Re: [CAD_CAM_EDM_DRO] What the hobby CNC industries need!

Partially, ... and your Q/point/request is a good one.
I was about to write such a book a few years ago ... and work got in the
way.

There is a difficulty -
most of this stuff is really, really, easy - in a very specific way, for
a very specific set of needs/desires.

Change anything in a very small way, and the output changes
dramatically, often in a non.linear way, and sometimes with surprising
implications and work/costs related to that.
In a previous life, I have been a somewhat high-end or big problems IT
guy for about 15 years... and the situation was exactly the same.
And the clients never wanted to be told the truth - ie they needed to
look at their needs and not at the server boxes/hw etc.
CNC stuff is exactly the same.

With a large amount of experience, a person with several machines
experience can instantly pick the right answer, all the time. It may not
be the best answer, but it will almost always be very good, and usually
for a fair price, as most of us here have a limited budget and have
learned to be very efficient (not necessarily cheap).

Problems;
The right choice is a matrix;
This means everything depends on everything, and unless the users know
what they want, they cannot get a good, efficient (cheap) solution.
CNC is relatively expensive.
You end up sending at least 1000, probably 2000$, for a setup, at a minimum.
People will read that "I made a milling machine for 100$" ... this is
simply not true.

Most of that 2k$ is tooling, jigs, instruments etc etc.
If you are a tool & die maker, machinist, mechanic etc. and you have a
large set of tools, you can make most anything without buying a lot of
new stuff. You cannot make it cheaper, in general, (at minimum wage say
5$/hr) than buying some of it, but You *can* make almost all of it.

To really have a cnc milling machine you need measuring instruments (DI,
DTI, mics, calipers), tooling (end mills, holders, collets, draw bars),
stock (of known quality metal or material like plastics wood),
hold-down, vices etc. etc. plus a decent spindle, linear system, motors,
drives, wires etc. etc.
The size, qty, and capacity of each varies widely.

2 examples;

1. CNC systems need drives;
For a hobby/learning use an integrated stepper driver kit for 3 axis is
hard to beat. 150$. Will run anything up to a bridgeport full size mill
decently (bit slow but ok).
You can make a somewhat less capable one for 80 $ in parts and 20 hours
work. Worth it - You tell me ?
For most, it´s not worth-while.
If you want to make "stuff for sale" your price is likely to go up for
many reasons- and not just speed. In my opinion, accuracy derived
through tighter gearing is the most important one- some differences of
opinion exist;

2.1 small router
Some people want to "mill" wood, ie make a cnc router.
Great, its fairly easy and works great.
When estimating costs, most people forget about the connectors, cables,
cable chain carrier, boxes, capacitors, limit switches, estop button,
secondary 5v (and maybe 12 v) power supply, extra gfi, pulleys, belts,
etc. etc. etc.
Some people want to make one, just so it runs ... and some want it to be
a tool, if even for a hobby.
This might use flat belt pulleys, skate bearings, 12 v dc voltage, a 50$
router or dremel.
Total cost 300-800$.

2.2
A hobby tool will maybe cost (wood router, small, gantry design, under 2
hp, under 2ftx2ft) 500$ more if its "good and usable".
Acme screws (at minimum), timing belt pulleys, limits and better
drives/electronics and protection make up the difference cost.
So total cost 800-1300$.

2.3
Add 2000$+ for excellent industrial-quality results (drill jewelry,
titanium, under .2 mm drills etc etc).
So total cost 2800$+, at 30k rpm plus, 400 hz spindle, precision collets.
Multiply by 5 if you want to buy it in a store.

1. - is a good worth while project, for learning, and making an
occasional piece like a 3d street sign, etc.
2.1 likewise, but much more money, and could make something at need for
giffts, and some light commercial stuff
2.2 likewise, but you might use it to make stuff to sell at 1000-2000$/wk.
2.3 same, but more income, more expensive pieces

Without knowing what you audience is, and their expectations, the
desires, beliefs, and expectations of every group will diverge wildly.
And unlike most stuff, in this hobby, just a bit "better" or "more"
capacity, will easily increase your "price" in hours and $$ by 8x.

All of these examples are valid endeavours- but the right path for each
one is very, very different.
thus answering questions is often hard, when the questions are generic.



556RECON wrote:

>
> This is just my 2 cents worth.
> This is what the home or do it yourself CNC world needs, I think.
> First a "CNC for the novice" pamphlet or small book. this would answer
> all the basic questions.
>
> I think that there could become a good market for used machines and
> stepper and servo motors and drivers as the entry level CNCers realize
> the should have bought the 400 oz in. instead of the 200 oz in. or they
> want to upgrade to servo motor from steppers. If they are limited in
> their finances the need to sell the old to buy newer, better or bigger
> equipment. I also know the used electronic s market is a night mare.
>
> There is also a need for a Novice CNC forum where there are not any
> dumb questions or some forum etiquette where if you do not like the
> question that someone asks you just erase the post and move on instead
> of making a snobish comment and chasing some one away from asking
> questions.
>
> At the same time a novice should sit back and read the response for a
> while and learn.
>
> There are 12 different forums I belong to. Most of them I just read and
> very seldom post to.
>
> Just my 2 cents worth.
>
> OLD BOB
>
>
>