not provide an accurate simulation.
Depending on the cutting bill, 3 crosscut saws and as many as 10 straight-line ripsaws can be assigned to cut the required parts.
Bottlenecks may occur downstream from the crosscut saw such as at the straight-line ripsaws
and the salvage saws.
Boards are ripped on the company's nine Ekstrom, Carlson straight-line ripsaws
As orders are processed, the lumber is moved into production where it is first cut to length by two chop saws, and then ripped into staves by three Diehl straight-line ripsaws
. Between these two operations, an Oliver Stratoplaner dresses one side of the stock to aid in the defecting process and ensure a uniform thickness going into the gluing process.