Is anyone familiar with lean manufacturing?

[atm3]

I am trying to incorporate the thought of lean manufacturing into the granite shop I manage. Has anyone tried this?

[Jason Nottestad]

Yes, the company I work for works on lean principles. Please PM me your questions- glad to help. I'm also offering a lean seminar through the ISFA mentoring program as well.

Thanks,

Jason

[VThartzog]

Read "The Goal". I took a course at VT on lean manufacturing and a lot of it is determining where your constraint or bottleneck is. To do this you need someone almost doing nothing but tracking times that things take to get done at different stations. Finding this constraint is key and you can base pricing off that constraint. You also need to track for a while to get accurate numbers because we all know every job is a bit different.

Our shop is based on this completely and it's extremely accurate. We can determine how long jobs take at the constraint(hand finishing) and use it to keep the shop steady without many ups and downs. Only downfall sometimes if there is a template failure it can create a lull each through the shop where that job was supposed to be at since actual fabrication is only 3 days in our shop.

[Miles]

We use a barcode piece tracking system. It works for us. The guy that wrote it is selling it now by monthly subscription if you're interested.

Maxigig.com is their website.

[Gabe]

Read "The Goal".

and then read it again and again...

then read "good to great"

[jrjoeyg12]

Definitely going to read The Goal now. We tried to implement Lean practices into our shop about 2 years ago. The principles are great. We found in practice they were difficult to implement. My understanding of Lean is that everybody is capable of working at every station, therefore increasing efficiency. For example, if a sawyer finishes his cuts early, he moves to a polishing station and begins working there. Is that how it really works? I understand the bottleneck of the shop, and we are always trying to avoid that. What do you do to fix a bottleneck? I'd be very interested in your seminar Jason.

[Gabe]

its not that you "fix" a constraint, you schedule shop throughput based on your constraint.

[Kris Jorgensen]

Part of lean manufacturing should also be looking at the way you order supplies. The idea is that you keep a minimal quantity of inventory on hand at all times. I've found that this doesn't work for me in the granite business since I keep slabs in stock to show customers. It would work for shop supplies and tooling, but I have not implemented it yet. We have been implementing it at NSI Solutions though. We use the Kanban system (look it up on Wikipedia if you want to know more about it. What we do is look at each item that we have to order from another supplier. We look at the lead time, minimum order quantity, quantity level price breaks and reliability of the supplier. Given all that information we determine our standard order size, and the level of inventory at which we would need to re order.

We use a 2 bin system. Here's how it works. Take a certain screw that we use for example. They come in bags of 100, so 100 is our order qty. Our supplier is reliable and always has them in stock and they arrive 2 days after we order them. From looking at past sales we know the maximum amount of these screws we would need in 2 days. Let's say that's 10. So, we put all the screws in a bin except for 10 which we put in a separate bin (or zip lock bag which we keep in the same bin). In the bag with the 10 screws we put a Kanban card which give us the supplier that we order the screws from and their contact info and our order quantity. The card also tells us the qty that goes in the second bin. So now when the guy in the shop needs 6 of these screws and there are only 14 in the main bin, he has to open the zip lock bag (re order point). He takes the card out of the bag and gives it to purchasing or a bin on the purchasers desk where these cards go. The guy in the shop continues to use the remaining screws from the bag and before they are gone, the shipment of 100 new screws arrives. When the shipment arrives, 10 go in the bag with the card and the rest in the main bin.

Screws are kind of a bad example because it's such a low cost item, but the concept will save you money in inventory costs when applied to more expensive items. It will also ensure that you are never out of an item that you need (once you get all the kinks worked out). You could apply this concept to blades that you use in the shop. Maybe you order 10 at a time, but need to re order when you get down to 2. So take 2 of them and zip tie them together and tape a Kanban card to them and put them in the same place as the rest of the blades.

As mentioned in another post, cross training is also important. In addition having a simple process in writing for every operation in your business is part of Lean manufacturing. This allows you to pull any labor in and get a job done since anyone is able to follow the simple instructions with pictures. This doesn't work as good when you are manufacturing a product like stone, but it works great when you are building/assembling tools.

[jrjoeyg12]

Kris, I love the idea of KANPAN and ordering supplies only when necessary. But, like you said, this doesn't seem to help in our stone shop. Most of our tools are low-cost items. It sounds like LEAN is not really working for your fabrication shop and moving stone forward, it just works for ordering supplies. Did I read into your post wrong?

Gabe, what does that mean to schedule throughput based on the constraint? I've found that if something is heavy on handwork, like miter fold down, then the CNC is light on work because everything we cut goes to the polishers. The opposite is true if we cut a lot of CNC work and it is slow getting to the polishers. How do you get around that?

[Gabe]

Hi Joey- give me a call tomorrow (330-844-4098) your question does not lend itself to an answer that is easily explained via a forum.

[jrjoeyg12]

Hi Gabe, thanks for offering your help! I am currently out of town but I will call you when I get back, if that is ok. I'm ready "The Goal" as we speak so I should have some better understanding when I talk to you too.

[mark s]

There is another approach termed "Quick Response Manufacturing".

https://www.engr.wisc.edu/centers/cqrm/

Incorporates lean mfg priniciples but adds a focus on rapid turn around. I worked at a capital equipment OEM when we went thru the process and we reduced the time to build our flagship product from 6 weeks to 2 weeks and saved a bunch of money along the way to boot. I run my granite shop with the same principles.