CAD newb

[Dr_Doggy]

so I want to start getting pcbs made for me , so i can throw out all this telephone wire, but after reading on i found Express Schematic and express pcb, which i thought was great , so i could draw schematic and export to a pcb design, not the case, and it seems that the link button is much like the useless box, and if i read the mail properly from the providers it said i could not do it like that, but could not take the time to help orientate me.

So back to google, and next downloaded OrCad CIS v16.6, i could even tell during install , very powerful software, very cool, but I think i have problem with library s and footprints, and cant get schematic exported to pcb.

After that i tried Autodesk Electrical , which autocad vendor recommended, and good cos im trying out autodesk for 3D printer cads, but i think this software is more for electrical, as i found that there few options for electronics, specifically i couldn't find transistors.

I dont even really need spices, I just want to draw schematic, then have software convert to PCB, then maybe move a resistor or 2, then save as format that is common to most vendors, especially cheapees!

i dont mind using what i have, or getting something else, all i really need help with is a basic hello world schematic.. with battery, resitors, switch , caps, diode, inductor, transistors, just basics to get started...


..?

 

[DerStrom8]

Personally I'd swear by Eagle. I started with ExpressPCB but found it was very limiting, and restricted you to using their board house. The next day I installed Eagle and I've been using it ever since. Linking a schematic to a PCB is very simple. Just remember that no program is going to take a schematic and convert it to a fully-populated, fully-laid-out PCB. You need to do the component placement and routing yourself. Some packages offer autorouters, but they are mostly garbage and I highly recommend you stay away form them--they are generally very sloppy and over-complicate things significantly. When you create a PCB from a schematic in Eagle, you're given the outlines of all of the components, along with "airwires", which are just little yellow lines showing where the different pins connect to each other. Then they disappear one-by-one as you route the connections they show. It's a great tool.

Other options include KiCAD and DIPTrace, though I don't care much for them personally.

 

[ronsimpson]

I also use Eagle.
You can get help on the forum for any CAD software.
All CAD software is hard to get started. The first couple of days are brutal. Then it becomes easy. Just when you think all is good the software will drive you to drinking.

 

[JonSea]

Check out this **broken link removed** by Dave Jones of EEVBlog fame.

Drawing the schematic is only half the battle. When you export the schematic to a PCB layout program, you get (hopefully the right) footprints connected together by what Eagle refers to as "air wires". It's up to you to position the footprints on the board in a logical arrangement that suits the circuit, and to route traces between all the pads connected with air wires.

It's a lot like solving a puzzle, and frequently involves ripping up traces and moving components around to get a working layout.

 

[Dr_Doggy]

2 votes for eagle is all i need, Ima make that 3! I was able to complete sch and pcb in 4 hrs, just a small circuit anyway and was very simple and smooth to use, i like also how it shows you footprint and dimensions as im selecting part, and when you get a node error it points you right at it, and i had no problem placing components, it was like i just had to throw them in there, especially compared to my old method!, one thing i did notice thou was that after i annotated the design and my wires turned blue and red (im guessing those are layers), it did not reassess after i moved a component, even if i tried to re-annotate, so moving component meant i had to watch that nodes did not cross or over holes, also i couldnt create new "elbows".

And after this hangover i am starting to familiarize with these autodesks , one thing i worry about though is compatibility, is there generic form i should use when sending to a 3d printshop, i noticed that just exporting from fusions .igs files into Inventors .ipt or .iam, was able to copy shapes, but failed when copying over the cutout shapes(i just found out it was something to do with parent hierarchy in inventor), testing now i can't remember specifically why i didnt like inventor, but i m going to give it another shot, i foresee having a problem when i need to get in behind a shape when its blocked by another shape, plus i will need lots of plains which i will want to show randomly only when working on the objects..?

this is all very cool, and since im on topic anyway, i was asking in another post about G & M and MACHINE codes and such, i just wonder do my cads work with those systems aswell, also i have seen alot of diy xyz plotters and also wonder how the computer outputs that to their micro controllers, ie, usb connection & output encoding format, would it be hard to do my own?

and one last thing!? about servo motors.. i have been searching for good servo, but i notice that for a cheap one its • Speed (sec/60o): 0.16• Torque (Kg-cm): 4.1; so with torq if i have a arm that is 10cm long it will stall with 400grams at a horizontal plane? and takes over a second to do a 360 rotation? I am thinking of a hexbot plastic design, so 3 servos per leg, but i would like it to be a little faster than what iv seen on youtube, maybe even enough so it can do a hop and lift off ground a bit, but how would i math that, when i calc the mass on servo
do i just use the weight of the leg, or do i measure the weight of entire body on servo, or do I measure 1/6(or 1/2,on 3 legs) of body weight? and how fast is enough to do a hop? thats prolly unrealistic, but i would still want it fast enough to seem more instant(kno wat i mean) would x5 or x10 be adequate, also my range is over 180 deg, closer to 275. Maybe i should start thinking about different motors? I am fascinated with those new piezo motors, especially with their feedback response, but that is fur shure through the roof .

 

[JonSea]

...one thing i did notice thou was that after i annotated the design and my wires turned blue and red (im guessing those are layers), it did not reassess after i moved a component, even if i tried to re-annotate, so moving component meant i had to watch that nodes did not cross or over holes, also i couldnt create new "elbows"....

This is kind of a key point, so guessing about "red and blue wires" suggests some time with the documentation, Dave Jones' tutorial on PCB layout in general and some Eagle tutorials would be a good idea. Laying out a circuit board is a complex task and it's too expensive and/or time consuming for much learning by trial and error.

 

[Dr_Doggy]

tutorial watched, good idea, this is amazing, it can even create part lists! and I also was able to contact printshop who were able to clear up those compatibility issues!

 

[Dr_Doggy]

here is first schematic, hows it look? i hope the holes are in mm

 

[JonSea]

Posting a PDF of your board would make it easier for people to look at. Most people shy away from opening rar files.

 

[DerStrom8]

Posting a PDF of your board would make it easier for people to look at. Most people shy away from opening rar files.

Yes, either that or use a simple zip file. I generally don't trust rar files, and I'm not even sure I have a tool for opening them on this computer. Windows has native support for .ZIP, but not for .RAR.

 

[Dr_Doggy]

oops, here we are


since im here i ll show my first 3d cad too, but dont tell, its secret!
lol, kinda looks like a mini tesla coil

 

[DerStrom8]

Ok, I'm just going to mention, try to avoid diagonal wires on your schematics. They look very sloppy and are extremely difficult to follow at times. Try to keep them straight, with 90 degree corners.

Also, am I blind, or did you forget to add your .sch file to the second attachment?

 

[Dr_Doggy]

sry , got ahead of myself there, the second attachment is not related to the first, just something i did in autocad inventor,

i never got pcb or sch done for it cos wire carry 5amps ,and simple enough circuit, idk how thick i should make the copper on the board, usually i find a copy of the awg table when i need to know that stuff

 

[Dr_Doggy]

ok here is pcb! I chose the right sized caps this time , and had no trouble designing my custom parts, and silkscreen was np, but i decided to leave it out since it caused too much clutter.
Buts whats all this about the pricing ? hobbyist can only do 10 x 16 mm sheets, and i cant commercially produce, unless i get standard?
Or i upgrade to Light which is only 2 layer, and only 1 schematic? does that mean i can only have 1 project at a time?

lol could we please confirm my units are mm!?
also what is benifates of using copper pour? should I?

i found cheap board house, http://www.custompcb.com/, for only 80$ i can do 25 of these, i just want to hit the send button, but i fear there is something im forgetting, how does it look?

plspls i wanna hit send soooo bad!

 

[ronsimpson]

Should I be really picky?

C3 is on top of pad, C1 on pad,
D1,D3,C8,C7 touching
T1 and a LED are touching, C13&C7&C8 touching
You have Q-transistors and T-transistors.

Here is something new. There is a button "smash" "separates name and value from a part". A part has a "+" in the center of the part where you pick up the part to move it. Push the smash button then clock on a part. Now there is a "+" on the "Q4" so you can move it with out moving the part. There also is a "+" on the "2N2222A". This way you can move the text around to a better position.

Some people like the part number under the part and some really don't like that.

Good first board!

Also another new idea. If you use the "name" button, in SCH or in BOARD, you can name nets. Now your nets are in the default format. "N$26", N$27" etc. You can have names like "supply", +5V, "gnd", "BofQ4", Don't go wild but at least name power and ground and anything special. When you are laying traces it is nice for the name to pop up and announce "+5V" so you can make the trace thicker. A little trick to help you know what trace you are dealing with.

 

[JonSea]

If your board is 100mm x 100mm or less, you can do far better than $80 for 25. Elecrow has a green only special 10 boards for $15 plus about $10 for shipping. I can't open Eagle 7 files so I can't see the size.

 

[Dr_Doggy]

Picky is good when in training!, I had noticed some of those overlaps mentioned, and fixed the ones i had to, but figured most of the white layer wasnt important since it is not silkscreened yet , and prolly wont be with this one, also i "faked", transistor T1 is actually a TSOP photo transistor, but that was closest i could find. Q1 is pnp T's are NPN.

lol, i originally panicked when i saw most prices starting at 400$, and that it was per mm2 which is the reason for all the compressions, I will try Elecrow next time.

Also again my whole interest in this was sparked with the 3d plastic modelling, I am guessing this is the cheapest way for low vol plastic molding, I am wondering if there are any other resources like this, ie: for glass and clear(transparent)plastics,; also I want to buy lenses, but i want to custom them via their diameters and focal points(low power lasers) , any ideas there?

 

[ronsimpson]

Custom=money
If there is any way you can use off the shelf, me to, everyone is using it, lenses the price will be better.
I have friends that use 3-D printing to make their plastic cases.
I get a ready made case and mill out holes.

 

[Pommie]

In Eagle run a design rules check on the board - it's near the bottom of the toolbar and shows DRC when you hover over it. It will show you any errors and some manufacturers supply a DRC file so you know you are complying with their rules. You should also run an ERC (Electrical rules check) on the schematic.

Mike.

 

[Dr_Doggy]

ya I kno, i wonder who would make cheap laser lenses, i say cheap laser lenses since i dont really need high quality laser lenses that can handle the heat, but someone who will have convex and con-caves , as oppose to lenscrafters, can i get example?

Ideally i thought it would be cool to even print some cheap plastic ones, however i havnt seen transparent plastic at the printshop yet, and i picture complications with surface smoothness and resolution.


back to this pcb though, that was a little complicated/confusing getting the gerber files out, again i dont even want silk screen ,is this ok?, is anything missing? also at which point did i define dimensions, was that the purpose of the polygon squares>?