problems with pcb ironing method

[little_carlos]

hello guys, im having a lot of troubles with the ironing method to transer a printed circuit to the pcb, its a medium complexity circuit, its giving me troubles, every time y try there are lines missing or other crap, ive done some other pcbs with the same method, but they lacked of complexity, they were very simply, any advices that you can give me in order to succed with this? i cant afford other methods like photo resistive because of money limits, so other methods are not possible
here i show you the pdf of the circuit : http://www.mediafire.com/view/ajpe8ft42w3nfue/small_plc.PDF

[tautech]

Here's a few links to threads with plenty of info and advice:
https://www.eevblog.com/forum/beginners/smallest-pitch-for-home-made-pcb-that-is-doable-for-experienced-guys/
https://www.eevblog.com/forum/beginners/what-paper-should-i-use-for-making-pcbs-using-the-toner-transfer-method/
https://www.eevblog.com/forum/projects/pcb-at-home-guide/
https://www.eevblog.com/forum/eda/sharing-my-personal-experience-with-homemade-pcbs-using-toner-transfer/

[nshin31302]

Hello,
I used to have problems making PCBs using the toner transfer method, in fact, I asked this same (similar) question on the eevblog forum. So first of all, are you using a Brother printer? This was the main problem I had. The toner in Brother Printers can't be used to make PCBs. Also, what type of paper are you using,what iron do you use at what setting, how long do you iron it for,etc. Also, what are the exact things that happen when you try making the pcb? . Please be more specific, and I'll be glad to help


Edit: Read my thread on this question and the answers to see if any are useful.
https://www.eevblog.com/forum/beginners/what-paper-should-i-use-for-making-pcbs-using-the-toner-transfer-method/msg646213/#msg646213
Also try this guy's video.

[kerrsmith]

You could also try using the method shown in another of ECProjects videos:



I use this method and it really works well.

[wasyoungonce]

I found changing to a modified laminator (thermostat changed to 170C to heat to a higher temperature) and taping the paper down to the PCB with Kapton tape, really improved my boards.  I do multiple passes thru the laminator. 
http://ultrakeet.com.au/write-ups/superFuserV2

[rolycat]

I've had good results using sheets of self-adhesive vinyl. The toner transfers really well, although you need to be careful with the temperature - I used an iron on a fairly cool setting (silk/synthetics). This is a small board which I produced recently while playing with Kicad:



It has an SSOP IC with a 0.65mm pin pitch and uses 0.25mm traces (10 mils for our American friends).

The circuit is courtesy of another forum regular - anyone recognize it?

[nshin31302]

Why do you say that? I think it is an urban myth and you are not helping the situation by repeating it again. I have a Brother laser printer (HL-2040) and it works fine. I looked at the MSDS for the toner and as far as the ingredients that are listed it appears very much the same as other brands. HP is one I recall. If you have found that the toner (what else could it be) is not suitable then the toner must be different. Mine wasn't.  It could be that more recent laser printers use toner that fuses at much higher temperatures but if the paper doesn't feel all that much hotter when it is ejected then I think it is unlikely. It would just mean the printer uses more energy to do a job previously done with less energy.

You may be right about newer printers using toner that fuses at much higher temperatures. For example, this instructable, http://www.instructables.com/id/Toner-transfer-no-soak-high-quality-double-sided/?ALLSTEPS states that a Dell 5100 cn laserjet also will not work for making PCBs. Also, I've read PCB guides that recommend not to get printer toner from distributors other than the company that made it for making PCBs because the toner could have a possibility not working. There are  probably countless other (laser) printers that will not work for making PCBs. I have a Brother HL-31700W printer ( got it last November) that I've tried using, with different types of paper, to make PCBs using the toner transfer method, but I've failed at all the attempts. After a bit of surfing the web, I've found several sites that state that Brother printers can't be used to make PCBs. Although the toner would sometimes transfer, there would be missing traces. So I tried with a different laser printer and on the first attempt, I was able to get a decent transfer. O0

[tautech]

I've had good results using sheets of self-adhesive vinyl. The toner transfers really well, although you need to be careful with the temperature - I used an iron on a fairly cool setting (silk/synthetics). This is a small board which I produced recently while playing with Kicad:



It has an SSOP IC with a 0.65mm pin pitch and uses 0.25mm traces (10 mils for our American friends).

The circuit is courtesy of another forum regular - anyone recognize it?

Pusle generator. Nice. 

Waveform, Risetime?

[janoc]

I've had good results using sheets of self-adhesive vinyl. The toner transfers really well, although you need to be careful with the temperature - I used an iron on a fairly cool setting (silk/synthetics).

I second the idea of using the vinyl. It works quite well, but be careful with both temperature and pressure - too hot and too strong pressure will likely melt the vinyl, stretch it and smear the toner to boot. Not good.

The key to toner transfer is a clean, degreased and scrubbed board, then heating it enough so that the toner actually melts, pressure isn't that important. Also some printers are better than others - e.g. my cheapo Samsung has problems with coverage in large areas, causing pitting and sometimes broken traces. The office LaserJet that we have at work produces much better results.

[wasyoungonce]

Some Brother B&W LASER printers do not have a waste toner bottle they return the unused toner back into the toner cartridge.   Thus the toner starts to become more difficult to fuse, thus they use a variable corona voltage that increases with toner age/use which improves toner fusing.   These Brothers are ideal for toner paper fusing PCBs.  I use refill toner in my HL2270DW and get great results.

[Votality]

Some Brother B&W LASER printers do not have a waste toner bottle they return the unused toner back into the toner cartridge.   Thus the toner starts to become more difficult to fuse, thus they use a variable corona voltage that increases with toner age/use which improves toner fusing.   These Brothers are ideal for toner paper fusing PCBs.  I use refill toner in my HL2270DW and get great results.

Do you just keep a small amount of toner in for each print and discard used toner?

I have a hl2040cn, but haven't tried it for pcb transfer yet

[Whales]

Brother MFC-7340 works for me.  It's basically a brother HL-2142 (same lower half, drum, toner) with a scanner ontop.

Best of all I can con/coerce it into using "empty" toner containers for a long time. 

[rolycat]

Waveform, Risetime?

~ 4 kHz square wave with measured rise time of ~ 1.3 ns (500 MHz scope).

[Psi]

Are you moving the iron around to applying pressure and heat over the entire area of the PCB?
The iron has hot/cold spots and usually dimples where there is no heat at all.

Also did you clean the copper really well before you started?

[CatalinaWOW]

When you say you are missing lines etc. I assume you are talking about toner on your un-etched PWB.  You can get a lot of clues about what is happening by carefully examining results.

1.  First, is the paper stuck to your board?  It should be.  If not you either didn't fuze the toner, or it didn't stick to your board.  If you have a low density circuit the paper may peel easily from the board, but I haven't had much success mechanically removing the paper.  Water soak and gentle abrasion if the fuzing process was successful.

2.  Are the traces that ARE there easy to remove?  If so your issue is adhesion and is more likely to be a cleaning/surface finish issue, but may indicate marginal fusing temperature.

3.  Use a strong magnifying glass or microscope to examine the traces which did transfer.  Look for clues about how the fuzing went.

4.  Try test runs fuzing a pattern from one paper to another.  While the thermal characteristics of the paper are very different from paper, if your heat source can't make this transfer you need something hotter, more time or something along those lines.

Everyone will have different tools available to diagnose the problems.  If you are using this method your tools are likely to be crude and or makeshift (since low budget is the most common reason for doing it), but that just means that you will have to use your head more extensively.

[sleemanj]

Why do you say that? I think it is an urban myth and you are not helping the situation by repeating it again.

I have a Brother laser, which comes perilously close to disastrously melting the adhesive vinyl-on-paper I use for toner transfer (which I only do for masking pads if painting, but that's beside the point) which the Oki laser printer in the shed has no problem with.  I only made that mistake once. 

I think it's more than urban myth, but if it's settings, or actually they run the fuser hotter, I couldn't say.

[SeanB]

Fuser temperature is set by the manufacturer, so as to give adequate adhesion to a standard bond paper ( specified in the printer manual as a recommended paper) when run through with the toner blend they use at the speed they run the paper through. Some printers can vary the temperature, so as to enable printing on transparencies ( lower temperature so it does not soften but with a risk of poorer adhesion) and a setting for T shirt or photo paper, which runs hotter as the transfer paper or photo paper is higher mass thus absorbs a lot of heat. Some have the fuser temperature settable in the printer UI or control panel on the printer ( might be a paper setting) so you can adjust it.

[wasyoungonce]

Do you just keep a small amount of toner in for each print and discard used toner?

I have a hl2040cn, but haven't tried it for pcb transfer yet

no i just use what ever is in the toner...a mix of old and new.  I do keep a refilled toner ready to go (fleabay toner refill) but that is because of my kids at UNI printing all the time.   I have no trouble with the brother even though it returns unused toner back to the toner cart.   Works for me.  But the high temp laminator I made up is the real hero for me.

[nshin31302]

Why do you say that? I think it is an urban myth and you are not helping the situation by repeating it again.

I found this site http://www.pcbfx.com/main_site/pages/start_here/printer_info.html that states

however...the entire BROTHER printer line does not work with our PCB process.

but after a bit of research, the results are mixed from perfect to disastrous. Also, the brother printer that I have (the HL-3170CDW) is a Color printer, which is reported to have a different toner composition than normal toner, resulting in being incompatible for PCB making, without

(jumping) through some hoops

[Votality]

Why do you say that? I think it is an urban myth and you are not helping the situation by repeating it again.

I found this site http://www.pcbfx.com/main_site/pages/start_here/printer_info.html that states

however...the entire BROTHER printer line does not work with our PCB process.

but after a bit of research, the results are mixed from perfect to disastrous. Also, the brother printer that I have (the HL-3170CDW) is a Color printer, which is reported to have a different toner composition than normal toner, resulting in being incompatible for PCB making, without

(jumping) through some hoops

I will eventually give it a go with my colour brother 2040 or 3040cn (sorry don't remember the model off the top of my head) and report the results

[Votality]

Anyone here from Australia? What paper do people recommend using.

Is there anything cost effective?

I have seen people suggest using gloss laser paper (Any i could find here is as expensive as the commercial pcb transfer paper (the blue stuff)) to using normal paper then soaking it in water to remove the paper.

[IanB]

Anyone here from Australia? What paper do people recommend using.

Is there anything cost effective?

I have seen people suggest using gloss laser paper (Any i could find here is as expensive as the commercial pcb transfer paper (the blue stuff)) to using normal paper then soaking it in water to remove the paper.

I recall many recommendations to use the thin, glossy printed paper used for the advertising flyers and circulars that relentlessly come in the mail. It is free, the shiny surface easily releases the toner, and the thinness makes it easy to remove after the transfer is complete.

[Psi]

you can get good results just cutting up a glossy magazine and printing on that.

It doesn't matter that it already has text/pictures on it. The toner gets layer on top of the gloss and doesn't stick all that well, which is what you want.

[Kappes Buur]

Glossy paper, magazine or photopaper, never worked for me reliably.

This works well and is very easy to use
http://www.dipmicro.com/store/PNPB

[wasyoungonce]

And I'll say it again. Toner melts/softens at around 130 degrees Celcius so pre-heat the PCB to about 70-80 degrees so it is at least too hot to handle by hand.

I'll 2nd that as well!  I use a hot air gun on the PCB to pre-heat them...a bit dodgy and makes them difficult to handle putting down the paper and taping it with Kapton tape..."trying to keep it all lined up".   So I make my PCBs oversize and cut them down after etching.   I really need a clean reheat oven.

[KerryW]

Here's what I do:

Print to glossy magazine paper  Use highext density printing available.  Don't touch surface of paper.

Clean copper qith 00 steel wool, then wash thoroughly.  Don;t touch copper.

Transfer using laminator (preferred) or iron.

Soak paper off with water.  Rub with fingers and/or toothbrush.

Inspect.  Remove any printing from magazine paper with IPA.  Touch up any missing toner with RED Sharpie.

Etch.

Drill.