What am I doing wrong with the PNP Blue transfer?

[EBK]

I'm trying to use PNP Blue to transfer an etch mask onto an enclosure, but each time I try, I get an incomplete transfer.

After a third fail, I figured it was time to ask for help.  Any suggestions?

[EBK]

A bit more info:
The enclosure surface is sanded flat (I'll have to check the grit of the sanding pad, but it isn't mirror polished).
The surface is scrubbed clean with pure acetone before each attempt.
I'm using my household iron on its highest setting, with a double layer of parchment paper between it and the transfer film.  I have left the iron in place for a few minutes before moving it, then I move it sparingly (on the first attempt, I smeared the toner, which I'm trying to avoid).  I have tried quenching the ironed enclosure in cold water, and I have tried letting it cool down on its own. 

[Mark Hammer]

I think the problem is that you're using something that requires heat to transfer material from one surface (the sheet) to another (the enclosure), but the surface you're trying to transfer to is fundamentally a heat sink, so the required heat to transfer things can be easily dissipated.

The question is: how to heat the enclosure up in a uniform manner?

[davent]

Would preheating the enclosure in the oven be a help?

Rob, @deadastronaut is the first person that comes to mind as the leading light here on enclosure etching.
dave

[EBK]

I succeeded with this stuff quite a while back, but I didn't take good notes so I can replicate it. 



I at least know it is possible to get a good transfer with PNP Blue and the iron I own, which makes failure more frustrating.   

I think I was following a tutorial from the Gallery page back then (maybe...), but I can't find it anymore.

[EBK]

I think I'll give it another go with a lower iron setting.  Perhaps I'm deforming the film by heating it too quickly.  Just a wild guess though.

[bean]

From your description it seems like you are doing everything right. But, maybe you went too far on sanding prep? I usually use 220 grit then finish with cross hatch sanding. This leaves a rough enough surface for the PNP to grab onto through heating. I also use the highest setting on the iron and start with a single sheet of copy paper over the PNP. After a couple minutes of that I go straight to the PNP with the iron and use the tip with pressure to really get it baked in.

Even with all that you can still get splotching like in your pic. What I usually do is apply shaprie to those areas in two passes. Then take a bit of clear shipping tape and cut small pieces to cover those areas to ensure the etchant doesn't get to it.

Lastly, cover all the sides with shipping tape and use an eye dropper to apply etchant just to the top surface (IOW don't fill a tub with etch and place the enclosure face down). You only need a tiny bit of etchant applied to the surface and if you are careful it will stay in place and not run down the sides. If you use this method you can get a good etch in as little as 3 to 4 minutes.

[willienillie]

Have you tried NPN?

Are you daisy chaining?

[bean]

Have you tried NPN?

Tee-hee 

[EBK]

I'm still working on this problem, but I think I'm getting closer:

I roughed up the surface a bit more and switched from an iron to a small heat press.

Still not what I'd call "good".  I'm going to try an even rougher surface and perhaps a lower temperature, unless anyone has any other suggestions.

I think I've had 7 failures so far. If I get to 10, I'll probably just quit and go back to decals.

[deadastronaut]

how about just touching it up with nail varnish?


my guess is it needs a coarse grit sand..like 180...to get a good grip.

then use a finer grit once etched....which is what i do when etching/toner/ferric.

[EBK]

how about just touching it up with nail varnish?

I almost could, and I did consider it. I'm not worried about the spots away from the letters (I need to manually fill in the intentional voids anyway, so a few more dabs of paint are nothing), but there are a few areas I don't think I could neatly fix, specifically the DC jack label, the "M" in "LEMON", and the "S O L" switch label.  I am willing to forgo the DC jack label, if necessary.

[davent]

Art supply shops sell extremely small brushes that give you a better chance at fine fine detail painting and if you do stray a razor edge like a #11 Xacto blade can fix that after the paint/nail polish has dried.

15/0, 10/0 sized brushes...
eg.

https://www.micromark.com/Micron-Brush-Set-1?gclid=Cj0KCQiAvvKBBhCXARIsACTePW9v11xoI75Xq7eh6L7emff8KtfkDIRD36hFl-9EXiDjbskLDMbt1OkaAhqlEALw_wcB

I need a 10x jeweler's loupe to be able to see well enough and have one i can hold in my eye socket, hands free, to do fine work.
dave

[slashandburn]

I don't have an answer to your issue but I always found Press n' peel Blue to be a nightmare to work with. Really delicate (warps under too much heat like you said and scatches easily. I'd often find I'd scratch the unused sheets just by placing cuttings back in the packet) and ludicrously expensive compared to other options. That said  there's every chance the stuff I was using was substandard and overpriced (Maplin).

Cheap Glossy photo paper is my goto now whenever I'm etching (which is not all that often if I'm honest) and I haven't had half as many issues. Now and again I'll get a bad transfer and need to start over but it's so rare (and cheap compared to PNP blue) its much less of an issue.

[EBK]

I think I'm going to put this project back down for a while.  I don't feel like trying to fix things like this:


When I pick it back up in a month or so, I will probably give glossy photo paper a try. 

[deadastronaut]

^ ive never had a bad result with cheapo glossy 150gsm paper

as long as the toner save is turned off, and its set for best /thick quality

it should be fine.


i recently bought a new toner cartridge for my samsung ML1660 cheap, was £10.00

when i first bought my printer the cartridges were around £100.00 so i took a punt on the cheap replacement

and its just as good as the original cartridge...result.

[EBK]

Is there a particular brand of photo paper that works well?  Does it matter if it says "for Inkjet"?

[deadastronaut]

i use any old photo paper......so i doubt it matters.

as long as it has a sheen on it...

[davent]

Does press and peel have a shelf?

With the art you're using you've got three distinct sections, what  if you cut your art into three pieces and applied one at a time instead of trying to do the whole of the top all at once. Then too if one section comes out sucky you just have to fix up one rather go back to square one every time.

Haven't tried doing an enclosure and my experience using commercial product for toner transfer to pcb were abysmal so i moved on, no expert...
dave

[EBK]

With the art you're using you've got three distinct sections, what  if you cut your art into three pieces and applied one at a time instead of trying to do the whole of the top all at once. Then too if one section comes out sucky you just have to fix up one rather go back to square one every time.

I thought about doing the heating in sections.  The thing that stopped me is the knowledge that it is possible (somehow) to get a perfect transfer with this stuff (see my Reply #4 above).

Anyway, I've ordered some cheap glossy photo paper, and I will report back.