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Subject: Re: Here's what you'd pay for a cnc pcb mill/drill kit...

From: "ballendo" <ballendo@...>
Date: 2004-03-15

Richard,

Thank you for the reply and the concern<G> Which price?

The answer to most of your questions is yes, with a higher proportion
of "yes's" as you go up the price scale... I've been designing and
building cnc machines for nearly 15 years now...

There IS a reason more expensive machines are more expensive. The
trick is in discovering what can be taken out and what must be left
in, as one pursues a lower price.

One sure way to kill a low cost product is to try to make it do ALL
the same things as the higher priced unit. But sensible design is
another thing entirely. That IS available in ALL sizes and at ALL
price points. My machines are all sensibly designed. Where additional
functionality can be accomodated without undue sacrifice, it is
definitely added.

But if you start making the cable runs larger--just a bit--, and the
table sizes larger--just a bit--, and the structure a bit stronger to
support "possible" added weight--just a bit-- the price is gooing to
go up more than the "four bits" just described<G>

When this happens, either I stop doing it because it's not worth the
effort, or have to stop because the "ends" no longer meet.
Adding "extras" kills far more products than it saves... John ruskin
has a great quote, one of my favorites. It's at the bottom of this
message.

Many things that don't matter in more expensive machines DO matter
when the endeavor IS a business, and not just a means to Busy-ness...
Things which might not be immediately apparent to a casual
inspection, or even to a deep inspection by someone unarmed with all
the considerations.

Some sizes and choices are dictated by "standard" lengths and sizes
of materials. Others by what I call the "anomoly" part. (Which refers
to the one item in any given distributors line which represents the
best VALUE. It can be a COLOR, a SIZE, a TYPE, or sometimes even just
a certain MFR. that has decided a particular item is the one.

As an example, I have spent many days on the phone with many
different mfrs of similar items, and gotten reams of quotes for
things that seem clearly outside the scope of what I "want". All for
this reason-- TO see where the price is lower than the item warrants--
There is nearly always a DIP in the price for certain items. Nearly
always in a non-obviouos place. But a good distributor is not likely
to offer this information. (until you're doing 6 or 7 figures with
them, anyway...)

(I'm elaborating on this point because it is equally applicable in
getting parts for a PCB design, or designing the circuit in the first
place; when low cost is a goal.)

I recently did some boards that needed a low amperage fet for some
switching. In looking over the bins at the local seller, I came
across a part number that I didn't know, but obviously a small fet.
There were three bins of these parts, enough for the small run I
needed to do. And they were dusty! I bought a few, and asked that the
remainder be held while I checked out the few in my circuit. They
worked (after some juggling of parts values) and I saved a bundle,
when I took that slow mover off the distributors shelves at a serious
discount.

Other times the anomaly IS the most popular size. But you may not
THINK that particular size, type, color, or MFR. is the most popular.
So by perusing most of a product line, one can find the GAP part, the
abberration in the price structure and save some money, which can
then be used to lower the price without compromising the product.

Then there are things like box sizes, shipping sizes and weights,
these ALL have the same non-linear pricing, IME. Searching out the
anomalies is a must for a low cost unit. Sometimes this will allow
adding those "extras" you mention. Other times it may preclude them.
As Mariss of Gecko once said, "Every part must have a reason to be in
the circuit, it must pull its weight, and not strain the others".
Well that's more than a bit of a paraphrase, what he said was far
more eloquent. But it meant that if you're going for price, you can't
afford extras unless they bring "something REALLY worthwhile" to the
party...

So feed me your desires as to size and speed and capabilities, and
trust me to find the balance between what you NEED and what I can
give at that price...

Thank you again for the email!

Ballendo

P.S. Here's the Ruskin quote, familiar to many:

"It is unwise to pay too much, but it is worse to pay too little.
When you pay too much, you lose a little money . . . that is all.
When you pay too little, you sometimes lose everything, because what
you bought was incapable of doing what it was bought to do.

The common law of business balance prohibits paying a little and
getting a lot . . . it can't be done. If you deal with the lowest
bidder it is well to add something for the risk you run. And if you
do that, you will have enough to pay for the something better"
John Ruskin (1819 - 1900)

Trust that I would not be promoting this quote if I thought the 500
buck machine was not gonna do what I say it will do<G> I've been at
this awhile and I'm not wet behind the ears. (anymore<G>)
But it's not gonna be a 5kilobuck machine... I have that $5K one too,
if that's what you need!

BTW, Have you ever "played with" the online pricing calculators of
the pcb mfrs. (or shippers) to find the anomaly price? It takes more
than a few tries to discover how to truly get the lowest price...
Especially when your volume is not 500 or 1000+ It's a worthwhile
endeavor, IMO. and can be eye-opening, IME.

--- In Homebrew_PCBs@yahoogroups.com, Richard Mustakos
<rmustakos@a...> wrote:
> Ballendo,
> I am real interested in it at the price! If you can throw in a
kitchen
> sink, I bet I could get my wife to want to buy one to! ;)
> However you design it, please, please, look at any way that it
might be extended, and make sure you don't preclude it (this is my
big philosophy/bitch in software design, which I do). Like Alexandre
said, can it do all that stuff? - Which I think translates to:
<snip>