Reddit mentions of APOLLO Transparency Film for Laser Printers, Black on Clear, 50 Sheets/Pack (CG7060) (VCG7060E)

I started with the toner transfer method and after getting ugly ground planes, no matter what I did, I decided to up my game and see how I could improve. The dry film photoresist method is great!

Stencil:

• Laser Printer: I got this one for $50,- at the time, price has gone up since then.
  
• Laminator: Cheapest and best laminator I could find - no modding or anything required.
  
• Transparency Film/Paper: This one seemed to work the best out of all the others I bought.
  
  Etch-resist:
  
  
• Positive Developer (Sodium Hydroxide): This stuff is dangerous - it's lye! The solution I bought was pre-diluted 10% and can be found here. My developer solution is roughly 1% lye. That means you need to dilute one part from MG Chemicals bottle with 10 parts water. This has yet to go bad for me.
  
• UV Light Source: I use this cheap one found on Amazon. Works well and is just big enough to fit my largest 4"x6" boards.
  
• Dry film photo resist OR pre-sensitized photo resist boards: Pick any that you find will suit your purpose. I found some lying around at my university and have no idea where it came from. I've heard good things about Riston (eBay), and we use the pre-sensitized boards made by MG Chemicals at my university.
  
• Other: Rugged rubber / "vinyl" gloves, safety glasses (you should own these already if you solder), a respirator if desired, lots of plastic containers such as Tupperware big enough for your PCBs, acetone to clean the copper boards and to remove the photoresist, reasonably heavy duty scotch brite pads, and glass from a picture frame to hold the transparent stencil onto the board.
  
  Etchant:
  
  Here it really is up to you. I use the hydrochloric acid (muriatic acid) with hydrogen peroxide method, but any method will work fine. Be careful that your etchant isn't too strong and will somehow inadvertently strip off your photo resistive etch-resist!
  
  I hope I didn't forget anything...
  
  ---
  
  Pros:
  
  
• Cheaper than a CNC by far.
  
• Cleaner results than toner transfer, if done right.
  
• Reusable chemical solutions - depending on your choice of etchants.
  
• Photoresist also allows you to make your own solder masks. Take a look at my previous post here for pictures!
  
• High accuracy depending on your printer. I can confidently get down to about 6 mil before I get nervous with my printer.
  
  Cons:
  
  
• Still somewhat pricey if you have no materials on the list at all - somewhere around $200.
  
• Dangerous chemicals which require proper storage, safe handling, and approved disposal.
  
• Will probably take a few trial & error runs to tweak your procedure in order get good results; same as toner transfer.

Doo-da-doo... make your own!

Glass plate, 200mm, ferrofluid, glass clamp, EL Tape, Transparency film.

This is just how I'd build it - though, 0.2mm film may be too thick.

• Cut a 200mm circle of transparency film, then cut a 180mm circle into that (so you have a ring with an OD of 200mm, an ID of 180mm, and a wall of 10mm)
  
• Clean your glass plates, add the transparency, and measure the thickness of the sandwich without the fluid in, using a micrometer (should be roughly 6.2mm). Trim your EL tape to a strip of that thickness (should be a little less than a third the base thickness of the EL tape).
  
• Place the film onto the plate, and tape it down at the edges. You don't need a seal, just enough tape so the transparency doesn't walk.
  
• Drip 5 mL fluid onto the plate (0.2mm pi (90mm)^2 = 5mm. Get a micrometer and measure the thickness of your transparency film to get the correct thickness; 0.2mm is assumed).
  
• Carefully place the top plate on
  
• Wrap the EL tape around the loose sandwich, using the bottom plate for the majority of your support. Tape it tightly in place.
  
• Carefully add the clamps at 90ᵒ angles along the plate's edge. Clamps should be unable to move from light vibration, but not so tight you risk breaking the glass. The transparency layer helps here.
  
• Apply power, and have fun!
  
  If the transparency layer leave too thick a film of ferrofluid, my second thought:
  
  

• Thoroughly wash a plate
  
• Cut a 180mm circle of waxed paper. Lay it in the center of a plate, and hold it in place with a dot of ferrofluid in the middle.
  
• Use cheap, thin packing tape to make a solid layer, starting from the middle of the waxed paper and moving outward.
  
• Carefully cut away the center
  
• Proceed as above, but using the ring of packing tape instead of transparency.
  
  Also, if you don't like cutting curves, there's no reason you couldn't do this with square or rectangular glass; you just wouldn't get consistent illumination along a given circumference. If I build this successfully, and proceed to design a segment display, I'm going to almost certainly use rectangular glass for it.

Hi, Acetate sheets you'll likely find in the kitchen department for chocolate making. The office versions are usually called Transparency Film. There are two types that I know of, the transparency film for printers and the ones that say 'not for use in printers' and they direct the user to special markers that can be cleaned off easily.

The former, printer version is like this.

The latter, writing and drawing version is like this.

Sorry, I don't know what they're like though. Never tried.

Good luck :)

Hmm well I use an HP Laserjet printer, color ink, and this transparency paper. So far I have had only success. The images come out crisp and in color. They are all slightly see through when held up to light but its not bad at all. The larger minis tend to bend over because it isn't the must sturdy paper ever, but I havn't had a single one get bent in any corners or anything yet.

I've used spray adhesive, but I used it with [this]9https://www.amazon.com/Apollo-Printer-Copier-Transparency-Sheets/dp/B0040YC7FI/ref=sr_1_sc_3?ie=UTF8&qid=1481164639&sr=8-3-spell&keywords=trasnsparency+sheets0 as my stencil.

As long as you LIGHTLY spray the adhesive on it works fine. Spray too much and it's a gigantic PITA. I'd suggest practicing with the spray before doing your project.