Description of a Seaming Machine For Joining Tarpaulins

A full length poly tarp is in most cases, a number of tarpaulins seamed together. It is done to increase the dimensions of the industrial grade fabric. The material finds wide use as hay tarpaulins and also as a part of poultry supplies.

A large poly tarp is made with the help of a seaming machine. It is an advanced high speed machine with a single needle and a flat bed. The machine has a needle assembly for left shaft bushing. Other parts include the needle bearing drive, high throw, light weight bar and needle driving mechanism, filtered oil pumps for head and base, and an enclosed automatic lubrication. The standard work space of the needle bar is restricted to approximately 210 mm.

The needles of the poly tarp sewing machine are identified by a size and type number. The type number represents the variety of shank, length, groove, finish, point and other technical details. The size number is stamped on the needle shank. It represents the largest blade diameter that is measured in the middle distance between eye and the shank. The size number and type together represent the complete symbol that is given on the label of all needles.

The needle size depends upon the thread size. The thread must pass unobstructed through the needle eye for the making of a good stitch.

The poly tarp sewing machine must be lubricated at regular intervals. The lubricant should be a straight mineral oil with a Saybolt viscosity of ninety to hundred and twenty five seconds at hundred degrees Fahrenheit. The operator should fill the machine with oil before operating. The oil should reach a proper level. Be sure to check the oil level before starting the machine.

To drain the oil, remove the plug screw first. The screws are located in front, at right, below the lower crank chamber cover on the back of the machine. The lubricant must be changed every two thousand operating hours to minimize wear.

In poly tarp seaming machines, synchronization is a very important adjustment that involves the needle and looper motion relation. This is because it maintains the needle-looper relation at both the needle loop taking time as well as when the needle enters the looper triangle.

To adjust the needle bar height, turn the handwheel to position the point of looper past the needle's left side. At this time, the top of the eye of the needle should be even with the under side of the looper. To make an adjustment, loosen the screw and move the needle bar up or down as required.

The settings of the feed dog must be centered in the throat plate with equal clearance on all sides. It should end with the feed travel set to the desired stitch length. The tips of feed dog teeth should extend to the depth of one full tooth above throat plate at the highest point of travel. In poly tarp manufacturing, the tension on the needle thread should be sufficient to produce uniform stitches on the fabric under surface.