Homebrew_PCBs

> "Gotta get some things out tomorrow or I'd look at it tonight."
>
>
> I don't think anyone here is in panic mode for a driver just yet. :)
>

Every day it gets pushed back is another day added on before it happens.
Especially for something like the serial testing, you test quick and then you
have time to redesign if it doesn't work.

> I received my UPS tracking number, so I know my rods and bearings are on
> their way. Still trying to figure which option provides more flexibility in
> the long run; the standard moving gantry technique, or a fixed
> center-mounted plate for various tools with 2-layer sliding platforms.

Gantry has full reach minus the width for the gantry itself. Sliding
platform has half the workable area with the same rails unless you take pains to
mount one direction of the platform to the other in a way that only uses a few
inches, which then puts an interference into the center area. Lose some area
but you gain the advantage of easy multiple tools since they're not moving.
Actually I'd say split table, 1/2 gantry with table moving for one direction.
It's probably the easiest to get reasonably accurate since you can work on
things seperately.

>
> I suppose this is only going to be version one out of probably several
> generations of a machine. So I proably can start with whatever is the
> easiest to assemble. I'm just not sure which one that is though 'cause I've
> never done quite this sort of machine.
>

Build lightly for a first pass or two and expect to decide to change things.

> One thing I would 'like' to have, is the ability to work aluminium. Some
> framework of my first machine will most likely be wood since that is the
> tooling I have now (carbide-tipped). I don't have any metal-working bits
> yet, but I will start piling those up. Aluminium is priced competitive with
> steel locally and is not as dense, making machining easier, lighter and more
> forgiving.
>

In general mild steel is easier than aluminum. Slower since it's harder,
but aluminum doesn't cut as well in general since it's softer. Start with easy
stuff and work up, look at the machining websites. I think some of the other
metals are better at first, like brass.

About everything grinds instead of cuts ok. Plan to hook up the Dremel with
a cutoff wheel or to and play around. When it's aligned well and the rest of
the wheel follows in the cut groove, and only the edge is cutting, a cutoff
wheel is an excellent thing.

> My plan is to use the wooden/scrap-metal version to fabricate aluminium
> parts for a 2nd generation machine; bigger, stronger, faster. Now where did
> I hear that before? Hope it'll cost less than to rebuild 'him'.
>

If your cost is similar then it's no problem, but don't let steel put you
off. It's not much weight if it's used judiciously to stiffen a machine only
where it needs it. Steel everywhere is a different story.

Alan