Lean Manufacturing

[JeremyV]

So... my company seems to think the process flow is normal for them when as a machinist myself, it's not.  Their idea of "Lean Manufacturing" is this: We have 2 different orders of the same part, and it makes the most sense to complete both while all tooling is there and there are a lot of tools related to the job.  But no, their claim on lean manufacturing is do the one job first, go on to something else then we'll come back onto it in a month or so...

 

So, I gotta ask: what is your definition of "Lean Manufacturing" in your own words?  And are we doing it wrong?

 

-JD

[THEE THAINZ™]

JIT, just in time it is all part of the lean manufacturing plan. How long is your set up time to do the time how much common tooling is there used in that job compared to others? If you can leave your common tooling in the machine you will reduce set up time. A part on the shelf runs the risk of never being bought. Then you will loose time and material times 2. Reason for this is there will be a paying job that will not be done or put on hold during this time.

[Guest MTB Technical Services]

Lean is just a fancy term for Kaizen or 'Continuous Improvement'.

It is the Western World's spin on the Toyota Production System.

 

JIT was a philosophy created by W. Edwards Deming who was instrumental in the rebuilding of Japan's industrial capacity.

In short it means that keeping inventory beyond what is required, when it is required, is waste.

A manufactured part is planned to arrive at each stage of production just as it is needed.

 

JIT, KAISEN, TPS and LEAN all have their origins in the work of Deming.

Deming is the single most respected non-Japanese in all of Japanese industry.

The Japanese Government honored him with the establishment of the Deming Prize in 1951 as recognition of his efforts.

It wasn't until the early 90s that his work achieved any real measure of recognition in the US.

 

In a nutshell, LEAN can be regarded as this:

Any activity that does not contribute to value the customer is willing to pay for is waste.

 

All this aside, the difference in delivery date requirements for the two part orders is critical to the determination.

Your managers might be correct if the second part order isn't required to ship within the same 30 day billing cycle.

If, by completing both parts, you actually delay others from on-time delivery then their philosophy is correct.

[djstedman]

At some point there should be a determination being made as to whether or not there is a benefit or not, if a setup, and subsequent inspection on an operation are more costly than the parts themselves then making the decision to split lots of parts is shooting yourself in the foot.

 

That said in lean manufacturing every effort should be made to reduce setup times and ancillary costs so that the company can in fact get a benefit from lean manufacturing methods.

 

I do think there tends to be a disconnect between management who hear terms like 'Just in Time' and 'Lean Manufacturing' and think they sound great without actually putting in the effort to support the people on the manufacturing floor, without putting the proper effort in to support quick clean changeovers from one job to another on the shop floor 'lean' tends to have exactly the problems it sounds like your running into.

[duckdogers]

I would say if the setup is big and the orders are solid it makes no sense to me to turn around a month later and run the same job when you can run it now.Just my opinion which a lot of times mean squat around here.

[Rstewart]

So... my company seems to think the process flow is normal for them when as a machinist myself, it's not.  Their idea of "Lean Manufacturing" is this: We have 2 different orders of the same part, and it makes the most sense to complete both while all tooling is there and there are a lot of tools related to the job.  But no, their claim on lean manufacturing is do the one job first, go on to something else then we'll come back onto it in a month or so...

 

So, I gotta ask: what is your definition of "Lean Manufacturing" in your own words?  And are we doing it wrong?

 

-JD

 

Yeah, I'm kinda doing the opposite of "Lean" myself right now... 

 

We make several different assemblies that are part of a weapon system.  Currently we are slow and one of my VMC's is setting idle for at least a week or two.  We had leftover material from the last components I machined, so I just decided to start running some more parts.  There will always be a need for these parts, but like stated No paying customer at This Moment...

 

Is this completely bad practice, or am I just a good employee  ??

[Guest MTB Technical Services]

Yeah, I'm kinda doing the opposite of "Lean" myself right now... 

 

We make several different assemblies that are part of a weapon system.  Currently we are slow and one of my VMC's is setting idle for at least a week or two.  We had leftover material from the last components I machined, so I just decided to start running some more parts.  There will always be a need for these parts, but like stated No paying customer at This Moment...

 

Is this completely bad practice, or am I just a good employee  ??

 

If your company has to re-order material for a paying job to replace the material you used for a non-paying job then you cost your company money.

 

Carrying inventory has verifiable costs whether it is raw material or finished parts.

That inventory gets taxed as well.

[Rstewart]

If your company has to re-order material for a paying job to replace the material you used for a non-paying job then you cost your company money.

 

Carrying inventory has verifiable costs whether it is raw material or finished parts.

That inventory gets taxed as well.

 

 

Well, it's a little complicated but I do understand what your saying.   I just Hate sitting around idle sometimes

[chris m]

 

 

Lean is just a fancy term for Kaizen or 'Continuous Improvement'.

 

This is not accurate; Lean Manufacturing incorporates components of many other philosophies (as do all management techniques), but all [3] stand on their own.

 

Why would I run a piece I don't need until next week, when I have a different job that I DO need waiting for machine time? If you ignore setup, this is unthinkable. The key to the whole deal is to drive your business to the point where you CAN ignore setup, and that is the fundamental underpinning of most of these management systems. If you could ignore material availability, and ignore changeover time, you would process each job in the order it was required ALL of the time; working to achieve this condition is our goal in this business.

 

We run to-order, in order quantities (no extra pieces), set up and break down the same jobs maybe once a week, maybe more at times. 

 

If you aren't forced to make the first one right, you'll never improve your processes to make the first one right, and you'll always junk it because it is a "setup piece."

 

If you aren't forced to tear down and set up all of the time, you'll never work to improve your setup techniques.

 

 

This being said, the management of the company must realize that speed costs money; if they don't give you the techniques and the tools and the capital, simply yelling out "Kaizen" every once in awhile will not be effective.

 

 

 

We make several different assemblies that are part of a weapon system.  Currently we are slow and one of my VMC's is setting idle for at least a week or two.  We had leftover material from the last components I machined, so I just decided to start running some more parts.

 

Your initiative is great, but untraceable material used for a "weapon system" is a really bad idea

[Guest MTB Technical Services]

Well, it's a little complicated but I do understand what your saying.   I just Hate sitting around idle sometimes

 

 

I hear you.

 

It's during the slow times I suggest to customers that they have a Preventative Maintenance Plan in place.

The down time can be used effectively and prevent interruptions during peak production.

It's also the perfect time to train for additional skills.

[Guest MTB Technical Services]

This is not accurate; Lean Manufacturing incorporates components of many other philosophies (as do all management techniques), but all [3] stand on their own.

 

 

Sorry, but you are simply incorrect.

 

LEAN is a DIRECT outgrowth of the Toyota Production System created by Westerners.

Every so-called unique component of LEAN has it's origins in TPS

 

My analogy is accurate.

[chris m]

 

 

LEAN is a DIRECT outgrowth of the Toyota Production System created by Westerners.

 

Agree with this statement entirely

 

 

 

 

Every so-called unique component of LEAN has it's origins in TPS

 

Agree with this statement substantially

 

 

Lean is just a fancy term for Kaizen or 'Continuous Improvement'.

 

Disagree with this statement

 

 

Let's not hijack this guy's thread with a semantic pi$$ing war

 

C

[Guest MTB Technical Services]

Agree with this statement entirely

 

 

 

Agree with this statement substantially

 

 

Lean is just a fancy term for Kaizen or 'Continuous Improvement'.

 

Disagree with this statement

 

 

Let's not hijack this guy's thread with a semantic pi$$ing war

 

C

 

Ok, I see what you're getting at.

 

I over-simplified it a bit.

The core principal is still that any activity that doesn't contribute to value the customer will pay for is waste.

 

I would agree that the term LEAN has been bastardized and misappropriated in many areas.

I'm actually seeing it used in software development now and it has a completely different meaning.

[Chris Rizzo]

The absolute core of it all is Just in Time. Customers buy cars one at a time.. Therefor they should be made one at a time. The holy grail is for an assembly line to make 1 blue camry, 1 red suv, 1 silver pickup, 1 prius, 1 white suv, etc etc. one after another.

 

 

Yes it can drive a shop to insanity.

[Newbeeee™]

We have more machines bought and paid for, than are required for our monthly work.

We always have some spare machine capacity (but not much), based on 70hr week.

We can work nights when we need to, or into the night to get a job out.

We have some annual PO's from customers, where we'll buy all the material and make and treat all in one go, and then through the year, pull the parts from stock and deliver.

We break machines down as little as possible, but will do if we need to. OTD is king.

A bad 1/4 will be 95% OTD, where on average (last 5 years) we're running 98%+ OTD.

So as a business, we're probably doing everything we shouldn't do.

[mike93]

imop

 

lean manufacturing is a plan to cut set ups in a algorithm ,to cost less then the interest on inventory  plus taxes per  part per quarter to make a higher profit margin with out one person able to affect delivery of sead part...

[Guyinthedesert]

We have a few jobs that are considered "Filler" jobs. When a machine has nothing scheduled on it, we'll throw a filler job into it and keep it running weather there are orders for the part or not. They go into stock, and when they get ordered, they ship.

 

So, if I'm understanding this right, under lean manufacturing, we would be money ahead to just shut the machines off and tell the operators to grab a broom?

[Guest MTB Technical Services]

We have a few jobs that are considered "Filler" jobs. When a machine has nothing scheduled on it, we'll throw a filler job into it and keep it running weather there are orders for the part or not. They go into stock, and when they get ordered, they ship.

 

So, if I'm understanding this right, under lean manufacturing, we would be money ahead to just shut the machines off and tell the operators to grab a broom?

 

Not necessarily.

If you have empirical data that can justify small levels of inventory of finished parts, it may be a good move.

The final cost to the customer plays a part.

It's almost always a bad idea to do this with high cost parts.

 

However, inventory has measurable costs as well.

The longer inventory exists, costs increase.

By only purchasing the materials needed to complete production when it is needed, costs drop substantially.

[JeremyV]

Thanks for the responses!

 

I knew I was almost going to start a pi$$ing war because "Lean MFG" is opinionated by various people and various companies.  Take it for how you will, but several key points here that we try to do as a company:

 

Standard tooling: Those vary by machine.  in our "CNC" department, we have 5 machines, 1 mazak horizontal, 1 mazak vertical, 1 HAAS VF-6, 1 Kuraki boring mill with 157"+ travel on X and another of the same with less travel.  the smallest tool magazine falls to the 2 verticals so on those 2 machines, we most commonly swap out tooling too often on the non-standard pockets.  On the horizontal, it still happens when we switch orders due to the large # of tooling required to machine the part.  I could go on and on about this, but the main issue we have when all 3 machines are running is the lack of tooling on the shelves.  At the moment, the mazak vertical is down, i removed some tools from that machine so I could have the flexibility of setting up standard tools: 1/4 mills, 3/8 mills for stainless and aluminum, trying to stream line tooling between jobs to make setup considerably less when it comes to measuring tools.

 

Today, I knew a 5/8 rougher was already measured, and i didn't re-measure it to save time. Lo and behold, the tool probably moved so the difference was it got sucked out by about .02 so in the past i've always measured every tool i had for every setup, even the same ones just to be safe and it paid off.  I've watched other machinists make the same mistakes i've made today and this was a first for me so i told my boss that we are going to have to measure everything regardsless if you knew they are measured or not.  Its nice to have a tool presetter on the machine =)

 

  But long story short, the company sees buying tooling as "why do we need it?" They question us a lot based on just that very reason alone when we machinists can actually cut down setup time by possibility setting up the next tools for the next job with available holders sitting on the shelves.  So, ya it is process improvement to have more holders on hand than having to waste time hunting for collets and holders.... more often than not.

 

I try to streamline the work which is sometimes not based on the "schedule".  Management expects us to follow that to the letter, but that is more costly because of teardown + setup and repeat.  We don't do production as on average, the quantities are about 25 parts per order with the occasional 1 part per order.  Its the one part per order that makes things insane between setups.

 

I'd have a plan to somewhat eliminate this idea where you'd have to constantly change fixtures, but of course, that'll need more machines and it'll cost $$, but i believe in the long run, the machines would pay for themselves.

 

Before I typed this yesterday, I reaearched this in wiki.  The other meaning of Lean manufacturing is "flexible mass production".  That is something we don't do, except for a certain product.  I really don't understand management sometimes because when we start on actual production, management wants to continue on those till all orders are finished then we move onto something else.  Sometimes it takes a month and a half to go through them all and they come in either 8 piece or 4 piece sets and orders of 50 per can be time consuming and tying up the machine, but hey if we had a 2nd horizontal with a pallet changer setup like the first one we'd committ that machine only to that product and the other machine to everything else.  Of course, i'm not being heard so, why am i bother trying?

 

I do like the comments here so if theres more, keep em coming =)

[crazy^millman]

Jeremy, I stayed out of the thread and see your exact statements in many many many yes many different places.

 

Here is my take on Lean. Lean never is good or will work unless it starts at the top of the organization.

 

http://www.qualitydigest.com/inside/quality-insider-column/are-you-honeymoon-ceo.html

 

Here is a good article about certain types of CEO's I think it can relate to certain types of bosses and managers as well.

 

www.qualitydigest.com/inside/quality-insider-column/7-things-every-superlative-leader-understands-about-problem-solving.html

 

Here is a good article related to that about leaders.

 

How many people making parts even take time to bother themselves with looking at articles in a Quality Publication? How many people who say they understand Lean understand it is not just making the parts that is important? It is a company wide process that goes through all parts and levels of the organization. When people talk about Lean many are throwing out a buzz word nothing more and nothing less than just trying to sound impressive. I am not saying all are, but the vast majority are just parrots. When a company really gets it and really has a Lean process dialed down no one even realizes it. A true Lean process is self substantiating and carries itself throughout the whole organization not just machining, not just quality, not just purchasing, not just management, but every part and step of the process. ISO is just a buzz work as well. I know many many many and yes many companies that are ISO and have no real clues what Lean even means as part of their day to day operations. You would think an ISO company would be the closest to Lean process and find them sometimes the furthest away from it. They becomes ISO to get the more business that meant, but never adopted the the ideas behind it. Same goes for Lean so many make the claim and call themselves Lean, Kaizen and 6s and Toyota yet all they ever did was put a Shadow board up and put some stickers on the floor. Go look at their purchasing department, quality, engineering and other areas and are they just putting lipstick on the pig or are they really what they make the claim to be. 

 

I say great you brought this topic up and yes many many many different opinions about what it means, but at the end of the day Lean is just a word. Applying words to our lives can be done, but to live a word as part of lives means we are willing to humble ourselves and fix that which needs to be fixed.

[Newbeeee™]

Just to clarfy my above post a little more:-

We have 4x vmc's which have grid plated tables and are identical to each other - as in dowel locations and spindle nose to table.

We have 2x 4th axis that are identical to eachother and can drop on any machine, and the fixtures can be clamped and datums in progs (G10's) so we're away quite quick.

We have 2x robodrills that are the same (grid plates etc).

We have a feeler vmc, where we will be in the next few months, getting 2x others to match so we have a cell of 3 (the robodrills are going).

We have 2x siemens shopturn vdi30 turning centres  -same progs/tools/chucks yada yada.

And 2x prototraks (lathe and mill) so compatibility for the operator between the 2x machines.

So although we make stock etc and parts sometimes without order coverage (anti-lean), we do try our best at set-up reduction and being lean-ish.

That said - as a business we need to be waaaaaayyy smarter with tool libraries (we don't at the moment), but this will start happening when the 3x feeler cell is established, because they will be the 'aluminium machines' (15k spindles) and have 30 tools.

 

Ron - good links.

I like the Honeymoon CEO. I never heard of this term, but I worked for one once who had bought out of liquidation where I was working (job shop). He was a fish on a bike - totally out of his depth and really couldn't run a bath.

He had great delight once in telling me about his 'career', which was 3x top jobs running OEM's (one was a UK helicopter manufacturer) where he had 3 year contracts, and after 1.5years, they wanted to re-schuffle. So they had to pay him to go (basically he was rumbled and got rid of, but I don't think he saw it like this ).

So he made his money by being paid off 3 times. Nice work if you can get it....!

[Guest MTB Technical Services]

It's been my experience that you can get a true idea of a company's commitment to Lean Manufacturing principles simply by observing its IT department.

 

Watch how long they take to respond to anyone involved in the manufacturing side of the company and you'll have your answer.

[Bob W.]

I'm working at being lean. Just ordered my second Makino A51nx HMC that will go along side the first. Across from those two is the Makino PS95 with 4th axis and quick change zero point fixturing. Me and my employees (one full time, one part time) are pretty crammed in this 1200 square foot shop and we can push out a staggering amount of work. The most exciting thing about the new HMC is the Haas HAS TO GO! There simply isn't room for it anymore. Yeah, I'm heartbroken...

 

I can't wait until the new machine arrives later this week. It will be set up as a duplicate of the first only tooled primarily for steel whereas the first machine will be tooled primarily for aluminum. The PS95 pretty much handles second ops which are typically much faster cycle times than the first ops, by design. Next item is a bigger shop, then a cell, then maybe I'll add a fourth employee...

[Joe788]

I'm working at being lean. Just ordered my second Makino A51nx HMC that will go along side the first.

Awesome Bob. Did you get a bigger tool magazine this time? You gonna put a 5th on this one too? Or keep it as a straight horizontal?

[Bob W.]

I stayed with the 60 tools. I gave it a lot of thought and a scenario I could see playing out was machine B with 133 tools would be slammed with work but machine A would be available, so jobs that machine B was already tooled for would be switched to machine A. In short, I could this playing out often enough that it would detract from the value in the larger magazine. Our production is pretty balanced between aluminum and steel so biasing the machines in that way will allow them to work as if I have 120 tools. I don't plan to put a 5th on the second machine because there just isn't that much demand to justify another one. If there was, it would be a decision on whether to put another rotary on the first machine making it a pallet changing 5-axis or add it to the second machine.