Re: Hot rolled router frame

Hi Roger,

Been there, done that.....

Generally speaking, before grinding, the material should be sent to
the heat treater for stress relieving. Any significant metal
removal from one side of a piece of unrelieved material will cause
it to warp when it's released from the grinder's magnetic chuck.
Welding will increase the chances of warpage.

The best source of info on this would be the grinder people. They
deal with this issue on an everyday basis. If they don't forewarn
you of these problems, I suggest you find another grinding company.

The grinding guy/friend I deal with (up to 72" Blanchard) will not
even attempt to do grinding jobs of this type unless the material
has been heat treated. Over the years he's had too many unhappy
customers who tried to save by bypassing the heat treatment cycle.

Doug



--- In CAD_CAM_EDM_DRO@yahoogroups.com, "vrsculptor
<vrsculptor@h...>" <vrsculptor@h...> wrote:

> I'm still thinking about building a good size router. My 12X48

mill

> is too small for some of the architectural projects I'd like to
> tackle. I've found a firm in Miami (Smith Hamilton) with a large
> blanchard that could grind the frame for a 60" (or larger) router.

I

> was considering a moving table design using bolted 2X6 heavy

walled

> hot rolled tubing for the table rails with linear slides. I've

never

> attempted anything precision on this kind of scale and would
> appreciate your input:
>
> 1. Is common hot rolled tubing likely to be straight enough as it
> comes from the manufacturer to use or do I need to order something
> special? Is a 5' or 6' piece likely to be straight withing .020-

.025"?

> 2. With a bolt together frame there are going to have to be some
> weldments and holes added before grinding such as end plates and
> bushings through the 2" width for bolts. Will the tube still be
> straight enough after arc or mig welding to grind?
>
> All input welcome... I prefer to learn from others experience

rather

> than my mistakes.
>
> Roger S