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To engrave legible numbers in tooling, grasp the grinder (they come in all sizes) with both hands (top) to get better control vs. holding it like a pencil (below). Using a ball stone vs. a ball carbide cutter also lessens the chance of “grabbing” and helps keep the engraving neat and legible.
This shows an array of different hammer sizes (weights), types of steel, and lengths and types of handles used in mold repair. They all have their place during specific stages of mold repair. Knowing which one to use in what situation, and then controlling it, depends upon both soft and hard skills.
Above are examples of popular “store bought” hammers that are in many tool chests around the world. These hammers have a hardness of around 55-58 R/C and are destructive to mold plates and tooling, especially if a hard “miss hit” occurs.
A better choice for hammers is to make your own hammer from cold rolled steel (20 RC) and an oval-shaped wood handle for better control. Size and weight is dictated by the size tooling worked on
These hammers are brass, copper, and aluminum, which “flake” during use. They should only be used during disassembly.
The simple act of holding a micrometer steady can be difficult for some. Hold it the wrong way (above; the way the majority of trainees try to do it) and two things can happen: The base will lift slightly when the spindle is run down giving you a false reading, or the micrometer can “shoot” out from under your fingers if pushing too hard and ruin this expensive tool.
The four, two-man maintenance teams were ready; and with molds assigned and the safety speech delivered, they officially began their mold-repair assignment. The experienced mold-repair technicians on Team 1 grabbed their pry bars, placed them into the pry slots of the mold and began yanking like they were pulling nails from an oak plank.
With a foggy feel and half-blind to visual clues to what the plates—and each other—were doing, this procedure instantly cocked and jammed the plates and tooling together. On a different mold this pry bar “technique” could have been deadly.
Later, at another bench, Team 2 could not figure out why, after removing all of the bolts, the cavity blocks in their mold still would not come out. When swinging a 2-lb rawhide hammer through several solid whacks didn’t work, it was deduced that a 5-lb hammer was needed as the blocks seemed just to be “stuck.” It would have been prudent at this point to stop and look for the reason the blocks were being stubborn. But like bell ringers at a carnival, the hammer came down with a vengeance—and a hope—that the blocks would come out and indeed they did, effectively cutting the two copper water lines holding them right in half.
Just a bit more patience, closer observation, or a quick glance at the maintenance manual would have revealed that the cavity blocks can’t be removed until you take the water lines out first. So it was apparent after this that both teams would require specific hand-tool training to do the more tedious, exacting work that was scheduled for the remainder of the week-long course. But then that’s why they were here.
LEARNING BY DOING
Hand skills can’t be taught in a hotel conference room, during an online maintenance course, or in any kind of “virtual” training scenario. Technicians need to be shown the correct way to hold the correct tool, how the work needs to be held, and how it needs to be positioned in relation to the body and the type of work being performed. Then the whole process should be practiced repeatedly to train the brain to move the appropriate muscles precisely and confidently.
The physical side of using (controlling) tools is only half the story. Years ago in the Navy, a senior jet mechanic used to regularly critique the bench techniques of rookie mechanics. From the way we stood or the stance we took when moving or working on jet engine components at a bench, to how we used hand tools, every move was dissected, discussed, and lessons were learned…or more accurately, “drilled” into us.
Our most skilled and respected mechanic preached that every tool we use requires the ability to innately measure, and in most cases overcome, different types of resistance such as installing, loosening, tightening, removing, repositioning, cutting, bending, and even using precision measuring tools. Doing this safely and effectively means paying attention to details that often escape those who view using tools for a living as brain-dead work.
CAN YOU FEEL IT?
Usually, the connection from the head to the hands gets shorted out by a lack of patience, maturity, or an inability to focus on multiple limbs at the same time, all of which result in a difficulty with accurately reading work resistance and controlling the force of the tools we use.
There is a misconception that everyone is born with the physical skills necessary to effectively handle wrenches, hammers, drills, and all the many tools that are required to perform work on something—in our case—a mold. It’s believed that it’s just a matter of choosing to use our hands instead of our minds, because anybody can do it; and that what really sets a good repair technician apart is his or her knowledge of how molds are built or his/her ability at a lathe, grinder, or piece of CNC equipment.
But the numbers say differently. After working beside hundreds of repair technicians and toolmakers with varying experience levels from companies all over the globe here at our training center, there is no doubt that a stake could be hammered through the heart of the opinion that anyone can turn a wrench. It takes both hard (physical) and soft (gray matter) skills for any tradesman or repair technician to be considered a craftsman or journeyman, the pinnacle of this field. Being good at only one won’t yield favorable results for man, mold, or company.
It’s the same for an athlete. Take, for example, a quarterback. Just because he knows the game and has the brains to read defenses doesn’t mean he has the skill to throw the ball exactly where he wants it. Conversely, let’s say he can put the ball on a dime—it can’t be assumed that he can read defenses and “feel” the pressure by judging the distance, speed, and angle of opposing players. For him, as with skilled tradesmen, it takes a blend of brains and muscle control to excel at his chosen position.
The ability to discern through “feel” when an Allen wrench is stripping (stripping means that metal is being displaced) or twisting (steel bending) can dictate the end result, and potentially additional labor hours, of trying to remove a stuck bolt. Other job-related examples that require a “tuned” sense of feel (and there are hundreds of them) include when a small, ¼-20 tap is about to break; a bushing or tooling component is too loose or tight; a 0.001-in. variation of tooling component heights; or even when the pores of a small hand stone become clogged/loaded while polishing.
The simple act of swinging a hammer repeatedly without hitting yourself or damaging the surrounding area is a perfect example of dexterity that may sound modest, but unless you have clear connectivity from the head (to judge the resistance) and muscle coordination (to control the swing), the hammer may not go where you want it to, nor will it make contact with the right amount of force.
TIME TO TRAIN
So how do we get better at hand skills? Some unfortunately can’t, and would probably be better off looking for a different line of work. For the rest, getting better at hand skills means breaking down a specific motion by knowing the correct areas in which to focus attention. It’s about ergonomics and giving oneself the best opportunity to control this motion. It’s about muscle repetition and the brain’s ability to know where your limbs are and what they are doing without looking directly at them.
It’s about understanding leverage—like cheater bars and extensions, and how much force is needed, how it is applied, and the effects when using these tools. And then it’s about using good tools that precisely transfer the resistance encountered to your hands, and about the different sounds when using them. It’s about the discipline required to use tools designed for a specific job versus the tool that is lying close by. A pry bar can be used as a hammer but it is not designed or built to swing at or strike something.
On the matter of hammers, in our jobs as repair technicians we are constantly dealing with installing and removing close-fitting and “tight” tooling components. They are termed “tight” because of the corrosion or lack of lubrication between components, or just plain old tight tolerances. The simple hammer is probably one of the most used—and overlooked—tools in a repair tech’s arsenal. The improper use of this tool is responsible for more damage to molds and components than any other tool we use.
There are several myths about hammers. The most prevalent would be that soft steels such as brass, copper, and aluminum won’t harm hardened tool steel. Not only will they easily round over, ding, and damage hardened tool steel, but they “flake” easily when used and leave small chips behind that fall in between plates and components, causing O-rings to leak, tooling to not seat properly, wiring to short out, and galling in dynamic (moving) tooling. Soft, cold-rolled steel is a much better choice for hammer material.
Another popular myth concerns the purported benefits of using “dead-blow” or shot-filled polymer hammers on molds. They do exactly what they advertise, but that doesn’t mean it’s the best option in our trade. Why not? The user feels no rebound force, nor does he or she hear the “ringing” sound that warns of a super tight fit. Using a hammer during assembly that is designed to absorb force robs the user of the ability to feel how much force is being applied and to accurately judge tooling movement. So we must rely on sight to tell us if the tooling is entering straight or not. A slight misalignment or a few thousandths of “cocking” the tooling can cause considerable damage if not recognized quickly, so reading the fit is extremely important here.
THE DEVIL'S IN THE DETAILS
To many, particularly those who do not work with hand tools on a daily basis, the above details will probably sound like overkill. But to the manager of a tool room, repair technicians, or anyone who is responsible or affected by mold downtime, the level of detail that we practice every day will dictate just how safe, efficient, and accurate our repairs are.
It can be difficult to put a cost on the issues caused by a lack of hand skills, especially if there is too much inconsistency among repair techs with regard to the tools used while performing specific, critical jobs. We can and should create maintenance manuals for all of our molds that describe bench techniques in detail to ensure the best chance of success.
The connectivity between the head and hands stands a much better chance of improving when we know, up front, specific criteria about the jobs we do and the procedures we use when working through the different stages of repair. Armed with this knowledge, it then is up to the technician to practice controlling tools while paying strict attention to the “resistance feedback” that quality tools connected with a keen sense of feel will provide.