GeneLuck_Pickerd
Plastic
- Joined
- Feb 25, 2021
- Location
- Texas
My company bought a new 4-roll CNC plate roller to replace a completely manual, non-digital 3-roll plate roller that's been in service for decades. The old manual roller was used by an experienced craftsman to gradually roll parts to the intended radius. The idea behind the purchase of the CNC machine was to flatten the learning curve for next generation of plate roll operators while benefiting from increased throughput and precision. We use our plate rollers everyday to form parts with very similar geometry, but with varying bending radii, material types and thicknesses, and parts widths. The materials themselves are not exotic: mild steel and 304/316L stainless, with M.T. ranging from 10ga to 1/4 inch. The wide variety of parts -- which are made to order per customer specifications -- means there are hundreds of parts that need to be programmed into the new CNC plate roller.
We learned pretty quickly that CNC plate rolling is different from other manufacturing processes that use CNC (like cutting or machining) because of the variables of material thickness and hardness. It's impossible to form good parts by simply loading a blank, punching in some numbers and pressing the start button without taking into consideration the inherent variability of the material. But unlike the manual plate roller, where the skilled operator rolls the material gradually to compensate for variable hardness, the CNC plate roller forms parts in one pass. If the part is overbent at the first bending moment it's already too late to avoid rework or the scrap bin. Our company doesn't do mass production, so the computer can't really "learn" the material variability by the many tweaks and adjustments a roll operator would make while rolling hundreds or thousands of the same part.
We are still rolling test pieces through trial and error to write new programs. Many of the programs we already made produce parts that require rework because the material we are rolling for a job is harder/softer than the material used to write the program. We are hoping for more consistency and repeatability by writing "hard" and "soft" version of all our programs. Yet it's already taken a really long time and literally tons of scrap material to get as far as we have -- and we still have hundreds of parts left to program.
To any plate rolling gurus out there who have dealt with CNC roll bending and programming:
We want to believe that CNC plate rolling will benefit us, but we aren't seeing any benefits yet. I would appreciate any insight you are willing to share. Thank you!
We learned pretty quickly that CNC plate rolling is different from other manufacturing processes that use CNC (like cutting or machining) because of the variables of material thickness and hardness. It's impossible to form good parts by simply loading a blank, punching in some numbers and pressing the start button without taking into consideration the inherent variability of the material. But unlike the manual plate roller, where the skilled operator rolls the material gradually to compensate for variable hardness, the CNC plate roller forms parts in one pass. If the part is overbent at the first bending moment it's already too late to avoid rework or the scrap bin. Our company doesn't do mass production, so the computer can't really "learn" the material variability by the many tweaks and adjustments a roll operator would make while rolling hundreds or thousands of the same part.
We are still rolling test pieces through trial and error to write new programs. Many of the programs we already made produce parts that require rework because the material we are rolling for a job is harder/softer than the material used to write the program. We are hoping for more consistency and repeatability by writing "hard" and "soft" version of all our programs. Yet it's already taken a really long time and literally tons of scrap material to get as far as we have -- and we still have hundreds of parts left to program.
To any plate rolling gurus out there who have dealt with CNC roll bending and programming:
How do I get this machine to crank out good parts sooner and with better consistency?
- Do you have any tips and tricks for getting better quality and repeatability despite material variability?
Do we simply need more patience and diligence and continue with the process we've been following?
We want to believe that CNC plate rolling will benefit us, but we aren't seeing any benefits yet. I would appreciate any insight you are willing to share. Thank you!