How to create an overlay

This is the procedure I used to create the overlays for VeCaves.  It took at lot of trial and error to get a good result, and I encourage any other programmers to mess around and see if you can create something better.

As you will see below, this method does not lend itself well to producing reproductions of the original overlays.  This is intended to create multiple copies of the same overlay.  You can use this for creating slightly modified versions of the original overlays, but it takes a bit of setup for each overlay you do.  Click any picture for a larger version.

If you liked this page, or are creating your own overlays, I would like to hear about it.

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Materials:

Transperancy Film
Laminating sheets
Paper cutter
Sleave    Sleave labels

Step 1:
Create the overlay design.  I used Corel Draw, which is a professional drawing program.  The primary advantage of using a drawing program like this is that all the parts of the image you draw are stored independantly as objects.  This is unlike a simple picture editing program which adds the new drawings over the original.  This method allows you more flexability in creating the design as parts can be moved around, and placed on top of each other in any order.  Another key advantage is that all of the drawn objects are based on lines and curves from point to point.  This means that the result doesn't have a 'resolution' per-se.  This is good because when you print it, the 'image' will automatically take on the resolution of the printer.  If you do decide to use a picture based drawing program, be sure to make your resolution high enough so that you don't get an interferance pattern when you print it.

No matter how you do it, create your image keeping in mind a couple things:

Step 2:
Print the overlay.  Use a good quality photo inkjet printer.  Again the goal is to get a lot of ink onto the transperancy.  Typically this is done by setting your printer for printing onto a transperancy with a quality of "best" or "photo".

Here is the result set on a piece of white paper to make it visible.
Printed Transperancy

Inkjet transperancies are made to only print on one side.  This side is made with a special textured surface to accept the ink and allow it to dry.  When you load the transperancy into the printer make sure you load it properly to print on the correct side.  Check the directions included with the transperancies.  Again, make sure you get transperancies made for your brand of printer.

Once you print on the transperancy, I suggest being extremely careful not to touch the image part of the print until you have laminated it.  I found that because of the textured surface, it is just about impossible to get finger prints off of the printed side of the sheet.  The backside can be cleaned off, but it is much easier to just keep it clear of fingerprints and dust.

Step 3:
Create the stencil.  The next step is going to be to paint the white outline on the back side of the transperancy.  To do this, you need to create a stencil.  I found that a thin piece of masonite wood worked quite well.  Masonite is a very dense composite fiber board.  I also tested out a simple paper stencil and one made of cardboard.  The paper one did not work at all because it did not stay flat when the paint was sprayed.  The air movement caused the paper to lift up.  The one made of cardboard worked, but the paint wicked up into the cardboard.  This ment that after one or two overlays, the paint started splotching onto the center part of the overlay.  I was able to scratch it off after it dried, but I don't think this would work well for more than a few overlays.    The key with the masonite is that the paint did not wick into it at all.  I suspect that glass, plexi-glass or metal would work as well if those are more handy materials for you.

Here you can see my stencil(well coated with white paint) sitting on top of an upside down printed transperancy.  The stencil is lined up and ready for paint.  Notice that I glued a block of wood on the back of the stencil so that after painting I can quickly lift the stencil up.  Also notice that although I have a bed of old newspaper to prevent the paint from coloring the basement floor, I placed a sheet of plain white paper between the transperancy and the paper.  Otherwise, the newspaper ink would rub off onto the transperancy and ruin it.  When you create your stencil, remember that it goes on the back side of transperancy.  This means that it is a mirror of the normal image.
Stencil


Step 4:
Paint the back of the overlay.  I found that I had the most luck by doing a couple things when painting.  First, apply pressure to the stencil to make sure it is fully pressed against the overlay.  I simply used a pole I pushed down on during the process.  Second, paint quickly, and lift up the stencil as soon as you are done.  If I left it on too long, the paint will wick in between the stencil and the transperancy.

Here is the result after painting, and then after removing the stencil.
Painted Overlay    Painted Overlay
Ideally, you would paint one, and allow all the paint on the stencil to dry before placing it on another transperancy and painting another.  However, this is impossible if you have to make a lot of overlays.  If you opt not to let the paint on the stencil dry, you need to be careful in a couple areas.  First, wipe any paint off the bottom of the stencil that leaked in.  Second, after 5 or 6, you will build up quite a layer of liquid paint on the stencil.  I found that I had to wipe off the thickest parts of the paint, especially near the edges.  If I didn't, this paint would leak down onto the transperancy.  Third, be very careful when you place the wet stencil on the next transperancy so that you don't smear paint onto the inner part of the overlay.

I found that while I was painting each transperancy every couple minutes, I had to wait until the paint on the stencil dried after painting about 30.  At that point the smears and leaking just gets too bad.  This point is also good to allow the paint to dry so that you can use a knife to cut off the thick layers of paint from the stencil.  The paint gets so thick, that the corners and edges of the stencil get "blurry".

  
Step 5:
Clean the overlay.  Once the paint on the back is completely dry, store it so that it will not get any dust on it.  Just before you laminate it you want to make extra sure that there is no dust or finger prints on it.  I found that it is very difficult to clean dust off the printed side of the transperancy.  The best way that I could find was an extremely light brushing with the side of my hand.  The back side is much easier and could be done with a lint free clean cloth.  If you have finger prints on the back side, a little pressure is required.  I found that this pressure actually caused a marking in the ink on the front, so I would recommend laminating the front side before applying the pressure.

This seems like an obvious step, but I cannot overstate it's importance.  It is very easy to overlook the smallest bit of dust.  Just a tiny bit will cause a large dimple in the laminating process which will look horrible.

Step 6:
Laminate the overlay.  This is one of the hardest parts to get good at.  A lot can go wrong at this stage.  Even after doing 50 overlays, I still lost 5 to 10% of my overlays at this point.

The self adhesive laminating sheets are full sheet clear stickers on a paper backing.  The best way to apply the lamination is to peal back an edge of the sheet, and slowly apply it at the same time as it comes of the backing.  If you peal the entire lamination off the backing and attempt to apply it, you will end up with bubbles, wrinkles or stretching.

First, peal back an edge of the sheet:
Peal back edge of sheet

The sheets I choose are quite a bit larger than the final overlay, so a good area of the sheet around the edges is discarded in the next step.  This means that finger prints on the edge of the laminating sheets is ok, but I would still recommend keeping the area as untouched as possible.

Next line up the laminating sheet so that you can "roll" it onto the overlay with the straight edge.  The sticky side should be down with the pealed off part of the paper backing resting on the overlay.  At this point it is probably useful to mention that you should be working on an extremly smooth flat hard table.  Ideally a glass table top.  I would not recommend a natural wood table surface as its grain is either not smooth enough, or if it is laquered smooth, the laquer might get marred from the pressure applied with the ruler.  It is useful to allow the laminating sheets to stick the overlay to the table as it helps hold it in place, so you obviously want a table you can peal it off of without damage to the table. 

When you line up the sheet, do not attempt to press it down onto the table or the overlay with your hands.  I found it worked best to use your hand to hold up the backing, then simply allow the sheet to rest evenly on the table at the edgeof the sheet.  This helps ensure that when you apply the sheet it will not bubble, wrinkle or stretch.  If you get it slightly kinked, you may manage to keep the wrinkles out, but in doing that you have stretched the lamination sheet.  When you pick up the overlay you will discover that it is now curled, and cannot be flattened.  It must be discarded and you will have to try again.  Note that because the laminating sheet is so much larger than the resulting overlay, it is actually not very important to line up the laminating sheet with the overlay.  The important part is to get the laminating sheet applied evenly. (even if it is slightly crooked compared to the overlay)

Lineing up the laminating sheet
Next use the straight edge to press the laminating sheet down onto the table.  I found it worked best to line it up about 1/2 inch into the laminating sheet from the edge.  This means that the first 1/2 inch may not be flat, but it is ok, as this section will be cut off and discarded.  The sheets I used are about 1 inch longer than the transperancy, so this allows you to actually press the laminating sheet onto the table instead of the transperancy.
Lining up the ruler
Next apply the laminating sheet.  This must be done with a smooth uniform stroke.  Use both hands to apply downward pressure on the ruler, and slowly slide the ruler forward.  If you stuck the leading edge of the laminating sheet to the table, then the overlay will stay put and will not slide away.  Make sure that you slike the ruler forward with a uniform forward pressure.  If at any point you stop, you will create a small wrinkle, which you will not be able to smooth out.  If you have setup the laminating sheet right, the paper backing will peal off automatically as the laminating sheet gets applied to the overlay.  Be careful to hold the ruler straight and apply even downward pressure across the entire length of it.  I found that about 10 pounds of downard pressure was required.  Further, as little forward pressure should be applied as possible.  If you apply to much, the laminating sheet will be stretched resulting in a curled overlay.  The picture below shows me using only one hand because I was taking this picture.  I highly recommend using both hands on the ruller.
Applying the laminating sheet
I mentioned above that the paper backing will peal off automatically.  This requires that there be nothing in the way on the table.  Another thing to note is that if you have done one side, and are doing the other side, the paper backing may get stuck on the last edge of the stickly lamination from the first side.  This happens near the end.  If you find this a problem, I recommend having someone help you and hold the other end of the paper backing up slightly.  Remember, do not peal the entire backing off.  Allow it to come off as the lamination is applied.

Next, while the overlay is still stuck to the table, you need to get the lamination fully applied to the transperancy.  Even with the downward pressure you applied to put on the lamination, I found that the sticky adhesive on the back of the lamination was not fully adheared to the transperancy.  This shows up as blurry areas.  To fully apply the lamination, run the ruler over the overlay applying a lot of pressure. This is where a strong ruler is required.  I found that I needed to apply probably 40 or 50 pounds of pressure to get all of the adhesive applied fully.  By doing this, you should see the blurry areas clear up.  The result should be crystal clear.  I found that it was best to draw the ruler back over the overlay applying pressure instead of pushing it forward.  This prevents it from digging in.  I am talking about moving it in the opposite direction used when first applying the lamination shown above.  If you use a straight edge with a sharp edge, applying this much pressure will cause it to dig into the overlay causing a dent, and possibly ripping the laminating sticker.  This is why a metal ruler will not work well.  If you did get some dust stuck in between, be very careful how you run the ruler over this area so that you don't rip the laminating sheet.  If you are careful, you can finish out the overlay, and perhaps the dust is small enough to ignore.

If you ended up with bubbles or wrinkles in the lamination process, it means that you did not line up the sheet evenly.  See the part above about allowing the laminating sheet to come to rest on the table instead of pressing it down with your fingers.

If the result is curled in the long direction, it means that you applied to much foward pressure causing the lamination to be stretched.  Once you finish applying the laminating sheet, it relaxes and contracts causing the curl.  You can try applying the lamination on the other side to "cancel" out the curl, but I would just give up and try again on a new one.

If the result is curled in the short direction, you probably did not line up the sheet quite evenly.  It is probably just slightly offset, and the downward pressure you applied prevented wrinkles or bubbles, but caused the sheet to be stretched horizontally causing the curl.  Unfortunitely this means another one down the drain.

Now, peal the overlay off your table, flip over, and repeat this process on the other side.

Over all, I hope you can see that this step is by far the hardest to master and is the most likely way to ruin an overlay.  If you are making a bunch of overlays, I would recommend making 10% more than you think you need to cover for mess ups.

Step 7:
Cut out the overlay.  Before cutting, I found that stacking up all my laminated overlays, and putting a pile of books on top for a day or so helped take out any slight curls in the overlays. 

Actually cutting out the overlay is as you would expect.  The paper cutter comes in handy for cutting the long straight edges, but you will need to cut the corners and the finger hole with a pair of scissors.  The cutting takes a bit more pressure than normal paper because you are cutting through the plastic transperancy, the layer of paint and both laminating sheets, so you might want to give your hands a break after cutting out a dozen or two.  I would recommend a sturdy sharp paper cutter and scissors because you need to get through all three layers without stretching them.  If you don't cut through all three in the same line, the laminating sheet could stick off the edge, and be prone to pealing later in life.

When you cut them out, make sure you are cutting the proper size.  If you cut the overlay to small, it will fall off of the vectrex.  Slightly to large, and you will have a very hard time cutting just a sliver off of it.

Step 8:
Put the overlay in a protective bag.  I liked to give the result a good polishing with a clean lint free piece of cloth to remove finger prints before putting it in the protective bag.  Simply fold over the plastic bag, and tape shut with a small piece of sticky tape.

Result
Voila! and you are done!

Comments:
Overall, expect an overlay will take about 20 to 30 minutes to hand make(assuming that you have assembly lined the process).  I can tell you that this gets quite tiring after a while, but the result is worth it!

Now that I've told you how I made mine, and how you can make your own, I ask that any other homebrewers use this method(or create an even better one) and release overlays with your game.  Overlays add so much to the fun of the Vectrex!

Long live the Vectrex!

Ideas:
I had a couple ideas that someone could experiment with that may make the result look better
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