I forget what year it was, but I was at Disneyland sometime in the early to mid 80's, probably 1983 or 1984.  It was summertime and I was there with several friends one day.  Naturally, we had to make our visit to the Starcade as always.  This time was a little different, however.  As soon as I made my way up to the second floor, I noticed a crapload of Environmental DoT's lined up along the wall.  Man, what a sight to see.  I wish I had taken a few pictures to share.  I'm sure many of you recall the spectacle if you ever went to D-land in the 80's.  Anyhow, I fell in love with the game instantly!   Not only did the game look cool, but it was an interesting game to play as well.  The one single complaint I had was the spinner.  Well, that and the ever so flimsy joystick they used, but I'll save that for another BLOG.  Even as a brand spankin' new game, the thing had problems with their poorly designed spinner.  Given the fact that this game was an MCR based machine and the terrible spinner control, I knew I would be seeing these in the shop eventually.  Here begins the project BLOG. 

Boy, was I right.  By the time I had left the arcade repair business, I had seen more repairs to Discs of Tron games than I care to mention, although it was a rare sight to see the Environmental version at the shop.  I'd say that the majority of the repairs centered around the "sandwich" boardset, namely the CPU board.  Next was the power supply board.  Of the controller issues, all problems were either the failing joystick grips, the centering grommet or the spinner.  When the spinner was failing, it was usually the same problems: dead opto board or binding spin action.  For this project BLOG, I will be focusing on the spinner for the most part, maybe with an occasional sidetrack or two.  

Pictured to the left is an OEM spinner made by Bally/Midway.  I snagged this photo off of a recent ebay auction that I had planned to bid on but my bidding software crapped out on me and didn't place the bid.  That's what I get for trusting it.  This spinner, although an original (and interesting) concept, has three significant mechanical design flaws which I will address.  The first issue is the single point of contact for roational/spinning motion.  This is a BIG problem.  An enclosed cage would have been so much better.  The second issue is the fact that a big bushing was used instead of ball bearings or TWO bushings (one on top, one on bottom).  The third issue is the push/pull mechanism which is a shaft inside of a shaft.  While the idea itself is sound, the way it was implemented was definitely done on the cheap.  Because of this, there's binding on the push/pull and a lot of play in the spin action.  Simply put, the control feels rickety at best.  Here's where I come in and do an overhaul on the design to make it all better.

Construction Progress

	01/17/07:  This project was officially started after a few other projects had already begun and after the Major Havoc project had been completed.  I began this project by digging up a copy of a bally/midway manual which depicted a blow up diagram of the spinner.  Already aware of the issues with the controller, all I required the paperwork for was to obtain some basic information on the controller, including the optical board (which, by the way, will be reproduced to spec. as well) and mounting hole spacing/pattern.
	01/19/07:  The first thing I did was redesign the frame.  Instead of using the same design as the OEM, I went for an enclosed "cage" frame so I could stabilize the spinner shaft from two points of contact (upper and lower).  This is a very critical issue which was overlooked by the Bally/Midway engineers for some reason, most likely a result of cost reduction.  Without the stability afforded by two points of contact along the length of the shaft, the actual rotational spin of the device is compromised and degraded by design.  Add to that the use of the single bushing and what you have is a spinner made to barely work at best, miserably fail at worst.
	01/22/07:  Next, I redesigned the outer shaft (which mounts to the encoder wheel) to connect at both contact points at opposite ends of the cage frame.  In simple terms, I lengthened the outer shaft so it would touch the top and bottom of the frame.  Interestingly enough, the outer shaft actually rides along the inner diameter of the bearings I am about to discuss install into the cage frame.
	02/18/07:  I then modified the cage frame to accept two type R6 ball bearings (one on the upper and one on the lower half of the frame) using pillow blocks (similar to what I used on the Tempest spinner).  I considered pressing the bearings directly into the frame but then I realized it would negatively affect the ability of techs/collectors to remove/replace the bearings with ease.  I'm not one to build an item on the cheap, so the added cost of designing/constructing this spinner the right way simply cannot be avoided.
	02/24/07:  With the cage frame and outer shaft components prepped, I began a partial build to verify that the parts were manufactured to spec by the use of standard form/function testing (ie: slap it together and see if it works).  From this point, I checked and double checked to make sure the "outer" shaft made contact correctly and spun freely, which it did by the way.  Two thumbs up.
	02/29/07:  The next step was to modify the outer shaft to accept an inner shaft with tight enough  tolerances to alleviate any unnecessary play in the rotational motion (ie: spin action).  In other words, when the spinner knob is turned in either direction, the inner spin shaft should make positive contact with the outer encoder wheel shaft immediately so as not to appear sluggish on the responsiveness during gameplay.  This was always a very serious issue with the OEM design.  The "play" is near unbearable to deal with in my opinion.  So, this design flaw was to be overcome during this step.  I had considered using a one-piece keyed shaft, but CNC machine time would be very excessive to produce such a part.  I also considered using a simple spring pin as used in the OEM design, but with tighter tolerances.  I finally settled on using a small custom made key which attaches to the inner shaft and rides along a slot in the outer shaft.  This not only greatly reduces the amount of rotational play, but also strengthens the overall stability of the inner/outer shaft dynamic.
	03/07/07:  I am working on the push/pull aspect of the design.  I considered using snap-action switches for this aspect, but ultimately decided to go with leaf switches similar to the OEM design.  Why?  Because the feel of leaf switches is appealing, opposed to the clickity-click of those snap-actions.  Besides, this is one portion of the original design that was not in need of change.  However, given the overall changes I've made thus far, I need to come up with an acceptable method to implement this feature correctly.  I'll need to add a small sub-assembly to the bottom of the spinner in the form of a bracket.  Luckily, I left enough length on the original inner shaft to accomodate this added feature, so it should not be an issue.
	03/28/07:  The push/pull sub assembly has been added and works as expected.  To the left, you can see the completed prototype unit as-is.  Overall, this design is about ready to put into production.  I'm now working on the design of the opto board(s).  I'm working on a spec. opto board which will function with an original Discs of Tron and an alternate opto board for use with standard inputs for MAME users.  Unfortunately, I will not be designing a USB/PS2 adaptor.

Updates

03/29/07 - After working on this project for awhile, I realized that I need an OEM DoT push/pull spinner to use for several measurements to make certain that I get the flywheel weight as close as possible to the original and to verify the mounting hole spacing and pattern.  Additionally, I need the controller fully intact so I can get my mittens on an OEM opto board to repro.  This project is on hold until which time I have an OEM controller.  I'd be happy to buy, trade or haggle for one of these.  Anyone??

04/30/07 - Still waiting on an OEM controller.  I JUST missed bidding on the one on Ebay.  For some reason, my snipe software didn't place the bid and I lost my opportunity.  Oh well.  Anyone out there have a DoT spinner I could at least borrow for a few weeks?

05/07/07 - This project BLOG has just been converted  from notes and pics taken awhile back and added to the website for reference.  This has been an interesting project from the start.  The redesign on the frame was absolutely necessary and will make the controller not only more stable but much better to use during gameplay.  Stay tuned for new developments.

05/25/07 - At this point, the project is on hold pending the acquisition of an OEM DOT spinner.

06/01/07 - I've made some progress with the project, without the luxury of the desired OEM spinner.  To date, I've been able to reproduce the knob and I've begun the process of reproducing the encoder board as well.  These are still in prototype stage, but I expect to have both items into production in the next few months.  These are both parts I do have originals of, so I decided to focus on what I could work on instead of waiting.

06/16/07 - I'd like to note that I've expanded this project considerably.  Not only am I working on the push/pull spinner, but also the joystick and the whole Environmental DOT cabinet as well.  I have recently expanded my capabilities with regard to manufacturing options, so the wood cabinet is a piece of cake as well as the plastic handle on the joystick.  I will need an OEM joystick to work from, however.  I have some leads on complete cabinets, let's see if any of them pan out.  Stay tuned!

06/29/07 - The production run on the knobs has been started.  I expect them to be completed within the first week of July.

07/03/07 - The production run on the knobs has been completed.  They're made from machined 6061 aluminum and hard anodized black.  They look beautiful!  

07/14/07 - After successful testing of the prototype encoder boards, I have put them into full production and they should be completed sometime soon.

07/28/07 - The PCB's for the encoder boards have been completed.  Assembly has now commenced.  

08/22/07 - The encoder boards for the spinner have been completed and are ready for shipment. 

09/17/07 - I had a lead on an OEM spinner, but missed it....again.  Does anyone have a spinner they can let me borrow for a few weeks?  I'm tired of missing out on all the deals! 

10/07/07 - I've taken receipt of the full allotment of R6 bearings for this project.  Good news!  Stay tuned for more info.

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