Organizing the Tool Room
In this trick, we show the tool room rack we developed.
KISS (Keep It Simple Stupid)...Again
At Qsine we have a philosophy that in manufacturing the only thing easy to make is a mistake; everything else takes effort. Simple jobs can be the worst because it is easy to think "just do this and it's done" but rarely is it that simple and often we miss a step when we are over confident. Simple or complex, metalworking is always 100% or you fail, not 50% and you pass. With this philosophy in mind, a lot of the processes we have developed for ourselves are around the concept of mistake prevention more than a concept of getting it right. To some this seems like a play on words as the two concepts sound like the same thing. But anyone experienced in manufacturing knows that there is always more than one way to do it right but there are thousands of ways to screw it up.
In it's manufacturing operations, Qsine uses two CNC machines: a 4-Axis Okuma Cadet-Mate vertical machining center and a 9-Axis Okuma MacTurn 250 mill/turn machine. Both machines are used for prototypes and most of our "production" is less than 10 pieces and repeat jobs are the exceptions not the norm. As we gained experience with our CNC's, we realized that tool setup and offsetting was the one area creating most of our problems and mistake prevention methods were needed. Everything from typo's to forgetting to offset a tool due to other distractions pushed us to get the programs and tools 100% ready before stepping up to the machine.
The VMC is CAT40 and the mill/turn has a Capto spindle. The nature of our work is that we use a lot of different tools even though we don't use many of them very often. We try and keep tools mounted and the large number of variations means a good stock of adapters. Thankfully, the CAT40 adapter market is very competitive and eBay has helped our cause. The price of many collets and holders are less than the cost of tearing down, mounting and offsetting only a few times; and we even use a Kelch offsetter which is much quicker than offsetting in a machine. Capto is quite expensive but if I can find deals on tooling I will pick them up on spec and throw them on the rack. The result is that for only two machines Qsine has an exceptionally larger spindle adapter collection. This large collection created a couple of problems. First was how to store them efficiently and second was how to keep track of them and find the one we needed easily.
Another problem comes from the tooling in the VMC which is primarily used for building custom hydraulic manifolds and integrated circuits. We have a lot of long tools for deep hole drilling and the cavity tools for the hydraulic valves tend to be long and heavy. The CAT40 tool racks or carts I found commercially all sat the tool upside down, on the taper, in a pocket. This is an unstable position for many of my tools so it is cumbersome to handle them. I wanted a rack that carried the holders "tool down"; that was my first priority. Likewise the commercial racks for Capto are also upside down configurations. The short Capto tri-lobe is really not well suited to this design in my opinion.
Qsine does a lot of fabrication and welding so we tapped our in-house forming and welding skills and design knowledge. Our 3 top priorities for the tool rack were: tool down, high density and high visibility. We think we did good job satisfying our objectives. The high density caused a bit of a problem on the roof module: we used a 14.25" rack spacing and of course the joists in the ceiling are 16". The mounting bolts look a little funny but we secured the module with little problem.
Each tool is cataloged with offset and other information in a database and is given a number of the form 123/123. The first number is the tool number and the second is the holder number. For as many holders as we have, it is still necessary to change holders on occasion. Our programs document the tool numbers and the first 3 digit number tells us which cutting tool to use. The second number lets us know if the tool is still in the same holder. If it is unchanged we have confidence the program should run as it previously did. If the number has changed, we know to use higher caution and watch for adequate clearance during tool changes etc. Our database also generates standard tool subprograms for offsetting the tools when the programs run. Every program is written to call the subprogram before running and this ensures the offsets are entered correct. We also program so each tool hovers a known Z location at 3 inches, with an optional stop. We then use a 3" gauge (or a 1-2-3 block) to verify the offset and ensure the setup is correct before proceeding. The trick is to program the offset check into a move that doesn't waste a lot of time during production (which is generally easy).
The orientation keys on the CAT40 slots are nice but really they are over kill. We formed the edged up to ensure the holders would not slip out on their own. The Capto racks are just over formed so the tool lean back slightly to keep them in their pockets. We have used soft urethane bumpers at both ends to cushion the stops.
The middle rack separating CAT40 and Capto was configured with trays for extended length drills and collet shelves for the various collets we use. The end rack was configure with large flat trays to hold vise and chuck jaws. The large shelf rack is really an evolution of the design. We got the idea to make it modular when we decided to use bolt on shelves. The tool holder plates can also be bolted on (as opposed to welding like our current racks) and this will let us reconfigure for short or long tools on the fly. If we have too many Capto, we will be able to switch to CAT etc. Too bad we did not think of this originally but I guess that is how ideas develop. We originally started with 5 racks and lots of room to expand. We have quickly filled up all of the module space but we still have room to expand. Considering the amount we have put away and how easily accessible it is, I believe we have made very good use of our space.
The photo's don't show our latest improvement which is magnetic tags on the rack to mark home for each holder. The rack is only a little over a year old and we shuffled tools quite regularly in the early days. We still need to shuffle tools once in awhile and making sure people can find the tool where they expect it has been a problem. The magnetic tags used on warehouse racking should solve this problem; they are easy to move and the help ensure every tool gets put back in the right place when done.
Investing in tool holders and an offsetter were the first steps in reducing tooling and offset related mistakes. The tool rack is an investment that helps us manage the whole process. We never actually documented what the mistakes were costing us but scrapped part and broken tools are just part of the equation. Many of the hydraulic cavity tools are made to order and delivery is more of an issue than just price. A job that is in the machine waiting for a tool with a 3 week lead time makes the cost feel immeasurable. Just by pure reduction in "aggravation factor" the investments have been well worthwhile. A process that is working well is easy to forget about and this rack will likely take that status in the future. It may sound funny but the rack helps us manage risks and really it allows us to grow our tool room which is critical to our shop performance.