Laminator Not Hot Enough?, Heat it with hot air gun.

It's been awhile since I've posted on my journey into DIY PCB etching.

I guess the initial excitement of making my own PCB's at home is starting to wear thin, while my sympathy for those 10-year-olds in the Chinese factories is starting to grow.

Anywoo, I've discovered that my stock GBC starts to get really sketchy when the board gets much bigger than a few inches per side, using magazine paper. And it starts to fail miserably with PNP Blue. It just doesn't get hot enough.

But I've found a to increase the heat without modding the laminator. I can run an entire 8x11" pcb c PNP through a laminator with just 4 passes! Just a FYI, in case someone else might find this info useful:

1. Run the blank board through once, to preheat
2. Put tranfer medium on and run it through again. It should tack down and stick pretty good, because of the preheat. If you don't do a preheat, you risk partial separation on the first pass.
3. Now, run it through face down, while shooting the back of the board with a hot air gun. Try not to melt your laminator.
4. Reverse direction and repeat step 3 as many times as necessary.

I have a GBC laminator and have never had a problem, but then maybe I haven't done big enough boards.

One thing that I have discovered though, is to let the thing warm up for at least half an hour. Even though the ready light comes on a few minutes after you turn it on, it's not hot enough to do PCBs and it will continue to heat up.

I agree. I let mine sit a minimum of 20 minutes turned on before I put a board through. I have done several boards at around 4" x 6" without any problem. Thanks for the tip with the hot air gun though. I hope that I don't need it. And yes, the fun of making your own does wear off after awhile, although it's still a lot cheaper when you are making 1 or two prototypes.

I recently started etching boards again via magazine paper and laser printer.
First try and my 17 mill traces turned out pretty well.
I think that's about as small as I can reliably go, with 7-10 mill for one ounce board.

biggest issue was getting the toner to stick to the board.
I used a typical cheap clothes iron, but the bottom is not flat, so I used a diamond knife sharpener to make the iron flat.

From there the board was placed on top of a cloth rag, supported by a brick, the paper on the board with a layer of tissue paper on top and a 20 pound transformer on top of the iron to press it (~3psi)
End result was that although the board is smooth, it wasn't flat, every 50 mills in one direction the copper is a ten thousandth of an inch higher, in the future I will have to smooth it out with a flat grinding stone. (which is also what I used to take the toner off the finished traces and that worked out real well)

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you may notice the bends in the trace leaving a gap. Kicad sucks. those aren't there on on the board editor, they have round edges.

edit: staedtler permanent marker for the touch up. it don't work that great either.

One technique I use when I need something totally flat, is to lap it flat on a piece of very fine wet/dry sandpaper on a piece of glass supported by plywood. Using wet lapping, the cutting rate is fantastic. If random swirls are used, the lapping comes out even all across. A machinist's granite surface plate would be much better than a glass support, if you have one. They aren't very expensive anymore & offer surface flatnesses in the millionths of an inch range.