Re: newbe CAD/CNC question - trying to get past 1st base!

--- In CAD_CAM_EDM_DRO@y..., "mszollar" <mszollar@g...> wrote:

>
> What you are saying is that if I where milling the bottom (as shown
> in the image) I would have a border (representing the outside) and
> (here is where I get lost) 1 rect for the middle and 1 rect for the
> ends or do I want 1 rect for the middle and 1 rect for each

different

> depth milled in the ends? I get lost in the visually there is 1
> rectangle for each end milling, but that rect is (logically) broken
> into 3 rect; 2 outers deeper than the middle.

Here is a suggested process to make this part.

Step1) Square up a block that measures the same at the extents of the
part shown.

Step 2, Clamp the part in the orientation shown, but with the long
dimension parallel to the Y axis. This will assure that you have a
good grip on the part, even after you have removed all that material.
Use a cutter with a corner radius the same as the bottom corners, but
a flat on the bottom so that you can cut with a single tool. Draw a
rectangle that represents the extents that a cutter will have to cut
to clear the U shaped slot. Pretend that it is closed on the ends,
just slightly farther from the sides of the part, than the radius of
your cutter. Pocket this rectangle.

Step 3, Flip the part, , orienting it for tight clamping with the
remaining material. Now start a new drawing, oriented the same way
that your part is to the X and Y axes. Design a pocket that will
clear the slot on one side. Repeat it for the other side (use a copy
or translate command) Clearing a slot is the same as what you did in
step one for the big slot "pocket". You may have to also run a
couple of passes across the top of the two bosses(they point down in
the picture, but will point up in this clamping) that is still
standing. It is not clear whether or not it is flush with the bottom
of the part. If flush, you will have to take a cut on the inside to
remove the radius that is visible on the picture.

The point is that you want to plan your process, including work
holding, then make a cad drawing or drawings that are oriented the
same way.

Best Regards,

Fred Smith
IMService