Industry Technologies
by Trevor Little, Professor Emeritus, NC State University
I want to focus on High Ply Cutters that are numerically controlled (CNC) and not manual High Ply cutting machines. Since the Gerber patents expired in early 1992, there has been a constant increase in the number of High Ply cutters from around the world. Today, it is estimated that 60+ High Ply cutter manufacturers exist globally, and we will explore the benefits accruing from High Ply cutters.
Before we do, we must recognize the contributions of the Gerber Technology Company (now Lectra) in changing the entire cut and sew industry. It is also recognized that change globally can be hindered by technology being dedicated to one company for so long. While cutting blade length was standardized at 7.5 mm (or thereabouts) more recent fabric-cutting machines boast a blade length of 4+ inches (10 – 11 cm). It is easy to estimate the improvement in productivity if there is a single cutting head. However, as we move into concurrent programming, greater productivity might be achieved by adding cutting heads rather than blade length (or both).
My recommendation is for you to just hold onto your favorite thing as High Ply cutting changes before your very eyes. Today, look at Low Ply laser cutting with two laser beams on separate rails with concurrent programming that allows them to cut efficiently but at 2X (two times) the speed (Yin USA).
Accurate cutting is a requirement if automation is to be used anywhere during assembly. Automation as it exists today requires accurately cut fabric parts. One day this may not be a necessity, yet all current theories of automation require part substitution with a similar part in the American system of automation.
So, when automation is implemented across the cut and sew industry, so too will High Ply cutting will be a necessary requirement for accurately cut parts. In turn, there will be a measure of consistency from fit to style specifications and much fewer manual measurements. There are many complaints today about fit (especially) as a consumer may purchase three items, choose the one that fits best, and return the other two items. Returning items of apparel has many issues and concerns beyond the financial implications.
Another major advantage of High Ply cutting is the integration of the cutting function with other steps in the cutting room. Take for example Part ID (Identification). There are no cutters that have Part ID as a part of their cutting process. Instead, it is usually a separate beam that places Part ID on the top fabric ply only. Part ID is very important and those that can place Part ID while cutting will be ahead due to the integration of function. Another option is to have a paper copy of the electronic marker as Part ID. Electronic markers are directly delivered to the cutter, but today that is where the integration stops. Now, we are at a crossroads.
We have not yet formed the perfect solution. We have great technologies whether vacuum control, blade intelligence, multi-cutting heads, electronic markers, or papers that are porous, etc. But we forgot the manual needs. Manual needs might be increasingly important as the costs of the raw materials increase. I am referring in particular to markers that reflect the true nature of the textile fabrics.
Splice PointsLet’s begin with a discussion of the most important parameter – ‘splice points’. We all know that fabric is such an expensive and vital part of finished sewn products. We want to use as much of the material as possible which means splicing (adding) in new rolls of fabric such that all parts across the marker are included. It would also be great to estimate when the former fabric roll would run out and if all the parts were included. There are several things that should come to the forefront here: the marker maker must have knowledge of the material, the splice point must be convenient to the spreader, and splice papers need to be added so that a sewer (or operator) can extract the extra piece(s).
Another function where integration is possible is between High Ply cutting and the spreading function. The spreading function needs to know the marker length and any splice points as well as the number of plies to be spread (whether plain or rainbow). Typical installations allow the cutter to cut on several tables, therefore dislocating the cutter from the spreader.
The remainder of High Ply cutting is important such as perforated brown paper underneath, bundle papers that represent the bundle size (also porous), splice papers to alert the operators that an extra ply may be found there, and Part ID paper with printing.
Also, the cutting operation must have a trained person who understands the CNC technology of the cutter, the vacuum system, and how to bring spread fabric to the cutter.
Photo: Pathfinder Cutting Technology
An understanding of the next operations (bundling, fusing, and sewing the correct size to the correct size) gives a satisfactory cutting.
It should be noted that traditional approaches to justifying ROI (Return On Investment) based on High Ply cutting may not yield a satisfactory answer. Please remember that it is the appearance of the final product that will sell the product, not the ROI.
No discussion would be complete without discussing the typical textile industry practice of adding fabric ID to the beginning of the roll of fabric thereby wasting a lot of fabric at the beginning of the roll. Is there a better way to state fabric ID that also can match fabric inventory?
Although the Marker Maker makes an electronic marker that is at the cutter, there are manual activities that can detract from the efficiency of the spreading and cutting activities. These include marking the table as to splice points, splice papers, defect removal, and defect papers. The last thing that a quality manufacturer wants to do is have defects (or splices) in production. Having said this, some manufacturers do not remove defects and the markers do not have splice points. These manufacturers should inspect 100% before shipping to compensate for the lack of defects or splices recognition.
So, my recommendation is to proceed with caution. On one hand, there are many great cutters to choose from that cut accurately all apparel fabrics. One issue is how the cutter handles defects, splices, and part IDs. You will find many solutions as well as stories, yet we do need to find a better digital solution for the “cutting” room as we go forward. After all, spreading and cutting is an age-old repeat process of the cutting room. Let’s move ahead.
Automation in the assembly process will justify an automatic cutter. In the 1980s, automation was a common process. The industry migrated around the world but the time for automation is with us again. Automation reduces fit issues, labor costs, and standardization yet increases the need for standard parts which call for cutters that cut accurately. Most fit issues are a result of ‘shrinkage of the marker’ which can be difficult to detect without standard parts. Other fit issues include fabric dimensional change – once tumbled dry, the garment no longer fits, incorrect parts sewn together, or a change in sizing from one part of the world to the other (incorrect specifications used).
Yes, it is important to cut accurately, yet it is also important to get the correct parts together as well as to optimize the use of textile fabrics. So, to get the correct sizes an additional piece of equipment is needed; sometimes it is a traditional plotter, and sometimes it is a label maker that is part of the cutter. The Marker Maker can provide ‘splice’ points at the end of a textile fabric roll. Splicing the new roll often means going back to the ‘splice point’. This does mean an extra layer of fabric that covers the splice area.
Before High Ply cutters, a piece of paper was inserted to denote the extra ply in that area. This was known as a splice paper and was usually a different color to ‘bundle’ papers. Splicing new fabrics needs splicing information There are several ways around splicing. These are product dependent. If your company makes small items, you may be able to avoid splicing altogether as the splice area could cover many items and therefore be uneconomical. It is also possible to make short markers where the marker length determines the splice, and new fabric rolls just go to the beginning of the marker. Most of the products are larger and marker lengths are longer for gaining efficiency.
Just go to the fabric store and look at the length of remnants to learn the splice length (usually less than 1 yard) and expensive fabrics.