mjdeacon,

I posted a while back about DFMA for low volume manufacturing and didn't have much success in my search thread404-316744: Design for Manufacturability & Assembly at low production volumes however good luck.

I worked for a while in an outfit that made generator skids for offshore and onshore oil production, all custom. They had been doing it for years.

One day they got a hair across their butt about cleanliness, and implemented '5S' or something like that. Basically, they cleaned house, and then some. They gathered up all the little offcuts and other pieces left over from decades of previous jobs, and sold them for scrap. Then, since they didn't need them anymore, they sold their stock racks and now empty storage shelving, for scrap. The money from the scrap dealer paid for a modest pizza party.

Then they got another project. As usual, the specs changed after construction started, multiple times. They had to buy a full length, 20 feet, of a given size of angle, in order to get the couple of feet that they needed. ... and again, and again. Worse, every time they needed a new piece of stock, they had to call around and get bids, wait a couple of days, pay for the small delivery, and worst, find something else to do while they waited.

It was a friggin' disaster.
They delivered late, and lost their shirt.
They are now pretty much out of business.

You may be able to extract a lesson from that.

What I extract is that a company that builds the same thing again and again can predict its material needs, minimize onsite inventory, expedite tool changes that can't be avoided, and stuff like that.

Whereas, a custom shop really needs to have a lot of odds and ends lying around, or better, stored in an organized way, so they have the agility to implement small changes with essentially zero delay, and certainly don't want to be in the position of waiting for any external vendor to deliver a small quantity of anything.

Mike Halloran
Pembroke Pines, FL, USA

The theory is the same but, it is harder to implement for a custom manufacturer... and please don't sell off all of your drop to the scrap guys. That stuff always comes in handy especially in a pinch. Organize your drop and if you have an extremely large amount of it you may want to inventory it.

Start with your 5S Get cleaned up and organize hand tools and perishables at your work centers.
Limit your cycle reduction to wasted operator movements and solve by this by point of use inventory.
Gradually expand to the other waste areas and make sure you sustain as you move forward.

Cut inventory last. Maker sure you can meet production before this step. Late deliveries could cost a customer.

There is a lot of stuff left out here. I can't write a book or teach it all to you in one post.

good luck