Stocking my workshop, suggestions for parts to order?

[Regis]

I am about to place a mouser order, and I wonder if I could get some feedback from you guys on what parts to have around in my lab for general use. Common parts that will probably be needed for when I do mods or builds.

For instance, 68k resistors for input jacks, 25/25 elecs and .02 orange drops for bypass and coupling caps, stuff like that.

I am basically a Fender and Marshall man, but generally speaking stuff for building and modding tube amps.

What are your must haves for your labs?

[bob p]

I'm going to sheepishly admit that I intentionally do not keep a lot of guitar amp stuff in stock, primarily because I'm a hobbyist and I don't run a full-time MI amp repair business. I also don't like to repair other people's amps, and I prefer to build my own from scratch. So Instead of keeping everything in stock, I just make a list of whatever I need and special order everything at once for a particular build project. Most of what I do have on-hand are leftovers from build projects where I was forced to buy in bulk.

Sure, I have a bunch of iron on the shelf, and a boatload of resistors and coupling caps, but I prefer not to keep lytic caps on hand if at all possible. I don't go through enough volume to justify keeping those kinds of things in stock.

If and when I do have to repair stuff for other people, I tell them in advance that I don't stock parts so everything that may be needed will have to be custom ordered and they will have to wait. That tends to weed out people who I think would be most likely to pester me.

Another good reason for the hobbyist not to keep stuff in stock is because IMHO things like e-caps are best ordered fresh. I prefer not to have something like that sitting on my shelf for years on end. New is better.

Of course, if you plan to set up a real service shop, or if you're going to be doing lots of volume, nothing I have said would apply to you.

If you do want to keep extra stuff in stock, I'd think that it would be handy to have all of the stuff on-hand for the typical AB763 fender board, and/or a plexi. those parts should take you a long way.

[stokes]

Like bob said,unless you are going to do extensive repairs or builds you are better off ordering parts as you go along,just order extra as you go and build up your supply as you go along.I was lucky years ago when one of my suppliers went out of business and he let me raid his stock room before he wholesaled everything.I got enough parts to build a half dozen amps,and still have a lot left,but still dont have everything on hand,and need to order parts for repairs and such from time to time.I gotta agree with bobs suggestion about looking at a typical Fender or Marshall schem and get an idea of what the common components in most tube amps are.It will get expensive trying to get a supply of trannies,and electrolytics will dry out if left on the shelf too long.I do a lot of cap jobs,but still order them as I need.A look at the schems will show you the common values for resistors,caps and pots,but why spend a lot of $$$ on parts you may never use.Better to spend your money on test equipment and get the parts as you need them.You can find resistors and caps fairly cheap on ebay,so they are easy to stock up on.For these parts you will see most tube amps use the same values,like plate load R's are usually 100k or 220k,a look at some schems will get you there.

[bob p]

that comment about test equipment is a good one. i hadn't really thought about it, but if you want to invest your money in something to have on-hand, its probably a better idea to invest in a good dual trace scope and signal generator rather than a bunch of amplifier parts. you'll use the test gear all the time. who knows when you'll use the parts that you keep in inventory.

[Regis]

Well guys, those are good points. I am like you in that I am just a hobbyist and order just what I need, and whatever I have on had is because I over ordered or sometimes never even built the thing I got the parts for.

It just seems lately when I need a certain part to finish a project I don't have it, like a bright cap or a cathode resistor or something simple.

I thought maybe I could maybe ten of each of the most common resistors or such. You have a point about the elecs though.

[stokes]

Sorry to change the subject here,Regis,but I just want to let bob know,its time to clear your saved messages in your pm files.I just tried to reply and I got a message that your saved messages is full.

[Enzo]

Even for a commercial shop like mine, what to stock can be an issue. I agree a nice scope would be a great place to invest. But I don't think parts and equipment are mutually exclusive. What does it cost to get a couple resistors to you? Now price 100 of them. Not much different. Either way, the shipping will be mostly for the box they come in. You can buy 5 resistors for a dollar somewhere, or buy 100 for about a penny each. $20 buys a pretty big bag of smallck both 400 and 600v film caps. I just make them all 600v. saves shelf space. .02 and .047 are common, but so are .1, .01, etc.

Wouldn't hurt to have a few small caps too, for brite caps and tone stack experiments - 47pf, 100pf, 220pf, 470pf.

Using screen resistors much? Get a few.

Pots? You'er on your own there. There are common values.

SOmething you might not think of - fuses.

I am placing an order this evening for some stuff. Some 1W flame proofs I don't have, some pots, solder lugs (like goes under a screw so yu can solder ground wires to it.), some Vregs. Some of those are for specific repairs, but mostly stock.

[Steve Conner]

Hi guys,

I never really got the "ordering what you need" approach. I like to experiment, and I often don't know what I need till I'm halfway through building the thing! I hate it when I think "what if I used a 470pF cap here" and then realise I don't have one

Here's what I keep in my workshop, specific to tube amps:

Selection of octal and 9-pin tube sockets
Any old transformers I scavenged
A pile of assorted tubes
A bucket of switches and knobs

1W resistors: 82k, 100k, 220k
3W flameproof resistors: 10k, 27k
Sugarcube wirewound resistors: 470 ohm, 1k

Orange drop caps: 0.01, 0.022, 0.047, 0.1uF all 400v
Polystyrene caps: 100pF, 220pF, 470pF
Electrolytics: 10uF, 22uF @ 450V; 100uF @ 400V; 22uF @ 25V

Pots: 10k, 100k, 220k (linear), 1M audio taper, 10k 10-turn (for bias)

Diodes: 1N5408

All of the 1% metal film resistors between 0.1 ohm and 1Meg

steve

[PRNDL]

I'd recommend getting several boxes with little drawers for components: resistors, capacitors, connectors.

For standard values, review the amp suppliers web sites (i.e. Hoffman, Torres, etc).
They usually only stock the basics, while Mouser stocks everything.

There are certain values that you'll use all the time, but after 2-3 builds you'll know them by heart (i.e. 1M, 100K, 68K, .1µ, .022µ, etc). Until that time, you'll waste more money buying big bags of components that aren't used very often.
It might be handy to order 5 or 10 of each the first time.

Most builders have a minimum supply on hand and order what they need for a specific build. For instance, they have an Excel file with all the parts for a 5E3, which they use for both ordering and calculating cost (since parts go up in price all the time). You can do something like this on Mouser.

Many consider buying higher quality components at the lowest price to be the secret to tone. It's difficult to tell what component is the best value (i.e. tube sockets).

Usually this means purchasing from several different vendors (which drives the shipping costs up). For many, it's simply easier to buy several items from one vendor (say transformers and resistors), and other parts from someone else (chassis and sockets) than it is to buy everything from Mouser, which is often the least expensive.

[Regis]

Thanks everyone for the suggestions. Now I have a better idea of what to stock for general use.