Some Eagle questions...

[Ryssen]

Some Eagle questions...
Trying to do a schema in Eagle in SMD,riht now I have all the parts except a TL431 SOT 23,I have it in T0-92 but there is no SOT 23 in eagle so I cant make one,how to fix this?They have files on the makers site for the TL431,but not for Eagle. Links for downloading (not Cadsoft) is apriciated.
How do I set the dimmensions on the PCB,if I want a smaller one than Eagle makes,and right now I have 3 layers,what if I want 2,how do I change that?

[jcx]

http://www.cadsoftusa.com/forum.htm

also a Yahoo group


Eagle definitely has sot23-3, maybe not labeled tl431

simplest is just to lie to your layout software and drop a sot23 transistor on the schematic in place of the tl431 and appropriately "miswire" it

[pinkmouse]

Edit the library part and add the SOT footprint copied from another part. It's not difficult, just a little obtuse.

Change dimensions by just dragging the board outline to where you want it. It helps to turn the grid on with an appropriate scale. One of my biggest annoyances with Eagle is that you can't lock layers, as it is far too easy to move the dimension lines once set. Grrr.

Deleting layers, easy way- just don't use the third layer, Eagle won't produce gerbers of an empty layer. Or as long as you have nothing on the layer, just click on the layers button, select the layer you don't want, then just delete it.

[Ryssen]

I think I figured the above questions out.
Now I want to know if it is possible to,if you have a PSU and some other circuit on the same board to make it esay to part the to when the board is ready.Break it in two.I´ve seen this in some boards e.x
the KSA50 boards.