Gum Pot Instructions

GUM POT: Three different types of gum rolls are available to suit the varying conditions found when operating the machine. Each user should determine which type fits his requirements the best. When using hot gum the standard roll for a full wrap label is a series of metal gears such as shown on Instruction Sheet 5 and 6. On machines applying spot labels, using hot or cold gum, a solid rubber roll is used in order that gum may be applied to the container along its full width. See Instruction Sheet 7. The third type is similar to the first except that narrow rubber tracks are used in place of the gears and as many of them can be used as desired. This is illustrated on the Instruction Sheet 8.

The adjustable rocker arm mounting of gum wheels permits a more positive application of gum especially when cans are dented. When cans roll over gum wheels this rocker arm should move down approximately 1-32”. The 1/32” movement can be maintained by adjusting the knurled screw located on gum pot and resting against the arm. Always be sure to tighten thumb screw after making adjustment. See Instruction Sheet 5.

When adjusting machine be sure that gum rolls are free on the stationary shaft on which they run since the two outside gum wheels have flanges which run in grooves on the underside of the can tracks, and therefore, move with them. It is a good idea, if the adjustment is seldom made, to remove the shaft and the rolls before adjusting and replace afterwards. This will eliminate all possible springing or breakage.

Always see that the scraper on the bottom feed roll is set close to ends of the teeth. If this is not adjusted correctly, it will feed too much gum to the top roll, causing it to collect on the edges of the roll, then on the can tracks, then on the cans, and finally on the carrier belts – causing the belts to tear the labels off the cans which have been correctly labeled.

Adjust the top scraper close enough to the roll to allow a very thin smear of gum to be deposited on the can. The operator must bear in mind that too much gum is just as bad as not enough, and he must determine the proper amount.

When using cold gum, it is not necessary to wash the pot every night, providing the machine is going to be used the next day. (But it is necessary to remove the top gum rolls, and put them in water.) The operator should plan to have as small an amount of gum remaining in the pot at the end of the day as possible – so that fresh gum can be added before starting the next day’s run. This fresh gum will moisten the gum that remained in the pot, causing it to work satisfactorily.

When using hot gum it is not necessary to remove the pot since the gum will solidify as it cools, nor will the gum spoil no matter how long it sets in the pot. It is important, however, when starting the machine that the hot gum is in a fluid state as mentioned elsewhere in these instructions. Be sure to turn the gum pot drive shaft by hand before the machine is started up. If the gum is not allowed to become liquid before starting the machine the gum rolls will not turn and the gum pot drive will be badly damaged.

To remove the complete pot for general cleaning, remove the two clamp screws and pull the pot toward the operator. Remove the top gum rolls and all brass scraper plates and put everything into a container of water overnight. When putting the pot together be sure that all oil holes are free of water and filled with oil. When placing pot on base the driving gears at back of pot must be properly meshed before tightening the clamp screws. Also see that the stud on the bottom of the pot enters into slot of bottom base properly.

Under normal shop conditions a thorough inspection and test is made of all machines and they label perfectly before shipment is made. The purchaser’s warehouse and container conditions may differ from the conditions under which tests were made. Therefore, the operator will have to determine by experimentation which type of gum, which speed, and what temperature will give him the most efficient operation of his machine under his local conditions. Some of the difficulties which will arise in packing plants or paint plants are due to temperature variation in the containers or condition of the surface of the container (such as wetness or oiliness). Gum can be purchased to overcome any of the difficulties, but it is almost impossible to label containers when one is hot and the one immediately following wet or greasy. Therefore, it is important that the packer maintain uniformity of conditions. It can readily be seen that it is impossible for the manufacturer to know the customer’s warehouse and container conditions.

When using cold gum, rubber gum rolls should be used. If the metal gears are used the teeth may be broken because of the fact that cold gum works very much harder than hot gum. The gum pot switch in the starting box must be turned off when running cold gum unless the operator desires a little heat, in which case the switch should be turned low.

When using hot gum always run the gum hot enough that it won’t string. The strings, of course, get all over the machine and in time make it impossible to apply the labels neatly. Some gums, however, will string a little bit without causing much damage. Hot gum permits greater flexibility because its stickiness can be changed by the thermostatic controls to meet varying conditions in the warehouse. Furthermore, grease or scum which may collect on the cans has no effect on hot gum. If the gum is too hot the cans will pass over the label partly picked up, but again drop it and pass through the machine unlabeled. The reason that the label is dropped is because the gum is not sticky enough to hold the label after it picks it up. A lowering of the temperature of the gum will help. If the gum is not hot enough it will not be sticky enough and the labels will again not be picked up. If must be emphasized that the temperature of the gum is dependent on the temperature of the can since hot cans would require a colder gum that cold cans. A further trouble will result when gum is run too cold because of the fact that the top gum wheels will carry an over supply of gum on their sides. The gum, in turn, will flow out on the can tracks and from thence onto the can. The gum will also leave a large blotch on the body of the can causing a rough lap of the label.

Besides varying the temperature of the gum it is possible to meet varying conditions by changing the speed of the machine. Machines have three speed step pulleys. It is suggested that the different speeds are tried for varying conditions especially with hot gum. For example, if the cans miss picking up the labels and cold cans are being run at slow or medium speed the gum probably has set or hardened before the cans roll onto the label to pick them up. By increasing the speed of the machine it will cut the interval of time between picking up the gum and picking up the label. The shorter interval of time may not allow the gum to harden, thus allowing the labels to be picked up.