Pressure sensitive materials have an weak adhesive on them. You rub the image on to the printed circuit boards copper and it sticks. Another product called "Press Type" used to be used in advertising layouts and drafting rooms. But it really had the same adhesive, not as sticky as adhesive tape - but it is there.
The problem is that the longer you store the material, the worse its performance. I have some here that is 5 years old and I suspect it was already many years on the shelf when I bought it. It doesn't stick very well.
I just figure it is a complete waste of money as almost no one is buying it any more. So it is unlikely to be fresh and sticky.
You can clean the copper with an abrasive cleaner (the kind you clean the sink or pots and pans with) or you can use a pad - like steel wool or the plastic kind.
But I still fear you will find out that you got 'stale' material and you will still get gaps and rough edges. If you are willing to repair and the wires are not extremely narrow, that's fine. But if you want tiny details, you will have to go to photo-sensitive process. I use pre-packaged boards (Kingsten brand) and a regular desk lamp for exposure. The results are excellent. I print with transparencies created in Eagle and on an HP Inkjet.
After exposure to light, I just wash the board with bleach and have an image ready to be etched. If I see mistakes, I can use a black marker to fill in gaps before I etch. (With the pressure sensitive material you never know until it is too late.)
I use Ferric Chloride to etch, but there are other options and quite a few of them if you go to an art supply. Artists etch copper plate for printing and have a lot of experience with creating recipes or formulas that control the process exactly the way they want. From what I understand, the Ferric Chloride works better when mixed with lemon juice. Or you can use a very fast, rough enchant - such as Hydrochloric acid. Nitric acid would be very extreme, too fast.
I couldn't possible be bothered with trying to laminate boards. I buy them. They are usually two sided. The cheap ones have a phenolic paper filler, the expensive ones have an epoxy filler. One can buy one-sided as well.
I already bought Ferric Chloride, so I will try with that first.
Regarding the photo-sensitive process, I found it a bit expensive A blank board cost at leat $10 for 4"x6". Add the transparent sheets for the printing, the etchant, the revelator, etc. And you have something close to $15 or $20.
For $30 you have a very nice double side and pro PCB done online with 5 mils traces instead of home made 10.
And let's imagine you miss your board, you just spent up to $40....
With the laminator process, I need 2 sheets of gloss paper (0.5$), a board (4$ for a 12"x24"... No comments), and some etchant and that's all. Also, instead of blank gloss paper, you can take magasines gloss paper for free! So at the end, it's less than half the price. You can have your 4"x6" board for less than 1$!
I would love to use the photo-sensitive process by laminator myself a photo-sensitive sheet on top of my copper board, but I was not able to find such product so far. I think this process can be more precise than the laminator one for double-side boards.
Here is the spiral test I did with 12 mils picture.
I have printed it on a Lexmark E210, putted it 10 times into a laminator, soaked it into Windex+Soap+Water for 30 minutes, scrubbed the paper, and then edged it into Ferric Chlorid.
Honnestly? I'm VERY happy with the result!!! I verified it and the values are correct.
It's VERY easy to print it from gEDA, very easy to laminate, very easy to clean, and borring to etched, but that's mandatory
I also tried a 2-side one but I'm not sure they are aligned. I will etched it tonight. Also, I bought very copper board. Half of a regular one. I will try to print each side of my shema on a specific board, and glue them together. At the end, I think it will still be thin enought to solder through.
So more to come. I will post the pictures of the 2 double-side board when they will be done.
Double side with one board is not a total success.
Here are some pictures.
The etching was not as good as expected because the pipe for the bubles detached from the bottom, so between some tracks there was still some copper. Anyway, this is not related to the double side mode.
Let's look at the pictures.
From one corner of the board, I'm pretty good. Aligned from both sides. But on the other corner, it's a bit shifted. It's ok, I can still deal with that for this specific schema, but that can be an issue.
So I don't think it's possible to do a double-side board that way. Maybe with some methods to align the sides it will be doable, but my next try will be with 2 thin board laminated together.
I stopped useing Ferric Chloride many years ago .
I use ammonium persulfate from MG chem .
A) it wont stain bathroom ( mom almost killed me for ruining the corian when I was 10). its not as reactive slower ..
C) you can see in it . so its easy to see when a board is done .
D) comes as a powder .
but it will eat sharpie ink so use a real resist marker or " marks a lot brand" ( ya know the ones that will make you gag from 8 feet away ) or toner transfer to mark
There is a lot of good information throughout this thread and a really nice record of your progress. Your results look promising, so definitely keep moving forward.
I believe the 10mil traces are pitting because of the effectiveness of the toner transfer to the copper. Loopy already mentioned cleaning the copper with steel wool and I would second that. After cleaning with the steel wool, clean the surface of the copper with alcohol to remove any residue that may have been left by the steel wool. Also, when using the steel wool, use very light strokes and patience. Steel wool can remove the copper easily with force and can also leave grooves which will affect the transfer. Light, smooth strokes will give you a clean flat surface.
No one touched your "tinning" question so here's an answer. Tinning refers to applying a thin layer solder to the copper to protect the copper surface from oxidation and make component soldering easier. In PCB manufacturing, fabs that will have a tin/lead finish go through a HASL process, Hot Air Solder Leveling. The entire fab is dipped into a bath of molten solder and as the fab is lifted out heated air knives blow high pressure air across the fab to remove excess solder leaving a thin layer of solder across the pads. The "knife" consists of two bars of metal with facing cavities creating a plenum channel that feeds into a thin linear opening at one side to create a "blade" of air when high pressure air fed into the plenum entry. Here's a diagram of a standard air knife.
There is a lot of good information throughout this thread and a really nice record of your progress. Your results look promising, so definitely keep moving forward.
Thanks.
The secret is: Clean, clean, clean and then, clean The spiral board, I cleaned it 3 times with Vim. Clean it as long as the Vim get black/dark. And the result was perfect.
Regarding the second board, I tried to go faster, and got a bad result. Also, the space between the tracks is 10 mils when it's 12 mils on the spiral. So maybe I should stay with 12 mils.
Also, the laminator is helping a lot. I used the iron first, but it was not evenly pressed. Now, it's barely perfect.
I make my own SMT single sided boards, I find doublesided works for big tracks, but when you are trying to do very fine detail I seem to always fail on the alignment.
I design my board in free program, print it to a bitmap file (extra driver from Source Fire), flip it in MS Paint, then Print it on Press-n-Peel Blue (from a company called Techniks in NJ). Then iron it onto clean copper with a tea towel between the iron and the Press-n-Peel on the copper clad. Then soak it in water, peel it off. Then etch it with ammonium persulfate (it's clear, so you can see how the etch is going), it works best around 70C so I place it in a double pan with boling water on the outside. Unfortunatly it's very time consuming, it's ok for one off designs, but I wouldn't use it for production quality - I'd get them made up by a board house.
I've been able to etch QFP Props with FT232RL USB chips without too many issues. Seeing them is an issue.
I looked at the Press-n-Peel but found it to expensive...
So! I did my test for the double-side board and.... It's awesome! It's working A1!
Here are some pictures, and how I did.
On the last picture, where you can see the spagheti PPDB, the display is showing 3. Not sure if it's visible on the picture. Anyway, it's working fine!
The steps:
1) Find singleside board very thin.
2) Print the schema on a gloss paper.
3) Cut the board a bit larger than the schema.
4) Clean the boards with Vim about 4 times each.
5) Clean with acetone and don't touch the surface anymore.
6) Laminate the schema at least 10 times!!!
7) Put some Ivory on the paper. Let it penetrate for 5 minutes.
8) Spray some Windex on it. Let it penetrate for 2 minutes.
9) Put boiling water on it. Let it penetrate for 2 minutes.
10) Peel the paper.
Here, if you did it weel, you should have the paper perfectly pilled. No need to scrub with this method. And the tracks should be transfered to the board.
Proceed with the etching.
Drill 4 holes on the 2 boards. The same holes for the same components. You will use those holes to align your boards. Put some wires on those holes to help with the alignement. Put some contact glue between the 2 board, and press them hardly together for a long time (I did it for 4h. Depend on your glue).
Then drill all the holes, and solder
For the drilling, be carreful. If you place your board on a soft material, you might damage the copper on the oposite side. So place it on solid material like wood.
Also, be carreful with the schema you print. Some component are impossible to sold on the component side of the board...
I'm very happy with the result. That will give my Propeller based experiences another dimension! It's the first time I'm doing a PCB, and it's a woking-double-side one!
Just ask if you have any question
JM
PS: I know, I know, I totally suck with a soldering iron
VIM is a very fine, slightly abrasive powdered cleanser used mostly for scrubbing sinks and other enamelled or porcelain surfaces.
Ivory is a brand of plain liquid soap with no colorants and sometimes no perfumes as well. It also comes as a bar soap, but I don't think that's what's being referred to.
So if you take:
- A Bath Tub Cleaner
- A Dishes Liquid Soap
- A glass cleaner
Then you might be correct.
I will redo a 2nd board like this one (I need 3 digits) and will try to make some videos to show how easy it should be to remove the paper from the board.
I have always had good luck with toner transfer. I don't use a very complicated process.
1) Laser print reverse image on photo paper
2) Shine board with steel wool
3) Iron image on to board with regular clothes iron (cotton setting)
4) Soak board, peel, gently rub with fingers to remove paper
5) Etch with Ferric chroride
6) Drill
works incredible, just drill a few allignment holes if you want to make it double sided.
Comments
The problem is that the longer you store the material, the worse its performance. I have some here that is 5 years old and I suspect it was already many years on the shelf when I bought it. It doesn't stick very well.
I just figure it is a complete waste of money as almost no one is buying it any more. So it is unlikely to be fresh and sticky.
You can clean the copper with an abrasive cleaner (the kind you clean the sink or pots and pans with) or you can use a pad - like steel wool or the plastic kind.
But I still fear you will find out that you got 'stale' material and you will still get gaps and rough edges. If you are willing to repair and the wires are not extremely narrow, that's fine. But if you want tiny details, you will have to go to photo-sensitive process. I use pre-packaged boards (Kingsten brand) and a regular desk lamp for exposure. The results are excellent. I print with transparencies created in Eagle and on an HP Inkjet.
After exposure to light, I just wash the board with bleach and have an image ready to be etched. If I see mistakes, I can use a black marker to fill in gaps before I etch. (With the pressure sensitive material you never know until it is too late.)
I use Ferric Chloride to etch, but there are other options and quite a few of them if you go to an art supply. Artists etch copper plate for printing and have a lot of experience with creating recipes or formulas that control the process exactly the way they want. From what I understand, the Ferric Chloride works better when mixed with lemon juice. Or you can use a very fast, rough enchant - such as Hydrochloric acid. Nitric acid would be very extreme, too fast.
I couldn't possible be bothered with trying to laminate boards. I buy them. They are usually two sided. The cheap ones have a phenolic paper filler, the expensive ones have an epoxy filler. One can buy one-sided as well.
Regarding the photo-sensitive process, I found it a bit expensive
For $30 you have a very nice double side and pro PCB done online with 5 mils traces instead of home made 10.
And let's imagine you miss your board, you just spent up to $40....
With the laminator process, I need 2 sheets of gloss paper (0.5$), a board (4$ for a 12"x24"... No comments), and some etchant and that's all. Also, instead of blank gloss paper, you can take magasines gloss paper for free! So at the end, it's less than half the price. You can have your 4"x6" board for less than 1$!
I would love to use the photo-sensitive process by laminator myself a photo-sensitive sheet on top of my copper board, but I was not able to find such product so far. I think this process can be more precise than the laminator one for double-side boards.
JM
Time to show the results
Here is the spiral test I did with 12 mils picture.
I have printed it on a Lexmark E210, putted it 10 times into a laminator, soaked it into Windex+Soap+Water for 30 minutes, scrubbed the paper, and then edged it into Ferric Chlorid.
Honnestly? I'm VERY happy with the result!!! I verified it and the values are correct.
It's VERY easy to print it from gEDA, very easy to laminate, very easy to clean, and borring to etched, but that's mandatory
I also tried a 2-side one but I'm not sure they are aligned. I will etched it tonight. Also, I bought very copper board. Half of a regular one. I will try to print each side of my shema on a specific board, and glue them together. At the end, I think it will still be thin enought to solder through.
So more to come. I will post the pictures of the 2 double-side board when they will be done.
JM
Double side with one board is not a total success.
Here are some pictures.
The etching was not as good as expected because the pipe for the bubles detached from the bottom, so between some tracks there was still some copper. Anyway, this is not related to the double side mode.
Let's look at the pictures.
From one corner of the board, I'm pretty good. Aligned from both sides. But on the other corner, it's a bit shifted. It's ok, I can still deal with that for this specific schema, but that can be an issue.
So I don't think it's possible to do a double-side board that way. Maybe with some methods to align the sides it will be doable, but my next try will be with 2 thin board laminated together.
JM
I use ammonium persulfate from MG chem .
A) it wont stain bathroom ( mom almost killed me for ruining the corian when I was 10).
C) you can see in it . so its easy to see when a board is done .
D) comes as a powder .
but it will eat sharpie ink so use a real resist marker or " marks a lot brand" ( ya know the ones that will make you gag from 8 feet away ) or toner transfer to mark
I believe the 10mil traces are pitting because of the effectiveness of the toner transfer to the copper. Loopy already mentioned cleaning the copper with steel wool and I would second that. After cleaning with the steel wool, clean the surface of the copper with alcohol to remove any residue that may have been left by the steel wool. Also, when using the steel wool, use very light strokes and patience. Steel wool can remove the copper easily with force and can also leave grooves which will affect the transfer. Light, smooth strokes will give you a clean flat surface.
No one touched your "tinning" question so here's an answer. Tinning refers to applying a thin layer solder to the copper to protect the copper surface from oxidation and make component soldering easier. In PCB manufacturing, fabs that will have a tin/lead finish go through a HASL process, Hot Air Solder Leveling. The entire fab is dipped into a bath of molten solder and as the fab is lifted out heated air knives blow high pressure air across the fab to remove excess solder leaving a thin layer of solder across the pads. The "knife" consists of two bars of metal with facing cavities creating a plenum channel that feeds into a thin linear opening at one side to create a "blade" of air when high pressure air fed into the plenum entry. Here's a diagram of a standard air knife.
I was not able to find that locally here
Thanks.
The secret is: Clean, clean, clean and then, clean
Regarding the second board, I tried to go faster, and got a bad result. Also, the space between the tracks is 10 mils when it's 12 mils on the spiral. So maybe I should stay with 12 mils.
Also, the laminator is helping a lot. I used the iron first, but it was not evenly pressed. Now, it's barely perfect.
Super, thanks for the details.
I saw few videos on Youtube where people are doing tinning at home. I'm wondering what product they are using to do that.
Tomorrow I will post the pictures of the 2nd attempt for the homemade laminated double-side board
JM
I design my board in free program, print it to a bitmap file (extra driver from Source Fire), flip it in MS Paint, then Print it on Press-n-Peel Blue (from a company called Techniks in NJ). Then iron it onto clean copper with a tea towel between the iron and the Press-n-Peel on the copper clad. Then soak it in water, peel it off. Then etch it with ammonium persulfate (it's clear, so you can see how the etch is going), it works best around 70C so I place it in a double pan with boling water on the outside. Unfortunatly it's very time consuming, it's ok for one off designs, but I wouldn't use it for production quality - I'd get them made up by a board house.
I've been able to etch QFP Props with FT232RL USB chips without too many issues. Seeing them is an issue.
I looked at the Press-n-Peel but found it to expensive...
So! I did my test for the double-side board and.... It's awesome! It's working A1!
Here are some pictures, and how I did.
On the last picture, where you can see the spagheti PPDB, the display is showing 3. Not sure if it's visible on the picture. Anyway, it's working fine!
The steps:
1) Find singleside board very thin.
2) Print the schema on a gloss paper.
3) Cut the board a bit larger than the schema.
4) Clean the boards with Vim about 4 times each.
5) Clean with acetone and don't touch the surface anymore.
6) Laminate the schema at least 10 times!!!
7) Put some Ivory on the paper. Let it penetrate for 5 minutes.
8) Spray some Windex on it. Let it penetrate for 2 minutes.
9) Put boiling water on it. Let it penetrate for 2 minutes.
10) Peel the paper.
Here, if you did it weel, you should have the paper perfectly pilled. No need to scrub with this method. And the tracks should be transfered to the board.
Proceed with the etching.
Drill 4 holes on the 2 boards. The same holes for the same components. You will use those holes to align your boards. Put some wires on those holes to help with the alignement. Put some contact glue between the 2 board, and press them hardly together for a long time (I did it for 4h. Depend on your glue).
Then drill all the holes, and solder
For the drilling, be carreful. If you place your board on a soft material, you might damage the copper on the oposite side. So place it on solid material like wood.
Also, be carreful with the schema you print. Some component are impossible to sold on the component side of the board...
I'm very happy with the result. That will give my Propeller based experiences another dimension! It's the first time I'm doing a PCB, and it's a woking-double-side one!
Just ask if you have any question
JM
PS: I know, I know, I totally suck with a soldering iron
I'll have to try straight toner transfer.
What is Vim?
What is Ivory?
They sounds like product names, what are their main ingredient?
Again - thank you for sharing.
Ivory is a brand of plain liquid soap with no colorants and sometimes no perfumes as well. It also comes as a bar soap, but I don't think that's what's being referred to.
Honnestly? I impressed myself
Vim in north america is like Cif is Europe. I don't know what's inside.
Look at:
http://www.vimcleaners.co.uk/
http://www.unilever.com/brands/hygieneandwelbeing/aroundthehouse/articles/cleansolutionsfromvim.aspx
Ivory is the soap used for dishes handwashing.
Here: http://www.ivory.com/yourivoryproducts_ultraivory.htm
But I think you can take any other liquid soap.
And Windex is a glass cleaner.
http://www.windex.com/products/
So if you take:
- A Bath Tub Cleaner
- A Dishes Liquid Soap
- A glass cleaner
Then you might be correct.
I will redo a 2nd board like this one (I need 3 digits) and will try to make some videos to show how easy it should be to remove the paper from the board.
JM
1) Laser print reverse image on photo paper
2) Shine board with steel wool
3) Iron image on to board with regular clothes iron (cotton setting)
4) Soak board, peel, gently rub with fingers to remove paper
5) Etch with Ferric chroride
6) Drill
works incredible, just drill a few allignment holes if you want to make it double sided.
Jim