Laser printer for PCB question

Hi

Many thanks for the detailed and helpful replies. I'll give it another shot since I have almost a full pack of blue Press-n-Peel to go.

I'll try cleaning with acetone and chamfer the edges of the boards which I wasn't doing before. I use a really good guillotine which cuts downward from the copper side so I'd assumed any burrs would be downwards away from the copper. However, this is no extra effoprt to do just to be sure.

I haven't seen an iron that doesn't have a thermostat though. I think they all do since they burn your clothes if the temp just keeps rising.

Press-n-Peels, once I can get it to work, would be just the right method for what I do which is small, single sided boards.

Thanks again.

Trevor

I tried it out today and got perfect results using the above instructions

no more UV for me

wizpic

Hi

I'm in the middle of making a UV exposure unit and had thought of using glass for the platten. I read one of the posts here saying that glass was not UV transparent and that Plexiglass (Perspex?) was the correct material. Can anyone confirm this, please?

The Farnell ready made units used Perspex as far as I can tell but other people who have made their own recommend glass as more scratch resistant which is why I would prefer it.

I'm still trying to get decent reults with Press-n-Peel but so far it's been a disaster. I honed the surface of my old clothes iron till it was really flat and smooth and this helped a bit but either the traces smear (too hot?) or rip up badly.

The next thing I'm going to try is transferring the toner from coated paper with acetone as described in this thread but meanwhile carry on with my exposure box.

Thanks to all for all the great info on PCB making.

Trevor

Trevor could you write the procedure you use when you try press & peel,I'am really sorry it's not working for you and can't understand why it's not working as I've made some excellent boards using this method.I can tell you that the time depends on board size ie. the bigger the board the longer you iron,for a small board I would just let the iron sit there for 2.5 min or less for bigger boards up to 5 min, but i lift the iron and move it around the idea is to re melt the toner so you have to leave in the same spot for roughly 30 seconds than the next area and so on trying to go over the same spots at different angle's.DO NOT IRON IT LIKE A SHIRT.just remember when you first start to go over the whole board just long enough in each spot to secure the whole piece of press & peel to the board than go back over it slowly leaving it for 30 seconds or so in each area.one other thing to try is making a photocopy instead of using a laser jet to see if it helps,i personally use photocopy's because the toner seem's to be better .hope this helps

:bbarney

I wonder if anyone has tried this with one of those roller laminating machines?

They can be obtained in the Uk for less than £20 now, which if it made a good even coverage would IMO be quite good to apply heat on the board.

I've run across a few websites that have tried that and it seems to work.I'll have try and find the sites again and post the address's

Bbarney

Thanks for the concern and help. I don't think there's not much I can say about the procedure that would be all that revealing. I'm polishing the board with steel wool till very smooth and clean and de-burring the edges so the iron lays flat. I use a small piece of 3/8" thick alloy sheet as a base surface.

I tried again tonight 9 separate attempts to get a small layout to transfer (13 holes, track width 40mils throughout) but with pretty much the same consistently poor results. I rested the iron on the artwork without moving it around for periods ranging from 2 to 5 minutes. On some of the attempts I applied light pressure with a hand on the iron.

The best of the bunch was useable but still had slightly ripped tracks. In almost all cases the pattern looked uniformly black through the plasic before I peeled it off. On one attempt there was some spreading or bleeding of a track where I'd applied a bit too much pressure.

It's beginning to look as if my Laserjet 1022 can't lay enough toner down. Either this or there's something else I'm missing. You mentioned using a photocopier which I haven't tried yet. When you use a photocopier, what is your artwork printed on to begin with - normal paper or something better?

Thanks again for the help.

Trevor






Trevor could you write the procedure you use when you try press & peel,I'am really sorry it's not working for you and can't understand why it's not working as I've made some excellent boards using this method.I can tell you that the time depends on board size ie. the bigger the board the longer you iron,for a small board I would just let the iron sit there for 2.5 min or less for bigger boards up to 5 min, but i lift the iron and move it around the idea is to re melt the toner so you have to leave in the same spot for roughly 30 seconds than the next area and so on trying to go over the same spots at different angle's.DO NOT IRON IT LIKE A SHIRT.just remember when you first start to go over the whole board just long enough in each spot to secure the whole piece of press & peel to the board than go back over it slowly leaving it for 30 seconds or so in each area.one other thing to try is making a photocopy instead of using a laser jet to see if it helps,i personally use photocopy's because the toner seem's to be better .hope this helps

:bbarney

when i photocopy i use regular inkjet paper.i'am thinking that your iron is way to hot,its Likely that your turning it to the right setting but it is hotter than what the setting say's.the only way the toner will run is if its to hot in which case you have to cut your time down.to be honest with you I never had ant luck using a laser jet the toner heat's up to fast and RUN'S that's why I use photo copys PLUS THE TONERS ALWAYS FRESH AT Staples or Office depot or where ever.I use a dish towel folded in half to iron on,may be it cushion's it? and some people put another piece of paper on top the P&P paper.let me know how you make out

Bbarney, Thanks again. I'm going to try photocopying onto the P&P paper later this week when I can get to a photocopier. Can you specify exactly the paper you use. I'm not sure what "regular inkjet paper" means.

As well as the Laserjet, I also have an HP PhtoSmart 7660 inkjet and use HP's Premium glossy photo paper for printing photos. Would that be ok to print the artwork on in the Laserjet?

Regards

Trevor

yea that inkjet photopaper will work great,i use that when i do really fine boards with small tracks,for larger tracks just any old paper will do.remember to play with the heat settings.good luck
bbarney