Magnum Venus Plastech Impregnator Roll - Manual (Page 20)

CHAPTER 7
OPERATING TECHNIQUE
The feed rates of various MVP Impregnator models vary from 5-20 feet, per minute, depending
on the model and configuration of the mold or part being laminated. Laminate thickness also is
a controlling factor in lay down rates. It has been our experience that the more mobile and
versatile the unit is, the less labor involved in actual lay down and working out of the laminate
required. For example: A bridge crane or gantry supported unit can process laminate in a given
time and with less labor than a floor mounted or cart mounted portable unit because the
laminate can be placed directly in the mold.
The mobile units have been designed with a variety of mold shapes and configurations in mind.
The controls are such that a good operator can speed-up or slow down his rate of travel to
coincide with laminate lay down rate enabling precise placement of the lamination curved
shapes and surfaces. With proper choice of reinforcement; taking drape of materials, size of
radii corners, etc., into consideration, a considerable labor savings can be gained by eliminating
secondary hand work.
The floor mounted and dolly mounted models were designed primarily for large, for surfaces or
very simple parts. Their primary function is to impregnate large quantities of FRP in the shortest
possible time, thereby saving a large amount of labor. When amounted over a carousel track or
conveyor, many parts or molds can be processed in a short time. More secondary operations
such as hand rolling, squeegeeing or use of an MVP vibrating Roll-out system may be required
because of the inability to place the laminate precisely in the mold.
The lay-down technique employed becomes very important in determining the quality of the
laminate and amount of labor involved in working the air out of the laminate. The configuration
of part will be a governing factor in deciding which technique to use.
For large flat areas or areas that have no compound curves, the best method has proven to be
to control the rate of travel and rate of laminate feed so a wave, or roll effect is developed. This
roll, or wave, will then push the majority of the air that is trapped under the laminate as it is
layed down in front of the roll. A sweep or squeegee can be employed to help work the air out
(much like applying wall paper) when using this technique.
A second method which works well with surfaces that are irregular, such as ribbed sections, is
to stretch and pull the laminate slightly. This technique should be employed anytime a vertical
and horizontal surface must be covered in the same pass. Again a sweep or squeegee or some
other tool can be employed to keep the laminate from bridging a radius.
The most common mistake a new operator will make is the entrapment of air under the laminate
as it is laid down. As a result, until the new operator develops a proven method and the skills
required to operate the Impregnator unit without first having to plan each move ahead,
secondary operations to remove air will be required; people with laminating rollers or
squeegees working air out of the laminate. As the operator becomes more familiar with the
machine and operating it becomes a reflex action, less and less secondary work will be required
because less air will be trapped under the laminate.