I am about to create my first PCB in a very long time. So I guess I am really a newbie at PCBs.

I have included the PCB layout below. It is not finished. I still need to add the control / multimeter PCB. When it is complete I will post the schematic and PCB layout for peer review when it is complete.

If someone want to make initial comments on my design then that is fine but the purpose of this post is to determine the best method of doing a DIY PCB.

I am posting the layout so a proper assessment can be made. Both boards will be single sided.

First I have no PCB supplies. I am starting fresh. I do not have access to a laserjet printer but would make use of a printing service like Kinkos, if that is what is recommended.

I am also willing to purchase transparencies for my inkjet, if that is the recommendation.

So considering I am a newbie at this and will more than likely be making my own PCBs in the future. What is the best method for me right now?

I know some methods use a sharpie. Maybe a little difficult considering my layout?

There is the transfer method .

There is a transparency exposure method.

I am sure there are more.


What method is best for me? Considering my experience and PCB layout?

 

I've been using a laserjet printer and magazine-type paper with a 300°F clothes iron to transfer the toner to copper boards with decent results. I've been using the shiny supermarket ads out of the newspaper. The existing ink doesn't transfer; only the laser toner does.

You can get a laser printer for around $50. That'll save you money in trips to the copy place. You're bound to make a mess out of the first few boards. Don't let that get you down though.

It's hard to comment on your layout, since no components are shown.

 

Thanks. Did not really want a critique right now on the layout. Just wanted to show it so folks knew what I was working with.


Your point on just buying a laserjet is a good one. Plus I doubt Kinkos would print on a magazine. They will want to sell you expensive transparencies.

I guess the nice thing about transparencies is it makes lining up the image a bit easier.

The problem with a used LJ is that it will probably be a parallel port. My PC does not have one.

 

I bought a used LaserJet 4050TN on an auction site for $50. It has an Ethernet interface built in. The thing sounds like a very quiet miniature jet engine when it's winding up to print. It's large, but it's very fast - it's really an office-type printer. I've probably printed 3,000 pages and I'm still on the original cartridge. You can't do that with an ink printer. Cost/page for a laserprinter is very low.

 

I use the transparency method (photo method) myself with Injectorall (DigiKey) pre-sensitized boards. I have had poor luck with the toner transfer (TT) method. Nevertheless, I suggest that you might want to try that method first.

Rationale:
1) TT has lower start up expense. You can get the laser printing done at any commercial shop, school, library, etc. for almost nothing. You can use a home iron for heating. So, all you really need to get is a small piece of copper clad PCB, clean it, and try it.
2) For the photo method, I strongly recommend buying pre-sensitized boards. Making your own boards is a hurdle few can master, even if you can find the spray or dip solutions. You also need a UVA source. Developer can be made at home from NaOH or KOH, if you have an accurate balance/scale. If you do not, then you will have to buy it. You will also need two pieces (about 4X6") of single pane window glass and some weak clips. Excluding the cost of the pre-sensitized boards, you will probably have at least $30 in equipment and supplies.
3) Any method can fail, but based on many reports, initial success is probably more likely with the TT method. Every few years or so, after reading all of the rave reports, I try it again. I even bought a bunch of stuff from a commercial house and a laminator. I get usable boards, but I just don't like the appearance, particularly of large ground planes. So, I go back to the photo method. On the other hand, with the photo method, you are likely to have some complete failures initially until you get your conditions set. Those failures can be expensive considering the cost of the pre-sensitized boards.

John

 

I can see a problem in your solder pads. They should be larger. Small solder pads in a homemade PCB do have a tendency to fall off after some rework. And this can be really annoying.

 

I have bought laser printers for $10. They are out there if you look.

 

Laser printers in the last 6 years should support USB too.

 

I have bought laser printers for $10. They are out there if you look.

One that works? Or did you have to fix it?


Where? Craigslist? Ebay?


I would be a little hesitant to buy from Ebay. For one, shipping would be expensive?

 

I use the transparency method (photo method) myself with Injectorall (DigiKey) pre-sensitized boards. I have had poor luck with the toner transfer (TT) method. Nevertheless, I suggest that you might want to try that method first.

Rationale:
1) TT has lower start up expense. You can get the laser printing done at any commercial shop, school, library, etc. for almost nothing. You can use a home iron for heating. So, all you really need to get is a small piece of copper clad PCB, clean it, and try it.
2) For the photo method, I strongly recommend buying pre-sensitized boards. Making your own boards is a hurdle few can master, even if you can find the spray or dip solutions. You also need a UVA source. Developer can be made at home from NaOH or KOH, if you have an accurate balance/scale. If you do not, then you will have to buy it. You will also need two pieces (about 4X6") of single pane window glass and some weak clips. Excluding the cost of the pre-sensitized boards, you will probably have at least $30 in equipment and supplies.
3) Any method can fail, but based on many reports, initial success is probably more likely with the TT method. Every few years or so, after reading all of the rave reports, I try it again. I even bought a bunch of stuff from a commercial house and a laminator. I get usable boards, but I just don't like the appearance, particularly of large ground planes. So, I go back to the photo method. On the other hand, with the photo method, you are likely to have some complete failures initially until you get your conditions set. Those failures can be expensive considering the cost of the pre-sensitized boards.

John

Thanks for the advice. Would a commercial outfit print to a magazine page? I have read that there are other types of paper that can be used?


I guess another problem with doing the transfer method with commercial printing that if you mess it up then it is back to the store again.

It cost $2 a page to print a transparency. Not sure what they would charge for a transfer paper, if one exists.

 

I can see a problem in your solder pads. They should be larger. Small solder pads in a homemade PCB do have a tendency to fall off after some rework. And this can be really annoying.

I am using ExpressPCB. They allow you to change the size but require that you create a custom component. So, now I need to redo everything!
I wish they had a way to change existing components.


What size would you recommend?

 

Question on the transfer method. I do print a mirror image correct? Looks like ExpressPCB already does this. At least that is one good thing.

 

Found it. It is super glossy photo paper that some people use. Would this achieve better results than magazine paper?

 

If you are printing the traces/pads/vias for the bottom layer, you print it just like it is.
If you are printing the traces/pads/vias for the top layer, you mirror-image it.
If you are printing the text/silkscreen that goes on the top layer to iron it on, you mirror it.

They seemed to have changed the glossy photo paper I'd been using; now there is a few layers of plastic in the paper that is almost impossible to remove without goofing up the toner transfer. It's also considerably more thick than magazine paper, so it takes far longer to soak/scrub it off. Besides that, glossy photo paper is like $20 for 50 sheets, and you get lots of magazine paper in any Sunday newspaper.

 

I mentioned the glossy photo paper for two reasons.

1. Thought maybe it would get better results. From the sounds of it, I will actually get worse results and have it cost a lot more too.

2. The most important reason. I realized I have a friend that has an LJ. She uses it for her business. She might be reluctant to put magazine pages through it. Though she did make me a bumper sticker once. I saw one at Pirates Pub in Virgin Gorda. "Have you flogged your crew today"? I loved it so much she made a bumper sticker or me with the same phrase. (we are both sailors and captains),


When you say "just as it is". Do you mean the way ExpressPCB prints it? Which is really a mirror image.

The stuff in the newspaper. The shiny ads? Any tips on the best characteristics of the ad? Light color? Or does it not really matter? I'm guessing the one really important requirement that the ad must have something to do with electronics??


Any tips on a good pad size for a newbie?

 

I mentioned the glossy photo paper for two reasons.

1. Thought maybe it would get better results. From the sounds of it, I will actually get worse results and have it cost a lot more too.

Feel free to experiment all you like. Your mileage may vary.

However, I found the magazine-type paper to give much better results than I'd gotten using the new glossy photo papers, and was a heck of a lot easier to soak/scrub off.

Make sure you prep the board really well. Scotchbrite pads work OK. I've been "cheating" and using a fine rotary Scotchbrite-type pad in my drill press; makes nice fine circular scratches in the copper without lots of elbow grease. Use clean paper towel and acetone to remove any residual copper oxide and contamination before you iron on the transfer with a 300° clothes iron. Don't use steam; that cools down the iron. You don't want to use a blazing hot iron either; because that will melt the toner and you're more likely to have it smear. You just want it to be in a "plastic" state. I use a digital thermometer to check the iron temp; I bought it in the kitchen goods section at the grocery for a few bucks.

2. The most important reason. I realized I have a friend that has an LJ. She uses it for her business. She might be reluctant to put magazine pages through it.

It won't hurt the printer, but will tend to jam if it's been folded before, or the edges are rolled up.

When you say "just as it is". Do you mean the way ExpressPCB prints it? Which is really a mirror image.

Just select whether you want to print the top copper layer or bottom copper layer. It'll come out fine for transfer.

You'd need to mirror-image the silkscreen layer if you wanted to iron on the text though.

The stuff in the newspaper. The shiny ads? Any tips on the best characteristics of the ad? Light color? Or does it not really matter?

It doesn't really matter. The ink from the ads doesn't transfer. I trim off at least two edges before ironing it on; that way it's easy to line up with the edges of the circuit board.

Any tips on a good pad size for a newbie?

Large pads. I also suggest that you don't run traces through pads if you can avoid it. If you "lift" a pad by overheating it, and a trace was running through the pad, you'll have more work to repair the damage. Run traces near the pads, and then have a separate trace link directly to the pad.

 

What is the best etchant to use? Considering I am snowed in and doing anything outside will be difficult. )

I have a basement but no garage.

 

I am using ExpressPCB. They allow you to change the size but require that you create a custom component. So, now I need to redo everything!
I wish they had a way to change existing components.
What size would you recommend?

Hard to say, but do some experimenting. I also like to use oval pads, as they hanlde drilling and rework better.

 

I use staples brand photo paper, it has worked the best out of all the different ones I used when I used to use the toner transfer method, it is the Photo Basic Gloss (Item # 471861) it has 30 sheets in a package, cheaper than others too last time I bought some......

 

I am using ExpressPCB. They allow you to change the size but require that you create a custom component. So, now I need to redo everything!
I wish they had a way to change existing components.


What size would you recommend?

To edit an existing component in ExpressPCB :

1. Select the component you want to edit.
2. Click on the "Component" menu.
3. Select "Ungroup PCB Component".
4. Once you have done this, unselect the item, (by clicking somewhere else on the screen...)
5. double click the pad you want to edit, a window will pop up where you can change the size of the pad and drill hole.
6. make the changes you want......
7. once you are done editing, select the whole component again,
8. click on the component menu again
9. select "Group to make component"
10. then you can save the component under your favorite components....

You can make then any size you want, as long as you leave enough room between pads so you don't easily bridge the solder across 2 pads...