Instant and cheap PCBs.

[arumblack]

Hey definitely post back with the laminator results.

that would be cheaper than photographic, though i suspect it may have problems with traces really close together.

[Synapsys]

psytron is right about the toner. I also have an HP LaserJet and I bought an extra toner cartridge that I use just for PCB work. It has lasted over two years and I do a lot of PCB work (mostly analog).

Use of an Inkjet to produce the transparencies is not advised. Inkjets do not produce truly opaque images, which means the UV light will penetrate the image resulting in poor quality traces.

Speaking of quality, all laser printers I have seen have a setting that controls the "darkness" of the printing. The default for this setting is usually medium. It is best to change this setting to maximum darkness, print the transparency and set it back to medium.

About the 'more chemicals', the only additional chemical is the developer and it is not at all noxious. It has no odor. Care is required to keep the developer off things like clothes since it will tend to bleach them. About etching; I use sodium persulfate instead of ferric chloride for all my etching. It also has no odor or noxious fumes like ferric chloride does and it is clear so you can see the etching progress without removing the board from the tank.

It is also important to handle an unexposed board in the 'dark'. With the MG Chemical boards I use a small (40 watt) incandescent light while working with the unexposed board and have had no problems.

Another tip is to print the PCB layout as a mirror image and then turn it over so the layout is correct. Doing this places the toner side of the image directly against the board. If you don't do this the thickness of the transparency allows the UV light to sneak under the image and the results are poorer.

One final thought; use the highest density laser printer you can afford. Mine is 1200 dpi and the results are great. I have used 600 dpi in the past with good results. I would assume that if you had the transparencies done at a print shop using 4800 dpi the results would be even better.

happy etching... :)

[arumblack]

About the more chemicals...yes that's true only developer, IF, you buy presensitized boards.you can buy the photoresisist in bulk and apply it yourself(cheaper).I don't have the book i was reading handy, but it was a kodak brand and there are surely some others.I will check the book(it is at school) and post the recomended type back here. so now to find a cheap laser printer(of good resolution)!

[Synapsys]

You are right about the availability of bulk resist that can be applied to plain copper clad boards. I have never tried out this process myself but here is a link to someone who has.

http://w1.859.telia.com/~u85920178/data/pcb2.htm

[Guest Pasquale]

Check out these tutorials on http://www.tonepad.com -> photoessays or http://www.tonepad.com/photoessay.asp?photoEssayID=11 !

Cool tut about making a PCB

It also includes cool DIY Projects for guitarists!

[Guest psytron]

so i finaly got myself together and tried the trancparentcy and laminator.

here are my results

i put the board in the laminator at approx 1/2 heat setting:- didnt work

i put it throug again thinking the board may take a while to heat up:- still no joy

crank up the power to full and put the board thru a few times:- no luck

put the board in the oven for 2 mins:- plastic film starting to distort from heat only a smaill amout of trancfer and very blurry

went back to ex sticker paper instead of the clear stuff and put the board thru 2-4 times on full power result:-

all of the toner stuck, but due to some movement (bettween passes)when the board goes thru the laminator i have many fine cracks. so i had a little session with the dalo pen and all is good. and nice and fast too i did 15 boards in (2 mins laminator warm up, 3 mins for a few passes thru the laminator, 15 mins with the dalo pen)

the laminator does a great job with a very even pressure, no blurring of any sort. all that needs to be solved is the movment prob. This can be done 2 ways i can think of.

Method 1

get the screw driver and solderer out.

unplug laminator!!!! and let cool down (owch)

open up the beat and place a pot on one of the wires that control the motor.

theory:

if you can slow the laminator down so that it heats up the board enuf on one pass you will have a perfect print.

Method 2

i could stick some of the trancparency plastic over the backing paper from the stickers. then feed the lot into the laminator a few times to heat it all up. the plastic sheet should be stiff enuf not to streach when it hits the rollers.

i will prob give the second method a go as i do not own the laminator.

[arumblack]

Awesome, be sure to report back after you try again.

[shed]

the only laminator that i ever used came with plasticy cardbord folder type things that you were suposed to put anything for laminating inside, that stoped things movining arround so much.

[Fx3_hdrive]

hey guys,

if any1 owns a printer that can print CDs then they pissed it  ;D

i havent tried this method on mine but i think u'll agree that it eliminates all the transfer problems.

ohh there is an idea, rip apart an old printer and stuff a board instead of paper  ;D  DIY style  ;D

Yarek T

[Screaming_Rabbit]

hey guys,

if any1 owns a printer that can print CDs then they pissed it  ;D

i havent tried this method on mine but i think u'll agree that it eliminates all the transfer problems.

...???

I don't know a laser printer for CDs... and I wouldn't buy one. - I think the emmitted light would be so strong, that it would erase your data on a CDR or at least corrupt it partially.

InkJet won't work (doesn't resist the accid)... I don't know about thermo printers, which are available for CDRs ???

I'll perhaps talk to our CD Production Roboter distributor, to test it. - Those printers are available for about $200.-

Greets, Roger

[Fx3_hdrive]

oooh, *shoots self* ur totaly right, inkjets wouldnt resist acid, but how about my second idea? maybe take all the plastic off and make some space between the rollers to stick your board in, dunno what will it do to the toner cartrige with the board being copper.

btw on my laser printer (ML4500 - Samsung) i opened the front, where u can see the heating element and fed the paper manually to make it bypass the heat roller, after that i transfered it using clothes iron and it was pretty neat i must say.

Yarek T

[Jidis]

I've got a portable planer that can handle stock up to about 6" thick. Maybe I can rip the blades out of it and mount a heating element under the metal base. ;D

Seriously though, I wish someone would come up with a good DIY laminator type rig for PCB size stuff. Even manual feed could probably work with some practice. I built a giant motor driven thing that spins drum shells, and has a pair of adjustable rollers from a Xerox machine on bars, so it can wrap drum finish as well. There's one roller against the inside and one out, and it squeezes the laminate against the shell, then you just roll the shell around by hand. If a roller was heated, it might work (obviously not a rubber one). People buy these long, raw oven type elements for doing laminate post forming (corner bending). I remember MCM Electronics having a bunch of different shapes and styles. I think the wiring was pretty simple.

-George

[Fx3_hdrive]

if i get hold of an old laser then i'll try to mod it for printing boards  ;D DIY Style  ;D

open to donations... :P

[Davo]

I've got a portable planer that can handle stock up to about 6" thick. Maybe I can rip the blades out of it and mount a heating element under the metal base. ;D

Seriously though, I wish someone would come up with a good DIY laminator type rig for PCB size stuff. Even manual feed could probably work with some practice. I built a giant motor driven thing that spins drum shells, and has a pair of adjustable rollers from a Xerox machine on bars, so it can wrap drum finish as well. There's one roller against the inside and one out, and it squeezes the laminate against the shell, then you just roll the shell around by hand. If a roller was heated, it might work (obviously not a rubber one). People buy these long, raw oven type elements for doing laminate post forming (corner bending). I remember MCM Electronics having a bunch of different shapes and styles. I think the wiring was pretty simple.

-George

http://www.thinktink.com/ sells laminators that look like the kinds used for laminating paper with plastic, except they're for applying photoresist film.  It looks very quick, easy, and clean.  But, the machines cost a LOT, like US$3000 or so.  They also sell film in smaller quantities (10 meters for US$90), and show you how to apply it using a pouch-type laminator (like what Pulsar suggests for toner-transfer paper).  The Homebrew_PCBs Yahoo group has some discussion on applying this stuff too.  See http://groups.yahoo.com/group/Homebrew_PCBs/message/10669.  In light of not being able to get spray resist here in the US and my horrible luck with toner-transfer, I'll experiment with a setup like this and report back my results.

-Davo

[Jidis]

Davo, (and anyone interested)

I'm going to try to get you those prints out tomorrow afternoon. I'm up 'til 6am, so doing stuff in the day isn't too easy for me.

Don't give up yet on the toner. There has to be a factor that's screwing things up that badly. My results have been getting better and better with some testing, and now that I've fought with the metal transfers, I actually look forward to doing the copper each time. Nothing is usually beyond a couple dabs with a thin sharpie marker, and that will depend on how patient I am at the time and how important the "look" of the board is. If I want to get closer to a perfect print, I can just wipe the toner off a couple times until I get one I'm satisfied with. The cool thing is, lately the most trouble I have with toner lifting off with the paper, is with bold, black areas, like dimensional borders and ground planes. Lightening the contrast looks like it helps, but it would be more conservative and easier just to do outlines and fill the areas by hand or tape them off. My Sharp FO-2850 printer may have something to do with that too. I just found an HP LaserJet 6 in a local for sale ad for $30, and I'm going to pick it up in about an hour. It's similar to what Tom Gootee recommends on that site. If there's a considerable difference in transfers, I'll post here about it.

Some friends here gave me the Sharp, and I foolishly mangled it by running a "cleaning sheet" through it. I may just as well have soaked some newspaper in water and run that through there. >:( It broke a couple of the plastic outfeed rollers and I may have made it worse by trying to fix it. It still prints OK, but the paper has a bit of a bumpy ride through the plastic stuff, and usually gets ruined if I try to print on the backside afterward (it "curls" the ends a bit). I may look into modding it for board capacity, but it's pretty complicated. It's got a fax scanner and a front panel that flips down like a tractor-trailer.

I'll be trying a bunch of new stuff over the week. A bottle of Sodium Persulfate crystals just got here, and I've started building one of those Plexiglas etch tanks. Someone here also recommended attaching a smooth flat metal (aluminum) plate to my iron, to help spread the heat more evenly. The steam holes in the bottom are more dangerous than I thought. I've been squashing a wet paper towel onto the paper with my iron, after the main heating, and there are big round lumps where all the holes were. They could very well be the reason for some of the problem traces, as two of the main heatings are with the iron held firmly in one spot for a while. I'm also thinking of mounting a flat plate to a bathroom scale, so I can do my ironing on that and monitor the pressure/time ratio during the transfers. I've already put one on the counter and checked with a "push-up" (exercise) handle thing, and it looks like my pressure is in the 30-40 pound range for the initial heavy pressure and maybe in the 20's for the spot heating.

Since the toner is adequate for a bunch of us, I've wondered if there might be an easier machine than a printer to modify or build, which was more like the iron method where the object is stationary. The guy that recommended the plate on the iron also mentioned a heat press (he makes shirts). I looked it up, but they're in the $500 range. I'm wondering if you could adapt something like a waffle press or a George Foreman grill to do PCB size items. It seems like it would only be a matter of replacing the grooved crap (if it has some) with flat surfaces. Somebody sells plans on eBay for something like that, but it looks big and "wooden". I think the size of T-shirts makes their stuff bigger and more expensive. Our stuff could probably fit in something smaller and more solid, if we could find good heating elements.

                         Sorry for the long post (just excited :) )

-George

PS- I'll probably be heading for that Yahoo group soon, and maybe the electronics newsgroups. I'm thinking there may be someone that could help me get the metal transfers going.

[Fx3_hdrive]

as i mentioned earlier i pass the paper with the artwork through the priner while its open (i press a switch on the side with a screw driver so it makes the prinet think its closed) and with another screw driver i bypass the heat roller and the paper comes out, it looks just like an ordinary artwork but if u touch it with you finger it would smuge, the toner is just sitting there like dust, all with perfect resolution

then i preheat the copper side of the pcb and slap the paper on it, the toner starts to adhere to the copper and then i just go crazy with the iron  ;)

hope that helps

Yarek T

[Goblinz]

**Superbump!**

I've found a tutorial on using a laminator and magazine paper for ransferring toner onto a PCB. This seems like the most appropriate place for it.

http://fahque99.googlepages.com/board.html

    G

[SLP]

**Superbump!**

*whack*

[cimo]

as i mentioned earlier i pass the paper with the artwork through the priner while its open (i press a switch on the side with a screw driver so it makes the prinet think its closed) and with another screw driver i bypass the heat roller and the paper comes out, it looks just like an ordinary artwork but if u touch it with you finger it would smuge, the toner is just sitting there like dust, all with perfect resolution

then i preheat the copper side of the pcb and slap the paper on it, the toner starts to adhere to the copper and then i just go crazy with the iron  ;)

hope that helps

Yarek T

hi i d like to know more about preheating roller bypass and other tricks could you explain that better?

[stryd_one]

@anyone who doesn't know: You could electrocute or burn yourself rather badly doing this. Don't try this at home, kids.

[Matrix12x]

I just tried today using HP premium paper put into a photocopier, it worked great, and the paper is very stiff, so I didn't get the same problems I got with the cheaper photopaper getting wrinkly in the middle.

I touched up with a sharpie.

The etching worked out fine.

[drboom]

nice, but still a waste of money!. i get even better results with certain types of magazines, 90% of the time dont even need touch ups.

for the aus people. "the road ahead" magazine is the best.

and forget the iron. a sandwich press works awesome. of course pressing times depend on many variables, type of paper/printer/heat etc etc etc. its a suck it and see thing, i just kept records on what i used and how long i cooked it for till i got it right.

ive made most modules with this method, core, burner, dout, din, sid, ltc. works great.

theres a great yahoo group (http://tech.groups.yahoo.com/group/Homebrew_PCBs/) that is very active and has a database of materials that can be used for diy pcb's, paper/laminators/printers etc. there is even some dudes using modified inkjet printers to print a special chemical directly onto blank PCB's to avoid having to transfer. they get some VERY fine lines using this method.

BTW: dont use a sandwich press with that pressnpeel blue garbage.

BTW2: Some Newer brother laser printers use a different kind of toner, requiring ALOT of heat to transfer. they dont work at all with normal paper or press n peel blue no matter how hot you try to get them up to. i found this out the hard way.

[Matrix12x]

I am going to try the magazine idea tomorrow.

[drboom]

dont be afraid try many types of mag's. even if they look similair gloss/feel etc. Also, dont worry if your using a black page. the magazine print wont come off no matter how hot you make it.

some paper types also will stick with the toner making it a little difficult to remove the paper. i soak the pcb in some soapy water for a while and massage it off with a toothbrush to get the excess paper off after i have heated it to the board.

All i can say is, dont just try one and come back saying it doesnt work. you have to be prepared to experiment many times to get it right for your setup. KEEP NOTES in case you forget!, use a stopwatch. and increment your heating times by 20 seconds every time you retry.

1 more thing, cant stress this enough. CLEANLINESS!!, sand your pcb with 400+ grit wet/dry sandpaper using a sanding block and get that baby to shine, and flat!, and before you transfer clean the surface of the plate with wax and grease remover (sometimes called prepsol). 

[napierzaza]

I got some very cheapo laser printer paper from Staples and it works fine! I've even done double-sided boards and they work perfectly, but you may screw up a few times over and have to clean it up and redo it. After 2-3 you get the hang of it. This method can be detailed enough to do SMD spacing even as I've tried it. I find 5-10 minutes at least. Buy some nail polish if you need to touch up any errors where it peels off.