Re: Router plan made from steel

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "David A. Frantz"
<wizard@e...> wrote:

> HI Mina;
>
> Weight is generally not a problem for machine tools. But you can

have

> issues with vibration and stiffness in steel structures if care is

not

> taken. It may be difficult to translate plans for a machine

built out

> of aluminum directly into a steel structure.
>
> From this perspective I would look for plans that are based on

steel

> from the begining. Hopefully they are plans that have been field

proven.

>
> The alternative is to develope a design of your own. In the long

run

> this may be the smart thing to do. I'm not sure if you where

quoting

> me or someone else but I'm not one to believe that steel is much

cheaper

> than aluminum. Often when the end results are produced one find

that

> to get equivalent functionality aluminum is cheaper. But this
> discussion would quickly digress of topic.
>
> Thanks
> Dave

I don't think the materials used for machines and the structural
specs would become off topic.

Aluminum is stronger than steel on a pound for pound comparison, but
aluminum is often 4 to 10 times the cost.

I would hope that one of our structurial guru's would comment on the
differences. But, on the surface, I would think that steel would
offer a more ridgid structure when the designs are similar. also, I
would think that aluminum would be a lot larger for members to
achieve the same strenghts.

but, I also agree that a complete design is better than using one
based on one metal and building it with another.

The Axuus unit looked like it was an all steel platform and only used
aluminim for the risers on the gantry. One thing that table did not
appear to have were any members to prevent racking. Probably not a
problem for wood or plasma.

My design was very similar, 2 inch square steel tubes, 3.16 wall for
most of the frame, some 2x3 square for some parts. I also followed
Les's advice and laid in a corner to opposite corner brace. It was
made by laying a length on the table, and cutting it on the angles,
then pieceing it into the sections and welding. that made my design
look very similar, but with the addition of a large X on the table.

Getting married and moving into a smaller shop set my building of my
table back a little more than I hoped.

Dave

ps: plasma is a VERY smokey process and some form of smoke
handling/removal is needed to keep the shop from getting too filled.
for more discussion, we covered this in depth about a year ago.

Dave