Ultimate Playfield Restoration Guide
This is part two of a six part series on doing a high-end playfield restoration. This article covers resolving insert problems. For an overview of the process see the Ultimate Playfield Restoration Guide.
- Removing Inserts
- Sanding Inserts
- Cleaning Insert Hole
- Installing Inserts
- Raising Inserts
- Insert Decals
- Questions and Answers
Before we pull an insert out from the playfield, we want to be sure it does not lift any of the surrounding artwork. Most Williams games have no, or almost no clear coat (whenever someone talks about wanting Stern to have "Williams quality", all the ops laugh).
Just to be safe, run a brand new X-Acto blade around the insert (see Image 1). If it's a new Stern game, or if it has been clear coated, really make sure you have cut the insert free of the surrounding clear coat. Next after cutting through any clear coat, it is time to remove the damaged/faded insert.
- Find a wrench socket that just fits into the insert hole on the bottom of the playfield. On strange inserts like a chevron arrowhead, I use a small nut driver.
- Take a hair dryer, set it on high and warm both sides of the insert. (I use a heat gun, but I don't want any beginners thinking that this is a good way to learn - too risky until you have a feel for this stuff).
- While keeping your hand on the face of insert to control its release, push the insert out from the bottom of the playfield. It does not take much pressure at all. On Williams games, you might get the feeling that the insert "wants" to come out - its that easy.
Many people don't know how playfields are manufactured, so they don't understand that you can't just put a new insert in the holes without working them first.
- The sheet of plywood is CNC routed with all the holes.
- The inserts are glued in by a Pick N Place machine (see video at bottom of article).
- The entire playfield gets run through a drum sander. The drum sander sands the wood and the inserts all down to one level.
- The wood is coated with sealer and it goes to the silk screen to print the graphics.
So, brand new inserts are not flat (see Image 2). They don't have to be, because they get sanded flat after installation in the playfield.
We don't have the luxury of sanding the entire playfield (unless we are installing a printed overlay over the entire surface), so we have to flatten the inserts first.
To get the inserts flat, you start with 100 grit sandpaper. Place the sandpaper face up on your table saw (or any other really flat surface), and move the insert around in a circular motion. Apply even pressure, checking your work often.
You don't want to take too much off, because thin inserts are more likely to crack. Next sand with 220 grit, and finally 500 grit. Do not polish further. You will see why in the clear coating section of this guide.
The old playfield glue can be epoxy or a sticky mastic of some sort. You want to clean it all out so the wood can accept the new glue (see Image 3). The sticky mastic stuff does not readily take to other glues, so be extra careful if you encounter it.
If the soft mastic is hard to remove, use the Burr tool with your Dremel (see Image 4). Don't enlarge the hole by removing wood, just spin out the mastic.
As you have probably noticed, even brand new playfields have problems with inserts lifting up. Wood contracts and expands at different rates than does the plastic insert. We sure don't want to spend all this time restoring a playfield and have the inserts rise up again and ruin our clear coat.
We want to glue in the new insert (or reseat an old one) and never have to do it again. That means we have to do a better job than the manufacturer did.
If you have ever put a glob of epoxy on an insert, you may have noticed that you can chip it off after it has dried. Obviously, this is not an acceptable bond for something we never want to do again. We need to give the epoxy some "tooth", so we sand the edge of the insert with 100 grit sandpaper (see Image 5).
This is where you start to separate the boys from the men in playfield restoration. Even sanding the edge of the insert is not enough. The final step is to prime the plastic with 3M Plastic Primer (see Image 6). It goes on thin like water and dries in a few seconds.
Now when you apply the epoxy, you can't chip it off.
Clear two-part epoxy is the glue of choice here. We know it sticks to our primed plastic, we know it sticks to wood. Any glue you can easily chip off of an old sacrifice insert like wood glue, Gorilla Glue or silicone is obviously not going to give us the permanent bond we require.
I use Two Heads epoxy, but you can use just about any brand. One of my favorite restorers has been using the Harbor Freight $1.50 stuff for years with perfect results. Pick a brand with honey-like consistency, you don't want a big mess dripping out the bottom of the playfield.
Always apply the glue from the bottom of the playfield (see Image 7). This way you won't drip on the painted surface and the "squeeze out" will head towards the underside.
Never apply glue to the insert itself, or it will squeeze out on top of the playfield. If you do somehow get glue on the playfield surface, wipe quickly with a rag lightly dampened with acetone.
Use an "acid brush" to apply the glue (you can get a bag of them for $5 at your local plumbing store or Harbor Freight). Epoxy dries quickly, so you will throw a bunch away as you work. Don't bother trying to clean or save them.
If you are a beginner, glue up to maybe 2 inserts at a time. Don't get too far ahead of yourself, once the glue hits its "work time" it starts to set up fast!
Sometimes you find that an insert has "a mind of its own" and won't stay down for the epoxy to set. There could be some tension in the wood (maybe the reason the insert popped out in the first place). To fix this, use a 12" C-clamp ($9 at Harbor Freight) to hold it from rising above the playfield surface (see Image 8).
Knock the edges off of 2 blocks of good quality (flat) plywood and clamp with 2 pieces of wax paper (in case any glue squeezes out). Don't forget the wax paper, you won't be happy if you glue a piece of wood to the playfield.
Sometimes you hear someone tell you to just use a piece of wood with a hammer and bash the inserts back down level with the playfield. The problem is that although they will stay down for awhile, whatever forces that were in the wood that ejected them in the first place are still there, and they tend to pop up again.
You can heat inserts with a heat gun and press them down with the 12" C-clamp - this tends to last longer than just hitting them, but still they tend to pop back up. Once you have a nice clear coat on the playfield, you don't want to ever mess with the inserts again, so just reglue them the correct way.
There of course will be inserts that you will not need to replace or reseat. After 20 or so years, you would think that if they were going to move, they would have already moved, and certainly there is some truth to this.
But a new clear coat is going to put new tension on the playfield that was never there before, so usually you will want to apply some glue to the back lip of those inserts. I know, it's not as good as roughing them up and using plastic primer, but it is better than a surprise 6 months down the road.
Sometimes you find that inserts have sunk below the playfield surface. Not cupped, but actually fallen in. Cupped inserts can simply be filled with clear coat, but if you can see the wood beneath the playfield around the edges, you need to raise it up.
Heat the insert from above and below with a hair dryer. Keep one hand on the face of the playfield to control the insert, as you push the insert from behind with the largest socket from a wrench set that will fit in the hole. You may have to reheat while you work.
If the insert is really loose, and you can easily remove it, do so (rough up the side edges with coarse sandpaper, prime with plastic primer and re-glue with epoxy).
If the insert is really tight, then just level it with the face of the playfield and re-glue the entire insert perimeter from the back of the playfield with epoxy. Don't spare the epoxy, better to have a heavy coat that no ones sees from the back, than to have the insert move around in the future.
This section we will discuss applying Water Slide Decals (WSD) over inserts.
- Laser print or silkscreen WSD's . Regular ink jet printer's inks fade quickly.
- Use clear WSD's on most inserts. If the insert has white printing on it, use white WSD's or print with an ALPS printer on clear decals (the only printer I know of that prints with white ink is the ALPS. It can even print metallic gold and silver .).
- Most hobby shops have great printers and will gladly charge you to print your decals.
- Turn the toner darkness up all the way on your laser printer to get a nice dark image. Turn off any "toner saver" or "economy" modes. There is no room for economy when restoring playfields
- Make sure you have your first coat of clear on the playfield before installing WSD's. You don't want a different tension above the decal than below it; or you might get ghosting (decal ghosting is where the decal lifts from the insert).
- Since you need to clear coat over the decals, sand the whole playfield down to 1000 grit so the next layer of clear has some "tooth" to adhere to. Since you can't sand the decals, you need to do this BEFORE you install them.
- Refer to this part of the article series to see how we scan and acquire the art and type font.
Supplies you are going to need (see Image 9).
- Shallow dish of clean water. Use just regular tap water. Neither cold nor warm water is required.
- Decal Setting solution. I know someone is going to chime in and say they don't use Decal Set, but we are going to restore a playfield worth $$$$, so a $3 bottle of solution is not going to kill the budget. If you are going to start restoring playfields, get in the habit of doing things right. Decal Set smells like Acetic acid, but I don't know anyone who has ever figured out what it is exactly. It softens the decal so wrinkles come right out and helps with adhesion.
- Decals. Although the instinctual reaction is to reach for your X-Acto knife, cut decals out with sharp scissors. Razors tend to leave an edge that sticks up and makes it harder to release the decal from the backing paper.
- Small Acid Brush. Any small brush can be used to apply the Decal Set on the playfield.
- Soft, lint free cloth. Use this to apply the decals.
Soak the decal for about 45 seconds in the water (see Image 10). The time does not have to be exactly 45 seconds. You will know the decal is ready when it easily slides off the backing paper between your thumb and forefinger.
Long or large decals tend to curl as the water saturates the paper backing quicker than the decal itself. Soak these decals face down to prevent this curling.
Assuming you already blew all the dust off of the playfield before you started, brush some Decal Setting Solution over the target area.
Start with the inserts in the center of the playfield and work your way out the edge. This way you won't mess up the decals you already set.
Now start sliding the decal from the backing paper. Don't touch the back of the decal where the adhesive is! You could leave a fingerprint or introduce dust. Hold one side of the decal against the playfield with your finger, then slide away the backing paper (see Image 11).
A good trick is use a playfield rotisserie and lay a 4 foot long florescent lamp on the floor, directing it's light upwards to illuminate the inserts. Rotisserie or not, you will probably need a small flashlight to perfectly align the decal (see Image 12).
Often, the black key-lining of the playfield is poorly aligned with the inserts. Do the best you can, but be prepared to fudge a little bit to make it look right.
Once you get the alignment correct, it's time to "set" the decal. Anchor the decal at one edge with your thumb to keep it from moving around. Using your lint free cloth soaked in Decal Setting Solution, press out the excess water and air from under the decal.
Once you have 95% of the decal pressed out, move your thumb to the pressed side, and wipe down where your thumb was originally (see Image 13).
If you have ever tinted the windows in your auto, you will instantly know what to do on the playfield. Push bubbles and wrinkles out to the edges until the entire decal is set (see Image 14).
If you went to fast and have a "permanent" wrinkle or notice a miss-alignment, flood the decal with Decal Set, and carefully work it out by pressing and wiping.
Let your decals dry overnight and you are ready for clear coat.
Two-part auto clear is "hot", meaning that it has very active solvents that will melt your fragile decals if you are not careful. If this is your first time spraying clear, practice on some decal scrap stuck to a beer can or piece of sheet metal. Get the feel for how much clear melts the decals on some scrap rather than your precious playfield. When I say melt, I mean destroyed; the effect is not subtle.
Spray your first coat as dry as you can. Almost dust over the decals. Ten minutes latter, give another very, very light coat. Ten minutes after that, you can finally give a normal, light coat of clear.
Now your decals are protected. You can make any other last minute painting touch-ups you found, or go ahead and finish clear coating the playfield (see Image 15).
Note: If you purchased the insert decals make sure they can have automotive clear coat applied over them before using them.
The manufacturer of the decal should be able to tell you that. If info is not available, use some scrap of the sticker (like the model number or color bars), stick it to a piece of metal and clear it to see what happens. Make a scan of the decal before you start. That way if hell breaks loose, you can print another on more suitable stock.
Question: I'm having a hard time finding the 3m plastic primer for reseating the inserts. Every place I found wants to sell me a case of 12. Where can you find this stuff ? Is there another product that is comparable if I cannot locate the 3m brand?
Answer: Find the local plastic dealer that sells the bulletproof plastic to all the gas stations and pizza joints. Many cities have the chain of "AIN" plastic stores. It is also available at General Rubber Plastics.
Question: Vid, how would you handle badly cupped inserts on an otherwise great condition C37 playfield? Is there a solution that doesn't change the rest of the playfield too much?
Answer: Un-jeweled inserts often cup if they are larger in diameter than 1/2" or so. Scuff up the insert with 600 grit paper (so the clear can have some "tooth" to grip to). Perfectly level the playfield on your work bench. Mix up some 2 part auto clear with the fastest hardener you have. If you use slow setting catalyst/ hardener, you run the risk of it attacking the the old varnish and creating little whitish spots.
Using a glass eyedropper, drip into the cupped insert until it is leveled off. If you over fill, sand before the clear gets too hard. Wipe up drips quickly with lacquer thinner. Don't let the thinner melt the existing clear or ink.