inventory system part numbers: building the perfect numbering system?

HI guys,

So I'm pondering picking up an inventory/MRP system to help get a handle on things.
(I'm looking hard at Fishbowl, but if anybody has any suggestions for a similar system that can integrate with Quickbooks, and knows from manufacturing, I'm all ears.)

Anyway, no matter what system we go with, I'm going to have to come up with a system of part numbers for all our parts.
Currently, we've got a pair of mutually incompatible systems that just sort of happened as we grew, and neither one of them is particularly well designed for future growth. So they're both going to get either replaced, or heavily modified going forward.

I've built 2 inventory systems before, for prior companies, but both of those had other needs and criteria than we'd need for a manufacturing shop, so the experience is useful, but not absolutely the same as this one.

As far as part numbers go, there are two patterns that I've seen:
A)"A number's a number". So you start out with a few general prefixes, like "100.xxx" are screws, "200.xxx" are buy-ins, 300.xxx are manufactured parts, etc. Then parts within those categories just add in sequentially over time, regardless of what they are, or what they're a sub-assembly of.

B) "The numbers mean something" So there's some sort of logic to the numbers, to aid people figuring out what items relate to which other items, and to at least be able to make a stab at figuring out what an item's PN *should* be. (Aids in DB sorting too.)
For example: product 125.005 has sub-assemblies, so they'd number out as 125.005-100, 125.005-200, 125.005-203X, or whatever.
Or screws: 1/4-20x7/8 flathead = "250-20-875FHSS" and so on. So if you remember the suffixes for the heads, you can pretty well figure out what the number should be, without looking it up.

The problem with a system where the numbers mean something, is future proofing it.
Sure, I can put all my current parts in, but what if I come up with a new product? Or rev an old one? That kind of thing.
I've done variations on this kind of thing before, and I always leave space between the numbers, but that's the best trick I've been able to come up with so far.

Anybody got any better ideas? Things that really worked? (Or didn't?) Boobytraps hiding in the weeds?

Any ideas gratefully received.

Regards
Brian

Alberic said:

Anybody got any better ideas? Things that really worked? (Or didn't?)

Any ideas gratefully received.

Click to expand...

Letters are base 26. Numbers are only base 10. A combination is versatile.

Think sorting and partial query or wildcard in the system.
Is FHSS on the tail good? Ease of use and how to find things fast.

Thirty five years ago I created a part coding system.
I read the, then current, authorities, which are now c60 years old!
When I retired there were 18K+ parts in the system.

Some historical references, probably not worth your time.
Opitz.
Houtzeel.
Brisch.
Brigham Young University Part classification system.
MIClass

Perfect part coding system, I do not believe this exists.

"For example: product 125.005 has sub-assemblies, so they'd number out as 125.005-100, 125.005-200, 125.005-203X,"
The problem is 125.005.000 and 499.823.014 can be the SAME part.
Some of the authorities, quoted above, provide examples this and of reducing the number of items stocked by up to 30%!

Current resources (who want to charge you) with brief, helpful, details of current thinking, plenty more available on the internet.
What is the Right Part Numbering Scheme for you? Intelligent vs. Non-Intelligent | Arena Solutions
Part numbering system best practice

I was involved in Automotive, I copied part of the Ford system, example.
6789076 928F-10239-AD
6789076 was the FINIS#, Ford International Numerical Identification Number, this was used for part movement, accounts and control. Appeared on the label, not the part.
928F-10239-AD, this was the part "number", used in engineering. Moulded, etched, stamped or otherwise present on the part for replacement purposes. Also the drawing reference.
92 - Year introduced
8F - Original model,
10239 - Part reference, this was not always 5 numbers, letters were also used in this section, not always 5 symbols.
AD - The version number, alphabetical AFAIK.
Ford changed their system at least once prior to the adoption of the above, very old part numbers consisted of six digits!

I used a seven digit part number, no leading zeroes, the final digit was a check digit. I used ISO 7064 Mod 11-2 to create this, wrote a little program to calculate it.
This format reduces the available numbers by c15%.
Also minimised the errors.
Simple and partially foolproofed for purchasing and stores, easy for the part number issuer, it may be all you need. But I doubt it.

We also needed an internal system.for our own parts. Maintained by the drawing office, used an Access database, cross referenced the 7 digit number.
System assumed that subtractive manufacturing would be used, could be modified to include fabrications.
Class 2000352-2766 Cylinder. Properties - Length, diameter, tolerances, material, finish.
Class 2000252-1532 Cylinder with concentric circular hole through. Properties a) Inherited from parent b) Internal diameter.
Class 2000252-2309 Cylinder with eccentric circular hole through. Properties a) Inherited from parent b) Internal diameter, eccentricity.
Work involved. Does not include sale quantities or packaging.
Should prevent stocking identical "spacer" and "bush" coded by their "name".
Class members need drawing only once, parameterised.

"I always leave space between the numbers" So did I, eventually it seems, you have a choice with breaking the system or starting again.
Do not expect any thanks from those using your system, do expect criticism.
Best wishes.

"Boobytraps hiding in the weeds?"


We keep chasing hardware problems where a 10-24 x 3/8 round head may be used in 20 different assy's and though we may have thousands on the shelf for product "A" bases on the last 2 years sales we are out of them for product "B" as the sales of that are 5X what they have been for the last several years. Our operation is small enough we can grab some from the other box and replace them later.

kustomizer said:

"Boobytraps hiding in the weeds?"


We keep chasing hardware problems where a 10-24 x 3/8 round head may be used in 20 different assy's and though we may have thousands on the shelf for product "A" bases on the last 2 years sales we are out of them for product "B" as the sales of that are 5X what they have been for the last several years. Our operation is small enough we can grab some from the other box and replace them later.

Click to expand...

Why is standard hardware given a unique drawing number for each assembly ?

In our case we have bins of hadware for a family of products in one place, we take the machined parts to the hardware for assembly keeping the hardware within easy reach. In trying to keep a "family" part number for each it needed a unique number, though were we to do it again we wouldn't give as much concern to a family of parts to have a "family" part number but rather give those parts only a suffix type number.
Now we find oursleves more interested in winding things down some than building it up we may abandon it completly as with only two of us here we can remember to put things on an reorder list in time to get more.
Hindsight being 20-20 we should have spent more time researching things beforehand.

ManicMetalBasher said:

...
I used a seven digit part number, no leading zeroes, the final digit was a check digit. I used ISO 7064 Mod 11-2 to create this, wrote a little program to calculate it.
This format reduces the available numbers by c15%.
Also minimised the errors.
Simple and partially foolproofed for purchasing and stores, easy for the part number issuer, it may be all you need. But I doubt it.
.

Click to expand...

I like this error checking.
What is the max size for part number when speaking to others?.
Six digits seem to roll of the tongue and easy to remember. Longer one are refereed to as a piece of the number, usually 4 digits or 4 digits and a nickname.
Long "grouped" part numbers can be confusing. Who has 99 billion part numbers to track?

Part numbers are not just about computers, some code and ease of sort in a spreadsheet. KISS, think humans and not how the computer can handle the database.
Many messes are created by thinking to much about data processing or nice neat rows and columns while ignoring real world use.
Bob

I prefer part numbers that mean something

I worked for an electronics company with an alpha numeric system, so once you knew what you wer looking for, you could guess the part number

1700174 might be an old ttl logic ls174, 1700174n might be a burned in ls174

1963216a might be a pan head 6-32 1 inch long[16/16ths]
b might be the flat head
ANd you already know something, 17 is an IC, 19 is hardware


It is never perfect and there will be exceptions, like when some specialty hardware needs to be added[brass 10-32 pan heads with a black painted head]

The advantage to this is when you have 1 million part numbers, and you are trying to find a part number, you already know it.

IT avoids having 16 part numbers for 1/2 inch 10-32 screws because people got too lazy look up the number


when part number 10001111 is a 10-32 screw and part number 10001112 is a sheet of plate glass, how does one figure out whether an item has a part number already?

Cars I own have alphanumeric numbers based on what car the part was first used on. This makes sense as cars are designed in a chronological manner, those trim screws came from what we already had etc.

I worked at a medical implant manufacturer that had a pretty efficient 6 digit part number. XXX.XXX. Family number with a period followed by the length in that family. In the machines, the part number was entered into an unused tool offset. We had a main program that disected using Macro B, that part number and used it to call the sub-programs for the specific length part. All changing Z Axis values were driven by Macro B variables. All the operator had to do when changing part families or part lengths was add the part number into the tool offset and press cycle start. This was pretty close to a perfect numbering system.

Edit: I wanted to add that this system started with using Macro A back in the day. The older Tsugamis (80's era) used this method until the late 2010's.

Paul

Do you want a part number, or a description? As said above, meaningful part numbers will always have exceptions and conflicts once you have enough parts in the system, which means you still have to look up the part number for every part to be sure. Just make part numbers sequential and make them easy to look up.

Look at the way Helical Tools does it. They have a cutter called "HEV-R-70500-R.030"; but that's not the part number, it's the description. The part number is 27287. You can look up the cutter by either term.

A) is the modern way to go, B) is well ingrained but really it made sense before computers.

Trying to get ongoing enforcement and training to read it makes B a fail waiting to happen. With A), there is nothing you can convey in a part number that can't be much better stated in one of a virtually unlimited number of fields you can have.

Whats more, in about any modern MRP/ERP I've looked are, there are no separate products, sub assemblies or parts tables....they are items. Items can BOMS, processes, source, flagged to appear in the catalogue etc, but they are all still items....that just makes it a bit dysfunctional trying to code meaning into them when a product, part or sub assembly is really just a line and number from one big database.

With the advent of databases I prefer meaningless part numbers because it's so easy to search based on other attributes like Description, Where Used, Project Number, Manufacturer, etc. As others have mentioned, unless you make a very limited range of parts a "smart" part numbering system is bound to end up broken by exceptions you didn't think of when conceiving it.

The downside of this is your customers probably aren't going to have access to your database so for them intelligent part numbers make more sense. For most of us this isn't an issue because our part numbers are only for internal use but it can be if your customers need to know your part numbers. For example, there's a company called Item that makes aluminum extrusion and all the fasteners and accessories that go with them. Their catalog is huge and they use meaningless part numbers. This makes it a real pain in the ass for a customer to use. This is one of the reasons we went away from their products in the machines we design and went to a different supplier that uses meaningful part numbers. It just took too much time to find anything. All that said, if the part numbering system is only for internal use then simple sequential numbers with no meaning is my preference.

IF one puts the meaning in the description one has to start enforcing coherent descriptions

Oh that is going to work

part number 56050505 screw, shc 10-32x3/4
part number 78050607 10-32x.5 socket cap screw
part number 99632476 1/4 inch 10-32 allen head screw


now those should be easy to find.....

IF you knew that a 10-32x1/2 shc screw should be part number 21103208, nine times out of ten it will be that, then the confusion is only in the exception, rather than as the rule

humans are not, in fact, computers

Look up something on mcmaster carr, than try it anywhere else and see why good searchable databases are in fact, the exception, not the rule

The last couple places I've worked use a numeric format of xxxxx-x-xxxx. The first five digits are a sequential part number. Every new part gets the next number. The middle digit tells you if it's a mechanical part, a circuit board, software, an assembly, a document or a variety of other things. Use two digits there if you need to. The last four digits are for variations, however you like to use them. If the part is a type of screw, a whole range of sizes could be covered by the last four digits. It's for anything where you want to keep the same base number but have some difference documented on the print, say different finishes or whatever. Now, only hire people who can keep a ten digit number in their heads for more than 7.5 seconds!

At Lawrence Berkeley lab the buildings are simply numbered in the order they were built. It follows no logic as they were scattered at a distance around the hill at convenient spots that had some flat arras already for parking and access. they tend too be close numerically in an area then jump to another area then back and so forth. Building 84 was as High a number as I knew.
Bill D.
PS: Building 80 was numbered way out of sequence. It should have been #40 or so. It was called 80 because it was the control room for the 184" cyclotron, biggest in the world at the time.

ManicMetalBasher:
Wow, thanks for the references. I shall have to go digging.
The good news is that for now, it's mostly just me, my XO, and bookkeeper who'll be messing with this, so the whinging will be minimal.

Thanks,
Brian

General reply:

Thanks for the replies. You've given me much food for thought.

In regards to the person who had the 'kits' of screws and gear on the shelf for putting particular assemblies together, and had the same screws in several kits.... Yeah, that's what we do now too, and the problems with being out in one kit, but not in another, and not realizing it are part of the reason we're switching to something a bit more systematic.
I agree: think twice, number once. Which is why I'm asking around before I commit to anything.

This system would be entirely internal. One of our two incompatible systems is a customer-facing PN system that they've been using for wholesale orders for years. They know it, so it's staying, at least for customer facing stuff.

Again: many thanks for the thoughtful replies.

Regards,
Brian

Quickbooks enterprise can handle an unlimited number of items

I used to run enterprise, but it was always more than I needed and they then put the features I needed into Premier, so last year I finally ground through the process of downgrading. I really never looked at the complexity of multi user permissions and such

It is possible that you could simply run a different 'company' of inventory items that did not include the financial information of the rest of the company.......i dunno..........

#1 Correction to my #4, FINIS, Ford International Numerical Identification System!
Hits head with palm of hand.

#2 CarbideBob (#8)
"Long "grouped" part numbers can be confusing. Who has 99 billion part numbers to track?"

Nobody, but decade(s) ago I read that the world's largest collection of engineering drawings belonged to the US DOD who then had over 250,000,000 drawings. Cannot be coded, even if only one part per drawing, in seven denary digits.

"Part numbers are not just about computers, some code and ease of sort in a spreadsheet. KISS, think humans and not how the computer can handle the database.
Many messes are created by thinking to much about data processing or nice neat rows and columns while ignoring real world use."

The philosophy I developed from my reading, decades ago, was that the priorities were :-
#1 To make the system as easy, reliable and error resistant as possible for customers.
#2 To make the system as easy, reliable and error resistant as possible for the staff who used it all day, every day.
#3 If the administration staff, who created the part numbers once, who modified BOMs occasionally, were inconvenienced by providing #1 and #2, tough.

Like everything else we have it easy today. Every authorised person can, using a part label, a part # on the item, a batch number, a serial number, an item reference on an invoice, can access, in seconds, BOM, exploded diagrams, photographs, videos, warranty terms, etc.

#3 EG (#2)
"Letters are base 26. Numbers are only base 10. A combination is versatile."
Correct, however O can be (and in practise, is) confused with 0, B 8, S 5, Z 2, I 1.
Not recommended in the literature I have read, which, as already noted, is not current or complete.

#4 diggerdoug (#6)
"Why is standard hardware given a unique drawing number for each assembly ?"
I have no way of knowing whether this is common in the USA or anywhere else.
AFAIK the "authorities" advise that every different (= non-interchangeable) part receives a unique identifier, or in the system I described, two identifiers, one for the accountants/stores/purchasing, one for the engineers/production.
This was easily handled in the BOM software I used 25 years ago, there must have been improvements since, unless the accountants now tell the engineers how to do their job.
Full disclosure, I have plenty time for engineers, accountants not so much.