Hy everybody!
I want to build my own PCB for the Leach Amp, but I have a few questions.
The PCB is made with photo UV method and i finished the PCB including drilling but my true problem start here ....
After drilling what are the steps to protect the copper traces ?
Some people say PLASTIK 70 other say FLUX SK 10 but I heard
that FLUX must be removed at the end ... ? I'm very confused
Some datasheets for these two sprays .. PLS
I go crazy because I don't know how to continue ...
Please tell me a solution step by step
I want to build my own PCB for the Leach Amp, but I have a few questions.
The PCB is made with photo UV method and i finished the PCB including drilling but my true problem start here ....
After drilling what are the steps to protect the copper traces ?
Some people say PLASTIK 70 other say FLUX SK 10 but I heard
that FLUX must be removed at the end ... ? I'm very confused
Some datasheets for these two sprays .. PLS
I go crazy because I don't know how to continue ...
Please tell me a solution step by step
And when your'e done with soldering, you can clean the hole pcb, with a glasslike brush (ask a dealer) - and some electronick cleaner, and give it flux again, for keeping the pcb nice and clean - the idea with the flux, is to make better soldering, and protect the pcb. You have to clean the hole pcb, when your'e done soldering, because it will look like sh.. 
then... when you read the leach-amp instruction's he is also mentioning it here!
good luck
then... when you read the leach-amp instruction's he is also mentioning it here!good luck
As a crude solution, if you used positive PCB with the UV sensitive layer built-in, you can keep that layer as a cheap and simple copper protection instead of cleaning it after etching
The strength and solderability of this layer may vary a lot between manufacturers, but for the material I use it works fine, it protects copper for years and it doesn't affect soldering at all since hot solder removes it very easily
Also, if you clean this layer too soon, days or even hours before soldering, copper may get dirty and oxidized enough to make soldering a pain
The board on the left was etched more then two years ago. The board on the right was etched a week ago
The strength and solderability of this layer may vary a lot between manufacturers, but for the material I use it works fine, it protects copper for years and it doesn't affect soldering at all since hot solder removes it very easily
Also, if you clean this layer too soon, days or even hours before soldering, copper may get dirty and oxidized enough to make soldering a pain
The board on the left was etched more then two years ago. The board on the right was etched a week ago
An externally hosted image should be here but it was not working when we last tested it.
I also intend to do a double side board for a vu-meter and to spray it with PLASTICK 70 RED varnish over both sides before soldering, because if I spray after soldering, copper traces under IC socket remain vulnerable at moisture, dust, etc
Also I want a more profi PCB ...
How it looks a pcb coated with PLASTICK 70 RED varnish ?
Also I want a more profi PCB ...
How it looks a pcb coated with PLASTICK 70 RED varnish ?
I get acceptable results by printing the masks in paper and then doing two photocopies on acetate transparencies. Then I use both photocopies supperposed, taking care to make them match and to place the toner sides facing down [closer to the PCB]
I use a heavy piece of glass to force the sheets to make good contact with the PCB
Two layers of toner are much more efficient than one at stopping UV light, so the UV sensitive layer doesn't get sensitized and weakened where it should'nt and thus etching time and concentrations are not so critical
It would be better to print the masks directly on acetate with a laser printer but I don't have access to one
I use a heavy piece of glass to force the sheets to make good contact with the PCB
Two layers of toner are much more efficient than one at stopping UV light, so the UV sensitive layer doesn't get sensitized and weakened where it should'nt and thus etching time and concentrations are not so critical
It would be better to print the masks directly on acetate with a laser printer but I don't have access to one
An externally hosted image should be here but it was not working when we last tested it.
I vote for leaving the photoresist on the board. It's easy to solder through (unless you coated it yourself and used too much). I wouldn't worry about the traces under the ICs, although you could always spray a generous amount of conformal coating and let it run under the chips. I've done the "coat everything with solder" thing in the past, but it doesn't look as smooth as factory, and it requires an uncomfortable amount of heat to tin big areas, enough that I see signs of delamination.
I've used the electroless tin coating. It can look nice if the copper is very smooth to begin with, and if the tin coating is buffed afterwards (scrap piece of blue jeans worked for me). However, the tin oxidizes too, so it still needs protection.
The tool I use for cleaning the pads was called a "Rust Eraser" pen, found in the body repair section of an auto parts store. (that must be the same "glasslike brush" that lykkedk uses)
As for printing artwork: laser printers (and photocopiers) aren't that good; they just fundamentally seem to have a tough time doing wide black areas. This is one place where inkjets are superior. I've had good results using inkjet transparency film, stacking two copies to improve the density. Since the transparency film isn't cheap, it makes sense to print several copies on a single sheet, and if possible use the sheet more than once (print near the bottom).
I just discovered Irfanview image viewing software. http://www.irfanview.com/ I was having a hard time getting some artwork to print to scale, but Irfanview let me specify the dpi and print it exactly. Irfanview can also join images to make panoramas; I used that feature to print multiple images side by side (copy the image to several differently-named files first).
I've used the electroless tin coating. It can look nice if the copper is very smooth to begin with, and if the tin coating is buffed afterwards (scrap piece of blue jeans worked for me). However, the tin oxidizes too, so it still needs protection.
The tool I use for cleaning the pads was called a "Rust Eraser" pen, found in the body repair section of an auto parts store. (that must be the same "glasslike brush" that lykkedk uses)
As for printing artwork: laser printers (and photocopiers) aren't that good; they just fundamentally seem to have a tough time doing wide black areas. This is one place where inkjets are superior. I've had good results using inkjet transparency film, stacking two copies to improve the density. Since the transparency film isn't cheap, it makes sense to print several copies on a single sheet, and if possible use the sheet more than once (print near the bottom).
I just discovered Irfanview image viewing software. http://www.irfanview.com/ I was having a hard time getting some artwork to print to scale, but Irfanview let me specify the dpi and print it exactly. Irfanview can also join images to make panoramas; I used that feature to print multiple images side by side (copy the image to several differently-named files first).
If you want to use laserjet or copiers to make your board get this stuff: Press-n-Peel Blue Transfer Film
at
http://techniks.com/
It actually works. I've produced boards with 1mm traces successfully.
Prosit
at
http://techniks.com/
It actually works. I've produced boards with 1mm traces successfully.
Prosit
I was having a very difficult time getting a clear film to work in a ink jet printer. The ink kept smearing. I was using a HP film. I was using a Canon and a Brother printer. I started making some phone calls and was told the ink is different between the Hp and other brands. That one is a water based ink and the other is a pigment based ink. I have no idea what that means.
Anyways, I tried the film in a HP inkjet and the artwork turned out great! Nice solid blacks with good density.
Anyways, I tried the film in a HP inkjet and the artwork turned out great! Nice solid blacks with good density.
Hi together!
To produce a PCB is easy. I always print out the artwork on a transparency. I do two printouts and glue it together. After developing the PCB with a sodium hydroxide solution, I remove the restiste with acetone. After drillung and cutting I use SK10 "Lötlack" from Kontakt-Chemie. That's all.
On my homepage you can see pictures. Although it is written in german, you can see the whole procedure.
The address is:
http://homepage.univie.ac.at/Wolfgang.Postl/pcb1.htm
Wopo
To produce a PCB is easy. I always print out the artwork on a transparency. I do two printouts and glue it together. After developing the PCB with a sodium hydroxide solution, I remove the restiste with acetone. After drillung and cutting I use SK10 "Lötlack" from Kontakt-Chemie. That's all.
On my homepage you can see pictures. Although it is written in german, you can see the whole procedure.
The address is:
http://homepage.univie.ac.at/Wolfgang.Postl/pcb1.htm
Wopo
After I finish the PCB I want to coat it with some color varnish to protect the copper traces but also I want to look a little bit profi and of course the protective film to be soldered through ...
What do u thinck ?
Such a varnish exist ? I saw something like that in some catalogs.
I think it is called PRF204 Green Elektrolak made by Taerosol. or PLASTIK 70 RED made by KONTAKT Chemie.
What do u thinck ?
Such a varnish exist ? I saw something like that in some catalogs.
I think it is called PRF204 Green Elektrolak made by Taerosol. or PLASTIK 70 RED made by KONTAKT Chemie.
Hi adrianbodor!
I have no experience with such substances. I think, when you want to have a professionell locking PCB, you have to order it from a company. Its more expensive, but looks good. Especially a double sided, plated through hole PCB is a good choice. The
PCB costs of a project are rather small. So you produce a running prototype and then you order the PCB from a company. It hink this is the best way to get a professional looking PCB.
Wopo
I have no experience with such substances. I think, when you want to have a professionell locking PCB, you have to order it from a company. Its more expensive, but looks good. Especially a double sided, plated through hole PCB is a good choice. The
PCB costs of a project are rather small. So you produce a running prototype and then you order the PCB from a company. It hink this is the best way to get a professional looking PCB.
Wopo
I don't try to solder through conformal coating, unless I'm in a real hurry: it looks messy (oxidized flux and bits of solder stick to it). I dip a Q-tip in isopropanol and twist that over the pad to clean it off. After replacing the component, use remove the flux the same way, and then apply some fresh conformal coating.
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