"Region" Question

[heyward43]

I'm using designer to design a fairly simple project but have a question about the region tool. If I draw a rectangle 1" x 2" in designer (depth whatever) is the resulting cut exactly 1" x 2" or is it 1 1/16" x 2 1/16". The graphics seem to draw it correctly in some cases and incorrectly in others. If you look at the project file (included) I started designing on the back of the board. The center rib should be 1/4" x ??". The rectangle is correct but the graphics look like it is 3/8". Compare to the next rib at 1/8" which looks correct. Any answers? Thanks

[hotpop]

I can't imagine what this thing is.

I looked at it from the end and I think your front cuts are cutting into your bottom cuts eliminating material from your bottom.

Maybe go through all your dimensions again.

[AskBud]

Heyward,
Check each one using the "White" boxes, it may be much easier.
AskBud

[AskBud]

Here is what Hotpop saw.
AskBud

[heyward43]

Whoops! I think I sent the wrong version. It is basically a step pyramid and should look like it from the end even though it's about 23 inches long. The region issue was causing me some drawing problems. I think I've figured out the "region" tool. Basically, the white line is the center of the cutting bit. Therefore the actual cut line will always be 1/2 of the cutting bit diameter outside the white line. Tell me if I'm wrong so I don't have to do it all over again for the fourth time. I'll send a file of the corrected version as soon as I finish it. Thanks to all.

[AskBud]

Whoops! I think I sent the wrong version. It is basically a step pyramid and should look like it from the end even though it's about 23 inches long. The region issue was causing me some drawing problems. I think I've figured out the "region" tool. Basically, the white line is the center of the cutting bit. Therefore the actual cut line will always be 1/2 of the cutting bit diameter outside the white line. Tell me if I'm wrong so I don't have to do it all over again for the fourth time. I'll send a file of the corrected version as soon as I finish it. Thanks to all.

A Carve Region is a "Closed" figure, and you have no choice of bits. It will be with the Raster. and should be the dimension you select. The only exception that I know of is the newer version(s), 1.150 in particular, give you the option of a feather being inside that dimension or outside if you wish.

A Vector cut, straight or curved is one that carves down the center of the line.

You can best see these effects when you display grid lines, as you can line up a particular figure and see it in relation to the grid.
AskBud

[bergerud]

I think that the size of the carved region will depend on bit optimization. With no bit optimization, each edge will be 1/32" larger than you drew and the sides will of course be sloped. It you choose bit optimization best, I think it will be the size you want with the sloped sides.

[AskBud]

I think that the size of the carved region will depend on bit optimization. With no bit optimization, each edge will be 1/32" larger than you drew and the sides will of course be sloped. It you choose bit optimization best, I think it will be the size you want with the sloped sides.

Test that theory and let us know how you progress with each setting.
AskBud

[bergerud]

I am glad you asked Bud. I have not carved them but take a look at these 10 1/2 by 1/2 inch squares. The top row of 5 squares are all carve regions with bit optimization none to best left to right. They appear to be all the same. The lower set of squares are 1/2 by 1/2 inch bitmaps with bit optimization none to best left to right. Bitmap shapes like this I have carved and measured. I would say the squares will carve from 9/16 by 9/16 on the left to 1/2 by 1/2 on the right.

It looks like I was wrong about the carve regions. Bit optimization does not seem to apply to them. I assumed bitmaps and carved regions were treated the same.

If we believe what we see, the carved regions will carve closer to 9/16 by 9/16. It appears that a carved region is simply where the center of the bit will cover. You will have to subtract 1/32 from each side. Note also that designer does not show the sloped sides of carved regions . (Changing the hole depth does not change the hole size.)

Bitmaps on bit optimization best are closest to what you measure is what you get.

I will carve these and report if there are any surprises.

[bergerud]

I carved the squares (on optimal) and measured the widths (up 1/32 from the bottom). All of the five carve region holes measured around 0.550. Not quite the 9/16 predicted but all the same size, proving that bit optimization, although selectable for these objects, has no effect.

The bitmap squares came in at

0.535 0.530 0.530 0.510 0.505

where the bit optimization is from none to best. I am sure results will vary from machine to machine but the trend should be similar.

Another wish list item: Please connect the bit optimization algorithm to the carve regions.