Never leave the plunger in the gooseneck (particularly when newly installed) for more than 1 hour without cycling the injection system, unless the temperature of the melt pot has been turned off, or turned down to the point where the metal solidifies. If by chance, the plunger does seize in the gooseneck, the unit will have to be rebuilt. Give us a call and return the seized unit. We can have a new or re-built plunger and gooseneck assembly to you within about 24 hours.
The flame is too hot, plus there is likely poor alignment of the nozzle tip. This allows the zinc alloy to stay on the nozzle tip, causing it to pit when it gets too hot.
Remember to always skim the dross from the top of the melt pot before installing the unit. Otherwise the dross is driven down into the injection unit, causing it to become plugged.
This is easy to prevent with a little routine maintenance. Remove the nozzle from the gooseneck once a week and coat it with a high temperature lubricant. When it does wear out, it is very easy to remove.
The limit switch is only sensing that the mechanism has moved to its full stroke, not that the nozzle seat and nozzle tip are in contact. Proper alignment procedure ensures the nozzle seat is in contact and locked onto the nozzle tip. Before trying to inject alloy, it is important to verify the nozzle alignment by performing the ’tissue test’ described in Volume 1, Issue 1 of ENGAUGE.
The shut height is not properly adjusted. As the tool rotates to shear the sprue, the tool faces are coming apart too soon. Rather than cutting the sprue cleanly, they are pulling the sprue apart. There may also be damage to sprue hold.
No! They may contain impurities. Save them up and make arrangements to return them to your zinc supplier for a credit. Let him melt them down and remove the impurities.
Not necessarily. Remove and clean the mufflers at the back of the machine. Sometimes they become so plugged with oil and dust that exhaust air cannot escape fast enough to allow the cylinders to move properly.
Many customers try to use mold lubricant mixed with some sort of thinning agent, but the Watts lubricator requires a high viscosity lubricant. All IMA systems are shipped from FisherTech with Die Slick 175 lubricant (with no thinning agent) installed. We recommend you continue to use this lubricant, or an equivalent.
You most certainly can. This requires a “raised” pot kit, a different nozzle, a new programme for your Programmable Logic Controller and a constant air supply valve. You will also have to change the length of some of the hoses. Contact your FisherTech Sales Representative to receive a quote.
You are probably using up your old stock of bushings. There is a fit dimension of 3″ +.005″/-0 (76.2 mm +0.13mm/-0) between the heads of the bushings. It may be necessary to grind the heads of both to achieve the proper fit. We have changed the specifications, and the bushings we ship today should fit without grinding.
Check the screw holding the slide assembly to the cylinder. To do this, insert a long 5/32 inch (4mm) Allen wrench through the small hole in the end of the housing and tighten the screw, if necessary. When the screw comes loose, the cylinder cannot put the slide assembly back far enough to “close” the pneumatic switch, which reverses the direction of the slide.
The ingot feeder waits about one minute from the time you pull the chain until it actually feeds the ingot. This prevents too much zinc alloy feeding into the melt pot in a short time, which can lower the alloy temperature. To speed up the process, pull the chain and depress the manual override button on the valve located inside the access port on the end of the feeder.
You’ve completed only half the job of repairing the gooseneck assembly if you just honed the sleeve. A plunger must also be fitted to the new sleeve diameter. This is what FisherTech does when reconditioning an injection unit.
In your sprue-type operation, one likely cause is contaminated zinc alloy. Have a sample of the alloy from the melt pot analysed for iron content. If iron is present, clean out the melt pot and put in new alloy.
In your “sprue” type of operation, the sprue should melt quickly and completely back into the nozzle within one to two seconds after the operating head and tool retract from the nozzle. If it takes longer to melt, the nozzle is too cold. If it is melting faster, the nozzle is too hot. A hot nozzle may cause the sprue to stick in the sprue hole and plug it.
If your IMA system has a Relay Logic Control sequence panel, the contacts in the mechanical relays could be degrading. There are several solutions: change the position of the relays on the sequence panel and see if the system will complete the cycle, or replace the old relays with new ones. Another possibility is that either the Head Closed switch failed to close during the cycle, causing it to be interrupted. Check the function of the switches.
This can relate to either a mechanical or tooling problem. To determine which it is, examine several of the sprues you pushed out. If the sprue has about 2-3mm (1/8 inches) of straight shank that appears to have been frozen and then pulled out of the nozzle, you probably have a mechanical problem in your IMA system. The assembly is not being held tight enough as it rotates to shear the sprue, or in the case of a Horizontal Cable system, the locating ring in the tooling may be worn. If you are certain the sprue is shearing properly, but the sprue still stays in the fixed tool and has a substantial tail on it, you have a tooling problem. The cavity end of the fixed tool sprue hole could be chipped or damaged, or the sprue hole could have zinc fused to the tapered surface and be in need of cleaning. In either of these cases, a visit from a FisherTech Service Technician to evaluate your system could save you frustration, time and money. If there is no tail on the sprue, it is likely a timer or a temperature problem. Check the coolant system in the tool, lower the torch flame, or increase the injection time a little to allow the zinc alloy to freeze further into the nozzle.
It is a good idea for two reasons. The zinc alloy will reach operating temperature faster, because the heating element doesn’t have to heat up the mass of ingot which solidified in the melt pot. Also, as the alloy solidifies, it shrinks, and the ingot puts strain on the ingot feeder. While the ingot feeder is a strong component, with a spring built into the hook to compensate for the strain, the few seconds it takes to lift the ingot out of the alloy will add to its longevity. It also makes it possible to remove the pot covers while the pot is still frozen.
Yes. You can operate with flash on the end of the nozzle, but the zinc alloy gets very hot and erodes the nozzle tip. It will eventually have to be replaced.