n2kbod5 - need to know Body, chapter 5

last updated 15 oct 97 - mjh

5) ordering parts

Ordering parts begins with either a Bill of Materials, or a Requisition. If you are working on a specific project, the optimal solution is to provide Todd with a Bill of Materials. Todd can give you a template file for this (it is essentially a two column Excel spreadsheet, with ReferenceDesignator - Illinois Part Number pairs). Mike also has some VeriBest tools that will help.

If you are not working on a specific project, or just need some odd bits, the alternative would be to fill out a Requisition. Mike Haney has a template (Power-Point) file to make this a little easier.

IT IS NOT ACCEPTABLE to just hand Todd a scrap of paper as ask him to "just buy these"! There is too much bookkeeping to be done as it is. You really need to provide a machine-readable file so information can be manipulated effectively and efficiently.

Of course, the above presumes that we don't already have what you need on hand. Certainly, if you are working on a project, you *really* want to generate a Bill of Materials anyway, to document what your project requires. This is just good engineering practice. But once you have that, it may be the case that some (perhaps even all) of the parts that you need are already around...

5.1) parts on hand

We have a rather large number of parts on hand, in several locations:

5.1.1) Todd's shop

Todd keeps *most* of the electronic components that we have available in his shop. Some material is labeled "Stock" and as such you will be expected to pay to replace what you consume. Other parts have already been paid for by other grants, and thus are "no cost" for you to use. THIS DOES NOT MEAN THEY ARE FREE! There is a sign-out sheet in Todd's shop. You must sign for what you take.

Talk to Todd for help finding stuff. The organization of components is reasonable, but not completely obvious. And there is no reason why it needs to be. This is *not* a store. You should be ordering what you need...

5.1.2) Harold's shop

Harold has an odd mix of (mostly) mechanical and (some) electrical stuff in his shop. Ask him if he has, or knows where can be found, that which you seek.

Talk to Harold before taking *anything*!

5.1.3) hall closets and cabinets, etc.

There is a lot of "stuff" (not to be confused with junk...) in the hall closets and cabinets. Todd has a (1.2.3) cabinet list of what is mostly in each. A paper copy is currently posted on the wall just inside his shop. More often than not, however, you will simply need to get the key from Todd and look for yourself. Most of it is pretty old, but there is some really good "stuff" none the less.

Be aware that several of the people working around here are pack-rats; Mike Haney is a major offender in this regard. Don't forget to ask Mike if he has one under his desk...

5.2) sources, alternatives

So, we don't have one and you need one (or many)...

There are three levels, depending on your sense of urgency:

5.2.1) today = RadioShack, Klaus

If you absolutely must have it now, there are at least two places to look: RadioShack (a.k.a RadioShark), for which there are several here in town, and Klaus Radio, up in the industrial part north of I-74 just east of Mattis Ave.

You might also try the ECE storeroom in the basement of Everitt Lab (northeast corner of Green and Wright). They tend not to have what you need, but it is worth the phone call (number?)

5.2.2) tomorrow = DigiKey, JDR

If it is not to be found in town, there are a number of "overnight" component houses: DigiKey (www.digikey.com) and JDR (www.jdr.com) are two.

Buying parts from these sources is expensive, and is to be avoided whenever possible. But if you really need it soon, they are there.

5.2.3) soon = Arrow, Hamilton, Newark, etc.

We have continuous purchase orders with a number of distributors. Todd can give you the current list.

We can also place purchase orders with just about anyone.

But in all such cases, it will take a while, both to get the paperwork processed, and to get the parts shipped. Allow at least a couple of weeks.

Yes, weeks. It is not uncommon for silicon to be unavailable for weeks, it not months. This stuff is not sitting on shelves at the department store. It is being made and used even as you read this. Sometimes we get caught by "the industry" (beit telecommunications, or personal computing, or high-tech toasters) and parts simply are not to be found. You are advised to apply the (4.4.1.2) the DigiKey metric to decide what is "safe" to order. But don't order it from DigiKey, as it will cost too much. If you don't need it tomorrow, order it through Todd from one of his favorite distributors.

The punch line is "order as early as you can".

5.3) who pays...

Generally speaking, if you order it, you pay. And it is yours. Which means you need to keep it.

For certain items which we identify as "Stock" (i.e. items that we want to always have on hand), Todd will order these autonomously, and pay for them using the general engineering account. If you want to use a Stock item, you need to reimburse the general engineering account. (Tom does the paperwork, but the money comes from your grant).

So what happens if you need 5 surface mount resistors, but the minimum order is 5000? Don't worry: they are only $0.01 each, so this extravagance will only cost you $50. Do you really want to store 4995 resistors in your office? You can, of course. They are yours because you paid for them. Don't forget about spares. You definitely want to keep some spare parts for the things you build.

But, as an alternative, you can "donate" the excess to the shop (sorry, no tax break). As they are not Stock items, the next person to come along who needs the same resistors will be able to get them from the shop, gratis. Likewise, if you wish to use a component that is non-Stock, and we have it, that part is no-charge for you as well.

The shop can not be run as a store. We can not afford detailed bookkeeping (every part, every purchase, who used what/when/where/why...). The above compromise is not particularly "fair", but it has two redeeming features. First, it is simple, and therefore will tend to be done correctly. Second, there will be no double-billing (no more than one person will ever pay for any one part). This second feature is *not* present in most other "almost" accurate bookkeeping schemes. It is very easy to over-bill when you don't keep track of who paid...

One other benefit of the above scheme is that it will tend to reduce our capital investment. At present, there is little or no incentive for using parts that we already have. And we have a lot of parts that may never get used, unless there is some incentive to do so.