Custom Pinball Design

Cabinet :: Design :: Base

There are basically three Cabinet options for a custom Pinball machine:

  • Purchase a new reproduction.
  • Find a used beater to refurbish.
  • Build new from scratch.

Any of these are good, viable options that I would recommend, but there are pros and cons with each. I’ll detail these in the order of preference…

Build From Scratch

I’ll start with the down side: It’s likely to be either more expensive or more time consuming than the other options.

Custom Pinball Cabinet

Full CAD design of custom pinball cabinet with head.

But there are some big up-sides…

  • Cheaper than buying new (but not cheaper than used).
  • Less bloat, so overall the machine can be lighter.
  • More engineering options for setting the rake angle and depth.
  • Artistic ownership of the final product.

and best of all…

  • The pride of doing it yourself.

Here is an example Cabinet design in CAD, where all the base pieces are laid out on a single 4’x8′ sheet of plywood ( 3/4″), which you can download as DXF or SVG here.

Custom Pinball Cabinet Template

All the necessary base Cabinet parts laid out on a single 4’x8′ sheet.

Hidden lines are drawn in magenta, and are there to show where a miter-lock joint will be. If you don’t have access to a router table, or don’t feel comfortable creating a miter joint, you would simply cut along two of the magenta lines and create a butt-joint. Preferably cut the side panels to preserve the flush finish on the front, which is most visible.

The large panels are cut with a circular saw, and the smaller pieces can be band saw or jig saw. Worst case, if resources are limited, it should be possible to cut all the parts out with a jig saw.

Depending on what type of wood you chose (MDF, plywood, etc), the cost of a 4’x8′ sheet is going to run about $50-$100. I recommend paying a little extra for quality, even though the finished product will be painted. Good quality plywood will end up looking better, last longer and less likely to warp.

The other cost is going to be in the hardware. You will still need to source of the components of a vintage cabinet (see below), or purchase new from a company like VirtuaPin

A new hardware kit runs about $400. Lower cost options can be found if you’re willing to lurk on eBay. But even when used, be prepared to spend on the order of $200 total for legs, coin door, side rails, lockdown bar and other hardware. If you really need a low-cost option, then best to…

Refurbish a Used Cabinet

This is a good, cheap option that has worked well in the past. However, depending on your location, an old beater cabinet could be hard to find. Best bet is to keep an eye on Craigslist and eBay, or network with local machine owners.

Almost all “standard” width Cabinets will accept a “standard” size playfield with a few modifications. Usually the lockdown bar bracket also serves as a receiver for the playfield hangar brackets. So when laying out your playfield, you may have to shift these to match your existing Cabinet hardware.

If you do go this route, try and pick up a Cabinet that has most (or all) of the hardware still attached. This would include:

  • Coin door with mechs.
  • Lockdown bar and receiver bracket.
  • Side rails.
  • Flipper buttons.
  • Leg mounting plate brackets.

I didn’t include Legs in this list because often a perfectly good cabinet might be missing the legs, and second, you will probably want to purchase a new shiny set of legs anyway. These can be found for as low as $50 for a set at places like Pinball Life.

If there are any electronics in the cabinet, you can probably re-use things like the power switch, AC cord, filter, fuse, etc. but you probably won’t need the transformer…

Later on, there will be more posts about the control system. In this section, we detail how to install all new switch-mode power electronics, which are easer, safer and lighter than the old-style transformers.

Buy a Reproduction Cabinet

There has been a renewed interest in reproduction pinball cabinets with the introduction of “Visual Pinball”. We’ll go into this more in later posts, but basically people are creating computer-based virtual pinball games, and installing large flat-screen monitors into cabinets for a more realistic game playing experience. We can take advantage of this new phenomenon and cottage industry that has grown up around it.

The most popular off-the-shelf reproduction cabinet is made by VirtuaPin.

In the DIY category, you can find cabinets in the $300 – $500 range depending on the finish. On top of this, you will need a hardware kit that runs about $400. So we are talking about a total of around $700 – $900, but bear in mind that the hardware is about half of that cost, and you will still need to buy that with a custom cabinet (although maybe cheaper on eBay).

Playfield :: Fabrication :: Lenses

A majority of the holes you will cut into your custom Playfield will be for Lenses, so this is how we will kick off the actual fabrication of a blank table… Vintage lenses come in several standard sizes, typically 1″, 3/4″ and 5/8″. Rollover targets are also treated as lenses, and are 1 1/8″. Newer games added other sizes and shapes, but we will focus on these, plus a couple of vintage Arrow Lenses. All standard lenses are 1/4″ thick, which is an important feature for fabrication and installation.

Custom Playfield CAD File

Screenshot showing several lens sizes with retaining ledge visible.

Above is a screenshot from a CAD program showing several lens sizes with the retaining ledge visible.

You can find a selection of sizes from many different suppliers, but here are a few examples from Marco Specialties:

Notice that there are a variety of options aside from just color. There are transparent, opaque, star patterns or just plain versions. A couple of  other important things to note:

  • The decision on which lens to use (color vs white, transparent vs opaque, star vs flat) is going to be largely based on what type of lighting you will have, and what the specific application is. I prefer to use LED bulbs under lenses, so I typically go with White or Clear. The vinyl Playfield overlay is translucent, so the final color can be chosen later. If you are using incandescent bulbs, it would be better to use a colored lens. For lenses that have lettering on top (not uncommon), I like plain opaque White. When an indicator really needs to stand out, I go for a transparent colored lens with a star pattern, and same color LED bulb underneath. The end effect looks great and has a vintage feel.
  • All lenses have a letter (e.g. “A”, see above for more examples) molded into the top surface. These have to be removed by sanding. I typically glue the lenses in slightly “proud”, and then sand down the whole Playfield as part of the finishing process. Alternatively, you could pre-sand the them on a belt sander, but the results are sometimes uneven.
Custom Pinball Lens Shapes

CAD drawing of various standard lens shapes, available here.

Here are the steps to drill and insert lenses:

  • Print out your Playfield. This needs to be done full-size on paper using a large-format printer. I do this at Kinko’s or FedEx, and it’s very cheap for black and white.

 

Custom Playfield Fabrication

Apply full-scale CAD layout to blank Playfield.

  • Dimple with spot drill. I typically use a #43 (0.89″) bit, which is the standard pilot size for a #4 screw. Apply your Playfield CAD printout to your blank, and drill through your plywood at the center location of all lenses.
Custom Pinball Fabrication

Spot drill a pilot hole o guide the Forstner bit.

  • Forstner bit front side. Using a “Forstner” bit the same size as your lens, drill down slightly less than 1/4″. I usually make a jig in each lens diameter to gauge depth. When I feel I’m close to the final depth, I’ll slow down the RPMs and stop several times to check with the gauge.
Forstner Bit for Playfield Lens

Drill pocket 1/4″ deep on front side, check with lens jig.

  • Forstner bit back side. After doing all the fronts (usually one size at a time), flip to the back side an use a bit 1/8″ smaller than the lens diameter. This provides a lip or ledge for the lens to sit on. Coming in from the back does two things: you’re using the existing spot drill hole so there’s less drift, and the surface edges will be cleaner since they don’t risk being punched out from the front.
Custom Pinball Playfield Insert

Flip over and drill from the back with 1/8″ smaller Forstner bit.

  • Glue all lenses in. I typically use wood glue in case of mistakes, but you can be more aggressive and use clear epoxy. Use a finger from the back side to level and prevent the lens from dropping to far down. Let the glue dry… then…
  • Sand. I start with about 180 grit to get the plastic lenses flush, then switch to 220 then 320.

There are other processes later that will seal and clear coat the lenses to bring back their shine, and we’ll cover that later…

Playfield :: Hardware :: Bumpers

One of the most ubiquitous pieces of Playfield hardware is the Bumper.

It has at times gone by the name “Thumper”, “Jet” or “Pop Bumper”, but when people say “Bumper” they are generally referring to the switch-and- coil-activated mechanical Bumper that is standard to most modern games. At one time these Bumpers were passive, with just a rubber ring and a switch to add to the score, hence the need to have names to distinguish active Bumpers. But by the time of Pinball’s peak in the mid-80’s, most all Bumpers were active, except for a few notable games like “Silverball Mania” or “Space Invaders”.

Most machines typically have three Bumpers, but almost any combination of number or location you can think of has probably been tried. This is where the grammar and language of Pinball comes in…

If you are unfamiliar with all the Bumper variations that have been used it the past, check out the Internet Pinball Database (IPDB), and the reproductions section of the Visual Pinball (VP) website. When you design your game, you should be aware of what other games have used similar layouts. Even if you are not trying to emulate or reference vintage tables, there will always be some comparison and connotation associated with them. It’s important to understand this grammar so as to not create some unintended meaning.

The “standard” Bumper has undergone some evolution to make things easier for manufacturing, assembly and repair, even though the basic components remain the same. Here are representative examples:

  • Evolution #1 : Added Nutplate: The earliest improvement was to add a plate with pre-tapped holes.

Gottlieb Thumper

  • Evolution #2 : Combined Plate and Switch: The second improvement was a plate with built-in mount for a spoon switch. This unit could be built as a sub-assembly prior to installation.

Stern Thumper

  • Evolution #3 : Molded Plastic : An incremental improvement to number #2, this was probably a cost savings, but also presented a cleaner fit and finish on the top play surface.

Bally Thumper

Any of these would be a good choice for a custom pinball machine. You would want to make the decision early on, however, since the Playfield would have to be drilled to accept the specific hardware. Most likely, you will base this on what’s available in your stock or on eBay.

It’s much cheaper to buy a used Bumper unit, and if necessary rebuild with new top-side parts for cosmetic considerations. A used unit that already has the brackets, coil, metal ring assembly and the switch, can be re-built to like-new condition with the following parts:

Bumper re-build parts

These can be found at Marco Specialties or Pinball Life:

And if you decide to start fresh instead of rebuilding, you can find this as an assembly:

Here’s what the top-side parts look like assembled:

Assembled Bumper Parts

If your assembly already has a base, you probably will not need the Playfield insert. These parts can then be added to the rest of the sub-assembly, making the installation and future repair that much easier.

Downloads:

  • CAD diagram of EV2 version of Bumper, showing Playfield cutout. You can right click here and “save as”, or click through to preview in most browsers. Keep this item as a template in your custom pinball artwork file, then import into Inkscape or other drawing programs.