Unlike one-time cost savings like a staff reduction or cutting advertising spend, increasing efficiency delivers cost savings over the long term. That makes efficiency gains an attractive option for many shops looking to cut costs during COVID-19.
We recently interviewed machine shop efficiency expert Cullen Morrison, who told us, “I guarantee that there's not a single machine shop on the planet that somebody can't walk into and save 10 percent. For most shops, that number is probably north of 50 percent.”
Here are some of Cullen’s top tips for machine shops looking to cut cost through efficiency:
Get the maximum use out of all your consumables
Two things Cullen always looks at are tool utilization and consumable utilization. Are you really getting all that you can out of it? Are you changing tools too soon?
A lot of companies are changing out consumables like end mills, drills, or coolants, every shift, because that’s convenient. But you should only be changing them out when the tool is actually dull, or there's a mis-load of a part and something is broken. By maximizing use of each consumable, you reduce the amount you purchase over time.
Although you should try to maximize use of each tool, try not to push tools beyond their usable life. Dull or broken tools can be a fire hazard.
Use tools and consumables the way they are designed to be used
Another opportunity to save costs is by pushing tools to do what they were designed for. For example, one of the most common turning inserts in the world is a CNMG432 diamond-shaped insert, double-sided. This insert has eight corners to the center, but many machine shops only use four of the eight corners: the four 80-degree corners.
After using the 80-degree corners, most shops will discard the whole insert. They either scrap it, or sometimes they recycle it and get some money back.
The problem with scrapping the insert after using the 80-degree corners is that there's also four additional corners. The additional corners have a 100-degree shape, which is one of the best you can use for roughing or facing operations. You just need a different holder to hold them. That’s a one-time, relatively small cost. And a lot of manufacturers, like YG-1, will give you the holder for free if you buy their inserts.
By using both sides, you can bring your cost down on the most common turning insert by 50%. In fact, your cost savings could be greater than 50%, because the life of a 100-degree corner for roughing is generally even better than the 80-degree corner. You just can't do square shoulders with it.
A lot of shops lose efficiency by using different tools, when they could be using the same tool across multiple machines. When multiple machines are running the same or similar components, you should be using the same tools. Using different tools for similar processes can add cost, because you have to purchase and stock two different tools. That means you incur the cost of holding the inventory as well as the labor cost to complete two separate purchase orders.
Moreover, if you can consolidate two tools down to one across what you do, then you may get your consumption volume up and negotiate out a better cost from your vendor.
New technologies allow shops to consolidate some of the parts they must buy anyway. Take tool holders for example: hydraulic chucks are relatively new technology that can help shops consolidate tool holders. Compared with an ER collet chuck, you can do almost everything with hydraulic chucks. In fact, hydraulic chucks generally perform better head to head.
In a recent test, YG-1 compared high quality brand new ER collet chucks vs. hydraulic chucks in a drilling application. The customer increased their tool life by 30 percent just by changing to the hydraulic chuck.
Hydraulic chucks help save money, because you can easily switch the inner sleeves. That means you only have to buy one hydraulic chuck, if you buy one of the larger sizes. Then you buy cheaper sleeves, instead of having to buy multiple base holders. Now you have current technology that can hold a vast array of tools.
Reduce complexity in what you’re stocking
Many shops miss out on efficiency opportunities by stocking too many different end mills. If you're running computer-controlled equipment, you typically don't need every 32nd size of end mill. You can do what you need by taking the smaller tool and programming it.
Stocking fewer end mills means you spend less overhead time managing that stock. It also allows you to establish a process. For example, if you make small parts, you can standardize on a single ¼” end mill for all of your stainless-steel roughing processes. That means when you have a new shape, you can apply a profile from a previous job using a CAM system and adjust feeds and speeds. That way, your trained personnel can easily master new set ups and jobs. You can do the same thing on the finishing side.
All of this reduces complexity and allows you to keep essential parts organized and accessible in your shop, increasing efficiency.
There are many other efficiency opportunities beyond these five areas that machine shops can take advantage of. However, these five are simple and effective. Most shops will be able to find an opportunity to improve efficiency by analyzing one or more of these five things.