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Tips for the JIT Gear Manufacturer and Job Shop
If your shop already repairs or manufactures gearing components, you may be interested in this article. There are some
options you have today that shops 5-10 years ago didn't have. And it doesn't all revolve around CNC. So let's
peel back the lid on small to medium gear shops everywhere and examine some new-age problems and solutions.
For nearly a century gear hobbers, shapers, bevel generators, and thread mills have been serving industry well. CNC gear equipment is rapidly replacing manual counterparts where large (1M+) capital investments make good sense. If you are "Fortune 500" enough to commit to large debt then wild horses aren't going to stop you. But you should pause to consider this question: Will CNC be a necessity or a convenience?
You guessed it. The substance of this article deals with shops that are looking for cost effective alternatives to CNC. Especially where very large equipment is doing very large work, and the cost of a CNC replacement would be VERY large!
You probably know shops that have given up on gear cutting, suspecting that global competition was the reason. Surely a shrinking world has made off-shore manufacturing economical to major consumers of gear components. Most small to medium-sized gear shops have typically served "Niche" markets where the trump card is fast turnaround. Small shops have done well without breaking into markets dominated by the "big boys". So what are the real reasons for any small gear shop to be worried? No one has all the answers, but two factors seem universally true these days:
(1) Qualified employees with manual machine experience are becomming rare, and
(2) Just In Time (JIT) ordering is turning profitable production time into costly changeover time.
This is nothing new to the established gear shop that probably enjoys the lowest overhead possible. But any small shop owner recognizes serious obstacles to sustaining and growing the business. For instance:
Is one person doing setups and changeovers? Let's call this person "Gear Man". In a small shop, Gear Man is probably helping with quoting and special tooling as well. What would happen to your operation if Gear Man were no longer available?
Is most of what Gear Man does "in his head"? Does he spend over an hour calculating the next machine setup?
Do new prints and engineering changes obsolete the "good-as-gold" setup you used last time you ran the "same" job?
Do jobs stall all too often, waiting for a correction to a simple mistake in the calculations?
Are approximations in your setup calculations causing some first-piece inspection rejections?
Are you rejecting jobs from good customers because it requires a new machine, new skills, and a new Gear Man? This can discourage shops that are doing hobbing work from doing bevel gears. Shops that do spur bevels may never try to take on spiral bevels.
If you had to honestly answer "Yes" to most of the questions above, then think about a tool that makes gear machine setup so simple that you could easily explain its use to a novice. You would want to use it during quoting so that there would not be surprises later when setting up the machine. It would have to be fast and accurate, and get the first piece right without mistakes.
If you think this is all to suggest that CNC gear cutting is the answer, guess again. The tool here is your shop's PC running the right software.
This is not a new idea. Before commercial software was available, a number of shops saw the need for in-house software to do their setups and summaries. Knowing what is involved with developing programs like this, I assure you that these shops went to great trouble and expense. And just as surely they guard their software from competitors. After all, anyone can buy the machines and tool up for the work, but few have the "PC advantage" these shops have.
But all that changed about 10 years ago. Now anyone can buy software professionally developed and tested to create setups and summaries. This software is available for all gear hobbers, thread mills, and some popular Gleason® spur and spiral bevel gear generators. Rather than bore you with details here, visit Ash Gear and Supply. They offer this software and you can read all about it from their Software Page. Or you can visit this website's download page to get free demos for your personal evaluation.
The next installment discusses what Gear Man and the machine operators are faced with at the machine. Most of these situations arise with CNC and Manual equipment alike.
Conclusion
Perhaps this has helped a little to clear up some of the decisions involved in JIT and small lot gear manufacturing.
Buying very expensive CNC gear equipment may not be the answer for every shop. Take a new look at manual gear cutting
equipment through the window of software technology. You may even see an opportunity to recycle some old yet
attractively priced manual gear cutting equipment. Now that's waste reduction!
Bill Simpson
07/03/2006
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