How to replace the protective DMD plastic on WPC95

The past years I always heard from people that replacing a damaged plastic that's in front of the DMD on WPC-95 games was very difficult or impossible to do.. I never had to try it myself, so never investigated how difficult it was.
The whole new plastic speaker grill assembly is also pretty hard to fine and expensive, so fixing a scratch in the clear plexi can be an expensive job..

Recently an operator I know bought a Junk Yard with a damaged DMD cover and I said I'd have a look at it.. It couldn't be that hard, could it ?

There's one difficult thing everyone who tried and complains about encounters: the plastic is held by metal rings that are pressed over plastic knobs. You have to be careful not to damage the black plastic knobs, as they are part of the front piece.. you can't just put some new screws in the black plastic as that would really damage it.
And further you have to be able to remove the metal rings without damaging them, or finding new ones so you can again secure the new protective cover on the black plastic knobs.

So, is it really such an impossible task as you hear on the web ?
No, not at all.. at least that's what I think of it..

As said above, the difficult part is to remove the metal rings without damaging everything too much.

DO NOT CUT THE BLACK KNOBS !!!
I've heard of people cutting the top off so they could remove the metal washer, and then weren't able to secure the new plastic. You really need to keep these black knobs intact !

The trick to removing the metal washers is shown in the picture below: use 2 flathead screwdrivers and gently work them upwards.. Try to keep them in one piece, but most important try not to damage the black plastic.

If the metal rings are too misformed when you have them off, then make them flat again using pliers or a vise.

Some rings were really very difficult to remove, so using side cutters I cut the ring. That way it was easy to remove but could still be used to put it back on later.

You also don't have to remove all metal rings - you can leave one long row (top or bottom, it's your choice) on and pull the plastic out sideways. Don't make the job harder for yourself then you have to. (in the picture below I already removed too many)

Once you have removed enough metal washers, the damaged plastic slides out. Trace its shape on a new piece of plexi or lexan and cut out the shape. Try to match the original size as good as possible, but as you don't see the edges of the plastic from the front, they don't have to match perfectly. Just see if it fits well and the holes where the metal rings go aren't too large.
Do try to match the thickness of the plastic, a much thicker or thinner plexi will not fit well.

In the picture above you see at the top the old plastic, at the bottom the new one I cut out (blue protective plastic still on).

Next step: install the new plastic cover you made and put the metal washers back on. Even the rings you had to cut (see picture, most on top I had cut) will still have enough force to keep the plastic in its place when you put them on.

If these cut rings will be strong enough will mainly depend if the game will be in home use or go out on location again.
In home use it should be ok this way. The plastic will stay in place and you can push quite hard on it before it moves backwards. Don't be afraid the plastic will fall out when you ever move the game. And as it's a home location, it shouldn't get much abuse.

If you're an operator and the game has to go back on location you probably don't want to take any risk. I suggest you secure the metal washers you have doubt about, using a glue gun. You could also use some kind of 2-component glue/epoxy but that can't be removed anymore in the future.. if you ever have to replace the plastic again you won't be able to do so without damaging the black plastic knobs.
Using a hot glue gun, the metal rings will also be secured, and using heat you'll be able to remove the hot glue without melting the plastic, so you can do a new repair in the future if necessary..

Here's how the front side looks. A brand new clear DMD protective plastic installed..