Tool crib numbering systems

Who has set up a system they like for tool crib numbering?

I’m trying to figure something out where the numbers mean something, to help me organize the crib and know where to put new mills/bits I buy.

Right now I expect to have separate cribs intended for the router and the mill.

I have now cataloged I think all of my router bits. I have a whole spreadsheet ready to sort. But I haven’t figured out what system to use to assign numbers to the bits… :confused:

Send help! :slight_smile:

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Metric vs. Imperial?
By Collet size?
By cutter type?
By absolute diameter?
By Dewey decimal system?!?

Sorry, I got nothin’. :upside_down_face:


I’m starting to think about reserving 1-9 as aliases to use for bits currently in frequent use, but to systematize in the hundreds, and leave double digits for future organization. Or maybe go to four digits; I don’t know how well various tools deal with four-digit tool numbers. I know “dewey decimal system” was a joke, but really I had already thought of it as an analogy for what I want to do; I’m looking for a system after all.

Ultimately I need an accession number. But even four digits isn’t obviously enough. If, for example, I were to have 1000’s means imperial, then 1XXY could be XX 32nds of an inch shank and Y be an accession number, but that wouldn’t work for ⅛" for me since I already have more than 10 kinds of bits with ⅛" shank; I would run out of 104Y numbers.

I’d like one set of tool numbers across all software I use, and directly address my crib. I don’t have and for the foreseeable future won’t have an ATC. I’d like my T tool strings to directly reference my crib, so I can get a prompt and go straight to the crib for the next bit to avoid confusion.

This is confused a bit because some systems use a convention where a T tool string has a configurable portion that provides or addresses a tool offset. This is commonly used on lathes, I think. But I have no plans for a CNC lathe at this point, and I can burn that bridge when I come to it.


How many bits do you have? I know this is going to sound like overkill, but if you really do have a lot, then maybe a database tracker would be good.

For example: have a 3-digit bin code if you don’t expect to have more than 1000 separate bins. Then, every time you put a bit in a bin, note that bit in the row matching that bin code. If you really want to get crazy, you could laser engrave a 4-digit code on each bit (bits break) and then note that 4-digit bit code in the row for the bin code.

I used to work on Microsoft Access, so I guess it would be fair to retort that my suggestion is a clear example of how when the only tool you have is a hammer all problems look like a nail. :wink:


Even crazier, supporting argument for the above turbonerd idea:

if you have standardized your bins for bit storage, perhaps you could automate the bit changing later.


This isn’t a software problem. In a database analogy, I’m looking for a schema that has worked well for others in practice. Here, the schema isn’t field types and indexes, it is meaning of place values in a number. I’m particularly looking for a schema in which as many as reasonable of the bit attributes are encoded in the bit identifier. I’m expecting the sequence to be very sparse. My point is that I want a system now that will grow as I acquire bits. I have only dozens of different types of bits so far for the router. I expect to fill that out. The bits I have right now are overwhelmingly ⅛" shank. I expect that always to be true for the router since it’s kind of a “sweet spot” for my application (1.5HP spindle, ER11, aluminum gantry and belt-driven with openbuilds wheels so not super stiff), but to fill out other sizes as well over time.

I want to use the same tool numbers across different software. I have been enjoying trying out different software. I’d like T2536 to mean the same thing whether I did the toolpathing in FreeCAD or Kiri:moto or SolidWorks or FlatCAM or Fusion360 or PathCAM or…