Air Hockey Build

[ids]

So... my mame cab is almost done, with no post about it - it's just a plane jane UAII, CP still a WIP, but here I go....

I got the bug to build an Air Hockey table.  After much googling and searching this forum, I'm rather empty handed at the  moment.  A lot of broken links, and not much to go on.  I just picked up what I am hoping is a decent blower - very similar to this this, but takes 115V (with related change in Amps).  Same mfr, same motor model #.  It's used, from a local "surplus" shop - runs fine.  Based on the specs of the similar device, guessing it's 350CFM.  I can't claim to know what is meant by the pressure in water thing.

This build is not a huge priority, and will probably take some time.  No overall design, not certain the hole size to use: 1/32, 1/16, etc.  Not sure how close together to place the holes.  Not sure how much pressure my blower can produce.  I have seen some things on the net w.r.t. hole size and spacing...it's all different.

At the moment, I'm thinking 8'x4' table, probably a bit less play area as the sides will probably overlap it a bit.  Maybe melamine or formica for the top play surface.  Yes, I know, at least 4000 holes to be drilled.  It's a fact I accepted before buying the blower.

Bottom line, this is a place-holder for building an air hockey table.  My hope is that others out there can contribute somehow.

I know I am submitting myself to an opinionated bunch, but there is also a lot of knowledge out there.  I'll post progress as it happens, and I hope help comes in before costly (time or money) mistakes.

Thanks all, in advance

[thatpurplestuff]

I've got a roughly 7.5' long air hockey table that I bought from Costco about 4 years ago.  It was only about $250 so it is definitely on the low end of the spectrum in terms of quality, but if I can be of any help in terms of measurements or anything just let me know.  One random quirk about my table that is a HUGE drawback is that the 2 blowers are only strong enough to keep the smaller 2.5" pucks afloat.  I didn't think that it would be an issue, but smaller pucks tend to get airborn MUCH more frequently than the larger pucks.  The problem is bad enough to where we try to only play with triangle shaped pucks because they are the only ones that stay on the table for any length of time.

If I were you the one thing I would make sure of is that your blower is powerful enough to keep the bigger pucks afloat.  I'm attaching a picture of one of the two blowers on my machine, so it may give you an idea as to how much power you'll need.  Anyway, seems like a big undertaking but I'm curious to see how this goes.  Good luck!

[ids]

Thanks.

From my research, that type of blower is used on lower end models, and just doesn't have enough power.

The one I picked up is the squirrel cage type:


Since I got it so cheap, I'm thinking if it doesn't have enough power, I'll just have to pony up and get a good one ($300+).

Current plan:

• get over to an "arcade" with a real commercial machine, measure hole size and distance between.
• use formica for the top, glued to ply/mdf maybe 3/4"

Apart from all the holes, I think this will be an "easy" build - it's just a box after all.

[javeryh]

Sounds challenging to me - how will you get the airflow to be even across the entire table?  I'll be following this build - I'm really interested.

[ids]

My hope is that the blower will be able to fill the "plenum" and thereby provide even airflow everywhere.  Seems to me like there is a balancing act; the blower is low pressure but high volume (~350cfm), need to make sure holes are not so big that all the pressure escapes from just a few, and not so small so as to defeat the blowers abilities to build pressure, etc.  I'm no physics major, so my plan is to leverage specs from commercial machines.

One thought, which comes from something I saw...somewhere... ensure holes directly above blower don't get too much flow:


And thanks to a member here, I got this Popular Mechanics link, fwiw

And fyi, the blower I have is surprisingly quiet - noise was something I was afraid of earlier, with thoughts of using something like a shopvac for airflow.

[TheGameFan]

Maybe try smaller holes near the blower and larger holes farther away?

[ids]

Edit: Puck is actually 3-1/4", making this mostly irrelevant.  There will be at least 8 holes under the puck.

That's an interesting idea.  Without any physics, tho, I'm scared.  It's an awful lot of holes - not easy to try something, then start again if it doesn't work out well.  I suppose I could start small, then expand.  It's a different challenge to shrink a hole once drilled.  Perhaps start small, and if some areas need more lift, either direct air underneath, or up-size the hole.

Playing with the idea of a 3" puck, 1/16" holes at 1" spacing, I came up with the following.

Worst case scenario (in terms of lift) 4 air holes pushing it up:


Typical (guessing) 7 holes:


Best case scenario, 8 holes:


The puck is thicker around the sides, giving itself an air-pocket of sorts.
And it will be moving.
(trying to convince myself it will all work out)

[Shortbus]

awesome....along with skeeball and slot machine, add this to my list of things i wanna build....look forward to following this thread!

[ids]

Skeeball - what an awesome idea!  Don't know why I've never thought of that one.  Will put it on my list, right under shuffleboard table.

[Shortbus]

Skeeball - what an awesome idea!  Don't know why I've never thought of that one.  Will put it on my list, right under shuffleboard table.

check out thatpurplestuff, he's replied to this thread, he did a great job, still in the works if last time i checked....

not enough hours in the day....

[Silas (son of Silas)]

That Popular Mechanics link was an interesting read, but the story photo on second glance looks a bit sinister. It's as though dad's been playing too hard and has had a stabbing pain in his chest, lets go of his goalie mallet and drops his hand to his knee as he bends over. Meanwhile blond daughter is calling out in horror and mom looks on thinking "where's that life insurance policy?"

Or am I reading too much into it?

[Shortbus]

That Popular Mechanics link was an interesting read, but the story photo on second glance looks a bit sinister. It's as though dad's been playing too hard and has had a stabbing pain in his chest, lets go of his goalie mallet and drops his hand to his knee as he bends over. Meanwhile blond daughter is calling out in horror and mom looks on thinking "where's that life insurance policy?"

Or am I reading too much into it?

VERY FUNNY  either a heart attack or took a puck to the twig and berries....for a minute there it looked like "threes company"....gotta love it....

thanks for the laugh, hit the spot!

[Silas (son of Silas)]

I forgot to say, this is Über cool. I have often wondered how I could go about building an air hockey table. I will be watching this thread very closely. Should be fun!

[ids]

That Popular Mechanics link was an interesting read, but the story photo on second glance looks a bit sinister. It's as though dad's been playing too hard and has had a stabbing pain in his chest, lets go of his goalie mallet and drops his hand to his knee as he bends over. Meanwhile blond daughter is calling out in horror and mom looks on thinking "where's that life insurance policy?"

Or am I reading too much into it?

lmao 

but now that you mention it....kinda reminds me of life in my own home.  The wife pictured also seems to be planning how to spend that insurance money too - she has that deep thought look I get when I think of how to spend the lottery winnings I plan on winning soon.


Shortbus - thanks for the heads up, reading the Skeeball thread now, definitely on the to-do list.

[thatpurplestuff]

Thanks for the kind words Shortbus!  Yeah Skeeball is absolutely still in the works, I'm in the process of revamping and adding multiplayer to the software as well as tweaking the ramp before I get things ready to paint.

That's one of the main reasons why I'm offering to help any way I can with this build... I know how difficult it is to build something that doesn't have a whole lot of documentation.  People like unclet (and many others) on this board have been invaluable in terms of getting information and dimensions that I normally wouldn't have access to.

Again, can't wait to see how this project turns out!

[ids]

I too am very appreciative of the members here, which is why I started this thread before I was in full build mode.  I was hoping for some input before spending time and money on dead-ends.  But based on the searching I've done.... not expecting a great deal.  The skeeball build...seems you had something to go on at the beginning?  Cant wait to see more progress on it.  I think I've bumped it up to my next project, above the cocktail cab, the dedicated vertical and dedicated horizontal, the bartop, the shuffleboard, the....  (my dream is to un-franken the panel as more cabs come alive).

Like I've read many times before - the mame cab was my first "real" project, and I immediately fell in love with the art of turning wood into sawdust (sorry trees).  I just love to build sh..stuff (sorry saint, caught myself there).  Mame cab delayed due to the dart board cabinet, the workshop bench, the...*(cutting wood to build sh-stuff)*..

tho I can't wait to complete things, I also need a place for them, another reason for delays.  Like most of you, I'm NOT living in a 40,000sq ft mansion.  Need to negotiate with the CFO, CEO, move stuff around, beg, plead, etc.

Sorry, not very project specific post...will stop.  All prior crap has been spottingly posted in my "blog" of sorts, rather than embarrass myself here.

Will take lots of pics and post anything relevant when I start drilling the four-thousand-something holes (sigh).

Also need to design the "goal" and puck return, etc...all in due time.

[TheGameFan]

tho I can't wait to complete things, I also need a place for them, another reason for delays.  Like most of you, I'm NOT living in a 40,000sq ft mansion.  Need to negotiate with the CFO, CEO, move stuff around, beg, plead, etc.

That's why I've change to building "minis". Have you thought of a mini or bartop Air Hockey?

[ids]

That's why I've change to building "minis". Have you thought of a mini or bartop Air Hockey?

Saw the mini's, very impressed (following the pinball lately), great work, but...mini air hockey...not sure about that.  Call me out on this if wrong, but much of the fun is watching the puck careen at the speed of sound across the large table.  A mini would have a certain cool factor to it, but would perhaps lose a bit in playability/fun.  Whereas Mame is great big or small (e.g. the GPWiz, still fun, even if the controls sometimes suck).

I do currently have "approval" for a games room, and space is being made (hence delay in project).  Only concern is ensuring enough power, but that's another adventure.  Oh, and getting 4x8 sheets of wood home (gave up the Grand Caravan for something that has no 4' hole in it :'( )

[TheGameFan]

Saw the mini's, very impressed (following the pinball lately), great work, but...mini air hockey...not sure about that.

I've been following it as well, along his mini Galaga, which inspired my mini/bartop QBert (in planning stages). I'll probably do a mini skeeball, visual pinball and/or air hockey at some point, but I have 3 other projects to finish first.

Glad to hear you've got a gameroom in the works though. I just have to make room wherever possible. My (only) full sized cab is actually going in the dining room, since there's nowhere else to put it!

[Number21]

If you make a mini air hockey table you could use poker chips as the puck.  I like the idea of a homebuilt full size one, will be interested to see the results.

[TheGameFan]

I like the idea of a homebuilt full size one, will be interested to see the results.

X2
It's definitely well thought out.

[ids]

One possible plan I'm considering.  This allows the entire air box to be supported by the legs quite nicely.  Was thinking angled aluminum for the sides - for the puck to bound off.  Read something somewhere about  an air filter.  I might just enclose the blower in a box and use a normal furnace filter.  This might reduce noise at the same time?



Picked up some 7-segment led thingies (another Active Surplus bargain, tube of 15 for $5).  I plan to build a simple circuit to drive them.  Thinking to use optical sensors for scoring to drive it all.  Guess I'll need a 5V wall wart to power it.


The clock showing here will actually be the signal from the optical sensor.  Given that I have so many of these, I may allow for double digit scoring.

(my 7-seg LED's are common anode, unlike the linked article, so I'll adjust accordingly, swapping the 4511 for a 7447)

[syph007]

How about this for a cheating fast way for a play surface.  White counter top laminate on pegboard.  You'd still have to drill through the laminate though, and probably build a support structure.  Just a thought.

[ids]

That's actually my plan - white laminate.  Saw a sheet at a local Rona for maybe $30.  I honestly can't think of anything better.

Was planning to use a sheet of pegboard to guide the drilling.  Clamp it on and go to town.  But was thinking to have something sturdier under the laminate for support.  However, I'll have to consider your idea, as I am concerned with how much airflow I'd get through 3/4" (mdf/ply) with such small holes.  I'd either have to drill larger holes in the wood (so we're up to 8000+ holes now), or hope it works as-is.  Using pegboard under the laminate would require more supporting pieces underneath...which may not be so bad.  In the pic above, the plan leaves 3.5" which just happens to match any *-by-4" piece of wood.

Surface markings: considering red sharpie for centre line, that sort of thing.  Paint would invariable add substance to the surface, which I want to avoid.  A permanent marker would not.

[syph007]

Cool, I'm excited to see how this goes.   Laminate is fairly rigid on its own.  I was visualizing that on top, pegboard, then ideally a metal grating, something rigid and uniform, but air permeable.

[ids]

Problem solved, got all i need from this site. 

syph - Given a 4'x8' sheet, and people leaning on it...correct me if wrong, but laminate, even if glued to pegboard....Now the metal grating, haven't thought about that.  I was wondering about rebar - a 4' length, here and there...  Overall, supporting the top has been the most vexing issue in my mind.  A sheet of wood that size will sag.  These guys go way too far...although, if one is willing to drill 4000 holes...hmmm.

I think the answer lies in some middle ground.  I'll look into metal grating.  Another option - occasional support..but under that support, probably some "joists" running fill width, hanging onto something even sturdier...or maybe it's all overkill....

It's definitely well thought out.

yeah, "well thought out" - it's that apparent?     Don't even know where to begin...well, begin with sheet goods, then... 

Saw a post somewhere mentioning the HomeDespot truck is only $20 - so maybe I'll start sooner than I thought.  Just need the CFO to approve the financing.  Since the mame cab isn't done, this will be a challenge.

[syph007]

Yep I had to rent a home depot van to get my 4x8 sheets home.  It was 20 bucks for 2 hours I believe. 

[Number21]

If you use metal rebar or angle that thing will weigh a ton.  Why not just use a 3/4" x 2" boards laid out in a grid.  All the strength you need to support it and you don't have to be Superman to move it.  Just my 2 cents. 

[ids]

If you use metal rebar or angle that thing will weigh a ton.  Why not just use a 3/4" x 2" boards laid out in a grid.  All the strength you need to support it and you don't have to be Superman to move it.  Just my 2 cents. 

You mean like the instructables link I posted earlier?  What they do seems like overkill, but perhaps a smaller number of the supports would be ok?

OTOH, what is supporting the supports?  The bottom of the box will also be, say 3/4" ply, and will also sag.  That's why I was thinking of running some "joists" sideways, 2-3? of them.  Any opinions greatly appreciated.

Thanks.

[Number21]

My bad i did not see that link earlier.  That is an interesting way to do it.   I was thinking of something like a grid made of 3/4" x 3" pine with large holes.  That might be overkill also.  You may be able to get away with some 1/8" aluminum angle.  Just a thought.

[ids]

Thanks again.  Every idea is food for thought.  So much to consider: weight, air-tightness, support. etc.  I really appreciate all the help, though.  I guess I need to plan for experimentation, and accept what comes.

Thanks.

[ids]

Edit: updated circuit diagrams and related commentary

Well, the G20 is offering me a few unplanned (and unpaid) days off, so the start date is now set - assuming I don't get veto'd on the home-front.

I've already started the soldering job to make the automatic scoring/display.  More work than I thought it would be, especially as electronics is not my thing.  Using this nice prototyping board for the main counter and decoder chips - socketed of course.  May not be obvious in the diagram below, but I'm going to chain the counters to allow for double digit scoring.  The displays will be on a separate board.  Thinking of linking them via DB15 connector or something.


You can get a more scalable view here.  If anyone knows anything about electronics, maybe you can validate this circuit before i cook something, or waste time.

Starting also to think about other options, for example, start the score at a certain point (10, 20, take your pick), and count down - first to zero is the winner.  That sort of thing.  The counters can be "preset" to a value, and count up or down, so some small variety of game options would be conceivable.

Thanks.

[ids]

Started modelling via sketchup
 

Missing goals, legs, blower, 4000+ holes, etc.  This is just the main air-box.  Some dimensions seem to be off by just a little bit.  See attached model for more detail - shows an exploded view (as above) and regular (all put together) view.

Shopping list, so far:

Qty	Size	Desc
1	4’x8’	white laminate
1	3/4”x4’x8’	sheet wood (MDF, particle board, OSD, one-side-good ply, etc, to support laminate)
1	3/4”x4’x8’	sheet wood (bottom of plenum)
3	1”x3”x4’	straight edge wood (MDF or other, support playing surface)
1	3/4"x4'x8'	plenum sides
1	4’x8’	Peg Board (drilling guide) - not shown
3	2”x4”x4’	support plenum from underneath
3	1”x8’	angle aluminum (playfield vertical edges) - not shown
1	1”x8’	angle aluminum (outside vertical box corners) - not shown
2	1”x8’	angle aluminum (leg outside corners) - not shown

Will be starting within days, any opinions welcome at this point.

Oh - need a name for the project too - thinking of going with a basic black theme, but need to stamp a name on the side to break up the monotony.

[ivwshane]

Keep the great documentation going! If I ever get the space I would love to build one of these!

[ids]

Thanks for the encouragement.  I'll document as much as I can, and take lots of pics along the way.  There are certain choices to make and mine may not always be right, but at least we can all learn from the attempt.

The look I am going for (until I change my mind) is like this:


If I can find blue laminate, I may go with that too.

Came upon the Dynamo Parts Catalogue recently - most interested in the Puck Drop Guide.  I may try to reproduce something like that.

Well, G20 weekend starts tomorrow, so unless the boss veto's my plans, I'll be off renting the HD truck in the morning...

[Silas (son of Silas)]

There are a few home build air hockey tables on YouTube:

[ids]

Thanks for those links.  I do a lot of my research during....uh...the 9-5 hours, which means no youtube, and a lot of other sites.

I think I've seen the second one - isn't that the instructables build?

In the interim, I keep playing with the Sketchup model, trying to get closer to that dynamo table I linked earlier.  My lack of sketchup knowledge combined with those angles is killing me.  Which is also a segue into updates to the shopping list, which are pending.  I'll update when I get a bit more figured out.  I'll also add either estimated or real costs (will be Canadian$, so close to $US too)

I think I have a name for the project, which is the inspiration for delaying the start till now: G20

side note: watching what seemed like a couple hundred billion cops converge, then hearing protesters on their way, then the building shakes, seeing the "OMfG a Bomb" panic in everyones eyes (we had an earthquake at that very momemt, 5 on the Richter)...Open to other names, but for now, G20 is sort of stuck in my mind.

Cheers

[ids]

Sorry for the lack of progress.

I had to work through most of the G20 weekend (from home, thank god).  I did get to take some measurements of a real dynamo in an arcade (looking like the fool).  I tried to incorporate those.  The angle of the sides is something of an estimate. 

The attached model, as shown above, no longer has an exploded view, which is easy enough to make, but does have a plain view as well as as view showing an early concept for mounting the legs (shown in this image). The model is not at a point where one could actually build it, but is getting close.  The sides are angled at 5 degrees, which makes measuring things a real pain.  The goals are not complete (stating the obvious?).  The 2x4 support at the end runs right through the goals - this need to be addressed.  I am also thinking of using steel as support at the top (shown), then bending a curve into another piece of metal to discourage bounce-out, .....

The goal is to paint it black, but sketchup sucks at rendering, so I chose grey for now.  Also, I'm thinking of using 5/8" particle board everywhere, whereas the model uses 3/4" sheets.  Open to suggestions on this.


Overall advice is welcome and encouraged?

Thanks for the patience 

updates to come

[ids]

Updated counter circuit (see below).  An SVG version can be found here.  It shows a single 7-seg display, but I am thinking of going with double-digit scoring per player.  The diagram shows how to add the second digit.  It also contains some LED's I've added for debugging, and which are otherwise not required.  The de-bounce circuitry is another addition.

Updated build plans also.  I guess details are not visible in the attached pic.  I can upload the sketchup model if anyone cares.

Working on a cutting diagram, updated shopping list (incl pricing), etc.

Decided (for the moment) that all supports will be 3/4" strips of ply.  Now that I have a table saw, this is quite doable.

Also, may adjust the rails - as it is, it's too easy to place a drink there....and hilarity ensues  :'(  I'm thinking maybe to add just enough slope (away from play surface) to discourage placement of beverages.

Fretting over decision for play surface itself:  Laminate/formica, or Aluminum Composite Panel, or....

Strongly considering using the real deal leg levellers too:


I expect the build process to begin with the next few weeks (months?) as most of life's other priorities have been dealt with.  Updates to come...

Edit: Fixed circuit diagram

[ragnar]

AWESOME PROJECT!

Any estimates on total cost?

For what it is worth, I considered making a shuffle board table due to the cost that they noramlly incur.  The high end tables are 9-18 feet long I think.  They get way expensive:
http://www.pooltablesusa.com/shuffleboard-tables/

The thing is, doing this kind of build would require alot of wood (ie: money) among other things.  It's on the short list of things I would like to build but I really have to determine design/cost related issues.  That deck needs to be thick to prevent warping, thus the higher costs to build.