Quoted from John_I:
I posted some words of caution and tips in the other thread and figured I should post them here too:
I would be concerned about the long term outcome of this experiment. In particular I'm worried that eventually the glue would weaken and the protector would pucker/lift upward in the middle of the playfield. Poly-carbonate expands at a much greater rate than wood when heated.
I made my own protector for a Bally Quarterback. Instead of cutting around all of the playfield posts like existing protectors, I used small holes that went underneath all of the posts and reinstalled the posts on top of the protector. I quickly learned why the protectors were designed to go around all of the posts: to allow for expansion. Within minutes of turning the game on, the protector lifted away from the playfield in the middle by at least a quarter inch! This wildly changed the direction the ball moved in during the game. After turning the game off and letting it cool, the protector sat back down as flat as could be.
I thought about gluing it down, but my solution for this problem was to make sure the game/playfield never heated up. Obviously the first step was to replace every bulb in the entire machine with single LED bulbs. Next I noticed that there was a bridge rectifier installed on the bottom of the playfield using the playfield as a heat sink. I unscrewed the rectifier and attached it to a metal heatsink installed on a plastic standoff. After that I unscrewed all of the relays attached to the bottom of the playfield and installed them on plastic standoffs. Finally I installed a forced air cooling system with two 64CFM fans blowing in through the bottom of the machine where the coin box once was. The air blows directly toward the flippers then passes along the playfield and out the top of the backbox. One entrance, one exit. I installed temp probes in the machine and it doesn't heat up more than one degree even after hours of play! The end result is the playfield protector sits flat and plays amazing no matter how long the game is turned on.
My recommendation for anyone who installs this product is to do whatever possible to remove heat from the game and in particular insulate the playfield from heat producing components and boards. I might have gone overboard with the fans, but better safe than sorry. As long as the game does not heat up much during play, there should be nothing to worry about. I look forward to someday trying one of these on one of my machines.
Thank you for posting your concerns and experience! I have a couple of differences to note, and some details about the adhesive.
First, the testing on this product started over of a year ago. As noted in previous posts (I know there have been a lot of them)... The first "acceptable" Hardtop was installed on my personal Space Shuttle approximately 8 months ago now. There have since been 2 more installed on other games. First was another Space Shuttle in my friend's game and then another in the "official" beta test that I was willing to proceed with after the positive results experienced with the first two in my "inner circle". It was only then that I started making our product idea public by posting about our project.
As a note... There were 4 versions prior that had issues as we tested these. Most dealing with missing holes and adhesive that needed to be changed in the die file.
FYI... to date... "ZERO" issues.. "ZERO" buckling on what we are deeming "ready"
While familiar with expansion and contraction rate differences between wood and Polycarbonate (only one of 2 materials used on the Hardtop) ... it is true I have not conducted actual tests comparing the specific wood product used for playfields to the Hardtop.
A behind the curtain disclosure:... Our ORIGINAL idea for the product (Like I said, over a year ago) would have been ridiculously cool... but it just was not feasible. I know because I tried it, and had the help of some really knowledgable folks in the polymer business helping me. The idea was to create the very product you see that FLOATS over the existing playfield.... no adhesive. I made several, tried them... and while they "could" work, it would have been a disaster trying to make sure each collector installs with NO PINCH POINTS for buckling. It was unwieldy even for us... so we scrapped the idea. With that element gone (of no adhesive)... gone was the marketing claim that these can be purchased to preserve existing,savable, original fields. BUMMER!
However, I have spent 23 years in the commercial/industrial printing/fabricating world and have learned (sometimes the hard way) what works and what does not work. So, we moved on by developing an idea to use an adhesive product that must be VERY robust. We know where to look, and what to use for different applications. The adhesive is a 3M product that is the same used to hold together things outdoors (think temp. changes) on all sorts of materials. This left a market for us to explore that would include "roached" playfields that really had little value and poor play. With this product ... it would (as you have seen in the videos) resurrect a junk field back into an attractive, usable playing surface. As a result of my testing, it appears as though the product delivers just that.
One of my concerns are the durability of the surface itself. Scratching resistance. Polycarbonate on it's own is a poor choice for a playing surface. It's too soft, and easily scratched. So, I set out with my trusty vendor list of plastics professionals and quickly weeded out the folks who did not show the interest, or simply lacked the knowledge to help. I wound up with a hard coating applied to our .030" material that is NOT commercially available. This hard coating is usually on airplane canopies, tall building windows, and other exterior... industrial applications where scratching is to be avoided at high cost. The manufacturer is making this material for me in small runs... as long as I wait for the lengthy lead time.... for a price! I still was not satisfied in spite of my "non scientific" testing with a silver ball at my shop, and with actual testing in my game. I wanted DIRECT comparisons to our product as compared to how games are made right now... and restored ... clear coat! I can honestly say now, that my product withstands swirl and scratching better than clear coat. I have the data in hand from Israel, where the ATSM testing was conducted. I sent actual wood with the same coatings over there. No, the data did not already exist, as the plastics world and the clear coat world do not normally test the same way. Therefore no apples to apples existed.
It is true that I cannot report or guarantee anyone that the adhesive will not "eventually" fail years down the road. As did the fields themselves in the first place! Nothing is forever. What I can say in regard to temperature change is that one of the test Shuttle games is in an unheated garage in Ohio... where we turn on the heat and consume Beer and play games after the temp reaches 60F +... no issues. I can also report that the other game is in my basement that normally is 55-60 degrees until I turn on the gas fireplace... and consume beer. No issues. Fairly decent temperature changes, now that is not to say (to your point) that some games might have hot surfaces that occur that could create problems! We will have to address. We are going to prototype EACH TITLE with collectors (some of which I am sure are reading this) and play them for a while and leave them on for hours and do the things we do with temperature before we just go shipping out tons of these. Actually, while testing.. said collectors may also consume beer. Well, except one who may have a glass of homemade wine.... ANYWAY... I get your concerns, have delt with them on the one titles we have developed and will be shooting the issues out of the air as they arise when we develop COMET, PHARAOH, WIZARD and FUTURE SPA for starters. In all, we have 32 (I think) now on the list to do.
The adhesive life/quality is greatly effected by PREPARATION. Our Shuttle beta tester wrote the book via Youtube how to do it right!
Adhesive effective bonding temperature range: -40F to 400F
Exterior grade and highly effective even in high humidity
Resistant to gasoline, oil, MEK and much more
Untechnical term for adhesive: Badass
We ask for patience as we complete our due diligence for each title. Space Shuttle... I am really comfortable with. Time to move on and doll up more games!
In the end, is this a new playfield? No, nor is it being sold as that. It is a "next best thing" to NOTHING being made, and we have certainly worked hard to develop an exciting option for lots of folks and THOUSANDS of ugly playfields. We are excited, but do not in anyway intend to over sell what this product is. I really do think you will all like it
Happy Friday all!