Poor Man's Photo Etch
POOR MAN'S PHOTO ETCH
Brothers and Sisters,
Need some fittings for your beast. What they don't make that? It costs howmuch? Do it your self. Photo etch is easiest when you apply the KISS theory.
I modified the storage bin on my Tiger since the Heng Long as molded isincorrect. To do this I have to sand the top and fill in the new extensions. SoI decided to try my own photo etch.Here is what you need:
1. Ferric Chloride (PCB etchant Radio Shack)
2. Plasti-Dip Any color; brush or spray is fine
3. Alcohol
4. A small bit of an old magazine. The cheaper the better. Look for large areasof all white.
5. Clothing Iron or wood burner with transfer button
6. Tape
7. Steel Wool
8. Basic Drafting tools
9. Small bottle of enamel paint. Any color is fine.
10. Brass of the thickness and size you need.
11. Two plastic trays. The take out trays work great. About 2 inches deep.
12. Chemical Gloves
13. Eye Protection
14. Plastic tweezers
15. Ventilation
* Optional
Fish Tank air pump and hose
Wooden Clothes Pin
Thin plastic or rubber mat
Heating Pad
First thing is to do some basic drawings of what you want to make. Be sureyou draw your items at least three time size you need. Do not worry about yourartistic talents we have ways of taking care of that.
There is a free but powerful image manipulating software called GIMP. Ithas all the tools you need to make anything you need.
Scan your drawing then open it in the GIMP program. It would take me about100 hours to explain all the features so I will let you play with it and learnthe way I did.
However there are a few tips I will share. Once you have your basic sketchturned into your basic master pattern you can do one of two things. If youinvert the black and white you will create either parts or a stencil. Anythingblack will be protected from etching, where as the white will be removed.Either is very useful, for making marking stencils or parts, or nameplates,,blabla....you get the idea. The next thing is to make the little creases for youto be able to fold your finished parts. To do this make as small a white lineas you can where you want the fold to be. We will talk about why in a second.Also if your part needs holes make sure they are white. When you are satisfiedclick view and increase the zoom. Look for Pixels that are a little off ofblack or white. Redo these area until both black and white are as pure as canbe.
Now using you laser printer, make a copy. Remember we are still at 3 timesthe size you need! Look over the printed copy note anything wrong or add a partor delete something.
If everything checks out reduce the image to the size you need. Now print acopy of the image at the scale size. Still okay?
Take the magazine page and cut it a bit larger than the image. Tape theMagazine cutout over the image. Be sure the tape is flat!
Replace this page in your printer and print a copy so that the image is nowon the magazine paper. You see magazine pages are coated in plastic. When youlaser copy the plastic melts slightly and soaks in the plastic of the image. Sinceetchant does not attack plastic you just made your own photo resist!
Carefully un-tape the image the magazine paper from the printing paper.
Prepare your brass. Give it a buff with the steel wool to give it just abit of a tooth. After that use the alcohol to clean it up. When it is clean besure you do not touch the surface!
Tape the edges down on a flat smooth bit of wood. now place the image onthe magazine sheet, be sure the image is face down and in full contact with thebrass. Carefully tape this down.
Now to transfer the photo resist image we made to the brass. NOTE: Thispart is more art than science, so take your time!
I use a transfer button on my wood burner, but you can use an iron also.
If you use an iron be sure to empty any water from it and do not set it onSteam. Remember we are melting plastic not smelting pig iron so use a lowersetting. It may take more time but you will avoid problems such as warping,burning the paper, setting the house on fire, and other problems.
When your heating device of choice is heated up. Rub it over the imagegently. Work the iron back and forth, up and down. It should take about threeminutes. What is happening in the plastic on the image is heated and melt, Thebrass heats also and becomes hotter than the paper. The brass treats itsomewhat like solder and soaks the plastic and you image in.
Remove the heat and let it cool to room temperature. DO NOT TRY TO PEEL OFFTHE PAPER!!!!!!!
When the brass is cool run it under tepid water. The remains of the imageare now mostly paper and we are using water to dissolve it. Give it a littlerub with you fingers to help it along. You will never get all the paper, butget what you can.
Carefully lay the brass on a square of cardboard face down. UsingPlasti-Dip, apply two or three coats, allowing each coat to dry four hours.
What you have now done is sealed the back of the brass with rubber. Etchantdoes not eat rubber so the area of brass that will become our parts isisolated. This also removes the need for frets, so you do not have to trim theparts. Your parts will be on the rubber. Trust me they are not going anywhere.
Alright here we go. Etchant works better and faster if it is warm andagitated. (My wife is the same way.) NEVER EVER EVER NEVER heat etchant on a stoveor in a microwave!!!!! Boil water, take it off thestove and place your bottleof etchant in the water, letting it heat the etchant.
You can set up a heating pad covered with rubber and to keep the etchantwarm during the process. Just be sure you do not spill any. Agitation can be aFish tank air pump turned way down. Put the hose in the bottom of the tray,secure it to the side with a clothes pin.
Now is the time to have the other tray filled with clean water.
With the etchant heated, place the brass face up into the etchant. Afterthree or four minutes remove the brass and place it in the water. We juststopped the reaction. Why? Remember the fold lines? the etchant has dissolveddown to where we need and now we need to protect the lines from further etching.To do this we use enamel paint to fill the lines thus protecting them. Let thepaint dry before you go on.
With the paint dry return the brass to the etchant. Monitor closely, bylifting it from the etchant to check progress. When the brass around your partsis gone. Remove the brass from the etchant and place it in the water.
Almost there!! After a five minute soak. Pat dry the brass. Lay it flat.The rubber will make it all floppy. now you need to find a thinner to removethe photo resist we made. Finger nail polish remover works good, but find aproduct that works for you.
With the resist removed you now have your parts....but, give them a littlerub with the steel wool and another rub of alcohol.
When the part is needed just lift and peel it from the rubber backing.
Well there you are! Enjoy!
Last edited by torpedochief; 09-15-2014 at 07:48 PM.
Reason: Pictures not in order and no idea how to change them