Laminator in the UK for PCB making

[NilByMouth]

Hi,

I need to make a large (23 x 12 cm) double-sided PCB and looking to use a laminator to do the print transfer. Has anyone had success with any laminators that are still available for sale in the UK? All the ones I've seen mentioned in blogs and forum searches are no longer available.

Thanks

[tautech]

Any A4 laminator should do the job, I always do 2 passes and with toner transfer experimentation is the key to getting acceptable results. Practice on some scrap PCB to get your processes sorted. 

[tggzzz]

Have you considered the acetone+IPA solvent method as a way of avoiding the need for a laminator?

I haven't tried it, but I will do the next time I make a PCB at home.

[rob77]

double sided 23x12cm is quite a challenge for toner transfer... don't expected goood results.
i strongly suggest to go for Riston dry film photo-resist and dynamask dry film solder-mask.

[tggzzz]

double sided 23x12cm is quite a challenge for toner transfer... don't expected goood results.

AFAIK the only real issue is registration, and that can be solved by

• having wire-sized fiducial holes near each corner
• drilling the holes
• pushing a wire through the hole
• aligning the paper with the hole on the each side by poking the wire through the paper
• and holding the paper in that position during lamination

Not perfect, but good enough for 0.1" pitch components - which is as good as the lamination technique allows.

[AndrewDojo]

After my preferred laminator recently broke and the replacement (same model number but clearly revised internal design) turned out to be unsuitable, I tried the acetone+IPA solvent transfer method.

While the toner was transferred very nicely and thoroughly, there were serious issues with porosity of the toner which left significant pin holes throughout the etch and limited the size of the final tracks - fine tracks (8mil) were being eroded to the point of being broken.  For large track through-hole designs it might be acceptable.  But for fine track SMD work the method was not viable.

I ended up buying a used heat press (intended for t-shirt transfers) and found it does a brilliant job.

I use the "Press-n-peel" product with great success: http://www.techniks.com/ when combined with the heat press and a small air compressor.  It is *essential* to eliminate dust between the PCB and the transfer film as any specks of dust have a tenting effect, so a good blast of clean air takes care of this.

Having said this, I do plan to move to a riston film type process.  The heat press will be useful for that as well.

[KL27x]

AFAIK the only real issue is registration, and that can be solved by

Have you ever done it? What kind of laminator are you using?

The real problem with boards this big is the thermal conductivity of copper. If your laminator can do a board like this, no problem, then it's a beast.

I do boards 15cm x 23cm, all the time. (9" x 6" on my side of the pond.) I took the laminator out of the plastic case and screwed it to a plank of wood. Then I shoot the board with a 1200W heat gun as it goes through the preheat. Then transfer it with no air. Then I do it one more time while shooting it with the heat gun. For a double-sided board, same deal. I shoot directly over the (dextrin) paper, AFTER it has been tacked to the board with no air.

For a board this big, I'm using full power on the heat gun and kinda waving it back and forth in a consistent manner, right where the board enters the laminator. For smaller boards, you can definitely overdo this and even get the toner to burn.

I know when it's hot enough when the board is too hot to handle by anything but the edge, when it comes out the other side. It's like cooking. It takes a little trial and error. And cooking a 20 lb turkey takes longer than reheating a tray of taquitos. With a thick copper pour, it might even take more than one pass.

For a board this size, I really doubt you can do this consistently without dextrin coated paper and a pre-etch on the copper clad. It makes a huge difference in the quality, and you can't skimp on a board this large. 95% yield on a small board might be <50% yield on a large board. As you go up in size, it pays big-time to go the extra mile on the finer details. Scrubbing and re-doing a board is a lot of time and effort that is wasted. I have probably done my last 50 boards in a row with maybe only one minor mishap (salvageable) when I got particularly sloppy. I have no affiliation with Pulsar dextrin-coated toner transfer paper, but I will highly recommend it. It saves me more time than it costs. I'd probably still be buying it if it cost 5x as much. And I used to buy PnP "blue" by the 100 pack. Still have 30-40 sheets of it left, and it's not even worth my time to use it up. I really hate buying Pulsar in 5+ 10 packs at a time, though. They really need to do a bulk size, lol. I'm paying as much for the packing as the paper, I'm sure.

FWIW, my laminator is called a GBC Creative. I have been using my first one for about 6 years, now. The only other modification was to take it apart to egg out the holes for the top roller, to allow room for a full 0.062" board + two thickness of transfer paper without skipping teeth on the gearing. The spring contact still presses on thinner boards. I do 0.007" boards on the same laminator with no problem.

To save time and money, I precut a lot of it into 4x3" squares, a bunch at a time, tape those to printer paper, and load them into a dedicated pcb printer, ready to go for my smaller protos. If my pcb is smaller than that, oh well.. I can do a small panel or I can just waste the extra paper. I used to make at least 4 of a pcb in my pre-Pulsar days, just in case one came out wrong. But those days are gone.

[rob77]

exactly the thermal conductivity is a big problem causing uneven transfer. even if you pre-heat you can't expect 100% yield and in most cases you'll have to correct the transferred image with a marker (fill the spots and cracks caused by imperfect transfer).
and actually that's the reason why i switched to dry-film photo-resist.