PCB making: Toner transfer method

[ashok]

2 parts hydrogen peroxide ( 10 % solution I think ) and 1 part (cleaning) HCL solution ( possibly 10 or 20% solution ). This is what I used and it works well but doesn't stay well after it is mixed. Be very careful as you will have HCL fumes that can corrode any metal parts nearby. Do it in a well ventilated room or in the open !

 

[sandstorm33]

2 parts hydrogen peroxide ( 10 % solution I think ) and 1 part (cleaning) HCL solution ( possibly 10 or 20% solution ). This is what I used and it works well but doesn't stay well after it is mixed. Be very careful as you will have HCL fumes that can corrode any metal parts nearby. Do it in a well ventilated room or in the open !

Many Thanks!!

 

[gtforme00]

The warmer the solution, the faster it works. Some heat is produced by the reaction, but if you preheat the chemicals by soaking the bottles in a warm water bath, the etching time will be reduced.

 

[zlast]

Etchant

The best part of the H2O2 + HCL combination is that after you use it the first time you are left with a green solution. If you bubble air through the solution while you etch, it reverses the chemical reaction plus speeds up etching, and you can reuse the solution indefinitely.

 

[AndrewT]

And I got A++ in high school chem!!!

I can remember Ac, Ag, Al, As, At, Au but not A++

 

[ashok]

If you bubble air through the solution while you etch, it reverses the chemical reaction plus speeds up etching, and you can reuse the solution indefinitely.

Ah....that's really interesting. Thanks for the info. Must try it out.
My last board ( 4x4 inches) etched in less than 5 minutes. All I did was rock the dish ( I did it in a flat dish ).
Ambient temperature is now 30 deg C!

WARNING.
For newbies : wash your hands ( and dishes) VERY well after you handle the acid . HCL can eat up a lot of things including the enamel of your teeth if you accidentally rub your mouth with a "dirty" hand ! So rinse everything well after using it .
If you see the fabric falling apart on your clothes after a while , you know where the HCL fumes went ! The fumes seem to be present only while mixing . After the two are combined I didn't see any visible fumes. The fumes look like whisps of thin smoke. DO NOT try and inhale it to see how it smells !!!!

If you bubble air through the mixture it should potentially cause some fumes to come out of the mixture and you should take all precautions as mentioned earlier.

 

[Dave]

Folks,

You can get PCBs made at very reasonable cost these days, I use
www.pcbcart.com

Considering the amount of time required to make your own boards to me it could never be worth the effort.

 

[Nordic]

Compared to the cost of home made boards... I have yet to see a "reasonable" factory.... Ok, its a lady dog when you need to drill hundreds of holes (PI prototypes ).

If you have an electronics component shop, just ask for some ferric chloride to etch with... liquid prefferably... should set you back $2.

I reused my first bucket (500gr) of FeCl grannules for over a year... just need some water, heat and stirring.. (I use a plastic fork from take-aways).
I find the bubbler idea crazy.... I don't want staining bubbles poppoing, thank you.

 

[tomchr]

Perfect paper for toner transfer

Folks,

I'm using an HP LaserJet 4 for toner transfer PCB making and I have identified a type of paper that works really, really well. HP Laser Glossy Brochure Paper (P/N: Q6611A). I got it at OfficeMax for about $20 for a 150-sheet pack.

I have tried various other papers including glossy photo papers (one sheet got stuck in my printer as the coating melted in the fuser!), magazine paper (the cover sheets of USA Hockey magazine work very well but the rest of the magazine is useless for PCB making), etc. The paper linked to above is the only one I've found that doesn't seem to wrinkle and shrink under the heat of the iron during the toner transfer process.

Just thought I'd share...

~Tom

 

[knairkuttan]

thanks

 

[edbarx]

The Toner Method Vastly Improved:
This method, which I watched on Youtube, does not use heat and pressure as a means of toner transfer from paper to copper laminate. This uses instead acetone. Acetone is a component is some nail polish removers.

The Method:

• Clean the PCB's copper laminate with a very fine sandpaper. Wipe off the dust using a clean cloth.
• Print the PCB tracks on a normal printer paper. Do not use special paper, there is no need for that.
• Place the printed paper on the PCB with the printed surface in contact with the copper laminate.
• Fix firmly using masking tape.
• Place the PCB laminate on a flat surface with the copper laminate facing upwards.
• Get a nail polish remover that contains acetone. Pour enough of it to dampen the printed paper. With the tip of a finger, massage the polish remover into the printed paper, but be very very careful not to break it or stretch it. Make sure it remains in contact with the copper laminate. Continue massaging until the tracks become clearly visible. Use some pressure but very carefully.
• Leave enough time until the acetone dries.
• Place the PCB with the paper still affixed into a container with water. Leave for enough time for the paper to soften.
• Use a small paiting brush, width ~1cm, to very very carefully remove the paper. This procedure is critical. Also make sure all paper is removed.
• When you are sure only the toner is left, etch the PCB.

Note:
I tried this method and found it is very good compared to using heat or correction fluid.