PCB, Toner transfer method

[Y2KEDDIE]

i’ve decided to try making some PC boards using the toner transfer process (using laser jet printer).

The process calls for using multiple passes through a laminators To transfer the image from paper to the copper. An alternative is to use a clothing iron.

Another thought is to use a hot press, the type used for transferring toner/silkscreen images to tee-shirts / sweatshirts. Has anyone tried this, what were your results?

I’m looking at a small. . 6”x 9”, ephotoinc EPH10BU, heat press from AMAZON.

thanks,

Eddie

 

[BobK]

The cheapest way is to use a clothes iron. But I have never been able to get reliable results with either the iron or with a modified laminator.

Bob

 

[kellys_eye]

Before the proliferation of 'next day' PCB manufacturers I used to make my own using the toner method. The good old laminator worked just fine - so does the iron but it takes a lot of effort to get right!
Nowadays, if I wanted a PCB I'd be using those next-day services as they are far cheaper than even making your own and certainly a lot less hassle, with better results etc (solder mask, component overlay).
Usually the only thing stopping 'everyone' using such services is the fact that you have to design the board using some software whereas a lot of home made PCBs are done from hand sketches but with some manufacturers offering those services via their own software packages it seems a 'crime' not to learn how to do it.

 

[Bluejets]

After doing this for quite a while with various hit and miss results, cracked on to a system which works every time for me.

I use the yellow toner transfer paper from Ebay, print on the correct side of course, clean copper clad board with steel wool and then isopropol alcohol on a toilet tissue.

Mark standard A4 sheet so one knows which end goes into the printer first and print a "demo". Cut and tape a piece of yellow paper about 1.5" larger on all sides to the demo. Feed back into the printer and after it's come through again, carefully untape the yellow paper.

Place this centrally on the clean board and fold the remaining yellow paper along the edges and back to the rear and tape together. Basically one ends up with the board inside an envelope.

Have a large masonite cutting board where I place a "larger than the board" piece of 1/4" thick balsa with a few layers of doubled-up toilet tissue. This is a base for the heating/ pressure part.

Place the board on top with the toner part of the envelope upper most and add another few layers of doubled-up toilet tissue.

Turn on the iron and set to around 75% max heat and allow the iron to cycle a couple of times.
I have the bench height arranged so I can place the iron on top and then apply pressure with all my weight and arms straight. Reason being one needs to hold it for around 2 minutes. Do NOT move the iron once placed over the board. After the 2 minutes time, remove and allow to cool naturally before peeling back the yellow paper remnants.

Movement of the iron, too much heat, too long a cook time all result in crappy blurred finish.
Never had any luck with modified laminators.

 

[Fish4Fun]

Hey Y2KEDDIE !

IMHO Toner Transfer is a PITA ... many, many people have managed to get decent results using this method .... the common denominator appears to be meticulous attention to detail following a relatively lengthy trial and error period. Perhaps the biggest problem is the large number of variables that are simply impossible to quantify ... things like printer type, toner type, printer fusion temperature, paper moisture content, toner moisture content, transfer temperature, and the list goes on and on ....

Even assuming the toner transfer process goes perfectly, the learning curve on etching & drilling can take several attempts to get right.

What are the alternatives? Obviously if the design is headed toward production then having the prototype PCBs made by a PCB mfg is truly the best option. If the PCB is a one-off DIY project it can be harder to justify the cost of paying for a professionally made PCB ... and with a one-off DIY project the out-of-pocket costs are paramount to the "hobby time wasted" on the project.

My answer is to "cut" prototype PCBs on a CNC router. With my current machine I can maintain 10mil traces with 10mil spacing which generally meets my needs ... but the process can be time consuming. For a simple PCB I typically create the primitives directly in a CAD/CAM program designed for creating gCode files ... more complex PCBs I create in Altium Designer then export the GERBER files and then import them into my CNC CAD/CAM software ... and then make requisite modifications to generate suitable gCode files ... For two sided PCBs I create two "single-sided" PCBs from 0.030" thick PCB material and simply glue them together ... it is easier for me than flipping a two sided PCB over and indexing it properly.

Other methods include:

Painting the copper with black paint and then using a CNC Laser to ablate the paint ... there is a lengthy thread on that method elsewhere in this forum.

Modifying a laser printer to direct print onto a PCB. I don't know that anyone has ever successfully achieved this method, but I have read many "starts" to said project. I have some flexible 0.007" thick PCB material that **in theory** will feed directly into my HP LaserJet ... but I have never tried it.

Modifying an inkjet printer to direct print resist to PCBs. There is a very detailed "how to" for a particular model inkjet printer floating around on the net, but the modifications are for a printer that hasn't been in production since the early 2000s ... I searched ebay and other sources for one of these printers for a very long time and never found one ...

The most promising technology I have read about involves "conductive inks". In theory almost any 3D printer with a specially designed print-head could "print" traces onto any suitable substrate ... with a 0.1mm nozzle the nominal trace width would be ~4mil which should translate safely to ~6mil trace + 6mil spacing ... The biggest problem with this technology right now is that the inks & print heads simply aren't readily available to hobbyist.

At the end of the day, making one PCB is expensive and time consuming no matter how you do it ... it is all about finding the method least offensive to you

Fish

 

[BobK]

You forgot pre-sensitized positive boards. These are made by printing the PCB layout onto a trasparecy, then using this with a light box to expose the board to UV. You then develop the board in dilute NaOH and it is left with the resist wherever copper should stay. Then etch as usual. I have had some luck with this process, but still have some problems.

Bob

 

[HellasTechn]

i’ve decided to try making some PC boards using the toner transfer process (using laser jet printer).
The process calls for using multiple passes through a laminators To transfer the image from paper to the copper. An alternative is to use a clothing iron.
Another thought is to use a hot press, the type used for transferring toner/silkscreen images to tee-shirts / sweatshirts. Has anyone tried this, what were your results?
I’m looking at a small. . 6”x 9”, ephotoinc EPH10BU, heat press from AMAZON.
thanks,
Eddie

Myself i always use the toner transfer method with a small 1000W travel iron for clothes and im printing on magazine semi glossy paper. The printer i use is a samsung m2026. the results are very good (including good quality ground plane).
Solder mask is a bit hard if you use the UV paint bit its very easy if you use dry film. I personally prefer to tin my boards and apply conformal coating, so i do not use soldermask.

ordering a PCB can be very easy and trouble free but if you take pleasure in building your own PCB's like i do then i recommend toner transfer.