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2 posts from April 2005

April 19, 2005

"State of the Art" - A Cautionary Tale

Imagine the position of a moldmaking company estimator faced with the most interesting of challenges; there is a project being quoted by a number of injection molding companies for a major player in the HBA market, and by the luck of the draw, no less than three shops have come to you to quote the job.

What makes it interesting is all three are in their own estimation "state of the art" operations, two independents and one a division/satellite to a conglomerate that is in a number of different businesses. All three have issued long laundry lists of declarations on how the mold must be built in order for them to have any chance of winning the bid and ultimately paying your bills.  Of course the three sets of specifications have absolutely no common ground except they are all aimed at producing the same product, which is in point of fact nothing more exciting than another variation on the theme of a "classy" cover for an aerosol can. The upside is that everyone wants to build a "good", permanent mold since the job is projected to run for several years. The downside is that the three sets of design specifications are so different that you as the estimator know immediately that there is no way for a couple of the choices to be competitive.

While all the facilities are modern with relatively new equipment, one independent runs only small presses and wants an eight cavity hot runner mold that they will try to run on a 12 second cycle, the other independent has bigger equipment and is requiring a 24 cavity tool with a planned 26 to 30 second cycle, but are adamant that only a 3 plate cold runner mold can work for this product. Meanwhile, over in Captains of Industry Land, the edict comes down that all they need are 36 toolsets to be built for one of their existing stack molds, with a projected cycle time of around 20 seconds. Happily they have also specified their price cap requirement for the toolsets based on prior buys, so you know you can meet their bid requirements and be a very happy camper.

As the moldmaker/estimator, your issues with all this are, as they say, legion. Do you follow strict procedures of impartiality, and just quote each customer exactly as per their requests? Do you tell the "Little Presses" guy that the product likely can't run at the speed he's expecting, since the wall section of the part and the material used are going to dictate an easily calculated minimum cure time pretty close to his total cycle estimate? Do you mention to the Three-Plate Mold guy that his runner scrap is going to be 50% of the shot weight, so over the years if he wins the bid he's going to have literally tons of regrind to deal with, and on a cosmetic part it's not all going to go back into the hopper? Worst of all since it's where the most money is for you as a toolmaker, do you let the toolset-only guy know that his mold expense is going to be way high compared to others you know of quoting the job, and with his high priced hourly rates on his huge Corporate Overhead machines he'll never get the price down to meet the more normal operations? Of course I know what we did in this case, being the fellow in the middle, as usual. Question is, faced with this range of options coming at you from three "state of the art" operations, all of whom have, shall we say, remarkably high self esteem and pretty positive views on "the only way this job can run successfully", what would you do?   

As we've tried to point out, "state of the art" can be pretty relative in injection molding. Being usually the outside guys called in to help fix things or just observers on the site, we see situations daily where one business or another is successful on the broad technical basis, but not making the return expected in spite of having all the newest and best hardware in place.

Here's a fairly recent example. The typical scenario, the  lucky moldmaker delivers a new mold, the injection molder tests the mold and finds performance nowhere near the projected results, and also way off from sampling results, which gets everyone into the predictable "who's at fault?" entertainment.

The job is of course behind schedule, the molder's customer is looming, and the molder's opinion is that SOMEBODY sold him a big boat anchor disguised as a mold. Again, picture a modern, clean floors, bright lights, bright young employees, well organized injecton molding facility. All the right stuff, except this new mold is making 50% scrap and running 25% slower than planned while doing it. Spend a day or two troubleshooting by phone, then of course you get to make the (hundreds of miles) trip out to try to solve the problem on-site.

Faced with a client who's facility and operation are without question in the upper class of injection houses, and who insists that every aspect of the setup and operation of this tool is perfect, how do you account for the mold running completely horribly here, when in final preshipment testing it was actually doing better than the projected/required production rates?

Back to the good old "state of the art" business again. Never assume a new facility that looks right and has all the proper looking bells and whistles on the plant floor is necessarily arranged in such a way as to operate efficiently. In this case the operation was compromised by a plant engineering decision made way back when the production floor layout was done. All machines were cooled by tower water to the heat exchangers, and all molds were cooled by chilled water from a huge central system running at a steady 40 degrees. Big water mains, big pumps, and a big mistake. Our poor mold, running a polypropylene material, needed high flow rates of 60 to 70 degree water to extract heat properly while not chilling the incoming melt so much that stresses and surface defects were introduced. With only chilled water available in this "state of the art" facility, the only way to fill the mold properly on injection was to restrict the flow of cold water to let the mold heat up, which slowed the cycle, and also affected shrinkage, so most parts were scrapped for dimensions out of spec. Incidentally someone decided to restrict incoming flow, not outgoing, so the return water mains actually vacuumed water out of the mold creating some really interesteing temperature fluctuations. Multi million dollar facility, $250,000.00 molding machines, our $50,000.00 injection mold, the people involved, the time, the engineers, etc. etc. all being victimized by  a plumber and a coin flip on which valves to close.

Happily, the law of unexpected consequences did apply here. Once we got our mold off the chiller and on its own little branch line from the tower, got everyone on board with "keep the water in the mold all the time", and got the promised production results, we had coincidentally grown for the Company a fresh crop of process technicians who were heavily into mold water flow and its impact on keeping one's job, which resulted in quite a few of their molds being re-plumbed to make life easier for the molds, the materials, and the guys who are judged by the production they get out the door.

Just another twist in the trail, out here on the Spiral Path..........

April 06, 2005

This is all Dustin Hoffman's fault!

Hi Folks, this is my first post on the Plastics.com Blog that Greg and the guys were nice enough to offer.  I'm starting out fixing the blame for 30 my years in injection molding squarely on Mr. Hoffman and that famous line in The Graduate where his character Ben Braddock is told by one of his Dad's friends: " I have just one word for you Ben.....PLASTICS!"  Somehow that stayed with me almost as strongly as the other line " Mrs. Robinson, I think you're trying to seduce me." which probably everyone else remembers much more clearly.

Long story short, and by way of introduction, that 1967 movie quote must have imprinted at the time, and took me into the injection molding business in 1970, after a minor interruption of a couple years when I was required to dress only in khaki or camo, and participate in some extended war games.  The good news is that 15 years in injection molding as a manufacturing and design engineer, and the next 15 as an independent consultant to the trade, has established that you actually can make a living in plastics. Tougher now than then, with the rise of competition from the whole wide world, but still possible.

So much for the biographical sketching, on to matters of more interest. This blog is going to be about injection molding. of course, but hopefully some shared tales of the work done, people met, and problems solved and being worked on still, will make it interesting enough for some of you to stay with me as time goes on.....

The issue of the day for injection molding, especially among the smaller shops that do custom work, is how to compete in the current market, with all the offshore competition. One of our clients has hit upon a couple of moves that seem to be working, so I thought tossing them out to everyone (with permission, of course) might be helpful.

These approaches are working well for at least one custom molder we know: Seaching for and doing custom work for local customers with smaller volume needs is one good niche, because going offshore for short run injection molding is usually not practical. Specializing in engineering resin jobs or large parts that are not stackable also limits the likelihood of losing work to the offshore producers. Working on projects where the customer himself is concerned about being "knocked off" by foreign competition seems to be the real cream, since these customers are actively avoiding the same manufacturers that are the worst competition. Oddly enough, one of the best solutions seems to be just an increased emphasis on customer service, with a downright aggressive effort to keep on every single current client with periodic calls and visits to keep them happy, even when "there are no problems".

Seems the philosophy this custom molding client is following is to maintain a visible presence with each of his customers, and to be sure no one else gets in the door. Who'd have thought that after resolving the whole laundry list of technical problems, from resin selection to product quality to packaging to on-time delivery, that my client's strongest suggestion for us all comes down to just keeping a friendly face in the customer's office (especially the buyer's) on a regular basis?

I'll be dong more of the strictly injection molding chat in future editions, since we've got a fair amount of helpful information stored up that only applies to injection. It just seemed to me that on the first step into the fray, addressing the one issue that's bothering all injection folks lately might be a better idea.

More to come later..........


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